copyto.c File Reference

#include "postgres.h"
#include <ctype.h>
#include <unistd.h>
#include <sys/stat.h>
#include "access/heapam.h"
#include "access/htup_details.h"
#include "access/tableam.h"
#include "access/xact.h"
#include "access/xlog.h"
#include "commands/copy.h"
#include "commands/progress.h"
#include "executor/execdesc.h"
#include "executor/executor.h"
#include "executor/tuptable.h"
#include "libpq/libpq.h"
#include "libpq/pqformat.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "optimizer/optimizer.h"
#include "pgstat.h"
#include "rewrite/rewriteHandler.h"
#include "storage/fd.h"
#include "tcop/tcopprot.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/partcache.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"

Include dependency graph for copyto.c:

Go to the source code of this file.

Data Structures
struct	CopyToStateData
struct	DR_copy

Macros
#define	DUMPSOFAR()

Typedefs
typedef enum CopyDest	CopyDest
typedef struct CopyToStateData	CopyToStateData

Enumerations
enum	CopyDest { COPY_FILE, COPY_FRONTEND }

Functions
static void	EndCopy (CopyToState cstate)
static void	ClosePipeToProgram (CopyToState cstate)
static void	CopyOneRowTo (CopyToState cstate, TupleTableSlot *slot)
static void	CopyAttributeOutText (CopyToState cstate, char *string)
static void	CopyAttributeOutCSV (CopyToState cstate, char *string, bool use_quote, bool single_attr)
static void	SendCopyBegin (CopyToState cstate)
static void	SendCopyEnd (CopyToState cstate)
static void	CopySendData (CopyToState cstate, const void *databuf, int datasize)
static void	CopySendString (CopyToState cstate, const char *str)
static void	CopySendChar (CopyToState cstate, char c)
static void	CopySendEndOfRow (CopyToState cstate)
static void	CopySendInt32 (CopyToState cstate, int32 val)
static void	CopySendInt16 (CopyToState cstate, int16 val)
CopyToState	BeginCopyTo (ParseState *pstate, Relation rel, RawStmt *raw_query, Oid queryRelId, const char *filename, bool is_program, List *attnamelist, List *options)
void	EndCopyTo (CopyToState cstate)
uint64	DoCopyTo (CopyToState cstate)
static void	copy_dest_startup (DestReceiver *self, int operation, TupleDesc typeinfo)
static bool	copy_dest_receive (TupleTableSlot *slot, DestReceiver *self)
static void	copy_dest_shutdown (DestReceiver *self)
static void	copy_dest_destroy (DestReceiver *self)
DestReceiver *	CreateCopyDestReceiver (void)

Variables
static const char	BinarySignature [11] = "PGCOPY\n\377\r\n\0"

Macro Definition Documentation

DUMPSOFAR

#define DUMPSOFAR

(

)

Value:

do { \
        if (ptr > start) \
            CopySendData(cstate, start, ptr - start); \
    } while (0)

Definition at line 1005 of file copyto.c.

Referenced by CopyAttributeOutCSV(), and CopyAttributeOutText().

Typedef Documentation

CopyDest

typedef enum CopyDest CopyDest

CopyToStateData

typedef struct CopyToStateData CopyToStateData

Enumeration Type Documentation

CopyDest

enum CopyDest

Enumerator
COPY_FILE
COPY_FRONTEND

Definition at line 50 of file copyto.c.

{
    COPY_FILE,                  /* to file (or a piped program) */
    COPY_FRONTEND,              /* to frontend */
} CopyDest;

Function Documentation

BeginCopyTo()

CopyToState BeginCopyTo	(	ParseState *	pstate,
		Relation	rel,
		RawStmt *	raw_query,
		Oid	queryRelId,
		const char *	filename,
		bool	is_program,
		List *	attnamelist,
		List *	options
	)

Definition at line 342 of file copyto.c.

References AllocateFile(), ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, Assert, attnum, CopyToStateData::attnumlist, CopyToStateData::bytes_processed, CMD_DELETE, CMD_INSERT, CMD_SELECT, CMD_UPDATE, Query::commandType, CopyToStateData::copy_dest, COPY_FILE, CopyToStateData::copy_file, CopyToStateData::copycontext, CopyGetAttnums(), CreateDestReceiver(), CreateQueryDesc(), cur, CurrentMemoryContext, CURSOR_OPT_PARALLEL_OK, generate_unaccent_rules::dest, DestCopyOut, DestRemote, CopyToStateData::encoding_embeds_ascii, ereport, errcode(), errcode_for_file_access(), errhint(), errmsg(), ERROR, ExecutorStart(), CopyFormatOptions::file_encoding, CopyToStateData::file_encoding, CopyToStateData::filename, CopyFormatOptions::force_notnull, CopyFormatOptions::force_notnull_flags, CopyFormatOptions::force_null, CopyFormatOptions::force_null_flags, CopyFormatOptions::force_quote, CopyFormatOptions::force_quote_all, CopyFormatOptions::force_quote_flags, fstat, GetActiveSnapshot(), GetDatabaseEncoding(), i, InvalidOid, InvalidSnapshot, is_absolute_path, CopyToStateData::is_program, IsA, lfirst_int, lfirst_node, linitial_node, list_length(), list_member_int(), list_member_oid(), MemoryContextSwitchTo(), NameStr, TupleDescData::natts, CopyToStateData::need_transcoding, NIL, OpenPipeStream(), CopyToStateData::opts, ParseState::p_sourcetext, palloc0(), pg_analyze_and_rewrite(), PG_BINARY_W, pg_database_encoding_max_length(), PG_ENCODING_IS_CLIENT_ONLY, PG_END_TRY, PG_FINALLY, pg_get_client_encoding(), pg_plan_query(), PG_TRY, pgstat_progress_start_command(), pgstat_progress_update_multi_param(), ProcessCopyOptions(), PROGRESS_COMMAND_COPY, PROGRESS_COPY_COMMAND, PROGRESS_COPY_COMMAND_TO, PROGRESS_COPY_TYPE, PROGRESS_COPY_TYPE_FILE, PROGRESS_COPY_TYPE_PIPE, PROGRESS_COPY_TYPE_PROGRAM, pstrdup(), PushCopiedSnapshot(), QSRC_NON_INSTEAD_RULE, QSRC_QUAL_INSTEAD_RULE, CopyToStateData::queryDesc, Query::querySource, RelationData::rd_rel, CopyToStateData::rel, RelationGetDescr, RelationGetRelationName, RelationGetRelid, PlannedStmt::relationOids, Query::returningList, S_ISDIR, S_IWGRP, S_IWOTH, stat::st_mode, generate_unaccent_rules::stdout, QueryDesc::tupDesc, TupleDescAttr, UpdateActiveSnapshotCommandId(), Query::utilityStmt, and whereToSendOutput.

Referenced by DoCopy().

{
    CopyToState cstate;
    bool        pipe = (filename == NULL);
    TupleDesc   tupDesc;
    int         num_phys_attrs;
    MemoryContext oldcontext;
    const int   progress_cols[] = {
        PROGRESS_COPY_COMMAND,
        PROGRESS_COPY_TYPE
    };
    int64       progress_vals[] = {
        PROGRESS_COPY_COMMAND_TO,
        0
    };

    if (rel != NULL && rel->rd_rel->relkind != RELKIND_RELATION)
    {
        if (rel->rd_rel->relkind == RELKIND_VIEW)
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("cannot copy from view \"%s\"",
                            RelationGetRelationName(rel)),
                     errhint("Try the COPY (SELECT ...) TO variant.")));
        else if (rel->rd_rel->relkind == RELKIND_MATVIEW)
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("cannot copy from materialized view \"%s\"",
                            RelationGetRelationName(rel)),
                     errhint("Try the COPY (SELECT ...) TO variant.")));
        else if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("cannot copy from foreign table \"%s\"",
                            RelationGetRelationName(rel)),
                     errhint("Try the COPY (SELECT ...) TO variant.")));
        else if (rel->rd_rel->relkind == RELKIND_SEQUENCE)
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("cannot copy from sequence \"%s\"",
                            RelationGetRelationName(rel))));
        else if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("cannot copy from partitioned table \"%s\"",
                            RelationGetRelationName(rel)),
                     errhint("Try the COPY (SELECT ...) TO variant.")));
        else
            ereport(ERROR,
                    (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                     errmsg("cannot copy from non-table relation \"%s\"",
                            RelationGetRelationName(rel))));
    }


    /* Allocate workspace and zero all fields */
    cstate = (CopyToStateData *) palloc0(sizeof(CopyToStateData));

    /*
     * We allocate everything used by a cstate in a new memory context. This
     * avoids memory leaks during repeated use of COPY in a query.
     */
    cstate->copycontext = AllocSetContextCreate(CurrentMemoryContext,
                                                "COPY",
                                                ALLOCSET_DEFAULT_SIZES);

    oldcontext = MemoryContextSwitchTo(cstate->copycontext);

    /* Extract options from the statement node tree */
    ProcessCopyOptions(pstate, &cstate->opts, false /* is_from */ , options);

    /* Process the source/target relation or query */
    if (rel)
    {
        Assert(!raw_query);

        cstate->rel = rel;

        tupDesc = RelationGetDescr(cstate->rel);
    }
    else
    {
        List       *rewritten;
        Query      *query;
        PlannedStmt *plan;
        DestReceiver *dest;

        cstate->rel = NULL;

        /*
         * Run parse analysis and rewrite.  Note this also acquires sufficient
         * locks on the source table(s).
         */
        rewritten = pg_analyze_and_rewrite(raw_query,
                                           pstate->p_sourcetext, NULL, 0,
                                           NULL);

        /* check that we got back something we can work with */
        if (rewritten == NIL)
        {
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("DO INSTEAD NOTHING rules are not supported for COPY")));
        }
        else if (list_length(rewritten) > 1)
        {
            ListCell   *lc;

            /* examine queries to determine which error message to issue */
            foreach(lc, rewritten)
            {
                Query      *q = lfirst_node(Query, lc);

                if (q->querySource == QSRC_QUAL_INSTEAD_RULE)
                    ereport(ERROR,
                            (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                             errmsg("conditional DO INSTEAD rules are not supported for COPY")));
                if (q->querySource == QSRC_NON_INSTEAD_RULE)
                    ereport(ERROR,
                            (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                             errmsg("DO ALSO rules are not supported for the COPY")));
            }

            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("multi-statement DO INSTEAD rules are not supported for COPY")));
        }

        query = linitial_node(Query, rewritten);

        /* The grammar allows SELECT INTO, but we don't support that */
        if (query->utilityStmt != NULL &&
            IsA(query->utilityStmt, CreateTableAsStmt))
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("COPY (SELECT INTO) is not supported")));

        Assert(query->utilityStmt == NULL);

        /*
         * Similarly the grammar doesn't enforce the presence of a RETURNING
         * clause, but this is required here.
         */
        if (query->commandType != CMD_SELECT &&
            query->returningList == NIL)
        {
            Assert(query->commandType == CMD_INSERT ||
                   query->commandType == CMD_UPDATE ||
                   query->commandType == CMD_DELETE);

            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                     errmsg("COPY query must have a RETURNING clause")));
        }

        /* plan the query */
        plan = pg_plan_query(query, pstate->p_sourcetext,
                             CURSOR_OPT_PARALLEL_OK, NULL);

        /*
         * With row-level security and a user using "COPY relation TO", we
         * have to convert the "COPY relation TO" to a query-based COPY (eg:
         * "COPY (SELECT * FROM relation) TO"), to allow the rewriter to add
         * in any RLS clauses.
         *
         * When this happens, we are passed in the relid of the originally
         * found relation (which we have locked).  As the planner will look up
         * the relation again, we double-check here to make sure it found the
         * same one that we have locked.
         */
        if (queryRelId != InvalidOid)
        {
            /*
             * Note that with RLS involved there may be multiple relations,
             * and while the one we need is almost certainly first, we don't
             * make any guarantees of that in the planner, so check the whole
             * list and make sure we find the original relation.
             */
            if (!list_member_oid(plan->relationOids, queryRelId))
                ereport(ERROR,
                        (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                         errmsg("relation referenced by COPY statement has changed")));
        }

        /*
         * Use a snapshot with an updated command ID to ensure this query sees
         * results of any previously executed queries.
         */
        PushCopiedSnapshot(GetActiveSnapshot());
        UpdateActiveSnapshotCommandId();

        /* Create dest receiver for COPY OUT */
        dest = CreateDestReceiver(DestCopyOut);
        ((DR_copy *) dest)->cstate = cstate;

        /* Create a QueryDesc requesting no output */
        cstate->queryDesc = CreateQueryDesc(plan, pstate->p_sourcetext,
                                            GetActiveSnapshot(),
                                            InvalidSnapshot,
                                            dest, NULL, NULL, 0);

        /*
         * Call ExecutorStart to prepare the plan for execution.
         *
         * ExecutorStart computes a result tupdesc for us
         */
        ExecutorStart(cstate->queryDesc, 0);

        tupDesc = cstate->queryDesc->tupDesc;
    }

    /* Generate or convert list of attributes to process */
    cstate->attnumlist = CopyGetAttnums(tupDesc, cstate->rel, attnamelist);

    num_phys_attrs = tupDesc->natts;

    /* Convert FORCE_QUOTE name list to per-column flags, check validity */
    cstate->opts.force_quote_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
    if (cstate->opts.force_quote_all)
    {
        int         i;

        for (i = 0; i < num_phys_attrs; i++)
            cstate->opts.force_quote_flags[i] = true;
    }
    else if (cstate->opts.force_quote)
    {
        List       *attnums;
        ListCell   *cur;

        attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->opts.force_quote);

        foreach(cur, attnums)
        {
            int         attnum = lfirst_int(cur);
            Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);

            if (!list_member_int(cstate->attnumlist, attnum))
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                         errmsg("FORCE_QUOTE column \"%s\" not referenced by COPY",
                                NameStr(attr->attname))));
            cstate->opts.force_quote_flags[attnum - 1] = true;
        }
    }

    /* Convert FORCE_NOT_NULL name list to per-column flags, check validity */
    cstate->opts.force_notnull_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
    if (cstate->opts.force_notnull)
    {
        List       *attnums;
        ListCell   *cur;

        attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->opts.force_notnull);

        foreach(cur, attnums)
        {
            int         attnum = lfirst_int(cur);
            Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);

            if (!list_member_int(cstate->attnumlist, attnum))
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                         errmsg("FORCE_NOT_NULL column \"%s\" not referenced by COPY",
                                NameStr(attr->attname))));
            cstate->opts.force_notnull_flags[attnum - 1] = true;
        }
    }

    /* Convert FORCE_NULL name list to per-column flags, check validity */
    cstate->opts.force_null_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
    if (cstate->opts.force_null)
    {
        List       *attnums;
        ListCell   *cur;

        attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->opts.force_null);

        foreach(cur, attnums)
        {
            int         attnum = lfirst_int(cur);
            Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);

            if (!list_member_int(cstate->attnumlist, attnum))
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
                         errmsg("FORCE_NULL column \"%s\" not referenced by COPY",
                                NameStr(attr->attname))));
            cstate->opts.force_null_flags[attnum - 1] = true;
        }
    }

    /* Use client encoding when ENCODING option is not specified. */
    if (cstate->opts.file_encoding < 0)
        cstate->file_encoding = pg_get_client_encoding();
    else
        cstate->file_encoding = cstate->opts.file_encoding;

    /*
     * Set up encoding conversion info.  Even if the file and server encodings
     * are the same, we must apply pg_any_to_server() to validate data in
     * multibyte encodings.
     */
    cstate->need_transcoding =
        (cstate->file_encoding != GetDatabaseEncoding() ||
         pg_database_encoding_max_length() > 1);
    /* See Multibyte encoding comment above */
    cstate->encoding_embeds_ascii = PG_ENCODING_IS_CLIENT_ONLY(cstate->file_encoding);

    cstate->copy_dest = COPY_FILE;  /* default */

    MemoryContextSwitchTo(oldcontext);

    if (pipe)
    {
        progress_vals[1] = PROGRESS_COPY_TYPE_PIPE;

        Assert(!is_program);    /* the grammar does not allow this */
        if (whereToSendOutput != DestRemote)
            cstate->copy_file = stdout;
    }
    else
    {
        cstate->filename = pstrdup(filename);
        cstate->is_program = is_program;

        if (is_program)
        {
            progress_vals[1] = PROGRESS_COPY_TYPE_PROGRAM;
            cstate->copy_file = OpenPipeStream(cstate->filename, PG_BINARY_W);
            if (cstate->copy_file == NULL)
                ereport(ERROR,
                        (errcode_for_file_access(),
                         errmsg("could not execute command \"%s\": %m",
                                cstate->filename)));
        }
        else
        {
            mode_t      oumask; /* Pre-existing umask value */
            struct stat st;

            progress_vals[1] = PROGRESS_COPY_TYPE_FILE;

            /*
             * Prevent write to relative path ... too easy to shoot oneself in
             * the foot by overwriting a database file ...
             */
            if (!is_absolute_path(filename))
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_NAME),
                         errmsg("relative path not allowed for COPY to file")));

            oumask = umask(S_IWGRP | S_IWOTH);
            PG_TRY();
            {
                cstate->copy_file = AllocateFile(cstate->filename, PG_BINARY_W);
            }
            PG_FINALLY();
            {
                umask(oumask);
            }
            PG_END_TRY();
            if (cstate->copy_file == NULL)
            {
                /* copy errno because ereport subfunctions might change it */
                int         save_errno = errno;

                ereport(ERROR,
                        (errcode_for_file_access(),
                         errmsg("could not open file \"%s\" for writing: %m",
                                cstate->filename),
                         (save_errno == ENOENT || save_errno == EACCES) ?
                         errhint("COPY TO instructs the PostgreSQL server process to write a file. "
                                 "You may want a client-side facility such as psql's \\copy.") : 0));
            }

            if (fstat(fileno(cstate->copy_file), &st))
                ereport(ERROR,
                        (errcode_for_file_access(),
                         errmsg("could not stat file \"%s\": %m",
                                cstate->filename)));

            if (S_ISDIR(st.st_mode))
                ereport(ERROR,
                        (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                         errmsg("\"%s\" is a directory", cstate->filename)));
        }
    }

    /* initialize progress */
    pgstat_progress_start_command(PROGRESS_COMMAND_COPY,
                                  cstate->rel ? RelationGetRelid(cstate->rel) : InvalidOid);
    pgstat_progress_update_multi_param(2, progress_cols, progress_vals);

    cstate->bytes_processed = 0;

    MemoryContextSwitchTo(oldcontext);

    return cstate;
}

ClosePipeToProgram()

static void ClosePipeToProgram ( CopyToState  cstate )

static

Definition at line 292 of file copyto.c.

References Assert, ClosePipeStream(), CopyToStateData::copy_file, ereport, errcode(), errcode_for_file_access(), errdetail_internal(), errmsg(), ERROR, CopyToStateData::filename, CopyToStateData::is_program, and wait_result_to_str().

Referenced by CopySendEndOfRow(), and EndCopy().

{
    int         pclose_rc;

    Assert(cstate->is_program);

    pclose_rc = ClosePipeStream(cstate->copy_file);
    if (pclose_rc == -1)
        ereport(ERROR,
                (errcode_for_file_access(),
                 errmsg("could not close pipe to external command: %m")));
    else if (pclose_rc != 0)
    {
        ereport(ERROR,
                (errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
                 errmsg("program \"%s\" failed",
                        cstate->filename),
                 errdetail_internal("%s", wait_result_to_str(pclose_rc))));
    }
}

copy_dest_destroy()

static void copy_dest_destroy ( DestReceiver *  self )

static

Definition at line 1287 of file copyto.c.

References pfree().

Referenced by CreateCopyDestReceiver().

{
    pfree(self);
}

copy_dest_receive()

static bool copy_dest_receive ( TupleTableSlot *  slot, DestReceiver *  self  )

static

Definition at line 1259 of file copyto.c.

References CopyOneRowTo(), DR_copy::cstate, pgstat_progress_update_param(), DR_copy::processed, and PROGRESS_COPY_TUPLES_PROCESSED.

Referenced by CreateCopyDestReceiver().

{
    DR_copy    *myState = (DR_copy *) self;
    CopyToState cstate = myState->cstate;

    /* Send the data */
    CopyOneRowTo(cstate, slot);

    /* Increment the number of processed tuples, and report the progress */
    pgstat_progress_update_param(PROGRESS_COPY_TUPLES_PROCESSED,
                                 ++myState->processed);

    return true;
}

copy_dest_shutdown()

static void copy_dest_shutdown ( DestReceiver *  self )

static

Definition at line 1278 of file copyto.c.

Referenced by CreateCopyDestReceiver().

{
    /* no-op */
}

copy_dest_startup()

static void copy_dest_startup ( DestReceiver *  self, int  operation, TupleDesc  typeinfo  )

static

Definition at line 1250 of file copyto.c.

Referenced by CreateCopyDestReceiver().

{
    /* no-op */
}

CopyAttributeOutCSV()

static void CopyAttributeOutCSV ( CopyToState  cstate, char *  string, bool  use_quote, bool  single_attr  )

static

Definition at line 1165 of file copyto.c.

References CopySendChar(), CopySendString(), CopyFormatOptions::delim, DUMPSOFAR, CopyToStateData::encoding_embeds_ascii, CopyFormatOptions::escape, CopyToStateData::file_encoding, IS_HIGHBIT_SET, CopyToStateData::need_transcoding, CopyFormatOptions::null_print, CopyToStateData::opts, pg_encoding_mblen(), pg_server_to_any(), and CopyFormatOptions::quote.

Referenced by CopyOneRowTo(), and DoCopyTo().

{
    char       *ptr;
    char       *start;
    char        c;
    char        delimc = cstate->opts.delim[0];
    char        quotec = cstate->opts.quote[0];
    char        escapec = cstate->opts.escape[0];

    /* force quoting if it matches null_print (before conversion!) */
    if (!use_quote && strcmp(string, cstate->opts.null_print) == 0)
        use_quote = true;

    if (cstate->need_transcoding)
        ptr = pg_server_to_any(string, strlen(string), cstate->file_encoding);
    else
        ptr = string;

    /*
     * Make a preliminary pass to discover if it needs quoting
     */
    if (!use_quote)
    {
        /*
         * Because '\.' can be a data value, quote it if it appears alone on a
         * line so it is not interpreted as the end-of-data marker.
         */
        if (single_attr && strcmp(ptr, "\\.") == 0)
            use_quote = true;
        else
        {
            char       *tptr = ptr;

            while ((c = *tptr) != '\0')
            {
                if (c == delimc || c == quotec || c == '\n' || c == '\r')
                {
                    use_quote = true;
                    break;
                }
                if (IS_HIGHBIT_SET(c) && cstate->encoding_embeds_ascii)
                    tptr += pg_encoding_mblen(cstate->file_encoding, tptr);
                else
                    tptr++;
            }
        }
    }

    if (use_quote)
    {
        CopySendChar(cstate, quotec);

        /*
         * We adopt the same optimization strategy as in CopyAttributeOutText
         */
        start = ptr;
        while ((c = *ptr) != '\0')
        {
            if (c == quotec || c == escapec)
            {
                DUMPSOFAR();
                CopySendChar(cstate, escapec);
                start = ptr;    /* we include char in next run */
            }
            if (IS_HIGHBIT_SET(c) && cstate->encoding_embeds_ascii)
                ptr += pg_encoding_mblen(cstate->file_encoding, ptr);
            else
                ptr++;
        }
        DUMPSOFAR();

        CopySendChar(cstate, quotec);
    }
    else
    {
        /* If it doesn't need quoting, we can just dump it as-is */
        CopySendString(cstate, ptr);
    }
}

CopyAttributeOutText()

static void CopyAttributeOutText ( CopyToState  cstate, char *  string  )

static

Definition at line 1012 of file copyto.c.

References CopySendChar(), CopyFormatOptions::delim, DUMPSOFAR, CopyToStateData::encoding_embeds_ascii, CopyToStateData::file_encoding, IS_HIGHBIT_SET, CopyToStateData::need_transcoding, CopyToStateData::opts, pg_encoding_mblen(), and pg_server_to_any().

Referenced by CopyOneRowTo().

{
    char       *ptr;
    char       *start;
    char        c;
    char        delimc = cstate->opts.delim[0];

    if (cstate->need_transcoding)
        ptr = pg_server_to_any(string, strlen(string), cstate->file_encoding);
    else
        ptr = string;

    /*
     * We have to grovel through the string searching for control characters
     * and instances of the delimiter character.  In most cases, though, these
     * are infrequent.  To avoid overhead from calling CopySendData once per
     * character, we dump out all characters between escaped characters in a
     * single call.  The loop invariant is that the data from "start" to "ptr"
     * can be sent literally, but hasn't yet been.
     *
     * We can skip pg_encoding_mblen() overhead when encoding is safe, because
     * in valid backend encodings, extra bytes of a multibyte character never
     * look like ASCII.  This loop is sufficiently performance-critical that
     * it's worth making two copies of it to get the IS_HIGHBIT_SET() test out
     * of the normal safe-encoding path.
     */
    if (cstate->encoding_embeds_ascii)
    {
        start = ptr;
        while ((c = *ptr) != '\0')
        {
            if ((unsigned char) c < (unsigned char) 0x20)
            {
                /*
                 * \r and \n must be escaped, the others are traditional. We
                 * prefer to dump these using the C-like notation, rather than
                 * a backslash and the literal character, because it makes the
                 * dump file a bit more proof against Microsoftish data
                 * mangling.
                 */
                switch (c)
                {
                    case '\b':
                        c = 'b';
                        break;
                    case '\f':
                        c = 'f';
                        break;
                    case '\n':
                        c = 'n';
                        break;
                    case '\r':
                        c = 'r';
                        break;
                    case '\t':
                        c = 't';
                        break;
                    case '\v':
                        c = 'v';
                        break;
                    default:
                        /* If it's the delimiter, must backslash it */
                        if (c == delimc)
                            break;
                        /* All ASCII control chars are length 1 */
                        ptr++;
                        continue;   /* fall to end of loop */
                }
                /* if we get here, we need to convert the control char */
                DUMPSOFAR();
                CopySendChar(cstate, '\\');
                CopySendChar(cstate, c);
                start = ++ptr;  /* do not include char in next run */
            }
            else if (c == '\\' || c == delimc)
            {
                DUMPSOFAR();
                CopySendChar(cstate, '\\');
                start = ptr++;  /* we include char in next run */
            }
            else if (IS_HIGHBIT_SET(c))
                ptr += pg_encoding_mblen(cstate->file_encoding, ptr);
            else
                ptr++;
        }
    }
    else
    {
        start = ptr;
        while ((c = *ptr) != '\0')
        {
            if ((unsigned char) c < (unsigned char) 0x20)
            {
                /*
                 * \r and \n must be escaped, the others are traditional. We
                 * prefer to dump these using the C-like notation, rather than
                 * a backslash and the literal character, because it makes the
                 * dump file a bit more proof against Microsoftish data
                 * mangling.
                 */
                switch (c)
                {
                    case '\b':
                        c = 'b';
                        break;
                    case '\f':
                        c = 'f';
                        break;
                    case '\n':
                        c = 'n';
                        break;
                    case '\r':
                        c = 'r';
                        break;
                    case '\t':
                        c = 't';
                        break;
                    case '\v':
                        c = 'v';
                        break;
                    default:
                        /* If it's the delimiter, must backslash it */
                        if (c == delimc)
                            break;
                        /* All ASCII control chars are length 1 */
                        ptr++;
                        continue;   /* fall to end of loop */
                }
                /* if we get here, we need to convert the control char */
                DUMPSOFAR();
                CopySendChar(cstate, '\\');
                CopySendChar(cstate, c);
                start = ++ptr;  /* do not include char in next run */
            }
            else if (c == '\\' || c == delimc)
            {
                DUMPSOFAR();
                CopySendChar(cstate, '\\');
                start = ptr++;  /* we include char in next run */
            }
            else
                ptr++;
        }
    }

    DUMPSOFAR();
}

CopyOneRowTo()

static void CopyOneRowTo ( CopyToState  cstate, TupleTableSlot *  slot  )

static

Definition at line 931 of file copyto.c.

References attnum, CopyToStateData::attnumlist, CopyFormatOptions::binary, CopyAttributeOutCSV(), CopyAttributeOutText(), CopySendChar(), CopySendData(), CopySendEndOfRow(), CopySendInt16(), CopySendInt32(), CopySendString(), CopyFormatOptions::csv_mode, cur, CopyFormatOptions::delim, CopyFormatOptions::force_quote_flags, lfirst_int, list_length(), MemoryContextReset(), MemoryContextSwitchTo(), CopyFormatOptions::null_print_client, CopyToStateData::opts, CopyToStateData::out_functions, OutputFunctionCall(), CopyToStateData::rowcontext, SendFunctionCall(), slot_getallattrs(), TupleTableSlot::tts_isnull, TupleTableSlot::tts_values, value, VARDATA, VARHDRSZ, and VARSIZE.

Referenced by copy_dest_receive(), and DoCopyTo().

{
    bool        need_delim = false;
    FmgrInfo   *out_functions = cstate->out_functions;
    MemoryContext oldcontext;
    ListCell   *cur;
    char       *string;

    MemoryContextReset(cstate->rowcontext);
    oldcontext = MemoryContextSwitchTo(cstate->rowcontext);

    if (cstate->opts.binary)
    {
        /* Binary per-tuple header */
        CopySendInt16(cstate, list_length(cstate->attnumlist));
    }

    /* Make sure the tuple is fully deconstructed */
    slot_getallattrs(slot);

    foreach(cur, cstate->attnumlist)
    {
        int         attnum = lfirst_int(cur);
        Datum       value = slot->tts_values[attnum - 1];
        bool        isnull = slot->tts_isnull[attnum - 1];

        if (!cstate->opts.binary)
        {
            if (need_delim)
                CopySendChar(cstate, cstate->opts.delim[0]);
            need_delim = true;
        }

        if (isnull)
        {
            if (!cstate->opts.binary)
                CopySendString(cstate, cstate->opts.null_print_client);
            else
                CopySendInt32(cstate, -1);
        }
        else
        {
            if (!cstate->opts.binary)
            {
                string = OutputFunctionCall(&out_functions[attnum - 1],
                                            value);
                if (cstate->opts.csv_mode)
                    CopyAttributeOutCSV(cstate, string,
                                        cstate->opts.force_quote_flags[attnum - 1],
                                        list_length(cstate->attnumlist) == 1);
                else
                    CopyAttributeOutText(cstate, string);
            }
            else
            {
                bytea      *outputbytes;

                outputbytes = SendFunctionCall(&out_functions[attnum - 1],
                                               value);
                CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ);
                CopySendData(cstate, VARDATA(outputbytes),
                             VARSIZE(outputbytes) - VARHDRSZ);
            }
        }
    }

    CopySendEndOfRow(cstate);

    MemoryContextSwitchTo(oldcontext);
}

CopySendChar()

static void CopySendChar ( CopyToState  cstate, char  c  )

static

Definition at line 187 of file copyto.c.

References appendStringInfoCharMacro, and CopyToStateData::fe_msgbuf.

Referenced by CopyAttributeOutCSV(), CopyAttributeOutText(), CopyOneRowTo(), CopySendEndOfRow(), and DoCopyTo().

{
    appendStringInfoCharMacro(cstate->fe_msgbuf, c);
}

CopySendData()

static void CopySendData ( CopyToState  cstate, const void *  databuf, int  datasize  )

static

Definition at line 175 of file copyto.c.

References appendBinaryStringInfo(), and CopyToStateData::fe_msgbuf.

Referenced by CopyOneRowTo(), CopySendInt16(), CopySendInt32(), and DoCopyTo().

{
    appendBinaryStringInfo(cstate->fe_msgbuf, databuf, datasize);
}

CopySendEndOfRow()

static void CopySendEndOfRow ( CopyToState  cstate )

static

Definition at line 193 of file copyto.c.

References CopyFormatOptions::binary, CopyToStateData::bytes_processed, ClosePipeToProgram(), CopyToStateData::copy_dest, COPY_FILE, CopyToStateData::copy_file, COPY_FRONTEND, CopySendChar(), CopySendString(), StringInfoData::data, ereport, errcode_for_file_access(), errmsg(), ERROR, CopyToStateData::fe_msgbuf, CopyToStateData::is_program, StringInfoData::len, CopyToStateData::opts, pgstat_progress_update_param(), pq_putmessage, PROGRESS_COPY_BYTES_PROCESSED, and resetStringInfo().

Referenced by CopyOneRowTo(), and DoCopyTo().

{
    StringInfo  fe_msgbuf = cstate->fe_msgbuf;

    switch (cstate->copy_dest)
    {
        case COPY_FILE:
            if (!cstate->opts.binary)
            {
                /* Default line termination depends on platform */
#ifndef WIN32
                CopySendChar(cstate, '\n');
#else
                CopySendString(cstate, "\r\n");
#endif
            }

            if (fwrite(fe_msgbuf->data, fe_msgbuf->len, 1,
                       cstate->copy_file) != 1 ||
                ferror(cstate->copy_file))
            {
                if (cstate->is_program)
                {
                    if (errno == EPIPE)
                    {
                        /*
                         * The pipe will be closed automatically on error at
                         * the end of transaction, but we might get a better
                         * error message from the subprocess' exit code than
                         * just "Broken Pipe"
                         */
                        ClosePipeToProgram(cstate);

                        /*
                         * If ClosePipeToProgram() didn't throw an error, the
                         * program terminated normally, but closed the pipe
                         * first. Restore errno, and throw an error.
                         */
                        errno = EPIPE;
                    }
                    ereport(ERROR,
                            (errcode_for_file_access(),
                             errmsg("could not write to COPY program: %m")));
                }
                else
                    ereport(ERROR,
                            (errcode_for_file_access(),
                             errmsg("could not write to COPY file: %m")));
            }
            break;
        case COPY_FRONTEND:
            /* The FE/BE protocol uses \n as newline for all platforms */
            if (!cstate->opts.binary)
                CopySendChar(cstate, '\n');

            /* Dump the accumulated row as one CopyData message */
            (void) pq_putmessage('d', fe_msgbuf->data, fe_msgbuf->len);
            break;
    }

    /* Update the progress */
    cstate->bytes_processed += fe_msgbuf->len;
    pgstat_progress_update_param(PROGRESS_COPY_BYTES_PROCESSED, cstate->bytes_processed);

    resetStringInfo(fe_msgbuf);
}

CopySendInt16()

static void CopySendInt16 ( CopyToState  cstate, int16  val  )

inlinestatic

Definition at line 280 of file copyto.c.

References buf, CopySendData(), and pg_hton16.

Referenced by CopyOneRowTo(), and DoCopyTo().

{
    uint16      buf;

    buf = pg_hton16((uint16) val);
    CopySendData(cstate, &buf, sizeof(buf));
}

CopySendInt32()

static void CopySendInt32 ( CopyToState  cstate, int32  val  )

inlinestatic

Definition at line 268 of file copyto.c.

References buf, CopySendData(), and pg_hton32.

Referenced by CopyOneRowTo(), and DoCopyTo().

{
    uint32      buf;

    buf = pg_hton32((uint32) val);
    CopySendData(cstate, &buf, sizeof(buf));
}

CopySendString()

static void CopySendString ( CopyToState  cstate, const char *  str  )

static

Definition at line 181 of file copyto.c.

References appendBinaryStringInfo(), and CopyToStateData::fe_msgbuf.

Referenced by CopyAttributeOutCSV(), CopyOneRowTo(), and CopySendEndOfRow().

{
    appendBinaryStringInfo(cstate->fe_msgbuf, str, strlen(str));
}

CreateCopyDestReceiver()

DestReceiver* CreateCopyDestReceiver

(

void

)

Definition at line 1296 of file copyto.c.

References copy_dest_destroy(), copy_dest_receive(), copy_dest_shutdown(), copy_dest_startup(), DestCopyOut, and palloc().

Referenced by CreateDestReceiver().

{
    DR_copy    *self = (DR_copy *) palloc(sizeof(DR_copy));

    self->pub.receiveSlot = copy_dest_receive;
    self->pub.rStartup = copy_dest_startup;
    self->pub.rShutdown = copy_dest_shutdown;
    self->pub.rDestroy = copy_dest_destroy;
    self->pub.mydest = DestCopyOut;

    self->cstate = NULL;        /* will be set later */
    self->processed = 0;

    return (DestReceiver *) self;
}

DoCopyTo()

uint64 DoCopyTo

(

CopyToState

cstate

)

Definition at line 773 of file copyto.c.

References ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, attname, attnum, CopyToStateData::attnumlist, CopyFormatOptions::binary, BinarySignature, CHECK_FOR_INTERRUPTS, CopyAttributeOutCSV(), CopyOneRowTo(), CopySendChar(), CopySendData(), CopySendEndOfRow(), CopySendInt16(), CopySendInt32(), cur, CurrentMemoryContext, CopyFormatOptions::delim, QueryDesc::dest, DestRemote, ExecDropSingleTupleTableSlot(), ExecutorRun(), CopyToStateData::fe_msgbuf, CopyToStateData::file_encoding, CopyToStateData::filename, fmgr_info(), ForwardScanDirection, GetActiveSnapshot(), getTypeBinaryOutputInfo(), getTypeOutputInfo(), CopyFormatOptions::header_line, lfirst_int, list_length(), makeStringInfo(), MemoryContextDelete(), NameStr, TupleDescData::natts, CopyToStateData::need_transcoding, CopyFormatOptions::null_print, CopyFormatOptions::null_print_client, CopyFormatOptions::null_print_len, CopyToStateData::opts, CopyToStateData::out_functions, palloc(), pg_server_to_any(), pgstat_progress_update_param(), PROGRESS_COPY_TUPLES_PROCESSED, CopyToStateData::queryDesc, CopyToStateData::rel, RelationGetDescr, CopyToStateData::rowcontext, SendCopyBegin(), SendCopyEnd(), slot_getallattrs(), table_beginscan(), table_endscan(), table_scan_getnextslot(), table_slot_create(), QueryDesc::tupDesc, TupleDescAttr, and whereToSendOutput.

Referenced by DoCopy().

{
    bool        pipe = (cstate->filename == NULL);
    bool        fe_copy = (pipe && whereToSendOutput == DestRemote);
    TupleDesc   tupDesc;
    int         num_phys_attrs;
    ListCell   *cur;
    uint64      processed;

    if (fe_copy)
        SendCopyBegin(cstate);

    if (cstate->rel)
        tupDesc = RelationGetDescr(cstate->rel);
    else
        tupDesc = cstate->queryDesc->tupDesc;
    num_phys_attrs = tupDesc->natts;
    cstate->opts.null_print_client = cstate->opts.null_print;   /* default */

    /* We use fe_msgbuf as a per-row buffer regardless of copy_dest */
    cstate->fe_msgbuf = makeStringInfo();

    /* Get info about the columns we need to process. */
    cstate->out_functions = (FmgrInfo *) palloc(num_phys_attrs * sizeof(FmgrInfo));
    foreach(cur, cstate->attnumlist)
    {
        int         attnum = lfirst_int(cur);
        Oid         out_func_oid;
        bool        isvarlena;
        Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);

        if (cstate->opts.binary)
            getTypeBinaryOutputInfo(attr->atttypid,
                                    &out_func_oid,
                                    &isvarlena);
        else
            getTypeOutputInfo(attr->atttypid,
                              &out_func_oid,
                              &isvarlena);
        fmgr_info(out_func_oid, &cstate->out_functions[attnum - 1]);
    }

    /*
     * Create a temporary memory context that we can reset once per row to
     * recover palloc'd memory.  This avoids any problems with leaks inside
     * datatype output routines, and should be faster than retail pfree's
     * anyway.  (We don't need a whole econtext as CopyFrom does.)
     */
    cstate->rowcontext = AllocSetContextCreate(CurrentMemoryContext,
                                               "COPY TO",
                                               ALLOCSET_DEFAULT_SIZES);

    if (cstate->opts.binary)
    {
        /* Generate header for a binary copy */
        int32       tmp;

        /* Signature */
        CopySendData(cstate, BinarySignature, 11);
        /* Flags field */
        tmp = 0;
        CopySendInt32(cstate, tmp);
        /* No header extension */
        tmp = 0;
        CopySendInt32(cstate, tmp);
    }
    else
    {
        /*
         * For non-binary copy, we need to convert null_print to file
         * encoding, because it will be sent directly with CopySendString.
         */
        if (cstate->need_transcoding)
            cstate->opts.null_print_client = pg_server_to_any(cstate->opts.null_print,
                                                              cstate->opts.null_print_len,
                                                              cstate->file_encoding);

        /* if a header has been requested send the line */
        if (cstate->opts.header_line)
        {
            bool        hdr_delim = false;

            foreach(cur, cstate->attnumlist)
            {
                int         attnum = lfirst_int(cur);
                char       *colname;

                if (hdr_delim)
                    CopySendChar(cstate, cstate->opts.delim[0]);
                hdr_delim = true;

                colname = NameStr(TupleDescAttr(tupDesc, attnum - 1)->attname);

                CopyAttributeOutCSV(cstate, colname, false,
                                    list_length(cstate->attnumlist) == 1);
            }

            CopySendEndOfRow(cstate);
        }
    }

    if (cstate->rel)
    {
        TupleTableSlot *slot;
        TableScanDesc scandesc;

        scandesc = table_beginscan(cstate->rel, GetActiveSnapshot(), 0, NULL);
        slot = table_slot_create(cstate->rel, NULL);

        processed = 0;
        while (table_scan_getnextslot(scandesc, ForwardScanDirection, slot))
        {
            CHECK_FOR_INTERRUPTS();

            /* Deconstruct the tuple ... */
            slot_getallattrs(slot);

            /* Format and send the data */
            CopyOneRowTo(cstate, slot);

            /*
             * Increment the number of processed tuples, and report the
             * progress.
             */
            pgstat_progress_update_param(PROGRESS_COPY_TUPLES_PROCESSED,
                                         ++processed);
        }

        ExecDropSingleTupleTableSlot(slot);
        table_endscan(scandesc);
    }
    else
    {
        /* run the plan --- the dest receiver will send tuples */
        ExecutorRun(cstate->queryDesc, ForwardScanDirection, 0L, true);
        processed = ((DR_copy *) cstate->queryDesc->dest)->processed;
    }

    if (cstate->opts.binary)
    {
        /* Generate trailer for a binary copy */
        CopySendInt16(cstate, -1);
        /* Need to flush out the trailer */
        CopySendEndOfRow(cstate);
    }

    MemoryContextDelete(cstate->rowcontext);

    if (fe_copy)
        SendCopyEnd(cstate);

    return processed;
}

EndCopy()

static void EndCopy ( CopyToState  cstate )

static

Definition at line 317 of file copyto.c.

References ClosePipeToProgram(), CopyToStateData::copy_file, CopyToStateData::copycontext, ereport, errcode_for_file_access(), errmsg(), ERROR, CopyToStateData::filename, FreeFile(), CopyToStateData::is_program, MemoryContextDelete(), pfree(), and pgstat_progress_end_command().

Referenced by EndCopyTo().

{
    if (cstate->is_program)
    {
        ClosePipeToProgram(cstate);
    }
    else
    {
        if (cstate->filename != NULL && FreeFile(cstate->copy_file))
            ereport(ERROR,
                    (errcode_for_file_access(),
                     errmsg("could not close file \"%s\": %m",
                            cstate->filename)));
    }

    pgstat_progress_end_command();

    MemoryContextDelete(cstate->copycontext);
    pfree(cstate);
}

EndCopyTo()

void EndCopyTo

(

CopyToState

cstate

)

Definition at line 754 of file copyto.c.

References EndCopy(), ExecutorEnd(), ExecutorFinish(), FreeQueryDesc(), PopActiveSnapshot(), and CopyToStateData::queryDesc.

Referenced by DoCopy().

{
    if (cstate->queryDesc != NULL)
    {
        /* Close down the query and free resources. */
        ExecutorFinish(cstate->queryDesc);
        ExecutorEnd(cstate->queryDesc);
        FreeQueryDesc(cstate->queryDesc);
        PopActiveSnapshot();
    }

    /* Clean up storage */
    EndCopy(cstate);
}

SendCopyBegin()

static void SendCopyBegin ( CopyToState  cstate )

static

Definition at line 139 of file copyto.c.

References CopyToStateData::attnumlist, CopyFormatOptions::binary, buf, CopyToStateData::copy_dest, COPY_FRONTEND, format, i, list_length(), CopyToStateData::opts, pq_beginmessage(), pq_endmessage(), pq_sendbyte(), and pq_sendint16().

Referenced by DoCopyTo().

{
    StringInfoData buf;
    int         natts = list_length(cstate->attnumlist);
    int16       format = (cstate->opts.binary ? 1 : 0);
    int         i;

    pq_beginmessage(&buf, 'H');
    pq_sendbyte(&buf, format);  /* overall format */
    pq_sendint16(&buf, natts);
    for (i = 0; i < natts; i++)
        pq_sendint16(&buf, format); /* per-column formats */
    pq_endmessage(&buf);
    cstate->copy_dest = COPY_FRONTEND;
}

SendCopyEnd()

static void SendCopyEnd ( CopyToState  cstate )

static

Definition at line 156 of file copyto.c.

References Assert, CopyToStateData::fe_msgbuf, StringInfoData::len, and pq_putemptymessage().

Referenced by DoCopyTo().

{
    /* Shouldn't have any unsent data */
    Assert(cstate->fe_msgbuf->len == 0);
    /* Send Copy Done message */
    pq_putemptymessage('c');
}

Variable Documentation

BinarySignature

const char BinarySignature[11] = "PGCOPY\n\377\r\n\0"

static

Definition at line 112 of file copyto.c.

Referenced by DoCopyTo().