pg_backup_archiver.c

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/*-------------------------------------------------------------------------
 *
 * pg_backup_archiver.c
 *
 *  Private implementation of the archiver routines.
 *
 *  See the headers to pg_restore for more details.
 *
 * Copyright (c) 2000, Philip Warner
 *  Rights are granted to use this software in any way so long
 *  as this notice is not removed.
 *
 *  The author is not responsible for loss or damages that may
 *  result from its use.
 *
 *
 * IDENTIFICATION
 *      src/bin/pg_dump/pg_backup_archiver.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres_fe.h"
 
#include <ctype.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>
#ifdef WIN32
#include <io.h>
#endif
 
#include "catalog/pg_class_d.h"
#include "catalog/pg_largeobject_metadata_d.h"
#include "catalog/pg_shdepend_d.h"
#include "common/string.h"
#include "compress_io.h"
#include "dumputils.h"
#include "fe_utils/string_utils.h"
#include "lib/binaryheap.h"
#include "lib/stringinfo.h"
#include "libpq/libpq-fs.h"
#include "parallel.h"
#include "pg_backup_archiver.h"
#include "pg_backup_db.h"
#include "pg_backup_utils.h"
 
#define TEXT_DUMP_HEADER "--\n-- PostgreSQL database dump\n--\n\n"
#define TEXT_DUMPALL_HEADER "--\n-- PostgreSQL database cluster dump\n--\n\n"
 
#define TOC_PREFIX_NONE     ""
#define TOC_PREFIX_DATA     "Data for "
#define TOC_PREFIX_STATS    "Statistics for "
 
static ArchiveHandle *_allocAH(const char *FileSpec, const ArchiveFormat fmt,
                               const pg_compress_specification compression_spec,
                               bool dosync, ArchiveMode mode,
                               SetupWorkerPtrType setupWorkerPtr,
                               DataDirSyncMethod sync_method);
static void _getObjectDescription(PQExpBuffer buf, const TocEntry *te);
static void _printTocEntry(ArchiveHandle *AH, TocEntry *te, const char *pfx);
static void _doSetFixedOutputState(ArchiveHandle *AH);
static void _doSetSessionAuth(ArchiveHandle *AH, const char *user);
static void _reconnectToDB(ArchiveHandle *AH, const char *dbname);
static void _becomeUser(ArchiveHandle *AH, const char *user);
static void _becomeOwner(ArchiveHandle *AH, TocEntry *te);
static void _selectOutputSchema(ArchiveHandle *AH, const char *schemaName);
static void _selectTablespace(ArchiveHandle *AH, const char *tablespace);
static void _selectTableAccessMethod(ArchiveHandle *AH, const char *tableam);
static void _printTableAccessMethodNoStorage(ArchiveHandle *AH,
                                             TocEntry *te);
static void processEncodingEntry(ArchiveHandle *AH, TocEntry *te);
static void processStdStringsEntry(ArchiveHandle *AH, TocEntry *te);
static void processSearchPathEntry(ArchiveHandle *AH, TocEntry *te);
static int  _tocEntryRequired(TocEntry *te, teSection curSection, ArchiveHandle *AH);
static RestorePass _tocEntryRestorePass(TocEntry *te);
static bool _tocEntryIsACL(TocEntry *te);
static void _disableTriggersIfNecessary(ArchiveHandle *AH, TocEntry *te);
static void _enableTriggersIfNecessary(ArchiveHandle *AH, TocEntry *te);
static bool is_load_via_partition_root(TocEntry *te);
static void buildTocEntryArrays(ArchiveHandle *AH);
static void _moveBefore(TocEntry *pos, TocEntry *te);
static int  _discoverArchiveFormat(ArchiveHandle *AH);
 
static int  RestoringToDB(ArchiveHandle *AH);
static void dump_lo_buf(ArchiveHandle *AH);
static void dumpTimestamp(ArchiveHandle *AH, const char *msg, time_t tim);
static void SetOutput(ArchiveHandle *AH, const char *filename,
                      const pg_compress_specification compression_spec);
static CompressFileHandle *SaveOutput(ArchiveHandle *AH);
static void RestoreOutput(ArchiveHandle *AH, CompressFileHandle *savedOutput);
 
static int  restore_toc_entry(ArchiveHandle *AH, TocEntry *te, bool is_parallel);
static void restore_toc_entries_prefork(ArchiveHandle *AH,
                                        TocEntry *pending_list);
static void restore_toc_entries_parallel(ArchiveHandle *AH,
                                         ParallelState *pstate,
                                         TocEntry *pending_list);
static void restore_toc_entries_postfork(ArchiveHandle *AH,
                                         TocEntry *pending_list);
static void pending_list_header_init(TocEntry *l);
static void pending_list_append(TocEntry *l, TocEntry *te);
static void pending_list_remove(TocEntry *te);
static int  TocEntrySizeCompareQsort(const void *p1, const void *p2);
static int  TocEntrySizeCompareBinaryheap(void *p1, void *p2, void *arg);
static void move_to_ready_heap(TocEntry *pending_list,
                               binaryheap *ready_heap,
                               RestorePass pass);
static TocEntry *pop_next_work_item(binaryheap *ready_heap,
                                    ParallelState *pstate);
static void mark_dump_job_done(ArchiveHandle *AH,
                               TocEntry *te,
                               int status,
                               void *callback_data);
static void mark_restore_job_done(ArchiveHandle *AH,
                                  TocEntry *te,
                                  int status,
                                  void *callback_data);
static void fix_dependencies(ArchiveHandle *AH);
static bool has_lock_conflicts(TocEntry *te1, TocEntry *te2);
static void repoint_table_dependencies(ArchiveHandle *AH);
static void identify_locking_dependencies(ArchiveHandle *AH, TocEntry *te);
static void reduce_dependencies(ArchiveHandle *AH, TocEntry *te,
                                binaryheap *ready_heap);
static void mark_create_done(ArchiveHandle *AH, TocEntry *te);
static void inhibit_data_for_failed_table(ArchiveHandle *AH, TocEntry *te);
 
static void StrictNamesCheck(RestoreOptions *ropt);
 
 
/*
 * Allocate a new DumpOptions block containing all default values.
 */
DumpOptions *
NewDumpOptions(void)
{
    DumpOptions *opts = (DumpOptions *) pg_malloc(sizeof(DumpOptions));
 
    InitDumpOptions(opts);
    return opts;
}
 
/*
 * Initialize a DumpOptions struct to all default values
 */
void
InitDumpOptions(DumpOptions *opts)
{
    memset(opts, 0, sizeof(DumpOptions));
    /* set any fields that shouldn't default to zeroes */
    opts->include_everything = true;
    opts->cparams.promptPassword = TRI_DEFAULT;
    opts->dumpSections = DUMP_UNSECTIONED;
    opts->dumpSchema = true;
    opts->dumpData = true;
    opts->dumpStatistics = false;
}
 
/*
 * Create a freshly allocated DumpOptions with options equivalent to those
 * found in the given RestoreOptions.
 */
DumpOptions *
dumpOptionsFromRestoreOptions(RestoreOptions *ropt)
{
    DumpOptions *dopt = NewDumpOptions();
 
    /* this is the inverse of what's at the end of pg_dump.c's main() */
    dopt->cparams.dbname = ropt->cparams.dbname ? pg_strdup(ropt->cparams.dbname) : NULL;
    dopt->cparams.pgport = ropt->cparams.pgport ? pg_strdup(ropt->cparams.pgport) : NULL;
    dopt->cparams.pghost = ropt->cparams.pghost ? pg_strdup(ropt->cparams.pghost) : NULL;
    dopt->cparams.username = ropt->cparams.username ? pg_strdup(ropt->cparams.username) : NULL;
    dopt->cparams.promptPassword = ropt->cparams.promptPassword;
    dopt->outputClean = ropt->dropSchema;
    dopt->dumpData = ropt->dumpData;
    dopt->dumpSchema = ropt->dumpSchema;
    dopt->dumpSections = ropt->dumpSections;
    dopt->dumpStatistics = ropt->dumpStatistics;
    dopt->if_exists = ropt->if_exists;
    dopt->column_inserts = ropt->column_inserts;
    dopt->aclsSkip = ropt->aclsSkip;
    dopt->outputSuperuser = ropt->superuser;
    dopt->outputCreateDB = ropt->createDB;
    dopt->outputNoOwner = ropt->noOwner;
    dopt->outputNoTableAm = ropt->noTableAm;
    dopt->outputNoTablespaces = ropt->noTablespace;
    dopt->disable_triggers = ropt->disable_triggers;
    dopt->use_setsessauth = ropt->use_setsessauth;
    dopt->disable_dollar_quoting = ropt->disable_dollar_quoting;
    dopt->dump_inserts = ropt->dump_inserts;
    dopt->no_comments = ropt->no_comments;
    dopt->no_policies = ropt->no_policies;
    dopt->no_publications = ropt->no_publications;
    dopt->no_security_labels = ropt->no_security_labels;
    dopt->no_subscriptions = ropt->no_subscriptions;
    dopt->lockWaitTimeout = ropt->lockWaitTimeout;
    dopt->include_everything = ropt->include_everything;
    dopt->enable_row_security = ropt->enable_row_security;
    dopt->sequence_data = ropt->sequence_data;
    dopt->restrict_key = ropt->restrict_key ? pg_strdup(ropt->restrict_key) : NULL;
 
    return dopt;
}
 
 
/*
 *  Wrapper functions.
 *
 *  The objective is to make writing new formats and dumpers as simple
 *  as possible, if necessary at the expense of extra function calls etc.
 *
 */
 
/*
 * The dump worker setup needs lots of knowledge of the internals of pg_dump,
 * so it's defined in pg_dump.c and passed into OpenArchive. The restore worker
 * setup doesn't need to know anything much, so it's defined here.
 */
static void
setupRestoreWorker(Archive *AHX)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
 
    AH->ReopenPtr(AH);
}
 
 
/* Create a new archive */
/* Public */
Archive *
CreateArchive(const char *FileSpec, const ArchiveFormat fmt,
              const pg_compress_specification compression_spec,
              bool dosync, ArchiveMode mode,
              SetupWorkerPtrType setupDumpWorker,
              DataDirSyncMethod sync_method)
 
{
    ArchiveHandle *AH = _allocAH(FileSpec, fmt, compression_spec,
                                 dosync, mode, setupDumpWorker, sync_method);
 
    return (Archive *) AH;
}
 
/* Open an existing archive */
/* Public */
Archive *
OpenArchive(const char *FileSpec, const ArchiveFormat fmt)
{
    ArchiveHandle *AH;
    pg_compress_specification compression_spec = {0};
 
    compression_spec.algorithm = PG_COMPRESSION_NONE;
    AH = _allocAH(FileSpec, fmt, compression_spec, true,
                  archModeRead, setupRestoreWorker,
                  DATA_DIR_SYNC_METHOD_FSYNC);
 
    return (Archive *) AH;
}
 
/* Public */
void
CloseArchive(Archive *AHX)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
 
    AH->ClosePtr(AH);
 
    /* Close the output */
    errno = 0;
    if (!EndCompressFileHandle(AH->OF))
        pg_fatal("could not close output file: %m");
}
 
/* Public */
void
SetArchiveOptions(Archive *AH, DumpOptions *dopt, RestoreOptions *ropt)
{
    /* Caller can omit dump options, in which case we synthesize them */
    if (dopt == NULL && ropt != NULL)
        dopt = dumpOptionsFromRestoreOptions(ropt);
 
    /* Save options for later access */
    AH->dopt = dopt;
    AH->ropt = ropt;
}
 
/* Public */
void
ProcessArchiveRestoreOptions(Archive *AHX)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
    RestoreOptions *ropt = AH->public.ropt;
    TocEntry   *te;
    teSection   curSection;
 
    /* Decide which TOC entries will be dumped/restored, and mark them */
    curSection = SECTION_PRE_DATA;
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        /*
         * When writing an archive, we also take this opportunity to check
         * that we have generated the entries in a sane order that respects
         * the section divisions.  When reading, don't complain, since buggy
         * old versions of pg_dump might generate out-of-order archives.
         */
        if (AH->mode != archModeRead)
        {
            switch (te->section)
            {
                case SECTION_NONE:
                    /* ok to be anywhere */
                    break;
                case SECTION_PRE_DATA:
                    if (curSection != SECTION_PRE_DATA)
                        pg_log_warning("archive items not in correct section order");
                    break;
                case SECTION_DATA:
                    if (curSection == SECTION_POST_DATA)
                        pg_log_warning("archive items not in correct section order");
                    break;
                case SECTION_POST_DATA:
                    /* ok no matter which section we were in */
                    break;
                default:
                    pg_fatal("unexpected section code %d",
                             (int) te->section);
                    break;
            }
        }
 
        if (te->section != SECTION_NONE)
            curSection = te->section;
 
        te->reqs = _tocEntryRequired(te, curSection, AH);
    }
 
    /* Enforce strict names checking */
    if (ropt->strict_names)
        StrictNamesCheck(ropt);
}
 
/* Public */
void
RestoreArchive(Archive *AHX)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
    RestoreOptions *ropt = AH->public.ropt;
    bool        parallel_mode;
    TocEntry   *te;
    CompressFileHandle *sav;
 
    AH->stage = STAGE_INITIALIZING;
 
    /*
     * If we're going to do parallel restore, there are some restrictions.
     */
    parallel_mode = (AH->public.numWorkers > 1 && ropt->useDB);
    if (parallel_mode)
    {
        /* We haven't got round to making this work for all archive formats */
        if (AH->ClonePtr == NULL || AH->ReopenPtr == NULL)
            pg_fatal("parallel restore is not supported with this archive file format");
 
        /* Doesn't work if the archive represents dependencies as OIDs */
        if (AH->version < K_VERS_1_8)
            pg_fatal("parallel restore is not supported with archives made by pre-8.0 pg_dump");
 
        /*
         * It's also not gonna work if we can't reopen the input file, so
         * let's try that immediately.
         */
        AH->ReopenPtr(AH);
    }
 
    /*
     * Make sure we won't need (de)compression we haven't got
     */
    if (AH->PrintTocDataPtr != NULL)
    {
        for (te = AH->toc->next; te != AH->toc; te = te->next)
        {
            if (te->hadDumper && (te->reqs & REQ_DATA) != 0)
            {
                char       *errmsg = supports_compression(AH->compression_spec);
 
                if (errmsg)
                    pg_fatal("cannot restore from compressed archive (%s)",
                             errmsg);
                else
                    break;
            }
        }
    }
 
    /*
     * Prepare index arrays, so we can assume we have them throughout restore.
     * It's possible we already did this, though.
     */
    if (AH->tocsByDumpId == NULL)
        buildTocEntryArrays(AH);
 
    /*
     * If we're using a DB connection, then connect it.
     */
    if (ropt->useDB)
    {
        pg_log_info("connecting to database for restore");
        if (AH->version < K_VERS_1_3)
            pg_fatal("direct database connections are not supported in pre-1.3 archives");
 
        /*
         * We don't want to guess at whether the dump will successfully
         * restore; allow the attempt regardless of the version of the restore
         * target.
         */
        AHX->minRemoteVersion = 0;
        AHX->maxRemoteVersion = 9999999;
 
        ConnectDatabaseAhx(AHX, &ropt->cparams, false);
 
        /*
         * If we're talking to the DB directly, don't send comments since they
         * obscure SQL when displaying errors
         */
        AH->noTocComments = 1;
    }
 
    /*
     * Work out if we have an implied schema-less restore. This can happen if
     * the dump excluded the schema or the user has used a toc list to exclude
     * all of the schema data. All we do is look for schema entries - if none
     * are found then we unset the dumpSchema flag.
     *
     * We could scan for wanted TABLE entries, but that is not the same as
     * data-only. At this stage, it seems unnecessary (6-Mar-2001).
     */
    if (ropt->dumpSchema)
    {
        bool        no_schema_found = true;
 
        for (te = AH->toc->next; te != AH->toc; te = te->next)
        {
            if ((te->reqs & REQ_SCHEMA) != 0)
            {
                no_schema_found = false;
                break;
            }
        }
        if (no_schema_found)
        {
            ropt->dumpSchema = false;
            pg_log_info("implied no-schema restore");
        }
    }
 
    /*
     * Setup the output file if necessary.
     */
    sav = SaveOutput(AH);
    if (ropt->filename || ropt->compression_spec.algorithm != PG_COMPRESSION_NONE)
        SetOutput(AH, ropt->filename, ropt->compression_spec);
 
    ahprintf(AH, "--\n-- PostgreSQL database dump\n--\n\n");
 
    /*
     * If generating plain-text output, enter restricted mode to block any
     * unexpected psql meta-commands.  A malicious source might try to inject
     * a variety of things via bogus responses to queries.  While we cannot
     * prevent such sources from affecting the destination at restore time, we
     * can block psql meta-commands so that the client machine that runs psql
     * with the dump output remains unaffected.
     */
    if (ropt->restrict_key)
        ahprintf(AH, "\\restrict %s\n\n", ropt->restrict_key);
 
    if (AH->archiveRemoteVersion)
        ahprintf(AH, "-- Dumped from database version %s\n",
                 AH->archiveRemoteVersion);
    if (AH->archiveDumpVersion)
        ahprintf(AH, "-- Dumped by pg_dump version %s\n",
                 AH->archiveDumpVersion);
 
    ahprintf(AH, "\n");
 
    if (AH->public.verbose)
        dumpTimestamp(AH, "Started on", AH->createDate);
 
    if (ropt->single_txn)
    {
        if (AH->connection)
            StartTransaction(AHX);
        else
            ahprintf(AH, "BEGIN;\n\n");
    }
 
    /*
     * Establish important parameter values right away.
     */
    _doSetFixedOutputState(AH);
 
    AH->stage = STAGE_PROCESSING;
 
    /*
     * Drop the items at the start, in reverse order
     */
    if (ropt->dropSchema)
    {
        for (te = AH->toc->prev; te != AH->toc; te = te->prev)
        {
            AH->currentTE = te;
 
            /*
             * In createDB mode, issue a DROP *only* for the database as a
             * whole.  Issuing drops against anything else would be wrong,
             * because at this point we're connected to the wrong database.
             * (The DATABASE PROPERTIES entry, if any, should be treated like
             * the DATABASE entry.)
             */
            if (ropt->createDB)
            {
                if (strcmp(te->desc, "DATABASE") != 0 &&
                    strcmp(te->desc, "DATABASE PROPERTIES") != 0)
                    continue;
            }
 
            /* Otherwise, drop anything that's selected and has a dropStmt */
            if (((te->reqs & (REQ_SCHEMA | REQ_DATA)) != 0) && te->dropStmt)
            {
                bool        not_allowed_in_txn = false;
 
                pg_log_info("dropping %s %s", te->desc, te->tag);
 
                /*
                 * In --transaction-size mode, we have to temporarily exit our
                 * transaction block to drop objects that can't be dropped
                 * within a transaction.
                 */
                if (ropt->txn_size > 0)
                {
                    if (strcmp(te->desc, "DATABASE") == 0 ||
                        strcmp(te->desc, "DATABASE PROPERTIES") == 0)
                    {
                        not_allowed_in_txn = true;
                        if (AH->connection)
                            CommitTransaction(AHX);
                        else
                            ahprintf(AH, "COMMIT;\n");
                    }
                }
 
                /* Select owner and schema as necessary */
                _becomeOwner(AH, te);
                _selectOutputSchema(AH, te->namespace);
 
                /*
                 * Now emit the DROP command, if the object has one.  Note we
                 * don't necessarily emit it verbatim; at this point we add an
                 * appropriate IF EXISTS clause, if the user requested it.
                 */
                if (strcmp(te->desc, "BLOB METADATA") == 0)
                {
                    /* We must generate the per-blob commands */
                    if (ropt->if_exists)
                        IssueCommandPerBlob(AH, te,
                                            "SELECT pg_catalog.lo_unlink(oid) "
                                            "FROM pg_catalog.pg_largeobject_metadata "
                                            "WHERE oid = '", "'");
                    else
                        IssueCommandPerBlob(AH, te,
                                            "SELECT pg_catalog.lo_unlink('",
                                            "')");
                }
                else if (*te->dropStmt != '\0')
                {
                    if (!ropt->if_exists ||
                        strncmp(te->dropStmt, "--", 2) == 0)
                    {
                        /*
                         * Without --if-exists, or if it's just a comment (as
                         * happens for the public schema), print the dropStmt
                         * as-is.
                         */
                        ahprintf(AH, "%s", te->dropStmt);
                    }
                    else
                    {
                        /*
                         * Inject an appropriate spelling of "if exists".  For
                         * old-style large objects, we have a routine that
                         * knows how to do it, without depending on
                         * te->dropStmt; use that.  For other objects we need
                         * to parse the command.
                         */
                        if (strcmp(te->desc, "BLOB") == 0)
                        {
                            DropLOIfExists(AH, te->catalogId.oid);
                        }
                        else
                        {
                            char       *dropStmt = pg_strdup(te->dropStmt);
                            char       *dropStmtOrig = dropStmt;
                            PQExpBuffer ftStmt = createPQExpBuffer();
 
                            /*
                             * Need to inject IF EXISTS clause after ALTER
                             * TABLE part in ALTER TABLE .. DROP statement
                             */
                            if (strncmp(dropStmt, "ALTER TABLE", 11) == 0)
                            {
                                appendPQExpBufferStr(ftStmt,
                                                     "ALTER TABLE IF EXISTS");
                                dropStmt = dropStmt + 11;
                            }
 
                            /*
                             * ALTER TABLE..ALTER COLUMN..DROP DEFAULT does
                             * not support the IF EXISTS clause, and therefore
                             * we simply emit the original command for DEFAULT
                             * objects (modulo the adjustment made above).
                             *
                             * Likewise, don't mess with DATABASE PROPERTIES.
                             *
                             * If we used CREATE OR REPLACE VIEW as a means of
                             * quasi-dropping an ON SELECT rule, that should
                             * be emitted unchanged as well.
                             *
                             * For other object types, we need to extract the
                             * first part of the DROP which includes the
                             * object type.  Most of the time this matches
                             * te->desc, so search for that; however for the
                             * different kinds of CONSTRAINTs, we know to
                             * search for hardcoded "DROP CONSTRAINT" instead.
                             */
                            if (strcmp(te->desc, "DEFAULT") == 0 ||
                                strcmp(te->desc, "DATABASE PROPERTIES") == 0 ||
                                strncmp(dropStmt, "CREATE OR REPLACE VIEW", 22) == 0)
                                appendPQExpBufferStr(ftStmt, dropStmt);
                            else
                            {
                                char        buffer[40];
                                char       *mark;
 
                                if (strcmp(te->desc, "CONSTRAINT") == 0 ||
                                    strcmp(te->desc, "CHECK CONSTRAINT") == 0 ||
                                    strcmp(te->desc, "FK CONSTRAINT") == 0)
                                    strcpy(buffer, "DROP CONSTRAINT");
                                else
                                    snprintf(buffer, sizeof(buffer), "DROP %s",
                                             te->desc);
 
                                mark = strstr(dropStmt, buffer);
 
                                if (mark)
                                {
                                    *mark = '\0';
                                    appendPQExpBuffer(ftStmt, "%s%s IF EXISTS%s",
                                                      dropStmt, buffer,
                                                      mark + strlen(buffer));
                                }
                                else
                                {
                                    /* complain and emit unmodified command */
                                    pg_log_warning("could not find where to insert IF EXISTS in statement \"%s\"",
                                                   dropStmtOrig);
                                    appendPQExpBufferStr(ftStmt, dropStmt);
                                }
                            }
 
                            ahprintf(AH, "%s", ftStmt->data);
 
                            destroyPQExpBuffer(ftStmt);
                            pg_free(dropStmtOrig);
                        }
                    }
                }
 
                /*
                 * In --transaction-size mode, re-establish the transaction
                 * block if needed; otherwise, commit after every N drops.
                 */
                if (ropt->txn_size > 0)
                {
                    if (not_allowed_in_txn)
                    {
                        if (AH->connection)
                            StartTransaction(AHX);
                        else
                            ahprintf(AH, "BEGIN;\n");
                        AH->txnCount = 0;
                    }
                    else if (++AH->txnCount >= ropt->txn_size)
                    {
                        if (AH->connection)
                        {
                            CommitTransaction(AHX);
                            StartTransaction(AHX);
                        }
                        else
                            ahprintf(AH, "COMMIT;\nBEGIN;\n");
                        AH->txnCount = 0;
                    }
                }
            }
        }
 
        /*
         * _selectOutputSchema may have set currSchema to reflect the effect
         * of a "SET search_path" command it emitted.  However, by now we may
         * have dropped that schema; or it might not have existed in the first
         * place.  In either case the effective value of search_path will not
         * be what we think.  Forcibly reset currSchema so that we will
         * re-establish the search_path setting when needed (after creating
         * the schema).
         *
         * If we treated users as pg_dump'able objects then we'd need to reset
         * currUser here too.
         */
        free(AH->currSchema);
        AH->currSchema = NULL;
    }
 
    if (parallel_mode)
    {
        /*
         * In parallel mode, turn control over to the parallel-restore logic.
         */
        ParallelState *pstate;
        TocEntry    pending_list;
 
        /* The archive format module may need some setup for this */
        if (AH->PrepParallelRestorePtr)
            AH->PrepParallelRestorePtr(AH);
 
        pending_list_header_init(&pending_list);
 
        /* This runs PRE_DATA items and then disconnects from the database */
        restore_toc_entries_prefork(AH, &pending_list);
        Assert(AH->connection == NULL);
 
        /* ParallelBackupStart() will actually fork the processes */
        pstate = ParallelBackupStart(AH);
        restore_toc_entries_parallel(AH, pstate, &pending_list);
        ParallelBackupEnd(AH, pstate);
 
        /* reconnect the leader and see if we missed something */
        restore_toc_entries_postfork(AH, &pending_list);
        Assert(AH->connection != NULL);
    }
    else
    {
        /*
         * In serial mode, process everything in three phases: normal items,
         * then ACLs, then post-ACL items.  We might be able to skip one or
         * both extra phases in some cases, eg data-only restores.
         */
        bool        haveACL = false;
        bool        havePostACL = false;
 
        for (te = AH->toc->next; te != AH->toc; te = te->next)
        {
            if ((te->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS)) == 0)
                continue;       /* ignore if not to be dumped at all */
 
            switch (_tocEntryRestorePass(te))
            {
                case RESTORE_PASS_MAIN:
                    (void) restore_toc_entry(AH, te, false);
                    break;
                case RESTORE_PASS_ACL:
                    haveACL = true;
                    break;
                case RESTORE_PASS_POST_ACL:
                    havePostACL = true;
                    break;
            }
        }
 
        if (haveACL)
        {
            for (te = AH->toc->next; te != AH->toc; te = te->next)
            {
                if ((te->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS)) != 0 &&
                    _tocEntryRestorePass(te) == RESTORE_PASS_ACL)
                    (void) restore_toc_entry(AH, te, false);
            }
        }
 
        if (havePostACL)
        {
            for (te = AH->toc->next; te != AH->toc; te = te->next)
            {
                if ((te->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS)) != 0 &&
                    _tocEntryRestorePass(te) == RESTORE_PASS_POST_ACL)
                    (void) restore_toc_entry(AH, te, false);
            }
        }
    }
 
    /*
     * Close out any persistent transaction we may have.  While these two
     * cases are started in different places, we can end both cases here.
     */
    if (ropt->single_txn || ropt->txn_size > 0)
    {
        if (AH->connection)
            CommitTransaction(AHX);
        else
            ahprintf(AH, "COMMIT;\n\n");
    }
 
    if (AH->public.verbose)
        dumpTimestamp(AH, "Completed on", time(NULL));
 
    ahprintf(AH, "--\n-- PostgreSQL database dump complete\n--\n\n");
 
    /*
     * If generating plain-text output, exit restricted mode at the very end
     * of the script. This is not pro forma; in particular, pg_dumpall
     * requires this when transitioning from one database to another.
     */
    if (ropt->restrict_key)
        ahprintf(AH, "\\unrestrict %s\n\n", ropt->restrict_key);
 
    /*
     * Clean up & we're done.
     */
    AH->stage = STAGE_FINALIZING;
 
    if (ropt->filename || ropt->compression_spec.algorithm != PG_COMPRESSION_NONE)
        RestoreOutput(AH, sav);
 
    if (ropt->useDB)
        DisconnectDatabase(&AH->public);
}
 
/*
 * Restore a single TOC item.  Used in both parallel and non-parallel restore;
 * is_parallel is true if we are in a worker child process.
 *
 * Returns 0 normally, but WORKER_CREATE_DONE or WORKER_INHIBIT_DATA if
 * the parallel parent has to make the corresponding status update.
 */
static int
restore_toc_entry(ArchiveHandle *AH, TocEntry *te, bool is_parallel)
{
    RestoreOptions *ropt = AH->public.ropt;
    int         status = WORKER_OK;
    int         reqs;
    bool        defnDumped;
 
    AH->currentTE = te;
 
    /* Dump any relevant dump warnings to stderr */
    if (!ropt->suppressDumpWarnings && strcmp(te->desc, "WARNING") == 0)
    {
        if (ropt->dumpSchema && te->defn != NULL && strlen(te->defn) != 0)
            pg_log_warning("warning from original dump file: %s", te->defn);
        else if (te->copyStmt != NULL && strlen(te->copyStmt) != 0)
            pg_log_warning("warning from original dump file: %s", te->copyStmt);
    }
 
    /* Work out what, if anything, we want from this entry */
    reqs = te->reqs;
 
    defnDumped = false;
 
    /*
     * If it has a schema component that we want, then process that
     */
    if ((reqs & REQ_SCHEMA) != 0)
    {
        bool        object_is_db = false;
 
        /*
         * In --transaction-size mode, must exit our transaction block to
         * create a database or set its properties.
         */
        if (strcmp(te->desc, "DATABASE") == 0 ||
            strcmp(te->desc, "DATABASE PROPERTIES") == 0)
        {
            object_is_db = true;
            if (ropt->txn_size > 0)
            {
                if (AH->connection)
                    CommitTransaction(&AH->public);
                else
                    ahprintf(AH, "COMMIT;\n\n");
            }
        }
 
        /* Show namespace in log message if available */
        if (te->namespace)
            pg_log_info("creating %s \"%s.%s\"",
                        te->desc, te->namespace, te->tag);
        else
            pg_log_info("creating %s \"%s\"",
                        te->desc, te->tag);
 
        _printTocEntry(AH, te, TOC_PREFIX_NONE);
        defnDumped = true;
 
        if (strcmp(te->desc, "TABLE") == 0)
        {
            if (AH->lastErrorTE == te)
            {
                /*
                 * We failed to create the table. If
                 * --no-data-for-failed-tables was given, mark the
                 * corresponding TABLE DATA to be ignored.
                 *
                 * In the parallel case this must be done in the parent, so we
                 * just set the return value.
                 */
                if (ropt->noDataForFailedTables)
                {
                    if (is_parallel)
                        status = WORKER_INHIBIT_DATA;
                    else
                        inhibit_data_for_failed_table(AH, te);
                }
            }
            else
            {
                /*
                 * We created the table successfully.  Mark the corresponding
                 * TABLE DATA for possible truncation.
                 *
                 * In the parallel case this must be done in the parent, so we
                 * just set the return value.
                 */
                if (is_parallel)
                    status = WORKER_CREATE_DONE;
                else
                    mark_create_done(AH, te);
            }
        }
 
        /*
         * If we created a DB, connect to it.  Also, if we changed DB
         * properties, reconnect to ensure that relevant GUC settings are
         * applied to our session.  (That also restarts the transaction block
         * in --transaction-size mode.)
         */
        if (object_is_db)
        {
            pg_log_info("connecting to new database \"%s\"", te->tag);
            _reconnectToDB(AH, te->tag);
        }
    }
 
    /*
     * If it has a data component that we want, then process that
     */
    if ((reqs & REQ_DATA) != 0)
    {
        /*
         * hadDumper will be set if there is genuine data component for this
         * node. Otherwise, we need to check the defn field for statements
         * that need to be executed in data-only restores.
         */
        if (te->hadDumper)
        {
            /*
             * If we can output the data, then restore it.
             */
            if (AH->PrintTocDataPtr != NULL)
            {
                _printTocEntry(AH, te, TOC_PREFIX_DATA);
 
                if (strcmp(te->desc, "BLOBS") == 0 ||
                    strcmp(te->desc, "BLOB COMMENTS") == 0)
                {
                    pg_log_info("processing %s", te->desc);
 
                    _selectOutputSchema(AH, "pg_catalog");
 
                    /* Send BLOB COMMENTS data to ExecuteSimpleCommands() */
                    if (strcmp(te->desc, "BLOB COMMENTS") == 0)
                        AH->outputKind = OUTPUT_OTHERDATA;
 
                    AH->PrintTocDataPtr(AH, te);
 
                    AH->outputKind = OUTPUT_SQLCMDS;
                }
                else
                {
                    bool        use_truncate;
 
                    _disableTriggersIfNecessary(AH, te);
 
                    /* Select owner and schema as necessary */
                    _becomeOwner(AH, te);
                    _selectOutputSchema(AH, te->namespace);
 
                    pg_log_info("processing data for table \"%s.%s\"",
                                te->namespace, te->tag);
 
                    /*
                     * In parallel restore, if we created the table earlier in
                     * this run (so that we know it is empty) and we are not
                     * restoring a load-via-partition-root data item then we
                     * wrap the COPY in a transaction and precede it with a
                     * TRUNCATE.  If wal_level is set to minimal this prevents
                     * WAL-logging the COPY.  This obtains a speedup similar
                     * to that from using single_txn mode in non-parallel
                     * restores.
                     *
                     * We mustn't do this for load-via-partition-root cases
                     * because some data might get moved across partition
                     * boundaries, risking deadlock and/or loss of previously
                     * loaded data.  (We assume that all partitions of a
                     * partitioned table will be treated the same way.)
                     */
                    use_truncate = is_parallel && te->created &&
                        !is_load_via_partition_root(te);
 
                    if (use_truncate)
                    {
                        /*
                         * Parallel restore is always talking directly to a
                         * server, so no need to see if we should issue BEGIN.
                         */
                        StartTransaction(&AH->public);
 
                        /*
                         * Issue TRUNCATE with ONLY so that child tables are
                         * not wiped.
                         */
                        ahprintf(AH, "TRUNCATE TABLE ONLY %s;\n\n",
                                 fmtQualifiedId(te->namespace, te->tag));
                    }
 
                    /*
                     * If we have a copy statement, use it.
                     */
                    if (te->copyStmt && strlen(te->copyStmt) > 0)
                    {
                        ahprintf(AH, "%s", te->copyStmt);
                        AH->outputKind = OUTPUT_COPYDATA;
                    }
                    else
                        AH->outputKind = OUTPUT_OTHERDATA;
 
                    AH->PrintTocDataPtr(AH, te);
 
                    /*
                     * Terminate COPY if needed.
                     */
                    if (AH->outputKind == OUTPUT_COPYDATA &&
                        RestoringToDB(AH))
                        EndDBCopyMode(&AH->public, te->tag);
                    AH->outputKind = OUTPUT_SQLCMDS;
 
                    /* close out the transaction started above */
                    if (use_truncate)
                        CommitTransaction(&AH->public);
 
                    _enableTriggersIfNecessary(AH, te);
                }
            }
        }
        else if (!defnDumped)
        {
            /* If we haven't already dumped the defn part, do so now */
            pg_log_info("executing %s %s", te->desc, te->tag);
            _printTocEntry(AH, te, TOC_PREFIX_NONE);
        }
    }
 
    /*
     * If it has a statistics component that we want, then process that
     */
    if ((reqs & REQ_STATS) != 0)
        _printTocEntry(AH, te, TOC_PREFIX_STATS);
 
    /*
     * If we emitted anything for this TOC entry, that counts as one action
     * against the transaction-size limit.  Commit if it's time to.
     */
    if ((reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS)) != 0 && ropt->txn_size > 0)
    {
        if (++AH->txnCount >= ropt->txn_size)
        {
            if (AH->connection)
            {
                CommitTransaction(&AH->public);
                StartTransaction(&AH->public);
            }
            else
                ahprintf(AH, "COMMIT;\nBEGIN;\n\n");
            AH->txnCount = 0;
        }
    }
 
    if (AH->public.n_errors > 0 && status == WORKER_OK)
        status = WORKER_IGNORED_ERRORS;
 
    return status;
}
 
/*
 * Allocate a new RestoreOptions block.
 * This is mainly so we can initialize it, but also for future expansion,
 */
RestoreOptions *
NewRestoreOptions(void)
{
    RestoreOptions *opts;
 
    opts = (RestoreOptions *) pg_malloc0(sizeof(RestoreOptions));
 
    /* set any fields that shouldn't default to zeroes */
    opts->format = archUnknown;
    opts->cparams.promptPassword = TRI_DEFAULT;
    opts->dumpSections = DUMP_UNSECTIONED;
    opts->compression_spec.algorithm = PG_COMPRESSION_NONE;
    opts->compression_spec.level = 0;
    opts->dumpSchema = true;
    opts->dumpData = true;
    opts->dumpStatistics = true;
 
    return opts;
}
 
static void
_disableTriggersIfNecessary(ArchiveHandle *AH, TocEntry *te)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    /* This hack is only needed in a data-only restore */
    if (ropt->dumpSchema || !ropt->disable_triggers)
        return;
 
    pg_log_info("disabling triggers for %s", te->tag);
 
    /*
     * Become superuser if possible, since they are the only ones who can
     * disable constraint triggers.  If -S was not given, assume the initial
     * user identity is a superuser.  (XXX would it be better to become the
     * table owner?)
     */
    _becomeUser(AH, ropt->superuser);
 
    /*
     * Disable them.
     */
    ahprintf(AH, "ALTER TABLE %s DISABLE TRIGGER ALL;\n\n",
             fmtQualifiedId(te->namespace, te->tag));
}
 
static void
_enableTriggersIfNecessary(ArchiveHandle *AH, TocEntry *te)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    /* This hack is only needed in a data-only restore */
    if (ropt->dumpSchema || !ropt->disable_triggers)
        return;
 
    pg_log_info("enabling triggers for %s", te->tag);
 
    /*
     * Become superuser if possible, since they are the only ones who can
     * disable constraint triggers.  If -S was not given, assume the initial
     * user identity is a superuser.  (XXX would it be better to become the
     * table owner?)
     */
    _becomeUser(AH, ropt->superuser);
 
    /*
     * Enable them.
     */
    ahprintf(AH, "ALTER TABLE %s ENABLE TRIGGER ALL;\n\n",
             fmtQualifiedId(te->namespace, te->tag));
}
 
/*
 * Detect whether a TABLE DATA TOC item is performing "load via partition
 * root", that is the target table is an ancestor partition rather than the
 * table the TOC item is nominally for.
 *
 * In newer archive files this can be detected by checking for a special
 * comment placed in te->defn.  In older files we have to fall back to seeing
 * if the COPY statement targets the named table or some other one.  This
 * will not work for data dumped as INSERT commands, so we could give a false
 * negative in that case; fortunately, that's a rarely-used option.
 */
static bool
is_load_via_partition_root(TocEntry *te)
{
    if (te->defn &&
        strncmp(te->defn, "-- load via partition root ", 27) == 0)
        return true;
    if (te->copyStmt && *te->copyStmt)
    {
        PQExpBuffer copyStmt = createPQExpBuffer();
        bool        result;
 
        /*
         * Build the initial part of the COPY as it would appear if the
         * nominal target table is the actual target.  If we see anything
         * else, it must be a load-via-partition-root case.
         */
        appendPQExpBuffer(copyStmt, "COPY %s ",
                          fmtQualifiedId(te->namespace, te->tag));
        result = strncmp(te->copyStmt, copyStmt->data, copyStmt->len) != 0;
        destroyPQExpBuffer(copyStmt);
        return result;
    }
    /* Assume it's not load-via-partition-root */
    return false;
}
 
/*
 * This is a routine that is part of the dumper interface, hence the 'Archive*' parameter.
 */
 
/* Public */
void
WriteData(Archive *AHX, const void *data, size_t dLen)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
 
    if (!AH->currToc)
        pg_fatal("internal error -- WriteData cannot be called outside the context of a DataDumper routine");
 
    AH->WriteDataPtr(AH, data, dLen);
}
 
/*
 * Create a new TOC entry. The TOC was designed as a TOC, but is now the
 * repository for all metadata. But the name has stuck.
 *
 * The new entry is added to the Archive's TOC list.  Most callers can ignore
 * the result value because nothing else need be done, but a few want to
 * manipulate the TOC entry further.
 */
 
/* Public */
TocEntry *
ArchiveEntry(Archive *AHX, CatalogId catalogId, DumpId dumpId,
             ArchiveOpts *opts)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
    TocEntry   *newToc;
 
    newToc = (TocEntry *) pg_malloc0(sizeof(TocEntry));
 
    AH->tocCount++;
    if (dumpId > AH->maxDumpId)
        AH->maxDumpId = dumpId;
 
    newToc->prev = AH->toc->prev;
    newToc->next = AH->toc;
    AH->toc->prev->next = newToc;
    AH->toc->prev = newToc;
 
    newToc->catalogId = catalogId;
    newToc->dumpId = dumpId;
    newToc->section = opts->section;
 
    newToc->tag = pg_strdup(opts->tag);
    newToc->namespace = opts->namespace ? pg_strdup(opts->namespace) : NULL;
    newToc->tablespace = opts->tablespace ? pg_strdup(opts->tablespace) : NULL;
    newToc->tableam = opts->tableam ? pg_strdup(opts->tableam) : NULL;
    newToc->relkind = opts->relkind;
    newToc->owner = opts->owner ? pg_strdup(opts->owner) : NULL;
    newToc->desc = pg_strdup(opts->description);
    newToc->defn = opts->createStmt ? pg_strdup(opts->createStmt) : NULL;
    newToc->dropStmt = opts->dropStmt ? pg_strdup(opts->dropStmt) : NULL;
    newToc->copyStmt = opts->copyStmt ? pg_strdup(opts->copyStmt) : NULL;
 
    if (opts->nDeps > 0)
    {
        newToc->dependencies = (DumpId *) pg_malloc(opts->nDeps * sizeof(DumpId));
        memcpy(newToc->dependencies, opts->deps, opts->nDeps * sizeof(DumpId));
        newToc->nDeps = opts->nDeps;
    }
    else
    {
        newToc->dependencies = NULL;
        newToc->nDeps = 0;
    }
 
    newToc->dataDumper = opts->dumpFn;
    newToc->dataDumperArg = opts->dumpArg;
    newToc->hadDumper = opts->dumpFn ? true : false;
 
    newToc->defnDumper = opts->defnFn;
    newToc->defnDumperArg = opts->defnArg;
 
    newToc->formatData = NULL;
    newToc->dataLength = 0;
 
    if (AH->ArchiveEntryPtr != NULL)
        AH->ArchiveEntryPtr(AH, newToc);
 
    return newToc;
}
 
/* Public */
void
PrintTOCSummary(Archive *AHX)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
    RestoreOptions *ropt = AH->public.ropt;
    TocEntry   *te;
    pg_compress_specification out_compression_spec = {0};
    teSection   curSection;
    CompressFileHandle *sav;
    const char *fmtName;
    char        stamp_str[64];
 
    /* TOC is always uncompressed */
    out_compression_spec.algorithm = PG_COMPRESSION_NONE;
 
    sav = SaveOutput(AH);
    if (ropt->filename)
        SetOutput(AH, ropt->filename, out_compression_spec);
 
    if (strftime(stamp_str, sizeof(stamp_str), PGDUMP_STRFTIME_FMT,
                 localtime(&AH->createDate)) == 0)
        strcpy(stamp_str, "[unknown]");
 
    ahprintf(AH, ";\n; Archive created at %s\n", stamp_str);
    ahprintf(AH, ";     dbname: %s\n;     TOC Entries: %d\n;     Compression: %s\n",
             sanitize_line(AH->archdbname, false),
             AH->tocCount,
             get_compress_algorithm_name(AH->compression_spec.algorithm));
 
    switch (AH->format)
    {
        case archCustom:
            fmtName = "CUSTOM";
            break;
        case archDirectory:
            fmtName = "DIRECTORY";
            break;
        case archTar:
            fmtName = "TAR";
            break;
        default:
            fmtName = "UNKNOWN";
    }
 
    ahprintf(AH, ";     Dump Version: %d.%d-%d\n",
             ARCHIVE_MAJOR(AH->version), ARCHIVE_MINOR(AH->version), ARCHIVE_REV(AH->version));
    ahprintf(AH, ";     Format: %s\n", fmtName);
    ahprintf(AH, ";     Integer: %zu bytes\n", AH->intSize);
    ahprintf(AH, ";     Offset: %zu bytes\n", AH->offSize);
    if (AH->archiveRemoteVersion)
        ahprintf(AH, ";     Dumped from database version: %s\n",
                 AH->archiveRemoteVersion);
    if (AH->archiveDumpVersion)
        ahprintf(AH, ";     Dumped by pg_dump version: %s\n",
                 AH->archiveDumpVersion);
 
    ahprintf(AH, ";\n;\n; Selected TOC Entries:\n;\n");
 
    curSection = SECTION_PRE_DATA;
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        /* This bit must match ProcessArchiveRestoreOptions' marking logic */
        if (te->section != SECTION_NONE)
            curSection = te->section;
        te->reqs = _tocEntryRequired(te, curSection, AH);
        /* Now, should we print it? */
        if (ropt->verbose ||
            (te->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS)) != 0)
        {
            char       *sanitized_name;
            char       *sanitized_schema;
            char       *sanitized_owner;
 
            /*
             */
            sanitized_name = sanitize_line(te->tag, false);
            sanitized_schema = sanitize_line(te->namespace, true);
            sanitized_owner = sanitize_line(te->owner, false);
 
            ahprintf(AH, "%d; %u %u %s %s %s %s\n", te->dumpId,
                     te->catalogId.tableoid, te->catalogId.oid,
                     te->desc, sanitized_schema, sanitized_name,
                     sanitized_owner);
 
            free(sanitized_name);
            free(sanitized_schema);
            free(sanitized_owner);
        }
        if (ropt->verbose && te->nDeps > 0)
        {
            int         i;
 
            ahprintf(AH, ";\tdepends on:");
            for (i = 0; i < te->nDeps; i++)
                ahprintf(AH, " %d", te->dependencies[i]);
            ahprintf(AH, "\n");
        }
    }
 
    /* Enforce strict names checking */
    if (ropt->strict_names)
        StrictNamesCheck(ropt);
 
    if (ropt->filename)
        RestoreOutput(AH, sav);
}
 
/***********
 * Large Object Archival
 ***********/
 
/* Called by a dumper to signal start of a LO */
int
StartLO(Archive *AHX, Oid oid)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
 
    if (!AH->StartLOPtr)
        pg_fatal("large-object output not supported in chosen format");
 
    AH->StartLOPtr(AH, AH->currToc, oid);
 
    return 1;
}
 
/* Called by a dumper to signal end of a LO */
int
EndLO(Archive *AHX, Oid oid)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
 
    if (AH->EndLOPtr)
        AH->EndLOPtr(AH, AH->currToc, oid);
 
    return 1;
}
 
/**********
 * Large Object Restoration
 **********/
 
/*
 * Called by a format handler before a group of LOs is restored
 */
void
StartRestoreLOs(ArchiveHandle *AH)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    /*
     * LOs must be restored within a transaction block, since we need the LO
     * handle to stay open while we write it.  Establish a transaction unless
     * there's one being used globally.
     */
    if (!(ropt->single_txn || ropt->txn_size > 0))
    {
        if (AH->connection)
            StartTransaction(&AH->public);
        else
            ahprintf(AH, "BEGIN;\n\n");
    }
 
    AH->loCount = 0;
}
 
/*
 * Called by a format handler after a group of LOs is restored
 */
void
EndRestoreLOs(ArchiveHandle *AH)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    if (!(ropt->single_txn || ropt->txn_size > 0))
    {
        if (AH->connection)
            CommitTransaction(&AH->public);
        else
            ahprintf(AH, "COMMIT;\n\n");
    }
 
    pg_log_info(ngettext("restored %d large object",
                         "restored %d large objects",
                         AH->loCount),
                AH->loCount);
}
 
 
/*
 * Called by a format handler to initiate restoration of a LO
 */
void
StartRestoreLO(ArchiveHandle *AH, Oid oid, bool drop)
{
    bool        old_lo_style = (AH->version < K_VERS_1_12);
    Oid         loOid;
 
    AH->loCount++;
 
    /* Initialize the LO Buffer */
    if (AH->lo_buf == NULL)
    {
        /* First time through (in this process) so allocate the buffer */
        AH->lo_buf_size = LOBBUFSIZE;
        AH->lo_buf = pg_malloc(LOBBUFSIZE);
    }
    AH->lo_buf_used = 0;
 
    pg_log_info("restoring large object with OID %u", oid);
 
    /* With an old archive we must do drop and create logic here */
    if (old_lo_style && drop)
        DropLOIfExists(AH, oid);
 
    if (AH->connection)
    {
        if (old_lo_style)
        {
            loOid = lo_create(AH->connection, oid);
            if (loOid == 0 || loOid != oid)
                pg_fatal("could not create large object %u: %s",
                         oid, PQerrorMessage(AH->connection));
        }
        AH->loFd = lo_open(AH->connection, oid, INV_WRITE);
        if (AH->loFd == -1)
            pg_fatal("could not open large object %u: %s",
                     oid, PQerrorMessage(AH->connection));
    }
    else
    {
        if (old_lo_style)
            ahprintf(AH, "SELECT pg_catalog.lo_open(pg_catalog.lo_create('%u'), %d);\n",
                     oid, INV_WRITE);
        else
            ahprintf(AH, "SELECT pg_catalog.lo_open('%u', %d);\n",
                     oid, INV_WRITE);
    }
 
    AH->writingLO = true;
}
 
void
EndRestoreLO(ArchiveHandle *AH, Oid oid)
{
    if (AH->lo_buf_used > 0)
    {
        /* Write remaining bytes from the LO buffer */
        dump_lo_buf(AH);
    }
 
    AH->writingLO = false;
 
    if (AH->connection)
    {
        lo_close(AH->connection, AH->loFd);
        AH->loFd = -1;
    }
    else
    {
        ahprintf(AH, "SELECT pg_catalog.lo_close(0);\n\n");
    }
}
 
/***********
 * Sorting and Reordering
 ***********/
 
void
SortTocFromFile(Archive *AHX)
{
    ArchiveHandle *AH = (ArchiveHandle *) AHX;
    RestoreOptions *ropt = AH->public.ropt;
    FILE       *fh;
    StringInfoData linebuf;
 
    /* Allocate space for the 'wanted' array, and init it */
    ropt->idWanted = (bool *) pg_malloc0(sizeof(bool) * AH->maxDumpId);
 
    /* Setup the file */
    fh = fopen(ropt->tocFile, PG_BINARY_R);
    if (!fh)
        pg_fatal("could not open TOC file \"%s\": %m", ropt->tocFile);
 
    initStringInfo(&linebuf);
 
    while (pg_get_line_buf(fh, &linebuf))
    {
        char       *cmnt;
        char       *endptr;
        DumpId      id;
        TocEntry   *te;
 
        /* Truncate line at comment, if any */
        cmnt = strchr(linebuf.data, ';');
        if (cmnt != NULL)
        {
            cmnt[0] = '\0';
            linebuf.len = cmnt - linebuf.data;
        }
 
        /* Ignore if all blank */
        if (strspn(linebuf.data, " \t\r\n") == linebuf.len)
            continue;
 
        /* Get an ID, check it's valid and not already seen */
        id = strtol(linebuf.data, &endptr, 10);
        if (endptr == linebuf.data || id <= 0 || id > AH->maxDumpId ||
            ropt->idWanted[id - 1])
        {
            pg_log_warning("line ignored: %s", linebuf.data);
            continue;
        }
 
        /* Find TOC entry */
        te = getTocEntryByDumpId(AH, id);
        if (!te)
            pg_fatal("could not find entry for ID %d",
                     id);
 
        /* Mark it wanted */
        ropt->idWanted[id - 1] = true;
 
        /*
         * Move each item to the end of the list as it is selected, so that
         * they are placed in the desired order.  Any unwanted items will end
         * up at the front of the list, which may seem unintuitive but it's
         * what we need.  In an ordinary serial restore that makes no
         * difference, but in a parallel restore we need to mark unrestored
         * items' dependencies as satisfied before we start examining
         * restorable items.  Otherwise they could have surprising
         * side-effects on the order in which restorable items actually get
         * restored.
         */
        _moveBefore(AH->toc, te);
    }
 
    pg_free(linebuf.data);
 
    if (fclose(fh) != 0)
        pg_fatal("could not close TOC file: %m");
}
 
/**********************
 * Convenience functions that look like standard IO functions
 * for writing data when in dump mode.
 **********************/
 
/* Public */
void
archputs(const char *s, Archive *AH)
{
    WriteData(AH, s, strlen(s));
}
 
/* Public */
int
archprintf(Archive *AH, const char *fmt,...)
{
    int         save_errno = errno;
    char       *p;
    size_t      len = 128;      /* initial assumption about buffer size */
    size_t      cnt;
 
    for (;;)
    {
        va_list     args;
 
        /* Allocate work buffer. */
        p = (char *) pg_malloc(len);
 
        /* Try to format the data. */
        errno = save_errno;
        va_start(args, fmt);
        cnt = pvsnprintf(p, len, fmt, args);
        va_end(args);
 
        if (cnt < len)
            break;              /* success */
 
        /* Release buffer and loop around to try again with larger len. */
        free(p);
        len = cnt;
    }
 
    WriteData(AH, p, cnt);
    free(p);
    return (int) cnt;
}
 
 
/*******************************
 * Stuff below here should be 'private' to the archiver routines
 *******************************/
 
static void
SetOutput(ArchiveHandle *AH, const char *filename,
          const pg_compress_specification compression_spec)
{
    CompressFileHandle *CFH;
    const char *mode;
    int         fn = -1;
 
    if (filename)
    {
        if (strcmp(filename, "-") == 0)
            fn = fileno(stdout);
    }
    else if (AH->FH)
        fn = fileno(AH->FH);
    else if (AH->fSpec)
    {
        filename = AH->fSpec;
    }
    else
        fn = fileno(stdout);
 
    if (AH->mode == archModeAppend)
        mode = PG_BINARY_A;
    else
        mode = PG_BINARY_W;
 
    CFH = InitCompressFileHandle(compression_spec);
 
    if (!CFH->open_func(filename, fn, mode, CFH))
    {
        if (filename)
            pg_fatal("could not open output file \"%s\": %m", filename);
        else
            pg_fatal("could not open output file: %m");
    }
 
    AH->OF = CFH;
}
 
static CompressFileHandle *
SaveOutput(ArchiveHandle *AH)
{
    return (CompressFileHandle *) AH->OF;
}
 
static void
RestoreOutput(ArchiveHandle *AH, CompressFileHandle *savedOutput)
{
    errno = 0;
    if (!EndCompressFileHandle(AH->OF))
        pg_fatal("could not close output file: %m");
 
    AH->OF = savedOutput;
}
 
 
 
/*
 *  Print formatted text to the output file (usually stdout).
 */
int
ahprintf(ArchiveHandle *AH, const char *fmt,...)
{
    int         save_errno = errno;
    char       *p;
    size_t      len = 128;      /* initial assumption about buffer size */
    size_t      cnt;
 
    for (;;)
    {
        va_list     args;
 
        /* Allocate work buffer. */
        p = (char *) pg_malloc(len);
 
        /* Try to format the data. */
        errno = save_errno;
        va_start(args, fmt);
        cnt = pvsnprintf(p, len, fmt, args);
        va_end(args);
 
        if (cnt < len)
            break;              /* success */
 
        /* Release buffer and loop around to try again with larger len. */
        free(p);
        len = cnt;
    }
 
    ahwrite(p, 1, cnt, AH);
    free(p);
    return (int) cnt;
}
 
/*
 * Single place for logic which says 'We are restoring to a direct DB connection'.
 */
static int
RestoringToDB(ArchiveHandle *AH)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    return (ropt && ropt->useDB && AH->connection);
}
 
/*
 * Dump the current contents of the LO data buffer while writing a LO
 */
static void
dump_lo_buf(ArchiveHandle *AH)
{
    if (AH->connection)
    {
        int         res;
 
        res = lo_write(AH->connection, AH->loFd, AH->lo_buf, AH->lo_buf_used);
        pg_log_debug(ngettext("wrote %zu byte of large object data (result = %d)",
                              "wrote %zu bytes of large object data (result = %d)",
                              AH->lo_buf_used),
                     AH->lo_buf_used, res);
        /* We assume there are no short writes, only errors */
        if (res != AH->lo_buf_used)
            warn_or_exit_horribly(AH, "could not write to large object: %s",
                                  PQerrorMessage(AH->connection));
    }
    else
    {
        PQExpBuffer buf = createPQExpBuffer();
 
        appendByteaLiteralAHX(buf,
                              (const unsigned char *) AH->lo_buf,
                              AH->lo_buf_used,
                              AH);
 
        /* Hack: turn off writingLO so ahwrite doesn't recurse to here */
        AH->writingLO = false;
        ahprintf(AH, "SELECT pg_catalog.lowrite(0, %s);\n", buf->data);
        AH->writingLO = true;
 
        destroyPQExpBuffer(buf);
    }
    AH->lo_buf_used = 0;
}
 
 
/*
 *  Write buffer to the output file (usually stdout). This is used for
 *  outputting 'restore' scripts etc. It is even possible for an archive
 *  format to create a custom output routine to 'fake' a restore if it
 *  wants to generate a script (see TAR output).
 */
void
ahwrite(const void *ptr, size_t size, size_t nmemb, ArchiveHandle *AH)
{
    int         bytes_written = 0;
 
    if (AH->writingLO)
    {
        size_t      remaining = size * nmemb;
 
        while (AH->lo_buf_used + remaining > AH->lo_buf_size)
        {
            size_t      avail = AH->lo_buf_size - AH->lo_buf_used;
 
            memcpy((char *) AH->lo_buf + AH->lo_buf_used, ptr, avail);
            ptr = (const char *) ptr + avail;
            remaining -= avail;
            AH->lo_buf_used += avail;
            dump_lo_buf(AH);
        }
 
        memcpy((char *) AH->lo_buf + AH->lo_buf_used, ptr, remaining);
        AH->lo_buf_used += remaining;
 
        bytes_written = size * nmemb;
    }
    else if (AH->CustomOutPtr)
        bytes_written = AH->CustomOutPtr(AH, ptr, size * nmemb);
 
    /*
     * If we're doing a restore, and it's direct to DB, and we're connected
     * then send it to the DB.
     */
    else if (RestoringToDB(AH))
        bytes_written = ExecuteSqlCommandBuf(&AH->public, (const char *) ptr, size * nmemb);
    else
    {
        CompressFileHandle *CFH = (CompressFileHandle *) AH->OF;
 
        CFH->write_func(ptr, size * nmemb, CFH);
        bytes_written = size * nmemb;
    }
 
    if (bytes_written != size * nmemb)
        WRITE_ERROR_EXIT;
}
 
/* on some error, we may decide to go on... */
void
warn_or_exit_horribly(ArchiveHandle *AH, const char *fmt,...)
{
    va_list     ap;
 
    switch (AH->stage)
    {
 
        case STAGE_NONE:
            /* Do nothing special */
            break;
 
        case STAGE_INITIALIZING:
            if (AH->stage != AH->lastErrorStage)
                pg_log_info("while INITIALIZING:");
            break;
 
        case STAGE_PROCESSING:
            if (AH->stage != AH->lastErrorStage)
                pg_log_info("while PROCESSING TOC:");
            break;
 
        case STAGE_FINALIZING:
            if (AH->stage != AH->lastErrorStage)
                pg_log_info("while FINALIZING:");
            break;
    }
    if (AH->currentTE != NULL && AH->currentTE != AH->lastErrorTE)
    {
        pg_log_info("from TOC entry %d; %u %u %s %s %s",
                    AH->currentTE->dumpId,
                    AH->currentTE->catalogId.tableoid,
                    AH->currentTE->catalogId.oid,
                    AH->currentTE->desc ? AH->currentTE->desc : "(no desc)",
                    AH->currentTE->tag ? AH->currentTE->tag : "(no tag)",
                    AH->currentTE->owner ? AH->currentTE->owner : "(no owner)");
    }
    AH->lastErrorStage = AH->stage;
    AH->lastErrorTE = AH->currentTE;
 
    va_start(ap, fmt);
    pg_log_generic_v(PG_LOG_ERROR, PG_LOG_PRIMARY, fmt, ap);
    va_end(ap);
 
    if (AH->public.exit_on_error)
        exit_nicely(1);
    else
        AH->public.n_errors++;
}
 
#ifdef NOT_USED
 
static void
_moveAfter(ArchiveHandle *AH, TocEntry *pos, TocEntry *te)
{
    /* Unlink te from list */
    te->prev->next = te->next;
    te->next->prev = te->prev;
 
    /* and insert it after "pos" */
    te->prev = pos;
    te->next = pos->next;
    pos->next->prev = te;
    pos->next = te;
}
#endif
 
static void
_moveBefore(TocEntry *pos, TocEntry *te)
{
    /* Unlink te from list */
    te->prev->next = te->next;
    te->next->prev = te->prev;
 
    /* and insert it before "pos" */
    te->prev = pos->prev;
    te->next = pos;
    pos->prev->next = te;
    pos->prev = te;
}
 
/*
 * Build index arrays for the TOC list
 *
 * This should be invoked only after we have created or read in all the TOC
 * items.
 *
 * The arrays are indexed by dump ID (so entry zero is unused).  Note that the
 * array entries run only up to maxDumpId.  We might see dependency dump IDs
 * beyond that (if the dump was partial); so always check the array bound
 * before trying to touch an array entry.
 */
static void
buildTocEntryArrays(ArchiveHandle *AH)
{
    DumpId      maxDumpId = AH->maxDumpId;
    TocEntry   *te;
 
    AH->tocsByDumpId = (TocEntry **) pg_malloc0((maxDumpId + 1) * sizeof(TocEntry *));
    AH->tableDataId = (DumpId *) pg_malloc0((maxDumpId + 1) * sizeof(DumpId));
 
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        /* this check is purely paranoia, maxDumpId should be correct */
        if (te->dumpId <= 0 || te->dumpId > maxDumpId)
            pg_fatal("bad dumpId");
 
        /* tocsByDumpId indexes all TOCs by their dump ID */
        AH->tocsByDumpId[te->dumpId] = te;
 
        /*
         * tableDataId provides the TABLE DATA item's dump ID for each TABLE
         * TOC entry that has a DATA item.  We compute this by reversing the
         * TABLE DATA item's dependency, knowing that a TABLE DATA item has
         * just one dependency and it is the TABLE item.
         */
        if (strcmp(te->desc, "TABLE DATA") == 0 && te->nDeps > 0)
        {
            DumpId      tableId = te->dependencies[0];
 
            /*
             * The TABLE item might not have been in the archive, if this was
             * a data-only dump; but its dump ID should be less than its data
             * item's dump ID, so there should be a place for it in the array.
             */
            if (tableId <= 0 || tableId > maxDumpId)
                pg_fatal("bad table dumpId for TABLE DATA item");
 
            AH->tableDataId[tableId] = te->dumpId;
        }
    }
}
 
TocEntry *
getTocEntryByDumpId(ArchiveHandle *AH, DumpId id)
{
    /* build index arrays if we didn't already */
    if (AH->tocsByDumpId == NULL)
        buildTocEntryArrays(AH);
 
    if (id > 0 && id <= AH->maxDumpId)
        return AH->tocsByDumpId[id];
 
    return NULL;
}
 
int
TocIDRequired(ArchiveHandle *AH, DumpId id)
{
    TocEntry   *te = getTocEntryByDumpId(AH, id);
 
    if (!te)
        return 0;
 
    return te->reqs;
}
 
size_t
WriteOffset(ArchiveHandle *AH, pgoff_t o, int wasSet)
{
    int         off;
 
    /* Save the flag */
    AH->WriteBytePtr(AH, wasSet);
 
    /* Write out pgoff_t smallest byte first, prevents endian mismatch */
    for (off = 0; off < sizeof(pgoff_t); off++)
    {
        AH->WriteBytePtr(AH, o & 0xFF);
        o >>= 8;
    }
    return sizeof(pgoff_t) + 1;
}
 
int
ReadOffset(ArchiveHandle *AH, pgoff_t *o)
{
    int         i;
    int         off;
    int         offsetFlg;
 
    /* Initialize to zero */
    *o = 0;
 
    /* Check for old version */
    if (AH->version < K_VERS_1_7)
    {
        /* Prior versions wrote offsets using WriteInt */
        i = ReadInt(AH);
        /* -1 means not set */
        if (i < 0)
            return K_OFFSET_POS_NOT_SET;
        else if (i == 0)
            return K_OFFSET_NO_DATA;
 
        /* Cast to pgoff_t because it was written as an int. */
        *o = (pgoff_t) i;
        return K_OFFSET_POS_SET;
    }
 
    /*
     * Read the flag indicating the state of the data pointer. Check if valid
     * and die if not.
     *
     * This used to be handled by a negative or zero pointer, now we use an
     * extra byte specifically for the state.
     */
    offsetFlg = AH->ReadBytePtr(AH) & 0xFF;
 
    switch (offsetFlg)
    {
        case K_OFFSET_POS_NOT_SET:
        case K_OFFSET_NO_DATA:
        case K_OFFSET_POS_SET:
 
            break;
 
        default:
            pg_fatal("unexpected data offset flag %d", offsetFlg);
    }
 
    /*
     * Read the bytes
     */
    for (off = 0; off < AH->offSize; off++)
    {
        if (off < sizeof(pgoff_t))
            *o |= ((pgoff_t) (AH->ReadBytePtr(AH))) << (off * 8);
        else
        {
            if (AH->ReadBytePtr(AH) != 0)
                pg_fatal("file offset in dump file is too large");
        }
    }
 
    return offsetFlg;
}
 
size_t
WriteInt(ArchiveHandle *AH, int i)
{
    int         b;
 
    /*
     * This is a bit yucky, but I don't want to make the binary format very
     * dependent on representation, and not knowing much about it, I write out
     * a sign byte. If you change this, don't forget to change the file
     * version #, and modify ReadInt to read the new format AS WELL AS the old
     * formats.
     */
 
    /* SIGN byte */
    if (i < 0)
    {
        AH->WriteBytePtr(AH, 1);
        i = -i;
    }
    else
        AH->WriteBytePtr(AH, 0);
 
    for (b = 0; b < AH->intSize; b++)
    {
        AH->WriteBytePtr(AH, i & 0xFF);
        i >>= 8;
    }
 
    return AH->intSize + 1;
}
 
int
ReadInt(ArchiveHandle *AH)
{
    int         res = 0;
    int         bv,
                b;
    int         sign = 0;       /* Default positive */
    int         bitShift = 0;
 
    if (AH->version > K_VERS_1_0)
        /* Read a sign byte */
        sign = AH->ReadBytePtr(AH);
 
    for (b = 0; b < AH->intSize; b++)
    {
        bv = AH->ReadBytePtr(AH) & 0xFF;
        if (bv != 0)
            res = res + (bv << bitShift);
        bitShift += 8;
    }
 
    if (sign)
        res = -res;
 
    return res;
}
 
size_t
WriteStr(ArchiveHandle *AH, const char *c)
{
    size_t      res;
 
    if (c)
    {
        int         len = strlen(c);
 
        res = WriteInt(AH, len);
        AH->WriteBufPtr(AH, c, len);
        res += len;
    }
    else
        res = WriteInt(AH, -1);
 
    return res;
}
 
char *
ReadStr(ArchiveHandle *AH)
{
    char       *buf;
    int         l;
 
    l = ReadInt(AH);
    if (l < 0)
        buf = NULL;
    else
    {
        buf = (char *) pg_malloc(l + 1);
        AH->ReadBufPtr(AH, buf, l);
 
        buf[l] = '\0';
    }
 
    return buf;
}
 
static bool
_fileExistsInDirectory(const char *dir, const char *filename)
{
    struct stat st;
    char        buf[MAXPGPATH];
 
    if (snprintf(buf, MAXPGPATH, "%s/%s", dir, filename) >= MAXPGPATH)
        pg_fatal("directory name too long: \"%s\"", dir);
 
    return (stat(buf, &st) == 0 && S_ISREG(st.st_mode));
}
 
static int
_discoverArchiveFormat(ArchiveHandle *AH)
{
    FILE       *fh;
    char        sig[6];         /* More than enough */
    size_t      cnt;
    int         wantClose = 0;
 
    pg_log_debug("attempting to ascertain archive format");
 
    free(AH->lookahead);
 
    AH->readHeader = 0;
    AH->lookaheadSize = 512;
    AH->lookahead = pg_malloc0(512);
    AH->lookaheadLen = 0;
    AH->lookaheadPos = 0;
 
    if (AH->fSpec)
    {
        struct stat st;
 
        wantClose = 1;
 
        /*
         * Check if the specified archive is a directory. If so, check if
         * there's a "toc.dat" (or "toc.dat.{gz,lz4,zst}") file in it.
         */
        if (stat(AH->fSpec, &st) == 0 && S_ISDIR(st.st_mode))
        {
            AH->format = archDirectory;
            if (_fileExistsInDirectory(AH->fSpec, "toc.dat"))
                return AH->format;
#ifdef HAVE_LIBZ
            if (_fileExistsInDirectory(AH->fSpec, "toc.dat.gz"))
                return AH->format;
#endif
#ifdef USE_LZ4
            if (_fileExistsInDirectory(AH->fSpec, "toc.dat.lz4"))
                return AH->format;
#endif
#ifdef USE_ZSTD
            if (_fileExistsInDirectory(AH->fSpec, "toc.dat.zst"))
                return AH->format;
#endif
            pg_fatal("directory \"%s\" does not appear to be a valid archive (\"toc.dat\" does not exist)",
                     AH->fSpec);
            fh = NULL;          /* keep compiler quiet */
        }
        else
        {
            fh = fopen(AH->fSpec, PG_BINARY_R);
            if (!fh)
                pg_fatal("could not open input file \"%s\": %m", AH->fSpec);
        }
    }
    else
    {
        fh = stdin;
        if (!fh)
            pg_fatal("could not open input file: %m");
    }
 
    if ((cnt = fread(sig, 1, 5, fh)) != 5)
    {
        if (ferror(fh))
            pg_fatal("could not read input file: %m");
        else
            pg_fatal("input file is too short (read %zu, expected 5)", cnt);
    }
 
    /* Save it, just in case we need it later */
    memcpy(&AH->lookahead[0], sig, 5);
    AH->lookaheadLen = 5;
 
    if (strncmp(sig, "PGDMP", 5) == 0)
    {
        /* It's custom format, stop here */
        AH->format = archCustom;
        AH->readHeader = 1;
    }
    else
    {
        /*
         * *Maybe* we have a tar archive format file or a text dump ... So,
         * read first 512 byte header...
         */
        cnt = fread(&AH->lookahead[AH->lookaheadLen], 1, 512 - AH->lookaheadLen, fh);
        /* read failure is checked below */
        AH->lookaheadLen += cnt;
 
        if (AH->lookaheadLen >= strlen(TEXT_DUMPALL_HEADER) &&
            (strncmp(AH->lookahead, TEXT_DUMP_HEADER, strlen(TEXT_DUMP_HEADER)) == 0 ||
             strncmp(AH->lookahead, TEXT_DUMPALL_HEADER, strlen(TEXT_DUMPALL_HEADER)) == 0))
        {
            /*
             * looks like it's probably a text format dump. so suggest they
             * try psql
             */
            pg_fatal("input file appears to be a text format dump. Please use psql.");
        }
 
        if (AH->lookaheadLen != 512)
        {
            if (feof(fh))
                pg_fatal("input file does not appear to be a valid archive (too short?)");
            else
                READ_ERROR_EXIT(fh);
        }
 
        if (!isValidTarHeader(AH->lookahead))
            pg_fatal("input file does not appear to be a valid archive");
 
        AH->format = archTar;
    }
 
    /* Close the file if we opened it */
    if (wantClose)
    {
        if (fclose(fh) != 0)
            pg_fatal("could not close input file: %m");
        /* Forget lookahead, since we'll re-read header after re-opening */
        AH->readHeader = 0;
        AH->lookaheadLen = 0;
    }
 
    return AH->format;
}
 
 
/*
 * Allocate an archive handle
 */
static ArchiveHandle *
_allocAH(const char *FileSpec, const ArchiveFormat fmt,
         const pg_compress_specification compression_spec,
         bool dosync, ArchiveMode mode,
         SetupWorkerPtrType setupWorkerPtr, DataDirSyncMethod sync_method)
{
    ArchiveHandle *AH;
    CompressFileHandle *CFH;
    pg_compress_specification out_compress_spec = {0};
 
    pg_log_debug("allocating AH for %s, format %d",
                 FileSpec ? FileSpec : "(stdio)", fmt);
 
    AH = (ArchiveHandle *) pg_malloc0(sizeof(ArchiveHandle));
 
    AH->version = K_VERS_SELF;
 
    /* initialize for backwards compatible string processing */
    AH->public.encoding = 0;    /* PG_SQL_ASCII */
    AH->public.std_strings = false;
 
    /* sql error handling */
    AH->public.exit_on_error = true;
    AH->public.n_errors = 0;
 
    AH->archiveDumpVersion = PG_VERSION;
 
    AH->createDate = time(NULL);
 
    AH->intSize = sizeof(int);
    AH->offSize = sizeof(pgoff_t);
    if (FileSpec)
    {
        AH->fSpec = pg_strdup(FileSpec);
 
        /*
         * Not used; maybe later....
         *
         * AH->workDir = pg_strdup(FileSpec); for(i=strlen(FileSpec) ; i > 0 ;
         * i--) if (AH->workDir[i-1] == '/')
         */
    }
    else
        AH->fSpec = NULL;
 
    AH->currUser = NULL;        /* unknown */
    AH->currSchema = NULL;      /* ditto */
    AH->currTablespace = NULL;  /* ditto */
    AH->currTableAm = NULL;     /* ditto */
 
    AH->toc = (TocEntry *) pg_malloc0(sizeof(TocEntry));
 
    AH->toc->next = AH->toc;
    AH->toc->prev = AH->toc;
 
    AH->mode = mode;
    AH->compression_spec = compression_spec;
    AH->dosync = dosync;
    AH->sync_method = sync_method;
 
    memset(&(AH->sqlparse), 0, sizeof(AH->sqlparse));
 
    /* Open stdout with no compression for AH output handle */
    out_compress_spec.algorithm = PG_COMPRESSION_NONE;
    CFH = InitCompressFileHandle(out_compress_spec);
    if (!CFH->open_func(NULL, fileno(stdout), PG_BINARY_A, CFH))
        pg_fatal("could not open stdout for appending: %m");
    AH->OF = CFH;
 
    /*
     * On Windows, we need to use binary mode to read/write non-text files,
     * which include all archive formats as well as compressed plain text.
     * Force stdin/stdout into binary mode if that is what we are using.
     */
#ifdef WIN32
    if ((fmt != archNull || compression_spec.algorithm != PG_COMPRESSION_NONE) &&
        (AH->fSpec == NULL || strcmp(AH->fSpec, "") == 0))
    {
        if (mode == archModeWrite)
            _setmode(fileno(stdout), O_BINARY);
        else
            _setmode(fileno(stdin), O_BINARY);
    }
#endif
 
    AH->SetupWorkerPtr = setupWorkerPtr;
 
    if (fmt == archUnknown)
        AH->format = _discoverArchiveFormat(AH);
    else
        AH->format = fmt;
 
    switch (AH->format)
    {
        case archCustom:
            InitArchiveFmt_Custom(AH);
            break;
 
        case archNull:
            InitArchiveFmt_Null(AH);
            break;
 
        case archDirectory:
            InitArchiveFmt_Directory(AH);
            break;
 
        case archTar:
            InitArchiveFmt_Tar(AH);
            break;
 
        default:
            pg_fatal("unrecognized file format \"%d\"", AH->format);
    }
 
    return AH;
}
 
/*
 * Write out all data (tables & LOs)
 */
void
WriteDataChunks(ArchiveHandle *AH, ParallelState *pstate)
{
    TocEntry   *te;
 
    if (pstate && pstate->numWorkers > 1)
    {
        /*
         * In parallel mode, this code runs in the leader process.  We
         * construct an array of candidate TEs, then sort it into decreasing
         * size order, then dispatch each TE to a data-transfer worker.  By
         * dumping larger tables first, we avoid getting into a situation
         * where we're down to one job and it's big, losing parallelism.
         */
        TocEntry  **tes;
        int         ntes;
 
        tes = (TocEntry **) pg_malloc(AH->tocCount * sizeof(TocEntry *));
        ntes = 0;
        for (te = AH->toc->next; te != AH->toc; te = te->next)
        {
            /* Consider only TEs with dataDumper functions ... */
            if (!te->dataDumper)
                continue;
            /* ... and ignore ones not enabled for dump */
            if ((te->reqs & REQ_DATA) == 0)
                continue;
 
            tes[ntes++] = te;
        }
 
        if (ntes > 1)
            qsort(tes, ntes, sizeof(TocEntry *), TocEntrySizeCompareQsort);
 
        for (int i = 0; i < ntes; i++)
            DispatchJobForTocEntry(AH, pstate, tes[i], ACT_DUMP,
                                   mark_dump_job_done, NULL);
 
        pg_free(tes);
 
        /* Now wait for workers to finish. */
        WaitForWorkers(AH, pstate, WFW_ALL_IDLE);
    }
    else
    {
        /* Non-parallel mode: just dump all candidate TEs sequentially. */
        for (te = AH->toc->next; te != AH->toc; te = te->next)
        {
            /* Must have same filter conditions as above */
            if (!te->dataDumper)
                continue;
            if ((te->reqs & REQ_DATA) == 0)
                continue;
 
            WriteDataChunksForTocEntry(AH, te);
        }
    }
}
 
 
/*
 * Callback function that's invoked in the leader process after a step has
 * been parallel dumped.
 *
 * We don't need to do anything except check for worker failure.
 */
static void
mark_dump_job_done(ArchiveHandle *AH,
                   TocEntry *te,
                   int status,
                   void *callback_data)
{
    pg_log_info("finished item %d %s %s",
                te->dumpId, te->desc, te->tag);
 
    if (status != 0)
        pg_fatal("worker process failed: exit code %d",
                 status);
}
 
 
void
WriteDataChunksForTocEntry(ArchiveHandle *AH, TocEntry *te)
{
    StartDataPtrType startPtr;
    EndDataPtrType endPtr;
 
    AH->currToc = te;
 
    if (strcmp(te->desc, "BLOBS") == 0)
    {
        startPtr = AH->StartLOsPtr;
        endPtr = AH->EndLOsPtr;
    }
    else
    {
        startPtr = AH->StartDataPtr;
        endPtr = AH->EndDataPtr;
    }
 
    if (startPtr != NULL)
        (*startPtr) (AH, te);
 
    /*
     * The user-provided DataDumper routine needs to call AH->WriteData
     */
    te->dataDumper((Archive *) AH, te->dataDumperArg);
 
    if (endPtr != NULL)
        (*endPtr) (AH, te);
 
    AH->currToc = NULL;
}
 
void
WriteToc(ArchiveHandle *AH)
{
    TocEntry   *te;
    char        workbuf[32];
    int         tocCount;
    int         i;
 
    /* count entries that will actually be dumped */
    tocCount = 0;
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        if ((te->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS | REQ_SPECIAL)) != 0)
            tocCount++;
    }
 
    /* printf("%d TOC Entries to save\n", tocCount); */
 
    WriteInt(AH, tocCount);
 
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        if ((te->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS | REQ_SPECIAL)) == 0)
            continue;
 
        WriteInt(AH, te->dumpId);
        WriteInt(AH, te->dataDumper ? 1 : 0);
 
        /* OID is recorded as a string for historical reasons */
        sprintf(workbuf, "%u", te->catalogId.tableoid);
        WriteStr(AH, workbuf);
        sprintf(workbuf, "%u", te->catalogId.oid);
        WriteStr(AH, workbuf);
 
        WriteStr(AH, te->tag);
        WriteStr(AH, te->desc);
        WriteInt(AH, te->section);
 
        if (te->defnLen)
        {
            /*
             * defnLen should only be set for custom format's second call to
             * WriteToc(), which rewrites the TOC in place to update data
             * offsets.  Instead of calling the defnDumper a second time
             * (which could involve re-executing queries), just skip writing
             * the entry.  While regenerating the definition should
             * theoretically produce the same result as before, it's expensive
             * and feels risky.
             *
             * The custom format only calls WriteToc() a second time if
             * fseeko() is usable (see _CloseArchive() in pg_backup_custom.c),
             * so we can safely use it without checking.  For other formats,
             * we fail because one of our assumptions must no longer hold
             * true.
             *
             * XXX This is a layering violation, but the alternative is an
             * awkward and complicated callback infrastructure for this
             * special case.  This might be worth revisiting in the future.
             */
            if (AH->format != archCustom)
                pg_fatal("unexpected TOC entry in WriteToc(): %d %s %s",
                         te->dumpId, te->desc, te->tag);
 
            if (fseeko(AH->FH, te->defnLen, SEEK_CUR) != 0)
                pg_fatal("error during file seek: %m");
        }
        else if (te->defnDumper)
        {
            char       *defn = te->defnDumper((Archive *) AH, te->defnDumperArg, te);
 
            te->defnLen = WriteStr(AH, defn);
            pg_free(defn);
        }
        else
            WriteStr(AH, te->defn);
 
        WriteStr(AH, te->dropStmt);
        WriteStr(AH, te->copyStmt);
        WriteStr(AH, te->namespace);
        WriteStr(AH, te->tablespace);
        WriteStr(AH, te->tableam);
        WriteInt(AH, te->relkind);
        WriteStr(AH, te->owner);
        WriteStr(AH, "false");
 
        /* Dump list of dependencies */
        for (i = 0; i < te->nDeps; i++)
        {
            sprintf(workbuf, "%d", te->dependencies[i]);
            WriteStr(AH, workbuf);
        }
        WriteStr(AH, NULL);     /* Terminate List */
 
        if (AH->WriteExtraTocPtr)
            AH->WriteExtraTocPtr(AH, te);
    }
}
 
void
ReadToc(ArchiveHandle *AH)
{
    int         i;
    char       *tmp;
    DumpId     *deps;
    int         depIdx;
    int         depSize;
    TocEntry   *te;
    bool        is_supported;
 
    AH->tocCount = ReadInt(AH);
    AH->maxDumpId = 0;
 
    for (i = 0; i < AH->tocCount; i++)
    {
        te = (TocEntry *) pg_malloc0(sizeof(TocEntry));
        te->dumpId = ReadInt(AH);
 
        if (te->dumpId > AH->maxDumpId)
            AH->maxDumpId = te->dumpId;
 
        /* Sanity check */
        if (te->dumpId <= 0)
            pg_fatal("entry ID %d out of range -- perhaps a corrupt TOC",
                     te->dumpId);
 
        te->hadDumper = ReadInt(AH);
 
        if (AH->version >= K_VERS_1_8)
        {
            tmp = ReadStr(AH);
            sscanf(tmp, "%u", &te->catalogId.tableoid);
            free(tmp);
        }
        else
            te->catalogId.tableoid = InvalidOid;
        tmp = ReadStr(AH);
        sscanf(tmp, "%u", &te->catalogId.oid);
        free(tmp);
 
        te->tag = ReadStr(AH);
        te->desc = ReadStr(AH);
 
        if (AH->version >= K_VERS_1_11)
        {
            te->section = ReadInt(AH);
        }
        else
        {
            /*
             * Rules for pre-8.4 archives wherein pg_dump hasn't classified
             * the entries into sections.  This list need not cover entry
             * types added later than 8.4.
             */
            if (strcmp(te->desc, "COMMENT") == 0 ||
                strcmp(te->desc, "ACL") == 0 ||
                strcmp(te->desc, "ACL LANGUAGE") == 0)
                te->section = SECTION_NONE;
            else if (strcmp(te->desc, "TABLE DATA") == 0 ||
                     strcmp(te->desc, "BLOBS") == 0 ||
                     strcmp(te->desc, "BLOB COMMENTS") == 0)
                te->section = SECTION_DATA;
            else if (strcmp(te->desc, "CONSTRAINT") == 0 ||
                     strcmp(te->desc, "CHECK CONSTRAINT") == 0 ||
                     strcmp(te->desc, "FK CONSTRAINT") == 0 ||
                     strcmp(te->desc, "INDEX") == 0 ||
                     strcmp(te->desc, "RULE") == 0 ||
                     strcmp(te->desc, "TRIGGER") == 0)
                te->section = SECTION_POST_DATA;
            else
                te->section = SECTION_PRE_DATA;
        }
 
        te->defn = ReadStr(AH);
        te->dropStmt = ReadStr(AH);
 
        if (AH->version >= K_VERS_1_3)
            te->copyStmt = ReadStr(AH);
 
        if (AH->version >= K_VERS_1_6)
            te->namespace = ReadStr(AH);
 
        if (AH->version >= K_VERS_1_10)
            te->tablespace = ReadStr(AH);
 
        if (AH->version >= K_VERS_1_14)
            te->tableam = ReadStr(AH);
 
        if (AH->version >= K_VERS_1_16)
            te->relkind = ReadInt(AH);
 
        te->owner = ReadStr(AH);
        is_supported = true;
        if (AH->version < K_VERS_1_9)
            is_supported = false;
        else
        {
            tmp = ReadStr(AH);
 
            if (strcmp(tmp, "true") == 0)
                is_supported = false;
 
            free(tmp);
        }
 
        if (!is_supported)
            pg_log_warning("restoring tables WITH OIDS is not supported anymore");
 
        /* Read TOC entry dependencies */
        if (AH->version >= K_VERS_1_5)
        {
            depSize = 100;
            deps = (DumpId *) pg_malloc(sizeof(DumpId) * depSize);
            depIdx = 0;
            for (;;)
            {
                tmp = ReadStr(AH);
                if (!tmp)
                    break;      /* end of list */
                if (depIdx >= depSize)
                {
                    depSize *= 2;
                    deps = (DumpId *) pg_realloc(deps, sizeof(DumpId) * depSize);
                }
                sscanf(tmp, "%d", &deps[depIdx]);
                free(tmp);
                depIdx++;
            }
 
            if (depIdx > 0)     /* We have a non-null entry */
            {
                deps = (DumpId *) pg_realloc(deps, sizeof(DumpId) * depIdx);
                te->dependencies = deps;
                te->nDeps = depIdx;
            }
            else
            {
                free(deps);
                te->dependencies = NULL;
                te->nDeps = 0;
            }
        }
        else
        {
            te->dependencies = NULL;
            te->nDeps = 0;
        }
        te->dataLength = 0;
 
        if (AH->ReadExtraTocPtr)
            AH->ReadExtraTocPtr(AH, te);
 
        pg_log_debug("read TOC entry %d (ID %d) for %s %s",
                     i, te->dumpId, te->desc, te->tag);
 
        /* link completed entry into TOC circular list */
        te->prev = AH->toc->prev;
        AH->toc->prev->next = te;
        AH->toc->prev = te;
        te->next = AH->toc;
 
        /* special processing immediately upon read for some items */
        if (strcmp(te->desc, "ENCODING") == 0)
            processEncodingEntry(AH, te);
        else if (strcmp(te->desc, "STDSTRINGS") == 0)
            processStdStringsEntry(AH, te);
        else if (strcmp(te->desc, "SEARCHPATH") == 0)
            processSearchPathEntry(AH, te);
    }
}
 
static void
processEncodingEntry(ArchiveHandle *AH, TocEntry *te)
{
    /* te->defn should have the form SET client_encoding = 'foo'; */
    char       *defn = pg_strdup(te->defn);
    char       *ptr1;
    char       *ptr2 = NULL;
    int         encoding;
 
    ptr1 = strchr(defn, '\'');
    if (ptr1)
        ptr2 = strchr(++ptr1, '\'');
    if (ptr2)
    {
        *ptr2 = '\0';
        encoding = pg_char_to_encoding(ptr1);
        if (encoding < 0)
            pg_fatal("unrecognized encoding \"%s\"",
                     ptr1);
        AH->public.encoding = encoding;
        setFmtEncoding(encoding);
    }
    else
        pg_fatal("invalid ENCODING item: %s",
                 te->defn);
 
    free(defn);
}
 
static void
processStdStringsEntry(ArchiveHandle *AH, TocEntry *te)
{
    /* te->defn should have the form SET standard_conforming_strings = 'x'; */
    char       *ptr1;
 
    ptr1 = strchr(te->defn, '\'');
    if (ptr1 && strncmp(ptr1, "'on'", 4) == 0)
        AH->public.std_strings = true;
    else if (ptr1 && strncmp(ptr1, "'off'", 5) == 0)
        AH->public.std_strings = false;
    else
        pg_fatal("invalid STDSTRINGS item: %s",
                 te->defn);
}
 
static void
processSearchPathEntry(ArchiveHandle *AH, TocEntry *te)
{
    /*
     * te->defn should contain a command to set search_path.  We just copy it
     * verbatim for use later.
     */
    AH->public.searchpath = pg_strdup(te->defn);
}
 
static void
StrictNamesCheck(RestoreOptions *ropt)
{
    const char *missing_name;
 
    Assert(ropt->strict_names);
 
    if (ropt->schemaNames.head != NULL)
    {
        missing_name = simple_string_list_not_touched(&ropt->schemaNames);
        if (missing_name != NULL)
            pg_fatal("schema \"%s\" not found", missing_name);
    }
 
    if (ropt->tableNames.head != NULL)
    {
        missing_name = simple_string_list_not_touched(&ropt->tableNames);
        if (missing_name != NULL)
            pg_fatal("table \"%s\" not found", missing_name);
    }
 
    if (ropt->indexNames.head != NULL)
    {
        missing_name = simple_string_list_not_touched(&ropt->indexNames);
        if (missing_name != NULL)
            pg_fatal("index \"%s\" not found", missing_name);
    }
 
    if (ropt->functionNames.head != NULL)
    {
        missing_name = simple_string_list_not_touched(&ropt->functionNames);
        if (missing_name != NULL)
            pg_fatal("function \"%s\" not found", missing_name);
    }
 
    if (ropt->triggerNames.head != NULL)
    {
        missing_name = simple_string_list_not_touched(&ropt->triggerNames);
        if (missing_name != NULL)
            pg_fatal("trigger \"%s\" not found", missing_name);
    }
}
 
/*
 * Determine whether we want to restore this TOC entry.
 *
 * Returns 0 if entry should be skipped, or some combination of the
 * REQ_SCHEMA, REQ_DATA, and REQ_STATS bits if we want to restore schema, data
 * and/or statistics portions of this TOC entry, or REQ_SPECIAL if it's a
 * special entry.
 */
static int
_tocEntryRequired(TocEntry *te, teSection curSection, ArchiveHandle *AH)
{
    int         res = REQ_SCHEMA | REQ_DATA;
    RestoreOptions *ropt = AH->public.ropt;
 
    /*
     * For binary upgrade mode, dump pg_largeobject_metadata and the
     * associated pg_shdepend rows. This is faster to restore than the
     * equivalent set of large object commands.  We can only do this for
     * upgrades from v12 and newer; in older versions, pg_largeobject_metadata
     * was created WITH OIDS, so the OID column is hidden and won't be dumped.
     */
    if (ropt->binary_upgrade && AH->public.remoteVersion >= 120000 &&
        strcmp(te->desc, "TABLE DATA") == 0 &&
        (te->catalogId.oid == LargeObjectMetadataRelationId ||
         te->catalogId.oid == SharedDependRelationId))
        return REQ_DATA;
 
    /* These items are treated specially */
    if (strcmp(te->desc, "ENCODING") == 0 ||
        strcmp(te->desc, "STDSTRINGS") == 0 ||
        strcmp(te->desc, "SEARCHPATH") == 0)
        return REQ_SPECIAL;
 
    if (strcmp(te->desc, "STATISTICS DATA") == 0)
    {
        if (!ropt->dumpStatistics)
            return 0;
 
        res = REQ_STATS;
    }
 
    /*
     * DATABASE and DATABASE PROPERTIES also have a special rule: they are
     * restored in createDB mode, and not restored otherwise, independently of
     * all else.
     */
    if (strcmp(te->desc, "DATABASE") == 0 ||
        strcmp(te->desc, "DATABASE PROPERTIES") == 0)
    {
        if (ropt->createDB)
            return REQ_SCHEMA;
        else
            return 0;
    }
 
    /*
     * Process exclusions that affect certain classes of TOC entries.
     */
 
    /* If it's an ACL, maybe ignore it */
    if (ropt->aclsSkip && _tocEntryIsACL(te))
        return 0;
 
    /* If it's a comment, maybe ignore it */
    if (ropt->no_comments && strcmp(te->desc, "COMMENT") == 0)
        return 0;
 
    /* If it's a policy, maybe ignore it */
    if (ropt->no_policies &&
        (strcmp(te->desc, "POLICY") == 0 ||
         strcmp(te->desc, "ROW SECURITY") == 0))
        return 0;
 
    /*
     * If it's a comment on a policy, a publication, or a subscription, maybe
     * ignore it.
     */
    if (strcmp(te->desc, "COMMENT") == 0)
    {
        if (ropt->no_policies &&
            strncmp(te->tag, "POLICY", strlen("POLICY")) == 0)
            return 0;
 
        if (ropt->no_publications &&
            strncmp(te->tag, "PUBLICATION", strlen("PUBLICATION")) == 0)
            return 0;
 
        if (ropt->no_subscriptions &&
            strncmp(te->tag, "SUBSCRIPTION", strlen("SUBSCRIPTION")) == 0)
            return 0;
    }
 
    /*
     * If it's a publication or a table part of a publication, maybe ignore
     * it.
     */
    if (ropt->no_publications &&
        (strcmp(te->desc, "PUBLICATION") == 0 ||
         strcmp(te->desc, "PUBLICATION TABLE") == 0 ||
         strcmp(te->desc, "PUBLICATION TABLES IN SCHEMA") == 0))
        return 0;
 
    /* If it's a security label, maybe ignore it */
    if (ropt->no_security_labels && strcmp(te->desc, "SECURITY LABEL") == 0)
        return 0;
 
    /*
     * If it's a security label on a publication or a subscription, maybe
     * ignore it.
     */
    if (strcmp(te->desc, "SECURITY LABEL") == 0)
    {
        if (ropt->no_publications &&
            strncmp(te->tag, "PUBLICATION", strlen("PUBLICATION")) == 0)
            return 0;
 
        if (ropt->no_subscriptions &&
            strncmp(te->tag, "SUBSCRIPTION", strlen("SUBSCRIPTION")) == 0)
            return 0;
    }
 
    /* If it's a subscription, maybe ignore it */
    if (ropt->no_subscriptions && strcmp(te->desc, "SUBSCRIPTION") == 0)
        return 0;
 
    /* Ignore it if section is not to be dumped/restored */
    switch (curSection)
    {
        case SECTION_PRE_DATA:
            if (!(ropt->dumpSections & DUMP_PRE_DATA))
                return 0;
            break;
        case SECTION_DATA:
            if (!(ropt->dumpSections & DUMP_DATA))
                return 0;
            break;
        case SECTION_POST_DATA:
            if (!(ropt->dumpSections & DUMP_POST_DATA))
                return 0;
            break;
        default:
            /* shouldn't get here, really, but ignore it */
            return 0;
    }
 
    /* Ignore it if rejected by idWanted[] (cf. SortTocFromFile) */
    if (ropt->idWanted && !ropt->idWanted[te->dumpId - 1])
        return 0;
 
    /*
     * Check options for selective dump/restore.
     */
    if (strcmp(te->desc, "ACL") == 0 ||
        strcmp(te->desc, "COMMENT") == 0 ||
        strcmp(te->desc, "STATISTICS DATA") == 0 ||
        strcmp(te->desc, "SECURITY LABEL") == 0)
    {
        /* Database properties react to createDB, not selectivity options. */
        if (strncmp(te->tag, "DATABASE ", 9) == 0)
        {
            if (!ropt->createDB)
                return 0;
        }
        else if (ropt->schemaNames.head != NULL ||
                 ropt->schemaExcludeNames.head != NULL ||
                 ropt->selTypes)
        {
            /*
             * In a selective dump/restore, we want to restore these dependent
             * TOC entry types only if their parent object is being restored.
             * Without selectivity options, we let through everything in the
             * archive.  Note there may be such entries with no parent, eg
             * non-default ACLs for built-in objects.  Also, we make
             * per-column ACLs additionally depend on the table's ACL if any
             * to ensure correct restore order, so those dependencies should
             * be ignored in this check.
             *
             * This code depends on the parent having been marked already,
             * which should be the case; if it isn't, perhaps due to
             * SortTocFromFile rearrangement, skipping the dependent entry
             * seems prudent anyway.
             *
             * Ideally we'd handle, eg, table CHECK constraints this way too.
             * But it's hard to tell which of their dependencies is the one to
             * consult.
             */
            bool        dumpthis = false;
 
            for (int i = 0; i < te->nDeps; i++)
            {
                TocEntry   *pte = getTocEntryByDumpId(AH, te->dependencies[i]);
 
                if (!pte)
                    continue;   /* probably shouldn't happen */
                if (strcmp(pte->desc, "ACL") == 0)
                    continue;   /* ignore dependency on another ACL */
                if (pte->reqs == 0)
                    continue;   /* this object isn't marked, so ignore it */
                /* Found a parent to be dumped, so we want to dump this too */
                dumpthis = true;
                break;
            }
            if (!dumpthis)
                return 0;
        }
    }
    else
    {
        /* Apply selective-restore rules for standalone TOC entries. */
        if (ropt->schemaNames.head != NULL)
        {
            /* If no namespace is specified, it means all. */
            if (!te->namespace)
                return 0;
            if (!simple_string_list_member(&ropt->schemaNames, te->namespace))
                return 0;
        }
 
        if (ropt->schemaExcludeNames.head != NULL &&
            te->namespace &&
            simple_string_list_member(&ropt->schemaExcludeNames, te->namespace))
            return 0;
 
        if (ropt->selTypes)
        {
            if (strcmp(te->desc, "TABLE") == 0 ||
                strcmp(te->desc, "TABLE DATA") == 0 ||
                strcmp(te->desc, "VIEW") == 0 ||
                strcmp(te->desc, "FOREIGN TABLE") == 0 ||
                strcmp(te->desc, "MATERIALIZED VIEW") == 0 ||
                strcmp(te->desc, "MATERIALIZED VIEW DATA") == 0 ||
                strcmp(te->desc, "SEQUENCE") == 0 ||
                strcmp(te->desc, "SEQUENCE SET") == 0)
            {
                if (!ropt->selTable)
                    return 0;
                if (ropt->tableNames.head != NULL &&
                    !simple_string_list_member(&ropt->tableNames, te->tag))
                    return 0;
            }
            else if (strcmp(te->desc, "INDEX") == 0)
            {
                if (!ropt->selIndex)
                    return 0;
                if (ropt->indexNames.head != NULL &&
                    !simple_string_list_member(&ropt->indexNames, te->tag))
                    return 0;
            }
            else if (strcmp(te->desc, "FUNCTION") == 0 ||
                     strcmp(te->desc, "AGGREGATE") == 0 ||
                     strcmp(te->desc, "PROCEDURE") == 0)
            {
                if (!ropt->selFunction)
                    return 0;
                if (ropt->functionNames.head != NULL &&
                    !simple_string_list_member(&ropt->functionNames, te->tag))
                    return 0;
            }
            else if (strcmp(te->desc, "TRIGGER") == 0)
            {
                if (!ropt->selTrigger)
                    return 0;
                if (ropt->triggerNames.head != NULL &&
                    !simple_string_list_member(&ropt->triggerNames, te->tag))
                    return 0;
            }
            else
                return 0;
        }
    }
 
 
    /*
     * Determine whether the TOC entry contains schema and/or data components,
     * and mask off inapplicable REQ bits.  If it had a dataDumper, assume
     * it's both schema and data.  Otherwise it's probably schema-only, but
     * there are exceptions.
     */
    if (!te->hadDumper)
    {
        /*
         * Special Case: If 'SEQUENCE SET' or anything to do with LOs, then it
         * is considered a data entry.  We don't need to check for BLOBS or
         * old-style BLOB COMMENTS entries, because they will have hadDumper =
         * true ... but we do need to check new-style BLOB ACLs, comments,
         * etc.
         */
        if (strcmp(te->desc, "SEQUENCE SET") == 0 ||
            strcmp(te->desc, "BLOB") == 0 ||
            strcmp(te->desc, "BLOB METADATA") == 0 ||
            (strcmp(te->desc, "ACL") == 0 &&
             strncmp(te->tag, "LARGE OBJECT", 12) == 0) ||
            (strcmp(te->desc, "COMMENT") == 0 &&
             strncmp(te->tag, "LARGE OBJECT", 12) == 0) ||
            (strcmp(te->desc, "SECURITY LABEL") == 0 &&
             strncmp(te->tag, "LARGE OBJECT", 12) == 0))
            res = res & REQ_DATA;
        else
            res = res & ~REQ_DATA;
    }
 
    /*
     * If there's no definition command, there's no schema component.  Treat
     * "load via partition root" comments as not schema.
     */
    if (!te->defn || !te->defn[0] ||
        strncmp(te->defn, "-- load via partition root ", 27) == 0)
        res = res & ~REQ_SCHEMA;
 
    /*
     * Special case: <Init> type with <Max OID> tag; this is obsolete and we
     * always ignore it.
     */
    if ((strcmp(te->desc, "<Init>") == 0) && (strcmp(te->tag, "Max OID") == 0))
        return 0;
 
    /* Mask it if we don't want data */
    if (!ropt->dumpData)
    {
        /*
         * The sequence_data option overrides dumpData for SEQUENCE SET.
         *
         * In binary-upgrade mode, even with dumpData unset, we do not mask
         * out large objects.  (Only large object definitions, comments and
         * other metadata should be generated in binary-upgrade mode, not the
         * actual data, but that need not concern us here.)
         */
        if (!(ropt->sequence_data && strcmp(te->desc, "SEQUENCE SET") == 0) &&
            !(ropt->binary_upgrade &&
              (strcmp(te->desc, "BLOB") == 0 ||
               strcmp(te->desc, "BLOB METADATA") == 0 ||
               (strcmp(te->desc, "ACL") == 0 &&
                strncmp(te->tag, "LARGE OBJECT", 12) == 0) ||
               (strcmp(te->desc, "COMMENT") == 0 &&
                strncmp(te->tag, "LARGE OBJECT", 12) == 0) ||
               (strcmp(te->desc, "SECURITY LABEL") == 0 &&
                strncmp(te->tag, "LARGE OBJECT", 12) == 0))))
            res = res & (REQ_SCHEMA | REQ_STATS);
    }
 
    /* Mask it if we don't want schema */
    if (!ropt->dumpSchema)
        res = res & (REQ_DATA | REQ_STATS);
 
    return res;
}
 
/*
 * Identify which pass we should restore this TOC entry in.
 *
 * See notes with the RestorePass typedef in pg_backup_archiver.h.
 */
static RestorePass
_tocEntryRestorePass(TocEntry *te)
{
    /* "ACL LANGUAGE" was a crock emitted only in PG 7.4 */
    if (strcmp(te->desc, "ACL") == 0 ||
        strcmp(te->desc, "ACL LANGUAGE") == 0 ||
        strcmp(te->desc, "DEFAULT ACL") == 0)
        return RESTORE_PASS_ACL;
    if (strcmp(te->desc, "EVENT TRIGGER") == 0 ||
        strcmp(te->desc, "MATERIALIZED VIEW DATA") == 0)
        return RESTORE_PASS_POST_ACL;
 
    /*
     * Comments and security labels need to be emitted in the same pass as
     * their parent objects. ACLs haven't got comments and security labels,
     * and neither do matview data objects, but event triggers do.
     * (Fortunately, event triggers haven't got ACLs, or we'd need yet another
     * weird special case.)
     */
    if ((strcmp(te->desc, "COMMENT") == 0 ||
         strcmp(te->desc, "SECURITY LABEL") == 0) &&
        strncmp(te->tag, "EVENT TRIGGER ", 14) == 0)
        return RESTORE_PASS_POST_ACL;
 
    /*
     * If statistics data is dependent on materialized view data, it must be
     * deferred to RESTORE_PASS_POST_ACL.  Those entries are already marked as
     * SECTION_POST_DATA, and some other stats entries (e.g., index stats)
     * will also be marked as SECTION_POST_DATA.  Additionally, our lookahead
     * code in fetchAttributeStats() assumes that we dump all statistics data
     * entries in TOC order.  To ensure this assumption holds, we move all
     * statistics data entries in SECTION_POST_DATA to RESTORE_PASS_POST_ACL.
     */
    if (strcmp(te->desc, "STATISTICS DATA") == 0 &&
        te->section == SECTION_POST_DATA)
        return RESTORE_PASS_POST_ACL;
 
    /* All else can be handled in the main pass. */
    return RESTORE_PASS_MAIN;
}
 
/*
 * Identify TOC entries that are ACLs.
 *
 * Note: it seems worth duplicating some code here to avoid a hard-wired
 * assumption that these are exactly the same entries that we restore during
 * the RESTORE_PASS_ACL phase.
 */
static bool
_tocEntryIsACL(TocEntry *te)
{
    /* "ACL LANGUAGE" was a crock emitted only in PG 7.4 */
    if (strcmp(te->desc, "ACL") == 0 ||
        strcmp(te->desc, "ACL LANGUAGE") == 0 ||
        strcmp(te->desc, "DEFAULT ACL") == 0)
        return true;
    return false;
}
 
/*
 * Issue SET commands for parameters that we want to have set the same way
 * at all times during execution of a restore script.
 */
static void
_doSetFixedOutputState(ArchiveHandle *AH)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    /*
     * Disable timeouts to allow for slow commands, idle parallel workers, etc
     */
    ahprintf(AH, "SET statement_timeout = 0;\n");
    ahprintf(AH, "SET lock_timeout = 0;\n");
    ahprintf(AH, "SET idle_in_transaction_session_timeout = 0;\n");
    ahprintf(AH, "SET transaction_timeout = 0;\n");
 
    /* Select the correct character set encoding */
    ahprintf(AH, "SET client_encoding = '%s';\n",
             pg_encoding_to_char(AH->public.encoding));
 
    /* Select the correct string literal syntax */
    ahprintf(AH, "SET standard_conforming_strings = %s;\n",
             AH->public.std_strings ? "on" : "off");
 
    /* Select the role to be used during restore */
    if (ropt && ropt->use_role)
        ahprintf(AH, "SET ROLE %s;\n", fmtId(ropt->use_role));
 
    /* Select the dump-time search_path */
    if (AH->public.searchpath)
        ahprintf(AH, "%s", AH->public.searchpath);
 
    /* Make sure function checking is disabled */
    ahprintf(AH, "SET check_function_bodies = false;\n");
 
    /* Ensure that all valid XML data will be accepted */
    ahprintf(AH, "SET xmloption = content;\n");
 
    /* Avoid annoying notices etc */
    ahprintf(AH, "SET client_min_messages = warning;\n");
 
    /* Adjust row-security state */
    if (ropt && ropt->enable_row_security)
        ahprintf(AH, "SET row_security = on;\n");
    else
        ahprintf(AH, "SET row_security = off;\n");
 
    /*
     * In --transaction-size mode, we should always be in a transaction when
     * we begin to restore objects.
     */
    if (ropt && ropt->txn_size > 0)
    {
        if (AH->connection)
            StartTransaction(&AH->public);
        else
            ahprintf(AH, "\nBEGIN;\n");
        AH->txnCount = 0;
    }
 
    ahprintf(AH, "\n");
}
 
/*
 * Issue a SET SESSION AUTHORIZATION command.  Caller is responsible
 * for updating state if appropriate.  If user is NULL or an empty string,
 * the specification DEFAULT will be used.
 */
static void
_doSetSessionAuth(ArchiveHandle *AH, const char *user)
{
    PQExpBuffer cmd = createPQExpBuffer();
 
    appendPQExpBufferStr(cmd, "SET SESSION AUTHORIZATION ");
 
    /*
     * SQL requires a string literal here.  Might as well be correct.
     */
    if (user && *user)
        appendStringLiteralAHX(cmd, user, AH);
    else
        appendPQExpBufferStr(cmd, "DEFAULT");
    appendPQExpBufferChar(cmd, ';');
 
    if (RestoringToDB(AH))
    {
        PGresult   *res;
 
        res = PQexec(AH->connection, cmd->data);
 
        if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
            /* NOT warn_or_exit_horribly... use -O instead to skip this. */
            pg_fatal("could not set session user to \"%s\": %s",
                     user, PQerrorMessage(AH->connection));
 
        PQclear(res);
    }
    else
        ahprintf(AH, "%s\n\n", cmd->data);
 
    destroyPQExpBuffer(cmd);
}
 
 
/*
 * Issue the commands to connect to the specified database.
 *
 * If we're currently restoring right into a database, this will
 * actually establish a connection. Otherwise it puts a \connect into
 * the script output.
 */
static void
_reconnectToDB(ArchiveHandle *AH, const char *dbname)
{
    if (RestoringToDB(AH))
        ReconnectToServer(AH, dbname);
    else
    {
        PQExpBufferData connectbuf;
        RestoreOptions *ropt = AH->public.ropt;
 
        /*
         * We must temporarily exit restricted mode for \connect, etc.
         * Anything added between this line and the following \restrict must
         * be careful to avoid any possible meta-command injection vectors.
         */
        ahprintf(AH, "\\unrestrict %s\n", ropt->restrict_key);
 
        initPQExpBuffer(&connectbuf);
        appendPsqlMetaConnect(&connectbuf, dbname);
        ahprintf(AH, "%s", connectbuf.data);
        termPQExpBuffer(&connectbuf);
 
        ahprintf(AH, "\\restrict %s\n\n", ropt->restrict_key);
    }
 
    /*
     * NOTE: currUser keeps track of what the imaginary session user in our
     * script is.  It's now effectively reset to the original userID.
     */
    free(AH->currUser);
    AH->currUser = NULL;
 
    /* don't assume we still know the output schema, tablespace, etc either */
    free(AH->currSchema);
    AH->currSchema = NULL;
 
    free(AH->currTableAm);
    AH->currTableAm = NULL;
 
    free(AH->currTablespace);
    AH->currTablespace = NULL;
 
    /* re-establish fixed state */
    _doSetFixedOutputState(AH);
}
 
/*
 * Become the specified user, and update state to avoid redundant commands
 *
 * NULL or empty argument is taken to mean restoring the session default
 */
static void
_becomeUser(ArchiveHandle *AH, const char *user)
{
    if (!user)
        user = "";              /* avoid null pointers */
 
    if (AH->currUser && strcmp(AH->currUser, user) == 0)
        return;                 /* no need to do anything */
 
    _doSetSessionAuth(AH, user);
 
    /*
     * NOTE: currUser keeps track of what the imaginary session user in our
     * script is
     */
    free(AH->currUser);
    AH->currUser = pg_strdup(user);
}
 
/*
 * Become the owner of the given TOC entry object.  If
 * changes in ownership are not allowed, this doesn't do anything.
 */
static void
_becomeOwner(ArchiveHandle *AH, TocEntry *te)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    if (ropt && (ropt->noOwner || !ropt->use_setsessauth))
        return;
 
    _becomeUser(AH, te->owner);
}
 
 
/*
 * Issue the commands to select the specified schema as the current schema
 * in the target database.
 */
static void
_selectOutputSchema(ArchiveHandle *AH, const char *schemaName)
{
    PQExpBuffer qry;
 
    /*
     * If there was a SEARCHPATH TOC entry, we're supposed to just stay with
     * that search_path rather than switching to entry-specific paths.
     * Otherwise, it's an old archive that will not restore correctly unless
     * we set the search_path as it's expecting.
     */
    if (AH->public.searchpath)
        return;
 
    if (!schemaName || *schemaName == '\0' ||
        (AH->currSchema && strcmp(AH->currSchema, schemaName) == 0))
        return;                 /* no need to do anything */
 
    qry = createPQExpBuffer();
 
    appendPQExpBuffer(qry, "SET search_path = %s",
                      fmtId(schemaName));
    if (strcmp(schemaName, "pg_catalog") != 0)
        appendPQExpBufferStr(qry, ", pg_catalog");
 
    if (RestoringToDB(AH))
    {
        PGresult   *res;
 
        res = PQexec(AH->connection, qry->data);
 
        if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
            warn_or_exit_horribly(AH,
                                  "could not set \"search_path\" to \"%s\": %s",
                                  schemaName, PQerrorMessage(AH->connection));
 
        PQclear(res);
    }
    else
        ahprintf(AH, "%s;\n\n", qry->data);
 
    free(AH->currSchema);
    AH->currSchema = pg_strdup(schemaName);
 
    destroyPQExpBuffer(qry);
}
 
/*
 * Issue the commands to select the specified tablespace as the current one
 * in the target database.
 */
static void
_selectTablespace(ArchiveHandle *AH, const char *tablespace)
{
    RestoreOptions *ropt = AH->public.ropt;
    PQExpBuffer qry;
    const char *want,
               *have;
 
    /* do nothing in --no-tablespaces mode */
    if (ropt->noTablespace)
        return;
 
    have = AH->currTablespace;
    want = tablespace;
 
    /* no need to do anything for non-tablespace object */
    if (!want)
        return;
 
    if (have && strcmp(want, have) == 0)
        return;                 /* no need to do anything */
 
    qry = createPQExpBuffer();
 
    if (strcmp(want, "") == 0)
    {
        /* We want the tablespace to be the database's default */
        appendPQExpBufferStr(qry, "SET default_tablespace = ''");
    }
    else
    {
        /* We want an explicit tablespace */
        appendPQExpBuffer(qry, "SET default_tablespace = %s", fmtId(want));
    }
 
    if (RestoringToDB(AH))
    {
        PGresult   *res;
 
        res = PQexec(AH->connection, qry->data);
 
        if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
            warn_or_exit_horribly(AH,
                                  "could not set \"default_tablespace\" to %s: %s",
                                  fmtId(want), PQerrorMessage(AH->connection));
 
        PQclear(res);
    }
    else
        ahprintf(AH, "%s;\n\n", qry->data);
 
    free(AH->currTablespace);
    AH->currTablespace = pg_strdup(want);
 
    destroyPQExpBuffer(qry);
}
 
/*
 * Set the proper default_table_access_method value for the table.
 */
static void
_selectTableAccessMethod(ArchiveHandle *AH, const char *tableam)
{
    RestoreOptions *ropt = AH->public.ropt;
    PQExpBuffer cmd;
    const char *want,
               *have;
 
    /* do nothing in --no-table-access-method mode */
    if (ropt->noTableAm)
        return;
 
    have = AH->currTableAm;
    want = tableam;
 
    if (!want)
        return;
 
    if (have && strcmp(want, have) == 0)
        return;
 
    cmd = createPQExpBuffer();
    appendPQExpBuffer(cmd, "SET default_table_access_method = %s;", fmtId(want));
 
    if (RestoringToDB(AH))
    {
        PGresult   *res;
 
        res = PQexec(AH->connection, cmd->data);
 
        if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
            warn_or_exit_horribly(AH,
                                  "could not set \"default_table_access_method\": %s",
                                  PQerrorMessage(AH->connection));
 
        PQclear(res);
    }
    else
        ahprintf(AH, "%s\n\n", cmd->data);
 
    destroyPQExpBuffer(cmd);
 
    free(AH->currTableAm);
    AH->currTableAm = pg_strdup(want);
}
 
/*
 * Set the proper default table access method for a table without storage.
 * Currently, this is required only for partitioned tables with a table AM.
 */
static void
_printTableAccessMethodNoStorage(ArchiveHandle *AH, TocEntry *te)
{
    RestoreOptions *ropt = AH->public.ropt;
    const char *tableam = te->tableam;
    PQExpBuffer cmd;
 
    /* do nothing in --no-table-access-method mode */
    if (ropt->noTableAm)
        return;
 
    if (!tableam)
        return;
 
    Assert(te->relkind == RELKIND_PARTITIONED_TABLE);
 
    cmd = createPQExpBuffer();
 
    appendPQExpBufferStr(cmd, "ALTER TABLE ");
    appendPQExpBuffer(cmd, "%s ", fmtQualifiedId(te->namespace, te->tag));
    appendPQExpBuffer(cmd, "SET ACCESS METHOD %s;",
                      fmtId(tableam));
 
    if (RestoringToDB(AH))
    {
        PGresult   *res;
 
        res = PQexec(AH->connection, cmd->data);
 
        if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
            warn_or_exit_horribly(AH,
                                  "could not alter table access method: %s",
                                  PQerrorMessage(AH->connection));
        PQclear(res);
    }
    else
        ahprintf(AH, "%s\n\n", cmd->data);
 
    destroyPQExpBuffer(cmd);
}
 
/*
 * Extract an object description for a TOC entry, and append it to buf.
 *
 * This is used for ALTER ... OWNER TO.
 *
 * If the object type has no owner, do nothing.
 */
static void
_getObjectDescription(PQExpBuffer buf, const TocEntry *te)
{
    const char *type = te->desc;
 
    /* objects that don't require special decoration */
    if (strcmp(type, "COLLATION") == 0 ||
        strcmp(type, "CONVERSION") == 0 ||
        strcmp(type, "DOMAIN") == 0 ||
        strcmp(type, "FOREIGN TABLE") == 0 ||
        strcmp(type, "MATERIALIZED VIEW") == 0 ||
        strcmp(type, "SEQUENCE") == 0 ||
        strcmp(type, "STATISTICS") == 0 ||
        strcmp(type, "TABLE") == 0 ||
        strcmp(type, "TEXT SEARCH DICTIONARY") == 0 ||
        strcmp(type, "TEXT SEARCH CONFIGURATION") == 0 ||
        strcmp(type, "TYPE") == 0 ||
        strcmp(type, "VIEW") == 0 ||
    /* non-schema-specified objects */
        strcmp(type, "DATABASE") == 0 ||
        strcmp(type, "PROCEDURAL LANGUAGE") == 0 ||
        strcmp(type, "SCHEMA") == 0 ||
        strcmp(type, "EVENT TRIGGER") == 0 ||
        strcmp(type, "FOREIGN DATA WRAPPER") == 0 ||
        strcmp(type, "SERVER") == 0 ||
        strcmp(type, "PUBLICATION") == 0 ||
        strcmp(type, "SUBSCRIPTION") == 0)
    {
        appendPQExpBuffer(buf, "%s ", type);
        if (te->namespace && *te->namespace)
            appendPQExpBuffer(buf, "%s.", fmtId(te->namespace));
        appendPQExpBufferStr(buf, fmtId(te->tag));
    }
    /* LOs just have a name, but it's numeric so must not use fmtId */
    else if (strcmp(type, "BLOB") == 0)
    {
        appendPQExpBuffer(buf, "LARGE OBJECT %s", te->tag);
    }
 
    /*
     * These object types require additional decoration.  Fortunately, the
     * information needed is exactly what's in the DROP command.
     */
    else if (strcmp(type, "AGGREGATE") == 0 ||
             strcmp(type, "FUNCTION") == 0 ||
             strcmp(type, "OPERATOR") == 0 ||
             strcmp(type, "OPERATOR CLASS") == 0 ||
             strcmp(type, "OPERATOR FAMILY") == 0 ||
             strcmp(type, "PROCEDURE") == 0)
    {
        /* Chop "DROP " off the front and make a modifiable copy */
        char       *first = pg_strdup(te->dropStmt + 5);
        char       *last;
 
        /* point to last character in string */
        last = first + strlen(first) - 1;
 
        /* Strip off any ';' or '\n' at the end */
        while (last >= first && (*last == '\n' || *last == ';'))
            last--;
        *(last + 1) = '\0';
 
        appendPQExpBufferStr(buf, first);
 
        free(first);
        return;
    }
    /* these object types don't have separate owners */
    else if (strcmp(type, "CAST") == 0 ||
             strcmp(type, "CHECK CONSTRAINT") == 0 ||
             strcmp(type, "CONSTRAINT") == 0 ||
             strcmp(type, "DATABASE PROPERTIES") == 0 ||
             strcmp(type, "DEFAULT") == 0 ||
             strcmp(type, "FK CONSTRAINT") == 0 ||
             strcmp(type, "INDEX") == 0 ||
             strcmp(type, "RULE") == 0 ||
             strcmp(type, "TRIGGER") == 0 ||
             strcmp(type, "ROW SECURITY") == 0 ||
             strcmp(type, "POLICY") == 0 ||
             strcmp(type, "USER MAPPING") == 0)
    {
        /* do nothing */
    }
    else
        pg_fatal("don't know how to set owner for object type \"%s\"", type);
}
 
/*
 * Emit the SQL commands to create the object represented by a TOC entry
 *
 * This now also includes issuing an ALTER OWNER command to restore the
 * object's ownership, if wanted.  But note that the object's permissions
 * will remain at default, until the matching ACL TOC entry is restored.
 */
static void
_printTocEntry(ArchiveHandle *AH, TocEntry *te, const char *pfx)
{
    RestoreOptions *ropt = AH->public.ropt;
 
    /*
     * Select owner, schema, tablespace and default AM as necessary. The
     * default access method for partitioned tables is handled after
     * generating the object definition, as it requires an ALTER command
     * rather than SET.
     */
    _becomeOwner(AH, te);
    _selectOutputSchema(AH, te->namespace);
    _selectTablespace(AH, te->tablespace);
    if (te->relkind != RELKIND_PARTITIONED_TABLE)
        _selectTableAccessMethod(AH, te->tableam);
 
    /* Emit header comment for item */
    if (!AH->noTocComments)
    {
        char       *sanitized_name;
        char       *sanitized_schema;
        char       *sanitized_owner;
 
        ahprintf(AH, "--\n");
        if (AH->public.verbose)
        {
            ahprintf(AH, "-- TOC entry %d (class %u OID %u)\n",
                     te->dumpId, te->catalogId.tableoid, te->catalogId.oid);
            if (te->nDeps > 0)
            {
                int         i;
 
                ahprintf(AH, "-- Dependencies:");
                for (i = 0; i < te->nDeps; i++)
                    ahprintf(AH, " %d", te->dependencies[i]);
                ahprintf(AH, "\n");
            }
        }
 
        sanitized_name = sanitize_line(te->tag, false);
        sanitized_schema = sanitize_line(te->namespace, true);
        sanitized_owner = sanitize_line(ropt->noOwner ? NULL : te->owner, true);
 
        ahprintf(AH, "-- %sName: %s; Type: %s; Schema: %s; Owner: %s",
                 pfx, sanitized_name, te->desc, sanitized_schema,
                 sanitized_owner);
 
        free(sanitized_name);
        free(sanitized_schema);
        free(sanitized_owner);
 
        if (te->tablespace && strlen(te->tablespace) > 0 && !ropt->noTablespace)
        {
            char       *sanitized_tablespace;
 
            sanitized_tablespace = sanitize_line(te->tablespace, false);
            ahprintf(AH, "; Tablespace: %s", sanitized_tablespace);
            free(sanitized_tablespace);
        }
        ahprintf(AH, "\n");
 
        if (AH->PrintExtraTocPtr != NULL)
            AH->PrintExtraTocPtr(AH, te);
        ahprintf(AH, "--\n\n");
    }
 
    /*
     * Actually print the definition.  Normally we can just print the defn
     * string if any, but we have four special cases:
     *
     * 1. A crude hack for suppressing AUTHORIZATION clause that old pg_dump
     * versions put into CREATE SCHEMA.  Don't mutate the variant for schema
     * "public" that is a comment.  We have to do this when --no-owner mode is
     * selected.  This is ugly, but I see no other good way ...
     *
     * 2. BLOB METADATA entries need special processing since their defn
     * strings are just lists of OIDs, not complete SQL commands.
     *
     * 3. ACL LARGE OBJECTS entries need special processing because they
     * contain only one copy of the ACL GRANT/REVOKE commands, which we must
     * apply to each large object listed in the associated BLOB METADATA.
     *
     * 4. Entries with a defnDumper need to call it to generate the
     * definition.  This is primarily intended to provide a way to save memory
     * for objects that would otherwise need a lot of it (e.g., statistics
     * data).
     */
    if (ropt->noOwner &&
        strcmp(te->desc, "SCHEMA") == 0 && strncmp(te->defn, "--", 2) != 0)
    {
        ahprintf(AH, "CREATE SCHEMA %s;\n\n\n", fmtId(te->tag));
    }
    else if (strcmp(te->desc, "BLOB METADATA") == 0)
    {
        IssueCommandPerBlob(AH, te, "SELECT pg_catalog.lo_create('", "')");
    }
    else if (strcmp(te->desc, "ACL") == 0 &&
             strncmp(te->tag, "LARGE OBJECTS", 13) == 0)
    {
        IssueACLPerBlob(AH, te);
    }
    else if (te->defnLen && AH->format != archTar)
    {
        /*
         * If defnLen is set, the defnDumper has already been called for this
         * TOC entry.  We don't normally expect a defnDumper to be called for
         * a TOC entry a second time in _printTocEntry(), but there's an
         * exception.  The tar format first calls WriteToc(), which scans the
         * entire TOC, and then it later calls RestoreArchive() to generate
         * restore.sql, which scans the TOC again.  There doesn't appear to be
         * a good way to prevent a second defnDumper call in this case without
         * storing the definition in memory, which defeats the purpose.  This
         * second defnDumper invocation should generate the same output as the
         * first, but even if it doesn't, the worst-case scenario is that
         * restore.sql might have different statistics data than the archive.
         *
         * In all other cases, encountering a TOC entry a second time in
         * _printTocEntry() is unexpected, so we fail because one of our
         * assumptions must no longer hold true.
         *
         * XXX This is a layering violation, but the alternative is an awkward
         * and complicated callback infrastructure for this special case. This
         * might be worth revisiting in the future.
         */
        pg_fatal("unexpected TOC entry in _printTocEntry(): %d %s %s",
                 te->dumpId, te->desc, te->tag);
    }
    else if (te->defnDumper)
    {
        char       *defn = te->defnDumper((Archive *) AH, te->defnDumperArg, te);
 
        te->defnLen = ahprintf(AH, "%s\n\n", defn);
        pg_free(defn);
    }
    else if (te->defn && strlen(te->defn) > 0)
    {
        ahprintf(AH, "%s\n\n", te->defn);
 
        /*
         * If the defn string contains multiple SQL commands, txn_size mode
         * should count it as N actions not one.  But rather than build a full
         * SQL parser, approximate this by counting semicolons.  One case
         * where that tends to be badly fooled is function definitions, so
         * ignore them.  (restore_toc_entry will count one action anyway.)
         */
        if (ropt->txn_size > 0 &&
            strcmp(te->desc, "FUNCTION") != 0 &&
            strcmp(te->desc, "PROCEDURE") != 0)
        {
            const char *p = te->defn;
            int         nsemis = 0;
 
            while ((p = strchr(p, ';')) != NULL)
            {
                nsemis++;
                p++;
            }
            if (nsemis > 1)
                AH->txnCount += nsemis - 1;
        }
    }
 
    /*
     * If we aren't using SET SESSION AUTH to determine ownership, we must
     * instead issue an ALTER OWNER command.  Schema "public" is special; when
     * a dump emits a comment in lieu of creating it, we use ALTER OWNER even
     * when using SET SESSION for all other objects.  We assume that anything
     * without a DROP command is not a separately ownable object.
     */
    if (!ropt->noOwner &&
        (!ropt->use_setsessauth ||
         (strcmp(te->desc, "SCHEMA") == 0 &&
          strncmp(te->defn, "--", 2) == 0)) &&
        te->owner && strlen(te->owner) > 0 &&
        te->dropStmt && strlen(te->dropStmt) > 0)
    {
        if (strcmp(te->desc, "BLOB METADATA") == 0)
        {
            /* BLOB METADATA needs special code to handle multiple LOs */
            char       *cmdEnd = psprintf(" OWNER TO %s", fmtId(te->owner));
 
            IssueCommandPerBlob(AH, te, "ALTER LARGE OBJECT ", cmdEnd);
            pg_free(cmdEnd);
        }
        else
        {
            /* For all other cases, we can use _getObjectDescription */
            PQExpBufferData temp;
 
            initPQExpBuffer(&temp);
            _getObjectDescription(&temp, te);
 
            /*
             * If _getObjectDescription() didn't fill the buffer, then there
             * is no owner.
             */
            if (temp.data[0])
                ahprintf(AH, "ALTER %s OWNER TO %s;\n\n",
                         temp.data, fmtId(te->owner));
            termPQExpBuffer(&temp);
        }
    }
 
    /*
     * Select a partitioned table's default AM, once the table definition has
     * been generated.
     */
    if (te->relkind == RELKIND_PARTITIONED_TABLE)
        _printTableAccessMethodNoStorage(AH, te);
 
    /*
     * If it's an ACL entry, it might contain SET SESSION AUTHORIZATION
     * commands, so we can no longer assume we know the current auth setting.
     */
    if (_tocEntryIsACL(te))
    {
        free(AH->currUser);
        AH->currUser = NULL;
    }
}
 
/*
 * Write the file header for a custom-format archive
 */
void
WriteHead(ArchiveHandle *AH)
{
    struct tm   crtm;
 
    AH->WriteBufPtr(AH, "PGDMP", 5);    /* Magic code */
    AH->WriteBytePtr(AH, ARCHIVE_MAJOR(AH->version));
    AH->WriteBytePtr(AH, ARCHIVE_MINOR(AH->version));
    AH->WriteBytePtr(AH, ARCHIVE_REV(AH->version));
    AH->WriteBytePtr(AH, AH->intSize);
    AH->WriteBytePtr(AH, AH->offSize);
    AH->WriteBytePtr(AH, AH->format);
    AH->WriteBytePtr(AH, AH->compression_spec.algorithm);
    crtm = *localtime(&AH->createDate);
    WriteInt(AH, crtm.tm_sec);
    WriteInt(AH, crtm.tm_min);
    WriteInt(AH, crtm.tm_hour);
    WriteInt(AH, crtm.tm_mday);
    WriteInt(AH, crtm.tm_mon);
    WriteInt(AH, crtm.tm_year);
    WriteInt(AH, crtm.tm_isdst);
    WriteStr(AH, PQdb(AH->connection));
    WriteStr(AH, AH->public.remoteVersionStr);
    WriteStr(AH, PG_VERSION);
}
 
void
ReadHead(ArchiveHandle *AH)
{
    char       *errmsg;
    char        vmaj,
                vmin,
                vrev;
    int         fmt;
 
    /*
     * If we haven't already read the header, do so.
     *
     * NB: this code must agree with _discoverArchiveFormat().  Maybe find a
     * way to unify the cases?
     */
    if (!AH->readHeader)
    {
        char        tmpMag[7];
 
        AH->ReadBufPtr(AH, tmpMag, 5);
 
        if (strncmp(tmpMag, "PGDMP", 5) != 0)
            pg_fatal("did not find magic string in file header");
    }
 
    vmaj = AH->ReadBytePtr(AH);
    vmin = AH->ReadBytePtr(AH);
 
    if (vmaj > 1 || (vmaj == 1 && vmin > 0))    /* Version > 1.0 */
        vrev = AH->ReadBytePtr(AH);
    else
        vrev = 0;
 
    AH->version = MAKE_ARCHIVE_VERSION(vmaj, vmin, vrev);
 
    if (AH->version < K_VERS_1_0 || AH->version > K_VERS_MAX)
        pg_fatal("unsupported version (%d.%d) in file header",
                 vmaj, vmin);
 
    AH->intSize = AH->ReadBytePtr(AH);
    if (AH->intSize > 32)
        pg_fatal("sanity check on integer size (%zu) failed", AH->intSize);
 
    if (AH->intSize > sizeof(int))
        pg_log_warning("archive was made on a machine with larger integers, some operations might fail");
 
    if (AH->version >= K_VERS_1_7)
        AH->offSize = AH->ReadBytePtr(AH);
    else
        AH->offSize = AH->intSize;
 
    fmt = AH->ReadBytePtr(AH);
 
    if (AH->format != fmt)
        pg_fatal("expected format (%d) differs from format found in file (%d)",
                 AH->format, fmt);
 
    if (AH->version >= K_VERS_1_15)
        AH->compression_spec.algorithm = AH->ReadBytePtr(AH);
    else if (AH->version >= K_VERS_1_2)
    {
        /* Guess the compression method based on the level */
        if (AH->version < K_VERS_1_4)
            AH->compression_spec.level = AH->ReadBytePtr(AH);
        else
            AH->compression_spec.level = ReadInt(AH);
 
        if (AH->compression_spec.level != 0)
            AH->compression_spec.algorithm = PG_COMPRESSION_GZIP;
    }
    else
        AH->compression_spec.algorithm = PG_COMPRESSION_GZIP;
 
    errmsg = supports_compression(AH->compression_spec);
    if (errmsg)
    {
        pg_log_warning("archive is compressed, but this installation does not support compression (%s) -- no data will be available",
                       errmsg);
        pg_free(errmsg);
    }
 
    if (AH->version >= K_VERS_1_4)
    {
        struct tm   crtm;
 
        crtm.tm_sec = ReadInt(AH);
        crtm.tm_min = ReadInt(AH);
        crtm.tm_hour = ReadInt(AH);
        crtm.tm_mday = ReadInt(AH);
        crtm.tm_mon = ReadInt(AH);
        crtm.tm_year = ReadInt(AH);
        crtm.tm_isdst = ReadInt(AH);
 
        /*
         * Newer versions of glibc have mktime() report failure if tm_isdst is
         * inconsistent with the prevailing timezone, e.g. tm_isdst = 1 when
         * TZ=UTC.  This is problematic when restoring an archive under a
         * different timezone setting.  If we get a failure, try again with
         * tm_isdst set to -1 ("don't know").
         *
         * XXX with or without this hack, we reconstruct createDate
         * incorrectly when the prevailing timezone is different from
         * pg_dump's.  Next time we bump the archive version, we should flush
         * this representation and store a plain seconds-since-the-Epoch
         * timestamp instead.
         */
        AH->createDate = mktime(&crtm);
        if (AH->createDate == (time_t) -1)
        {
            crtm.tm_isdst = -1;
            AH->createDate = mktime(&crtm);
            if (AH->createDate == (time_t) -1)
                pg_log_warning("invalid creation date in header");
        }
    }
 
    if (AH->version >= K_VERS_1_4)
    {
        AH->archdbname = ReadStr(AH);
    }
 
    if (AH->version >= K_VERS_1_10)
    {
        AH->archiveRemoteVersion = ReadStr(AH);
        AH->archiveDumpVersion = ReadStr(AH);
    }
}
 
 
/*
 * checkSeek
 *    check to see if ftell/fseek can be performed.
 */
bool
checkSeek(FILE *fp)
{
    pgoff_t     tpos;
 
    /* Check that ftello works on this file */
    tpos = ftello(fp);
    if (tpos < 0)
        return false;
 
    /*
     * Check that fseeko(SEEK_SET) works, too.  NB: we used to try to test
     * this with fseeko(fp, 0, SEEK_CUR).  But some platforms treat that as a
     * successful no-op even on files that are otherwise unseekable.
     */
    if (fseeko(fp, tpos, SEEK_SET) != 0)
        return false;
 
    return true;
}
 
 
/*
 * dumpTimestamp
 */
static void
dumpTimestamp(ArchiveHandle *AH, const char *msg, time_t tim)
{
    char        buf[64];
 
    if (strftime(buf, sizeof(buf), PGDUMP_STRFTIME_FMT, localtime(&tim)) != 0)
        ahprintf(AH, "-- %s %s\n\n", msg, buf);
}
 
/*
 * Main engine for parallel restore.
 *
 * Parallel restore is done in three phases.  In this first phase,
 * we'll process all SECTION_PRE_DATA TOC entries that are allowed to be
 * processed in the RESTORE_PASS_MAIN pass.  (In practice, that's all
 * PRE_DATA items other than ACLs.)  Entries we can't process now are
 * added to the pending_list for later phases to deal with.
 */
static void
restore_toc_entries_prefork(ArchiveHandle *AH, TocEntry *pending_list)
{
    bool        skipped_some;
    TocEntry   *next_work_item;
 
    pg_log_debug("entering restore_toc_entries_prefork");
 
    /* Adjust dependency information */
    fix_dependencies(AH);
 
    /*
     * Do all the early stuff in a single connection in the parent. There's no
     * great point in running it in parallel, in fact it will actually run
     * faster in a single connection because we avoid all the connection and
     * setup overhead.  Also, pre-9.2 pg_dump versions were not very good
     * about showing all the dependencies of SECTION_PRE_DATA items, so we do
     * not risk trying to process them out-of-order.
     *
     * Stuff that we can't do immediately gets added to the pending_list.
     * Note: we don't yet filter out entries that aren't going to be restored.
     * They might participate in dependency chains connecting entries that
     * should be restored, so we treat them as live until we actually process
     * them.
     *
     * Note: as of 9.2, it should be guaranteed that all PRE_DATA items appear
     * before DATA items, and all DATA items before POST_DATA items.  That is
     * not certain to be true in older archives, though, and in any case use
     * of a list file would destroy that ordering (cf. SortTocFromFile).  So
     * this loop cannot assume that it holds.
     */
    AH->restorePass = RESTORE_PASS_MAIN;
    skipped_some = false;
    for (next_work_item = AH->toc->next; next_work_item != AH->toc; next_work_item = next_work_item->next)
    {
        bool        do_now = true;
 
        if (next_work_item->section != SECTION_PRE_DATA)
        {
            /* DATA and POST_DATA items are just ignored for now */
            if (next_work_item->section == SECTION_DATA ||
                next_work_item->section == SECTION_POST_DATA)
            {
                do_now = false;
                skipped_some = true;
            }
            else
            {
                /*
                 * SECTION_NONE items, such as comments, can be processed now
                 * if we are still in the PRE_DATA part of the archive.  Once
                 * we've skipped any items, we have to consider whether the
                 * comment's dependencies are satisfied, so skip it for now.
                 */
                if (skipped_some)
                    do_now = false;
            }
        }
 
        /*
         * Also skip items that need to be forced into later passes.  We need
         * not set skipped_some in this case, since by assumption no main-pass
         * items could depend on these.
         */
        if (_tocEntryRestorePass(next_work_item) != RESTORE_PASS_MAIN)
            do_now = false;
 
        if (do_now)
        {
            /* OK, restore the item and update its dependencies */
            pg_log_info("processing item %d %s %s",
                        next_work_item->dumpId,
                        next_work_item->desc, next_work_item->tag);
 
            (void) restore_toc_entry(AH, next_work_item, false);
 
            /* Reduce dependencies, but don't move anything to ready_heap */
            reduce_dependencies(AH, next_work_item, NULL);
        }
        else
        {
            /* Nope, so add it to pending_list */
            pending_list_append(pending_list, next_work_item);
        }
    }
 
    /*
     * In --transaction-size mode, we must commit the open transaction before
     * dropping the database connection.  This also ensures that child workers
     * can see the objects we've created so far.
     */
    if (AH->public.ropt->txn_size > 0)
        CommitTransaction(&AH->public);
 
    /*
     * Now close parent connection in prep for parallel steps.  We do this
     * mainly to ensure that we don't exceed the specified number of parallel
     * connections.
     */
    DisconnectDatabase(&AH->public);
 
    /* blow away any transient state from the old connection */
    free(AH->currUser);
    AH->currUser = NULL;
    free(AH->currSchema);
    AH->currSchema = NULL;
    free(AH->currTablespace);
    AH->currTablespace = NULL;
    free(AH->currTableAm);
    AH->currTableAm = NULL;
}
 
/*
 * Main engine for parallel restore.
 *
 * Parallel restore is done in three phases.  In this second phase,
 * we process entries by dispatching them to parallel worker children
 * (processes on Unix, threads on Windows), each of which connects
 * separately to the database.  Inter-entry dependencies are respected,
 * and so is the RestorePass multi-pass structure.  When we can no longer
 * make any entries ready to process, we exit.  Normally, there will be
 * nothing left to do; but if there is, the third phase will mop up.
 */
static void
restore_toc_entries_parallel(ArchiveHandle *AH, ParallelState *pstate,
                             TocEntry *pending_list)
{
    binaryheap *ready_heap;
    TocEntry   *next_work_item;
 
    pg_log_debug("entering restore_toc_entries_parallel");
 
    /* Set up ready_heap with enough room for all known TocEntrys */
    ready_heap = binaryheap_allocate(AH->tocCount,
                                     TocEntrySizeCompareBinaryheap,
                                     NULL);
 
    /*
     * The pending_list contains all items that we need to restore.  Move all
     * items that are available to process immediately into the ready_heap.
     * After this setup, the pending list is everything that needs to be done
     * but is blocked by one or more dependencies, while the ready heap
     * contains items that have no remaining dependencies and are OK to
     * process in the current restore pass.
     */
    AH->restorePass = RESTORE_PASS_MAIN;
    move_to_ready_heap(pending_list, ready_heap, AH->restorePass);
 
    /*
     * main parent loop
     *
     * Keep going until there is no worker still running AND there is no work
     * left to be done.  Note invariant: at top of loop, there should always
     * be at least one worker available to dispatch a job to.
     */
    pg_log_info("entering main parallel loop");
 
    for (;;)
    {
        /* Look for an item ready to be dispatched to a worker */
        next_work_item = pop_next_work_item(ready_heap, pstate);
        if (next_work_item != NULL)
        {
            /* If not to be restored, don't waste time launching a worker */
            if ((next_work_item->reqs & (REQ_SCHEMA | REQ_DATA | REQ_STATS)) == 0)
            {
                pg_log_info("skipping item %d %s %s",
                            next_work_item->dumpId,
                            next_work_item->desc, next_work_item->tag);
                /* Update its dependencies as though we'd completed it */
                reduce_dependencies(AH, next_work_item, ready_heap);
                /* Loop around to see if anything else can be dispatched */
                continue;
            }
 
            pg_log_info("launching item %d %s %s",
                        next_work_item->dumpId,
                        next_work_item->desc, next_work_item->tag);
 
            /* Dispatch to some worker */
            DispatchJobForTocEntry(AH, pstate, next_work_item, ACT_RESTORE,
                                   mark_restore_job_done, ready_heap);
        }
        else if (IsEveryWorkerIdle(pstate))
        {
            /*
             * Nothing is ready and no worker is running, so we're done with
             * the current pass or maybe with the whole process.
             */
            if (AH->restorePass == RESTORE_PASS_LAST)
                break;          /* No more parallel processing is possible */
 
            /* Advance to next restore pass */
            AH->restorePass++;
            /* That probably allows some stuff to be made ready */
            move_to_ready_heap(pending_list, ready_heap, AH->restorePass);
            /* Loop around to see if anything's now ready */
            continue;
        }
        else
        {
            /*
             * We have nothing ready, but at least one child is working, so
             * wait for some subjob to finish.
             */
        }
 
        /*
         * Before dispatching another job, check to see if anything has
         * finished.  We should check every time through the loop so as to
         * reduce dependencies as soon as possible.  If we were unable to
         * dispatch any job this time through, wait until some worker finishes
         * (and, hopefully, unblocks some pending item).  If we did dispatch
         * something, continue as soon as there's at least one idle worker.
         * Note that in either case, there's guaranteed to be at least one
         * idle worker when we return to the top of the loop.  This ensures we
         * won't block inside DispatchJobForTocEntry, which would be
         * undesirable: we'd rather postpone dispatching until we see what's
         * been unblocked by finished jobs.
         */
        WaitForWorkers(AH, pstate,
                       next_work_item ? WFW_ONE_IDLE : WFW_GOT_STATUS);
    }
 
    /* There should now be nothing in ready_heap. */
    Assert(binaryheap_empty(ready_heap));
 
    binaryheap_free(ready_heap);
 
    pg_log_info("finished main parallel loop");
}
 
/*
 * Main engine for parallel restore.
 *
 * Parallel restore is done in three phases.  In this third phase,
 * we mop up any remaining TOC entries by processing them serially.
 * This phase normally should have nothing to do, but if we've somehow
 * gotten stuck due to circular dependencies or some such, this provides
 * at least some chance of completing the restore successfully.
 */
static void
restore_toc_entries_postfork(ArchiveHandle *AH, TocEntry *pending_list)
{
    RestoreOptions *ropt = AH->public.ropt;
    TocEntry   *te;
 
    pg_log_debug("entering restore_toc_entries_postfork");
 
    /*
     * Now reconnect the single parent connection.
     */
    ConnectDatabaseAhx((Archive *) AH, &ropt->cparams, true);
 
    /* re-establish fixed state */
    _doSetFixedOutputState(AH);
 
    /*
     * Make sure there is no work left due to, say, circular dependencies, or
     * some other pathological condition.  If so, do it in the single parent
     * connection.  We don't sweat about RestorePass ordering; it's likely we
     * already violated that.
     */
    for (te = pending_list->pending_next; te != pending_list; te = te->pending_next)
    {
        pg_log_info("processing missed item %d %s %s",
                    te->dumpId, te->desc, te->tag);
        (void) restore_toc_entry(AH, te, false);
    }
}
 
/*
 * Check if te1 has an exclusive lock requirement for an item that te2 also
 * requires, whether or not te2's requirement is for an exclusive lock.
 */
static bool
has_lock_conflicts(TocEntry *te1, TocEntry *te2)
{
    int         j,
                k;
 
    for (j = 0; j < te1->nLockDeps; j++)
    {
        for (k = 0; k < te2->nDeps; k++)
        {
            if (te1->lockDeps[j] == te2->dependencies[k])
                return true;
        }
    }
    return false;
}
 
 
/*
 * Initialize the header of the pending-items list.
 *
 * This is a circular list with a dummy TocEntry as header, just like the
 * main TOC list; but we use separate list links so that an entry can be in
 * the main TOC list as well as in the pending list.
 */
static void
pending_list_header_init(TocEntry *l)
{
    l->pending_prev = l->pending_next = l;
}
 
/* Append te to the end of the pending-list headed by l */
static void
pending_list_append(TocEntry *l, TocEntry *te)
{
    te->pending_prev = l->pending_prev;
    l->pending_prev->pending_next = te;
    l->pending_prev = te;
    te->pending_next = l;
}
 
/* Remove te from the pending-list */
static void
pending_list_remove(TocEntry *te)
{
    te->pending_prev->pending_next = te->pending_next;
    te->pending_next->pending_prev = te->pending_prev;
    te->pending_prev = NULL;
    te->pending_next = NULL;
}
 
 
/* qsort comparator for sorting TocEntries by dataLength */
static int
TocEntrySizeCompareQsort(const void *p1, const void *p2)
{
    const TocEntry *te1 = *(const TocEntry *const *) p1;
    const TocEntry *te2 = *(const TocEntry *const *) p2;
 
    /* Sort by decreasing dataLength */
    if (te1->dataLength > te2->dataLength)
        return -1;
    if (te1->dataLength < te2->dataLength)
        return 1;
 
    /* For equal dataLengths, sort by dumpId, just to be stable */
    if (te1->dumpId < te2->dumpId)
        return -1;
    if (te1->dumpId > te2->dumpId)
        return 1;
 
    return 0;
}
 
/* binaryheap comparator for sorting TocEntries by dataLength */
static int
TocEntrySizeCompareBinaryheap(void *p1, void *p2, void *arg)
{
    /* return opposite of qsort comparator for max-heap */
    return -TocEntrySizeCompareQsort(&p1, &p2);
}
 
 
/*
 * Move all immediately-ready items from pending_list to ready_heap.
 *
 * Items are considered ready if they have no remaining dependencies and
 * they belong in the current restore pass.  (See also reduce_dependencies,
 * which applies the same logic one-at-a-time.)
 */
static void
move_to_ready_heap(TocEntry *pending_list,
                   binaryheap *ready_heap,
                   RestorePass pass)
{
    TocEntry   *te;
    TocEntry   *next_te;
 
    for (te = pending_list->pending_next; te != pending_list; te = next_te)
    {
        /* must save list link before possibly removing te from list */
        next_te = te->pending_next;
 
        if (te->depCount == 0 &&
            _tocEntryRestorePass(te) == pass)
        {
            /* Remove it from pending_list ... */
            pending_list_remove(te);
            /* ... and add to ready_heap */
            binaryheap_add(ready_heap, te);
        }
    }
}
 
/*
 * Find the next work item (if any) that is capable of being run now,
 * and remove it from the ready_heap.
 *
 * Returns the item, or NULL if nothing is runnable.
 *
 * To qualify, the item must have no remaining dependencies
 * and no requirements for locks that are incompatible with
 * items currently running.  Items in the ready_heap are known to have
 * no remaining dependencies, but we have to check for lock conflicts.
 */
static TocEntry *
pop_next_work_item(binaryheap *ready_heap,
                   ParallelState *pstate)
{
    /*
     * Search the ready_heap until we find a suitable item.  Note that we do a
     * sequential scan through the heap nodes, so even though we will first
     * try to choose the highest-priority item, we might end up picking
     * something with a much lower priority.  However, we expect that we will
     * typically be able to pick one of the first few items, which should
     * usually have a relatively high priority.
     */
    for (int i = 0; i < binaryheap_size(ready_heap); i++)
    {
        TocEntry   *te = (TocEntry *) binaryheap_get_node(ready_heap, i);
        bool        conflicts = false;
 
        /*
         * Check to see if the item would need exclusive lock on something
         * that a currently running item also needs lock on, or vice versa. If
         * so, we don't want to schedule them together.
         */
        for (int k = 0; k < pstate->numWorkers; k++)
        {
            TocEntry   *running_te = pstate->te[k];
 
            if (running_te == NULL)
                continue;
            if (has_lock_conflicts(te, running_te) ||
                has_lock_conflicts(running_te, te))
            {
                conflicts = true;
                break;
            }
        }
 
        if (conflicts)
            continue;
 
        /* passed all tests, so this item can run */
        binaryheap_remove_node(ready_heap, i);
        return te;
    }
 
    pg_log_debug("no item ready");
    return NULL;
}
 
 
/*
 * Restore a single TOC item in parallel with others
 *
 * this is run in the worker, i.e. in a thread (Windows) or a separate process
 * (everything else). A worker process executes several such work items during
 * a parallel backup or restore. Once we terminate here and report back that
 * our work is finished, the leader process will assign us a new work item.
 */
int
parallel_restore(ArchiveHandle *AH, TocEntry *te)
{
    int         status;
 
    Assert(AH->connection != NULL);
 
    /* Count only errors associated with this TOC entry */
    AH->public.n_errors = 0;
 
    /* Restore the TOC item */
    status = restore_toc_entry(AH, te, true);
 
    return status;
}
 
 
/*
 * Callback function that's invoked in the leader process after a step has
 * been parallel restored.
 *
 * Update status and reduce the dependency count of any dependent items.
 */
static void
mark_restore_job_done(ArchiveHandle *AH,
                      TocEntry *te,
                      int status,
                      void *callback_data)
{
    binaryheap *ready_heap = (binaryheap *) callback_data;
 
    pg_log_info("finished item %d %s %s",
                te->dumpId, te->desc, te->tag);
 
    if (status == WORKER_CREATE_DONE)
        mark_create_done(AH, te);
    else if (status == WORKER_INHIBIT_DATA)
    {
        inhibit_data_for_failed_table(AH, te);
        AH->public.n_errors++;
    }
    else if (status == WORKER_IGNORED_ERRORS)
        AH->public.n_errors++;
    else if (status != 0)
        pg_fatal("worker process failed: exit code %d",
                 status);
 
    reduce_dependencies(AH, te, ready_heap);
}
 
 
/*
 * Process the dependency information into a form useful for parallel restore.
 *
 * This function takes care of fixing up some missing or badly designed
 * dependencies, and then prepares subsidiary data structures that will be
 * used in the main parallel-restore logic, including:
 * 1. We build the revDeps[] arrays of incoming dependency dumpIds.
 * 2. We set up depCount fields that are the number of as-yet-unprocessed
 * dependencies for each TOC entry.
 *
 * We also identify locking dependencies so that we can avoid trying to
 * schedule conflicting items at the same time.
 */
static void
fix_dependencies(ArchiveHandle *AH)
{
    TocEntry   *te;
    int         i;
 
    /*
     * Initialize the depCount/revDeps/nRevDeps fields, and make sure the TOC
     * items are marked as not being in any parallel-processing list.
     */
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        te->depCount = te->nDeps;
        te->revDeps = NULL;
        te->nRevDeps = 0;
        te->pending_prev = NULL;
        te->pending_next = NULL;
    }
 
    /*
     * POST_DATA items that are shown as depending on a table need to be
     * re-pointed to depend on that table's data, instead.  This ensures they
     * won't get scheduled until the data has been loaded.
     */
    repoint_table_dependencies(AH);
 
    /*
     * Pre-8.4 versions of pg_dump neglected to set up a dependency from BLOB
     * COMMENTS to BLOBS.  Cope.  (We assume there's only one BLOBS and only
     * one BLOB COMMENTS in such files.)
     */
    if (AH->version < K_VERS_1_11)
    {
        for (te = AH->toc->next; te != AH->toc; te = te->next)
        {
            if (strcmp(te->desc, "BLOB COMMENTS") == 0 && te->nDeps == 0)
            {
                TocEntry   *te2;
 
                for (te2 = AH->toc->next; te2 != AH->toc; te2 = te2->next)
                {
                    if (strcmp(te2->desc, "BLOBS") == 0)
                    {
                        te->dependencies = (DumpId *) pg_malloc(sizeof(DumpId));
                        te->dependencies[0] = te2->dumpId;
                        te->nDeps++;
                        te->depCount++;
                        break;
                    }
                }
                break;
            }
        }
    }
 
    /*
     * At this point we start to build the revDeps reverse-dependency arrays,
     * so all changes of dependencies must be complete.
     */
 
    /*
     * Count the incoming dependencies for each item.  Also, it is possible
     * that the dependencies list items that are not in the archive at all
     * (that should not happen in 9.2 and later, but is highly likely in older
     * archives).  Subtract such items from the depCounts.
     */
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        for (i = 0; i < te->nDeps; i++)
        {
            DumpId      depid = te->dependencies[i];
 
            if (depid <= AH->maxDumpId && AH->tocsByDumpId[depid] != NULL)
                AH->tocsByDumpId[depid]->nRevDeps++;
            else
                te->depCount--;
        }
    }
 
    /*
     * Allocate space for revDeps[] arrays, and reset nRevDeps so we can use
     * it as a counter below.
     */
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        if (te->nRevDeps > 0)
            te->revDeps = (DumpId *) pg_malloc(te->nRevDeps * sizeof(DumpId));
        te->nRevDeps = 0;
    }
 
    /*
     * Build the revDeps[] arrays of incoming-dependency dumpIds.  This had
     * better agree with the loops above.
     */
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        for (i = 0; i < te->nDeps; i++)
        {
            DumpId      depid = te->dependencies[i];
 
            if (depid <= AH->maxDumpId && AH->tocsByDumpId[depid] != NULL)
            {
                TocEntry   *otherte = AH->tocsByDumpId[depid];
 
                otherte->revDeps[otherte->nRevDeps++] = te->dumpId;
            }
        }
    }
 
    /*
     * Lastly, work out the locking dependencies.
     */
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        te->lockDeps = NULL;
        te->nLockDeps = 0;
        identify_locking_dependencies(AH, te);
    }
}
 
/*
 * Change dependencies on table items to depend on table data items instead,
 * but only in POST_DATA items.
 *
 * Also, for any item having such dependency(s), set its dataLength to the
 * largest dataLength of the table data items it depends on.  This ensures
 * that parallel restore will prioritize larger jobs (index builds, FK
 * constraint checks, etc) over smaller ones, avoiding situations where we
 * end a restore with only one active job working on a large table.
 */
static void
repoint_table_dependencies(ArchiveHandle *AH)
{
    TocEntry   *te;
    int         i;
    DumpId      olddep;
 
    for (te = AH->toc->next; te != AH->toc; te = te->next)
    {
        if (te->section != SECTION_POST_DATA)
            continue;
        for (i = 0; i < te->nDeps; i++)
        {
            olddep = te->dependencies[i];
            if (olddep <= AH->maxDumpId &&
                AH->tableDataId[olddep] != 0)
            {
                DumpId      tabledataid = AH->tableDataId[olddep];
                TocEntry   *tabledatate = AH->tocsByDumpId[tabledataid];
 
                te->dependencies[i] = tabledataid;
                te->dataLength = Max(te->dataLength, tabledatate->dataLength);
                pg_log_debug("transferring dependency %d -> %d to %d",
                             te->dumpId, olddep, tabledataid);
            }
        }
    }
}
 
/*
 * Identify which objects we'll need exclusive lock on in order to restore
 * the given TOC entry (*other* than the one identified by the TOC entry
 * itself).  Record their dump IDs in the entry's lockDeps[] array.
 */
static void
identify_locking_dependencies(ArchiveHandle *AH, TocEntry *te)
{
    DumpId     *lockids;
    int         nlockids;
    int         i;
 
    /*
     * We only care about this for POST_DATA items.  PRE_DATA items are not
     * run in parallel, and DATA items are all independent by assumption.
     */
    if (te->section != SECTION_POST_DATA)
        return;
 
    /* Quick exit if no dependencies at all */
    if (te->nDeps == 0)
        return;
 
    /*
     * Most POST_DATA items are ALTER TABLEs or some moral equivalent of that,
     * and hence require exclusive lock.  However, we know that CREATE INDEX
     * does not.  (Maybe someday index-creating CONSTRAINTs will fall in that
     * category too ... but today is not that day.)
     */
    if (strcmp(te->desc, "INDEX") == 0)
        return;
 
    /*
     * We assume the entry requires exclusive lock on each TABLE or TABLE DATA
     * item listed among its dependencies.  Originally all of these would have
     * been TABLE items, but repoint_table_dependencies would have repointed
     * them to the TABLE DATA items if those are present (which they might not
     * be, eg in a schema-only dump).  Note that all of the entries we are
     * processing here are POST_DATA; otherwise there might be a significant
     * difference between a dependency on a table and a dependency on its
     * data, so that closer analysis would be needed here.
     */
    lockids = (DumpId *) pg_malloc(te->nDeps * sizeof(DumpId));
    nlockids = 0;
    for (i = 0; i < te->nDeps; i++)
    {
        DumpId      depid = te->dependencies[i];
 
        if (depid <= AH->maxDumpId && AH->tocsByDumpId[depid] != NULL &&
            ((strcmp(AH->tocsByDumpId[depid]->desc, "TABLE DATA") == 0) ||
             strcmp(AH->tocsByDumpId[depid]->desc, "TABLE") == 0))
            lockids[nlockids++] = depid;
    }
 
    if (nlockids == 0)
    {
        free(lockids);
        return;
    }
 
    te->lockDeps = pg_realloc(lockids, nlockids * sizeof(DumpId));
    te->nLockDeps = nlockids;
}
 
/*
 * Remove the specified TOC entry from the depCounts of items that depend on
 * it, thereby possibly making them ready-to-run.  Any pending item that
 * becomes ready should be moved to the ready_heap, if that's provided.
 */
static void
reduce_dependencies(ArchiveHandle *AH, TocEntry *te,
                    binaryheap *ready_heap)
{
    int         i;
 
    pg_log_debug("reducing dependencies for %d", te->dumpId);
 
    for (i = 0; i < te->nRevDeps; i++)
    {
        TocEntry   *otherte = AH->tocsByDumpId[te->revDeps[i]];
 
        Assert(otherte->depCount > 0);
        otherte->depCount--;
 
        /*
         * It's ready if it has no remaining dependencies, and it belongs in
         * the current restore pass, and it is currently a member of the
         * pending list (that check is needed to prevent double restore in
         * some cases where a list-file forces out-of-order restoring).
         * However, if ready_heap == NULL then caller doesn't want any list
         * memberships changed.
         */
        if (otherte->depCount == 0 &&
            _tocEntryRestorePass(otherte) == AH->restorePass &&
            otherte->pending_prev != NULL &&
            ready_heap != NULL)
        {
            /* Remove it from pending list ... */
            pending_list_remove(otherte);
            /* ... and add to ready_heap */
            binaryheap_add(ready_heap, otherte);
        }
    }
}
 
/*
 * Set the created flag on the DATA member corresponding to the given
 * TABLE member
 */
static void
mark_create_done(ArchiveHandle *AH, TocEntry *te)
{
    if (AH->tableDataId[te->dumpId] != 0)
    {
        TocEntry   *ted = AH->tocsByDumpId[AH->tableDataId[te->dumpId]];
 
        ted->created = true;
    }
}
 
/*
 * Mark the DATA member corresponding to the given TABLE member
 * as not wanted
 */
static void
inhibit_data_for_failed_table(ArchiveHandle *AH, TocEntry *te)
{
    pg_log_info("table \"%s\" could not be created, will not restore its data",
                te->tag);
 
    if (AH->tableDataId[te->dumpId] != 0)
    {
        TocEntry   *ted = AH->tocsByDumpId[AH->tableDataId[te->dumpId]];
 
        ted->reqs = 0;
    }
}
 
/*
 * Clone and de-clone routines used in parallel restoration.
 *
 * Enough of the structure is cloned to ensure that there is no
 * conflict between different threads each with their own clone.
 */
ArchiveHandle *
CloneArchive(ArchiveHandle *AH)
{
    ArchiveHandle *clone;
 
    /* Make a "flat" copy */
    clone = (ArchiveHandle *) pg_malloc(sizeof(ArchiveHandle));
    memcpy(clone, AH, sizeof(ArchiveHandle));
 
    /* Likewise flat-copy the RestoreOptions, so we can alter them locally */
    clone->public.ropt = (RestoreOptions *) pg_malloc(sizeof(RestoreOptions));
    memcpy(clone->public.ropt, AH->public.ropt, sizeof(RestoreOptions));
 
    /* Handle format-independent fields */
    memset(&(clone->sqlparse), 0, sizeof(clone->sqlparse));
 
    /* The clone will have its own connection, so disregard connection state */
    clone->connection = NULL;
    clone->connCancel = NULL;
    clone->currUser = NULL;
    clone->currSchema = NULL;
    clone->currTableAm = NULL;
    clone->currTablespace = NULL;
 
    /* savedPassword must be local in case we change it while connecting */
    if (clone->savedPassword)
        clone->savedPassword = pg_strdup(clone->savedPassword);
 
    /* clone has its own error count, too */
    clone->public.n_errors = 0;
 
    /* clones should not share lo_buf */
    clone->lo_buf = NULL;
 
    /*
     * Clone connections disregard --transaction-size; they must commit after
     * each command so that the results are immediately visible to other
     * workers.
     */
    clone->public.ropt->txn_size = 0;
 
    /*
     * Connect our new clone object to the database, using the same connection
     * parameters used for the original connection.
     */
    ConnectDatabaseAhx((Archive *) clone, &clone->public.ropt->cparams, true);
 
    /* re-establish fixed state */
    if (AH->mode == archModeRead)
        _doSetFixedOutputState(clone);
    /* in write case, setupDumpWorker will fix up connection state */
 
    /* Let the format-specific code have a chance too */
    clone->ClonePtr(clone);
 
    Assert(clone->connection != NULL);
    return clone;
}
 
/*
 * Release clone-local storage.
 *
 * Note: we assume any clone-local connection was already closed.
 */
void
DeCloneArchive(ArchiveHandle *AH)
{
    /* Should not have an open database connection */
    Assert(AH->connection == NULL);
 
    /* Clear format-specific state */
    AH->DeClonePtr(AH);
 
    /* Clear state allocated by CloneArchive */
    if (AH->sqlparse.curCmd)
        destroyPQExpBuffer(AH->sqlparse.curCmd);
 
    /* Clear any connection-local state */
    free(AH->currUser);
    free(AH->currSchema);
    free(AH->currTablespace);
    free(AH->currTableAm);
    free(AH->savedPassword);
 
    free(AH);
}