#include "postgres.h"
#include <sys/stat.h>
#include <unistd.h>
#include <time.h>
#include "access/xlog_internal.h"
#include "access/xlogbackup.h"
#include "backup/backup_manifest.h"
#include "backup/basebackup.h"
#include "backup/basebackup_sink.h"
#include "backup/basebackup_target.h"
#include "commands/defrem.h"
#include "common/compression.h"
#include "common/file_perm.h"
#include "lib/stringinfo.h"
#include "miscadmin.h"
#include "nodes/pg_list.h"
#include "pgstat.h"
#include "pgtar.h"
#include "port.h"
#include "postmaster/syslogger.h"
#include "replication/walsender.h"
#include "replication/walsender_private.h"
#include "storage/bufpage.h"
#include "storage/checksum.h"
#include "storage/dsm_impl.h"
#include "storage/fd.h"
#include "storage/ipc.h"
#include "storage/reinit.h"
#include "utils/builtins.h"
#include "utils/guc.h"
#include "utils/ps_status.h"
#include "utils/relcache.h"
#include "utils/resowner.h"
#include "utils/timestamp.h"

Include dependency graph for basebackup.c:

Data Structures
struct	basebackup_options

struct	exclude_list_item

Macros
#define	SINK_BUFFER_LENGTH Max(32768, BLCKSZ)

Functions
static int64	sendTablespace (bbsink sink, char path, char spcoid, bool sizeonly, struct backup_manifest_info manifest)

static int64	sendDir (bbsink sink, const char path, int basepathlen, bool sizeonly, List tablespaces, bool sendtblspclinks, backup_manifest_info manifest, const char *spcoid)

static bool	sendFile (bbsink sink, const char readfilename, const char tarfilename, struct stat statbuf, bool missing_ok, Oid dboid, backup_manifest_info manifest, const char spcoid)

static void	sendFileWithContent (bbsink sink, const char filename, const char content, backup_manifest_info manifest)

static int64	_tarWriteHeader (bbsink sink, const char filename, const char linktarget, struct stat statbuf, bool sizeonly)

static void	_tarWritePadding (bbsink *sink, int len)

static void	convert_link_to_directory (const char pathbuf, struct stat statbuf)

static void	perform_base_backup (basebackup_options opt, bbsink sink)

static void	parse_basebackup_options (List options, basebackup_options opt)

static int	compareWalFileNames (const ListCell a, const ListCell b)

static bool	is_checksummed_file (const char fullpath, const char filename)

static int	basebackup_read_file (int fd, char buf, size_t nbytes, off_t offset, const char filename, bool partial_read_ok)

void	SendBaseBackup (BaseBackupCmd *cmd)

Variables
static bool	backup_started_in_recovery = false

static long long int	total_checksum_failures

static bool	noverify_checksums = false

static const char *const	excludeDirContents []

static const struct exclude_list_item	excludeFiles []

static const struct exclude_list_item	noChecksumFiles []

Macro Definition Documentation

◆ SINK_BUFFER_LENGTH

#define SINK_BUFFER_LENGTH Max(32768, BLCKSZ)

Definition at line 58 of file basebackup.c.

Function Documentation

◆ _tarWriteHeader()

static int64 _tarWriteHeader	(	bbsink *	sink,
		const char *	filename,
		const char *	linktarget,
		struct stat *	statbuf,
		bool	sizeonly
	)

static

Definition at line 1738 of file basebackup.c.

 {
     enum tarError rc;
  
     if (!sizeonly)
     {
         /*
          * As of this writing, the smallest supported block size is 1kB, which
          * is twice TAR_BLOCK_SIZE. Since the buffer size is required to be a
          * multiple of BLCKSZ, it should be safe to assume that the buffer is
          * large enough to fit an entire tar block. We double-check by means
          * of these assertions.
          */
         StaticAssertDecl(TAR_BLOCK_SIZE <= BLCKSZ,
                          "BLCKSZ too small for tar block");
         Assert(sink->bbs_buffer_length >= TAR_BLOCK_SIZE);
  
         rc = tarCreateHeader(sink->bbs_buffer, filename, linktarget,
                              statbuf->st_size, statbuf->st_mode,
                              statbuf->st_uid, statbuf->st_gid,
                              statbuf->st_mtime);
  
         switch (rc)
         {
             case TAR_OK:
                 break;
             case TAR_NAME_TOO_LONG:
                 ereport(ERROR,
                         (errmsg("file name too long for tar format: \"%s\"",
                                 filename)));
                 break;
             case TAR_SYMLINK_TOO_LONG:
                 ereport(ERROR,
                         (errmsg("symbolic link target too long for tar format: "
                                 "file name \"%s\", target \"%s\"",
                                 filename, linktarget)));
                 break;
             default:
                 elog(ERROR, "unrecognized tar error: %d", rc);
         }
  
         bbsink_archive_contents(sink, TAR_BLOCK_SIZE);
     }
  
     return TAR_BLOCK_SIZE;
 }

References Assert(), bbsink::bbs_buffer, bbsink::bbs_buffer_length, bbsink_archive_contents(), elog(), ereport, errmsg(), ERROR, filename, stat::st_gid, stat::st_mode, stat::st_mtime, stat::st_size, stat::st_uid, StaticAssertDecl, TAR_BLOCK_SIZE, TAR_NAME_TOO_LONG, TAR_OK, TAR_SYMLINK_TOO_LONG, and tarCreateHeader().

Referenced by perform_base_backup(), sendDir(), sendFile(), sendFileWithContent(), and sendTablespace().

◆ _tarWritePadding()

static void _tarWritePadding	(	bbsink *	sink,
		int	len
	)

static

Definition at line 1790 of file basebackup.c.

 {
     int         pad = tarPaddingBytesRequired(len);
  
     /*
      * As in _tarWriteHeader, it should be safe to assume that the buffer is
      * large enough that we don't need to do this in multiple chunks.
      */
     Assert(sink->bbs_buffer_length >= TAR_BLOCK_SIZE);
     Assert(pad <= TAR_BLOCK_SIZE);
  
     if (pad > 0)
     {
         MemSet(sink->bbs_buffer, 0, pad);
         bbsink_archive_contents(sink, pad);
     }
 }

References Assert(), bbsink::bbs_buffer, bbsink::bbs_buffer_length, bbsink_archive_contents(), len, MemSet, TAR_BLOCK_SIZE, and tarPaddingBytesRequired().

Referenced by sendFile(), and sendFileWithContent().

◆ basebackup_read_file()

static int basebackup_read_file	(	int	fd,
		char *	buf,
		size_t	nbytes,
		off_t	offset,
		const char *	filename,
		bool	partial_read_ok
	)

static

Definition at line 1830 of file basebackup.c.

 {
     int         rc;
  
     pgstat_report_wait_start(WAIT_EVENT_BASEBACKUP_READ);
     rc = pg_pread(fd, buf, nbytes, offset);
     pgstat_report_wait_end();
  
     if (rc < 0)
         ereport(ERROR,
                 (errcode_for_file_access(),
                  errmsg("could not read file \"%s\": %m", filename)));
     if (!partial_read_ok && rc > 0 && rc != nbytes)
         ereport(ERROR,
                 (errcode_for_file_access(),
                  errmsg("could not read file \"%s\": read %d of %zu",
                         filename, rc, nbytes)));
  
     return rc;
 }

References buf, ereport, errcode_for_file_access(), errmsg(), ERROR, fd(), filename, pg_pread, pgstat_report_wait_end(), pgstat_report_wait_start(), and WAIT_EVENT_BASEBACKUP_READ.

Referenced by perform_base_backup(), and sendFile().

◆ compareWalFileNames()

static int compareWalFileNames	(	const ListCell *	a,
		const ListCell *	b
	)

static

Definition at line 674 of file basebackup.c.

 {
     char       *fna = (char *) lfirst(a);
     char       *fnb = (char *) lfirst(b);
  
     return strcmp(fna + 8, fnb + 8);
 }

References a, b, and lfirst.

Referenced by perform_base_backup().

◆ convert_link_to_directory()

static void convert_link_to_directory	(	const char *	pathbuf,
		struct stat *	statbuf
	)

static

Definition at line 1813 of file basebackup.c.

 {
     /* If symlink, write it as a directory anyway */
     if (S_ISLNK(statbuf->st_mode))
         statbuf->st_mode = S_IFDIR | pg_dir_create_mode;
 }

References pg_dir_create_mode, S_ISLNK, and stat::st_mode.

Referenced by sendDir().

◆ is_checksummed_file()

static bool is_checksummed_file	(	const char *	fullpath,
		const char *	filename
	)

static

Definition at line 1443 of file basebackup.c.

 {
     /* Check that the file is in a tablespace */
     if (strncmp(fullpath, "./global/", 9) == 0 ||
         strncmp(fullpath, "./base/", 7) == 0 ||
         strncmp(fullpath, "/", 1) == 0)
     {
         int         excludeIdx;
  
         /* Compare file against noChecksumFiles skip list */
         for (excludeIdx = 0; noChecksumFiles[excludeIdx].name != NULL; excludeIdx++)
         {
             int         cmplen = strlen(noChecksumFiles[excludeIdx].name);
  
             if (!noChecksumFiles[excludeIdx].match_prefix)
                 cmplen++;
             if (strncmp(filename, noChecksumFiles[excludeIdx].name,
                         cmplen) == 0)
                 return false;
         }
  
         return true;
     }
     else
         return false;
 }

References filename, exclude_list_item::name, name, and noChecksumFiles.

Referenced by sendFile().

◆ parse_basebackup_options()

static void parse_basebackup_options	(	List *	options,
		basebackup_options *	opt
	)

static

Definition at line 686 of file basebackup.c.

 {
     ListCell   *lopt;
     bool        o_label = false;
     bool        o_progress = false;
     bool        o_checkpoint = false;
     bool        o_nowait = false;
     bool        o_wal = false;
     bool        o_maxrate = false;
     bool        o_tablespace_map = false;
     bool        o_noverify_checksums = false;
     bool        o_manifest = false;
     bool        o_manifest_checksums = false;
     bool        o_target = false;
     bool        o_target_detail = false;
     char       *target_str = NULL;
     char       *target_detail_str = NULL;
     bool        o_compression = false;
     bool        o_compression_detail = false;
     char       *compression_detail_str = NULL;
  
     MemSet(opt, 0, sizeof(*opt));
     opt->manifest = MANIFEST_OPTION_NO;
     opt->manifest_checksum_type = CHECKSUM_TYPE_CRC32C;
     opt->compression = PG_COMPRESSION_NONE;
     opt->compression_specification.algorithm = PG_COMPRESSION_NONE;
  
     foreach(lopt, options)
     {
         DefElem    *defel = (DefElem *) lfirst(lopt);
  
         if (strcmp(defel->defname, "label") == 0)
         {
             if (o_label)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             opt->label = defGetString(defel);
             o_label = true;
         }
         else if (strcmp(defel->defname, "progress") == 0)
         {
             if (o_progress)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             opt->progress = defGetBoolean(defel);
             o_progress = true;
         }
         else if (strcmp(defel->defname, "checkpoint") == 0)
         {
             char       *optval = defGetString(defel);
  
             if (o_checkpoint)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             if (pg_strcasecmp(optval, "fast") == 0)
                 opt->fastcheckpoint = true;
             else if (pg_strcasecmp(optval, "spread") == 0)
                 opt->fastcheckpoint = false;
             else
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("unrecognized checkpoint type: \"%s\"",
                                 optval)));
             o_checkpoint = true;
         }
         else if (strcmp(defel->defname, "wait") == 0)
         {
             if (o_nowait)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             opt->nowait = !defGetBoolean(defel);
             o_nowait = true;
         }
         else if (strcmp(defel->defname, "wal") == 0)
         {
             if (o_wal)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             opt->includewal = defGetBoolean(defel);
             o_wal = true;
         }
         else if (strcmp(defel->defname, "max_rate") == 0)
         {
             int64       maxrate;
  
             if (o_maxrate)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
  
             maxrate = defGetInt64(defel);
             if (maxrate < MAX_RATE_LOWER || maxrate > MAX_RATE_UPPER)
                 ereport(ERROR,
                         (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
                          errmsg("%d is outside the valid range for parameter \"%s\" (%d .. %d)",
                                 (int) maxrate, "MAX_RATE", MAX_RATE_LOWER, MAX_RATE_UPPER)));
  
             opt->maxrate = (uint32) maxrate;
             o_maxrate = true;
         }
         else if (strcmp(defel->defname, "tablespace_map") == 0)
         {
             if (o_tablespace_map)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             opt->sendtblspcmapfile = defGetBoolean(defel);
             o_tablespace_map = true;
         }
         else if (strcmp(defel->defname, "verify_checksums") == 0)
         {
             if (o_noverify_checksums)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             noverify_checksums = !defGetBoolean(defel);
             o_noverify_checksums = true;
         }
         else if (strcmp(defel->defname, "manifest") == 0)
         {
             char       *optval = defGetString(defel);
             bool        manifest_bool;
  
             if (o_manifest)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             if (parse_bool(optval, &manifest_bool))
             {
                 if (manifest_bool)
                     opt->manifest = MANIFEST_OPTION_YES;
                 else
                     opt->manifest = MANIFEST_OPTION_NO;
             }
             else if (pg_strcasecmp(optval, "force-encode") == 0)
                 opt->manifest = MANIFEST_OPTION_FORCE_ENCODE;
             else
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("unrecognized manifest option: \"%s\"",
                                 optval)));
             o_manifest = true;
         }
         else if (strcmp(defel->defname, "manifest_checksums") == 0)
         {
             char       *optval = defGetString(defel);
  
             if (o_manifest_checksums)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             if (!pg_checksum_parse_type(optval,
                                         &opt->manifest_checksum_type))
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("unrecognized checksum algorithm: \"%s\"",
                                 optval)));
             o_manifest_checksums = true;
         }
         else if (strcmp(defel->defname, "target") == 0)
         {
             if (o_target)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             target_str = defGetString(defel);
             o_target = true;
         }
         else if (strcmp(defel->defname, "target_detail") == 0)
         {
             char       *optval = defGetString(defel);
  
             if (o_target_detail)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             target_detail_str = optval;
             o_target_detail = true;
         }
         else if (strcmp(defel->defname, "compression") == 0)
         {
             char       *optval = defGetString(defel);
  
             if (o_compression)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             if (!parse_compress_algorithm(optval, &opt->compression))
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("unrecognized compression algorithm: \"%s\"",
                                 optval)));
             o_compression = true;
         }
         else if (strcmp(defel->defname, "compression_detail") == 0)
         {
             if (o_compression_detail)
                 ereport(ERROR,
                         (errcode(ERRCODE_SYNTAX_ERROR),
                          errmsg("duplicate option \"%s\"", defel->defname)));
             compression_detail_str = defGetString(defel);
             o_compression_detail = true;
         }
         else
             ereport(ERROR,
                     (errcode(ERRCODE_SYNTAX_ERROR),
                      errmsg("unrecognized base backup option: \"%s\"",
                             defel->defname)));
     }
  
     if (opt->label == NULL)
         opt->label = "base backup";
     if (opt->manifest == MANIFEST_OPTION_NO)
     {
         if (o_manifest_checksums)
             ereport(ERROR,
                     (errcode(ERRCODE_SYNTAX_ERROR),
                      errmsg("manifest checksums require a backup manifest")));
         opt->manifest_checksum_type = CHECKSUM_TYPE_NONE;
     }
  
     if (target_str == NULL)
     {
         if (target_detail_str != NULL)
             ereport(ERROR,
                     (errcode(ERRCODE_SYNTAX_ERROR),
                      errmsg("target detail cannot be used without target")));
         opt->use_copytblspc = true;
         opt->send_to_client = true;
     }
     else if (strcmp(target_str, "client") == 0)
     {
         if (target_detail_str != NULL)
             ereport(ERROR,
                     (errcode(ERRCODE_SYNTAX_ERROR),
                      errmsg("target \"%s\" does not accept a target detail",
                             target_str)));
         opt->send_to_client = true;
     }
     else
         opt->target_handle =
             BaseBackupGetTargetHandle(target_str, target_detail_str);
  
     if (o_compression_detail && !o_compression)
         ereport(ERROR,
                 (errcode(ERRCODE_SYNTAX_ERROR),
                  errmsg("compression detail cannot be specified unless compression is enabled")));
  
     if (o_compression)
     {
         char       *error_detail;
  
         parse_compress_specification(opt->compression, compression_detail_str,
                                      &opt->compression_specification);
         error_detail =
             validate_compress_specification(&opt->compression_specification);
         if (error_detail != NULL)
             ereport(ERROR,
                     errcode(ERRCODE_SYNTAX_ERROR),
                     errmsg("invalid compression specification: %s",
                            error_detail));
     }
 }

Referenced by SendBaseBackup().

◆ perform_base_backup()

static void perform_base_backup	(	basebackup_options *	opt,
		bbsink *	sink
	)

static

Definition at line 230 of file basebackup.c.

 {
     bbsink_state state;
     XLogRecPtr  endptr;
     TimeLineID  endtli;
     backup_manifest_info manifest;
     BackupState *backup_state;
     StringInfo  tablespace_map;
  
     /* Initial backup state, insofar as we know it now. */
     state.tablespaces = NIL;
     state.tablespace_num = 0;
     state.bytes_done = 0;
     state.bytes_total = 0;
     state.bytes_total_is_valid = false;
  
     /* we're going to use a BufFile, so we need a ResourceOwner */
     Assert(CurrentResourceOwner == NULL);
     CurrentResourceOwner = ResourceOwnerCreate(NULL, "base backup");
  
     backup_started_in_recovery = RecoveryInProgress();
  
     InitializeBackupManifest(&manifest, opt->manifest,
                              opt->manifest_checksum_type);
  
     total_checksum_failures = 0;
  
     /* Allocate backup related varilables. */
     backup_state = (BackupState *) palloc0(sizeof(BackupState));
     tablespace_map = makeStringInfo();
  
     basebackup_progress_wait_checkpoint();
     do_pg_backup_start(opt->label, opt->fastcheckpoint, &state.tablespaces,
                        backup_state, tablespace_map);
  
     state.startptr = backup_state->startpoint;
     state.starttli = backup_state->starttli;
  
     /*
      * Once do_pg_backup_start has been called, ensure that any failure causes
      * us to abort the backup so we don't "leak" a backup counter. For this
      * reason, *all* functionality between do_pg_backup_start() and the end of
      * do_pg_backup_stop() should be inside the error cleanup block!
      */
  
     PG_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, BoolGetDatum(false));
     {
         ListCell   *lc;
         tablespaceinfo *newti;
  
         /* Add a node for the base directory at the end */
         newti = palloc0(sizeof(tablespaceinfo));
         newti->size = -1;
         state.tablespaces = lappend(state.tablespaces, newti);
  
         /*
          * Calculate the total backup size by summing up the size of each
          * tablespace
          */
         if (opt->progress)
         {
             basebackup_progress_estimate_backup_size();
  
             foreach(lc, state.tablespaces)
             {
                 tablespaceinfo *tmp = (tablespaceinfo *) lfirst(lc);
  
                 if (tmp->path == NULL)
                     tmp->size = sendDir(sink, ".", 1, true, state.tablespaces,
                                         true, NULL, NULL);
                 else
                     tmp->size = sendTablespace(sink, tmp->path, tmp->oid, true,
                                                NULL);
                 state.bytes_total += tmp->size;
             }
             state.bytes_total_is_valid = true;
         }
  
         /* notify basebackup sink about start of backup */
         bbsink_begin_backup(sink, &state, SINK_BUFFER_LENGTH);
  
         /* Send off our tablespaces one by one */
         foreach(lc, state.tablespaces)
         {
             tablespaceinfo *ti = (tablespaceinfo *) lfirst(lc);
  
             if (ti->path == NULL)
             {
                 struct stat statbuf;
                 bool        sendtblspclinks = true;
                 char       *backup_label;
  
                 bbsink_begin_archive(sink, "base.tar");
  
                 /* In the main tar, include the backup_label first... */
                 backup_label = build_backup_content(backup_state, false);
                 sendFileWithContent(sink, BACKUP_LABEL_FILE,
                                     backup_label, &manifest);
                 pfree(backup_label);
  
                 /* Then the tablespace_map file, if required... */
                 if (opt->sendtblspcmapfile)
                 {
                     sendFileWithContent(sink, TABLESPACE_MAP,
                                         tablespace_map->data, &manifest);
                     sendtblspclinks = false;
                 }
  
                 /* Then the bulk of the files... */
                 sendDir(sink, ".", 1, false, state.tablespaces,
                         sendtblspclinks, &manifest, NULL);
  
                 /* ... and pg_control after everything else. */
                 if (lstat(XLOG_CONTROL_FILE, &statbuf) != 0)
                     ereport(ERROR,
                             (errcode_for_file_access(),
                              errmsg("could not stat file \"%s\": %m",
                                     XLOG_CONTROL_FILE)));
                 sendFile(sink, XLOG_CONTROL_FILE, XLOG_CONTROL_FILE, &statbuf,
                          false, InvalidOid, &manifest, NULL);
             }
             else
             {
                 char       *archive_name = psprintf("%s.tar", ti->oid);
  
                 bbsink_begin_archive(sink, archive_name);
  
                 sendTablespace(sink, ti->path, ti->oid, false, &manifest);
             }
  
             /*
              * If we're including WAL, and this is the main data directory we
              * don't treat this as the end of the tablespace. Instead, we will
              * include the xlog files below and stop afterwards. This is safe
              * since the main data directory is always sent *last*.
              */
             if (opt->includewal && ti->path == NULL)
             {
                 Assert(lnext(state.tablespaces, lc) == NULL);
             }
             else
             {
                 /* Properly terminate the tarfile. */
                 StaticAssertDecl(2 * TAR_BLOCK_SIZE <= BLCKSZ,
                                  "BLCKSZ too small for 2 tar blocks");
                 memset(sink->bbs_buffer, 0, 2 * TAR_BLOCK_SIZE);
                 bbsink_archive_contents(sink, 2 * TAR_BLOCK_SIZE);
  
                 /* OK, that's the end of the archive. */
                 bbsink_end_archive(sink);
             }
         }
  
         basebackup_progress_wait_wal_archive(&state);
         do_pg_backup_stop(backup_state, !opt->nowait);
  
         endptr = backup_state->stoppoint;
         endtli = backup_state->stoptli;
  
         /* Deallocate backup-related variables. */
         pfree(tablespace_map->data);
         pfree(tablespace_map);
         pfree(backup_state);
     }
     PG_END_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, BoolGetDatum(false));
  
  
     if (opt->includewal)
     {
         /*
          * We've left the last tar file "open", so we can now append the
          * required WAL files to it.
          */
         char        pathbuf[MAXPGPATH];
         XLogSegNo   segno;
         XLogSegNo   startsegno;
         XLogSegNo   endsegno;
         struct stat statbuf;
         List       *historyFileList = NIL;
         List       *walFileList = NIL;
         char        firstoff[MAXFNAMELEN];
         char        lastoff[MAXFNAMELEN];
         DIR        *dir;
         struct dirent *de;
         ListCell   *lc;
         TimeLineID  tli;
  
         basebackup_progress_transfer_wal();
  
         /*
          * I'd rather not worry about timelines here, so scan pg_wal and
          * include all WAL files in the range between 'startptr' and 'endptr',
          * regardless of the timeline the file is stamped with. If there are
          * some spurious WAL files belonging to timelines that don't belong in
          * this server's history, they will be included too. Normally there
          * shouldn't be such files, but if there are, there's little harm in
          * including them.
          */
         XLByteToSeg(state.startptr, startsegno, wal_segment_size);
         XLogFileName(firstoff, state.starttli, startsegno, wal_segment_size);
         XLByteToPrevSeg(endptr, endsegno, wal_segment_size);
         XLogFileName(lastoff, endtli, endsegno, wal_segment_size);
  
         dir = AllocateDir("pg_wal");
         while ((de = ReadDir(dir, "pg_wal")) != NULL)
         {
             /* Does it look like a WAL segment, and is it in the range? */
             if (IsXLogFileName(de->d_name) &&
                 strcmp(de->d_name + 8, firstoff + 8) >= 0 &&
                 strcmp(de->d_name + 8, lastoff + 8) <= 0)
             {
                 walFileList = lappend(walFileList, pstrdup(de->d_name));
             }
             /* Does it look like a timeline history file? */
             else if (IsTLHistoryFileName(de->d_name))
             {
                 historyFileList = lappend(historyFileList, pstrdup(de->d_name));
             }
         }
         FreeDir(dir);
  
         /*
          * Before we go any further, check that none of the WAL segments we
          * need were removed.
          */
         CheckXLogRemoved(startsegno, state.starttli);
  
         /*
          * Sort the WAL filenames.  We want to send the files in order from
          * oldest to newest, to reduce the chance that a file is recycled
          * before we get a chance to send it over.
          */
         list_sort(walFileList, compareWalFileNames);
  
         /*
          * There must be at least one xlog file in the pg_wal directory, since
          * we are doing backup-including-xlog.
          */
         if (walFileList == NIL)
             ereport(ERROR,
                     (errmsg("could not find any WAL files")));
  
         /*
          * Sanity check: the first and last segment should cover startptr and
          * endptr, with no gaps in between.
          */
         XLogFromFileName((char *) linitial(walFileList),
                          &tli, &segno, wal_segment_size);
         if (segno != startsegno)
         {
             char        startfname[MAXFNAMELEN];
  
             XLogFileName(startfname, state.starttli, startsegno,
                          wal_segment_size);
             ereport(ERROR,
                     (errmsg("could not find WAL file \"%s\"", startfname)));
         }
         foreach(lc, walFileList)
         {
             char       *walFileName = (char *) lfirst(lc);
             XLogSegNo   currsegno = segno;
             XLogSegNo   nextsegno = segno + 1;
  
             XLogFromFileName(walFileName, &tli, &segno, wal_segment_size);
             if (!(nextsegno == segno || currsegno == segno))
             {
                 char        nextfname[MAXFNAMELEN];
  
                 XLogFileName(nextfname, tli, nextsegno, wal_segment_size);
                 ereport(ERROR,
                         (errmsg("could not find WAL file \"%s\"", nextfname)));
             }
         }
         if (segno != endsegno)
         {
             char        endfname[MAXFNAMELEN];
  
             XLogFileName(endfname, endtli, endsegno, wal_segment_size);
             ereport(ERROR,
                     (errmsg("could not find WAL file \"%s\"", endfname)));
         }
  
         /* Ok, we have everything we need. Send the WAL files. */
         foreach(lc, walFileList)
         {
             char       *walFileName = (char *) lfirst(lc);
             int         fd;
             size_t      cnt;
             pgoff_t     len = 0;
  
             snprintf(pathbuf, MAXPGPATH, XLOGDIR "/%s", walFileName);
             XLogFromFileName(walFileName, &tli, &segno, wal_segment_size);
  
             fd = OpenTransientFile(pathbuf, O_RDONLY | PG_BINARY);
             if (fd < 0)
             {
                 int         save_errno = errno;
  
                 /*
                  * Most likely reason for this is that the file was already
                  * removed by a checkpoint, so check for that to get a better
                  * error message.
                  */
                 CheckXLogRemoved(segno, tli);
  
                 errno = save_errno;
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("could not open file \"%s\": %m", pathbuf)));
             }
  
             if (fstat(fd, &statbuf) != 0)
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("could not stat file \"%s\": %m",
                                 pathbuf)));
             if (statbuf.st_size != wal_segment_size)
             {
                 CheckXLogRemoved(segno, tli);
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("unexpected WAL file size \"%s\"", walFileName)));
             }
  
             /* send the WAL file itself */
             _tarWriteHeader(sink, pathbuf, NULL, &statbuf, false);
  
             while ((cnt = basebackup_read_file(fd, sink->bbs_buffer,
                                                Min(sink->bbs_buffer_length,
                                                    wal_segment_size - len),
                                                len, pathbuf, true)) > 0)
             {
                 CheckXLogRemoved(segno, tli);
                 bbsink_archive_contents(sink, cnt);
  
                 len += cnt;
  
                 if (len == wal_segment_size)
                     break;
             }
  
             if (len != wal_segment_size)
             {
                 CheckXLogRemoved(segno, tli);
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("unexpected WAL file size \"%s\"", walFileName)));
             }
  
             /*
              * wal_segment_size is a multiple of TAR_BLOCK_SIZE, so no need
              * for padding.
              */
             Assert(wal_segment_size % TAR_BLOCK_SIZE == 0);
  
             CloseTransientFile(fd);
  
             /*
              * Mark file as archived, otherwise files can get archived again
              * after promotion of a new node. This is in line with
              * walreceiver.c always doing an XLogArchiveForceDone() after a
              * complete segment.
              */
             StatusFilePath(pathbuf, walFileName, ".done");
             sendFileWithContent(sink, pathbuf, "", &manifest);
         }
  
         /*
          * Send timeline history files too. Only the latest timeline history
          * file is required for recovery, and even that only if there happens
          * to be a timeline switch in the first WAL segment that contains the
          * checkpoint record, or if we're taking a base backup from a standby
          * server and the target timeline changes while the backup is taken.
          * But they are small and highly useful for debugging purposes, so
          * better include them all, always.
          */
         foreach(lc, historyFileList)
         {
             char       *fname = lfirst(lc);
  
             snprintf(pathbuf, MAXPGPATH, XLOGDIR "/%s", fname);
  
             if (lstat(pathbuf, &statbuf) != 0)
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("could not stat file \"%s\": %m", pathbuf)));
  
             sendFile(sink, pathbuf, pathbuf, &statbuf, false, InvalidOid,
                      &manifest, NULL);
  
             /* unconditionally mark file as archived */
             StatusFilePath(pathbuf, fname, ".done");
             sendFileWithContent(sink, pathbuf, "", &manifest);
         }
  
         /* Properly terminate the tar file. */
         StaticAssertStmt(2 * TAR_BLOCK_SIZE <= BLCKSZ,
                          "BLCKSZ too small for 2 tar blocks");
         memset(sink->bbs_buffer, 0, 2 * TAR_BLOCK_SIZE);
         bbsink_archive_contents(sink, 2 * TAR_BLOCK_SIZE);
  
         /* OK, that's the end of the archive. */
         bbsink_end_archive(sink);
     }
  
     AddWALInfoToBackupManifest(&manifest, state.startptr, state.starttli,
                                endptr, endtli);
  
     SendBackupManifest(&manifest, sink);
  
     bbsink_end_backup(sink, endptr, endtli);
  
     if (total_checksum_failures)
     {
         if (total_checksum_failures > 1)
             ereport(WARNING,
                     (errmsg_plural("%lld total checksum verification failure",
                                    "%lld total checksum verification failures",
                                    total_checksum_failures,
                                    total_checksum_failures)));
  
         ereport(ERROR,
                 (errcode(ERRCODE_DATA_CORRUPTED),
                  errmsg("checksum verification failure during base backup")));
     }
  
     /*
      * Make sure to free the manifest before the resource owners as manifests
      * use cryptohash contexts that may depend on resource owners (like
      * OpenSSL).
      */
     FreeBackupManifest(&manifest);
  
     /* clean up the resource owner we created */
     WalSndResourceCleanup(true);
  
     basebackup_progress_done();
 }

Referenced by SendBaseBackup().

◆ SendBaseBackup()

void SendBaseBackup ( BaseBackupCmd * cmd )

Definition at line 964 of file basebackup.c.

 {
     basebackup_options opt;
     bbsink     *sink;
     SessionBackupState status = get_backup_status();
  
     if (status == SESSION_BACKUP_RUNNING)
         ereport(ERROR,
                 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                  errmsg("a backup is already in progress in this session")));
  
     parse_basebackup_options(cmd->options, &opt);
  
     WalSndSetState(WALSNDSTATE_BACKUP);
  
     if (update_process_title)
     {
         char        activitymsg[50];
  
         snprintf(activitymsg, sizeof(activitymsg), "sending backup \"%s\"",
                  opt.label);
         set_ps_display(activitymsg);
     }
  
     /*
      * If the target is specifically 'client' then set up to stream the backup
      * to the client; otherwise, it's being sent someplace else and should not
      * be sent to the client. BaseBackupGetSink has the job of setting up a
      * sink to send the backup data wherever it needs to go.
      */
     sink = bbsink_copystream_new(opt.send_to_client);
     if (opt.target_handle != NULL)
         sink = BaseBackupGetSink(opt.target_handle, sink);
  
     /* Set up network throttling, if client requested it */
     if (opt.maxrate > 0)
         sink = bbsink_throttle_new(sink, opt.maxrate);
  
     /* Set up server-side compression, if client requested it */
     if (opt.compression == PG_COMPRESSION_GZIP)
         sink = bbsink_gzip_new(sink, &opt.compression_specification);
     else if (opt.compression == PG_COMPRESSION_LZ4)
         sink = bbsink_lz4_new(sink, &opt.compression_specification);
     else if (opt.compression == PG_COMPRESSION_ZSTD)
         sink = bbsink_zstd_new(sink, &opt.compression_specification);
  
     /* Set up progress reporting. */
     sink = bbsink_progress_new(sink, opt.progress);
  
     /*
      * Perform the base backup, but make sure we clean up the bbsink even if
      * an error occurs.
      */
     PG_TRY();
     {
         perform_base_backup(&opt, sink);
     }
     PG_FINALLY();
     {
         bbsink_cleanup(sink);
     }
     PG_END_TRY();
 }

References BaseBackupGetSink(), bbsink_cleanup(), bbsink_copystream_new(), bbsink_gzip_new(), bbsink_lz4_new(), bbsink_progress_new(), bbsink_throttle_new(), bbsink_zstd_new(), basebackup_options::compression, basebackup_options::compression_specification, ereport, errcode(), errmsg(), ERROR, get_backup_status(), basebackup_options::label, basebackup_options::maxrate, BaseBackupCmd::options, parse_basebackup_options(), perform_base_backup(), PG_COMPRESSION_GZIP, PG_COMPRESSION_LZ4, PG_COMPRESSION_ZSTD, PG_END_TRY, PG_FINALLY, PG_TRY, basebackup_options::progress, basebackup_options::send_to_client, SESSION_BACKUP_RUNNING, set_ps_display(), snprintf, status(), basebackup_options::target_handle, update_process_title, WalSndSetState(), and WALSNDSTATE_BACKUP.

Referenced by exec_replication_command().

◆ sendDir()

static int64 sendDir	(	bbsink *	sink,
		const char *	path,
		int	basepathlen,
		bool	sizeonly,
		List *	tablespaces,
		bool	sendtblspclinks,
		backup_manifest_info *	manifest,
		const char *	spcoid
	)

static

Definition at line 1146 of file basebackup.c.

 {
     DIR        *dir;
     struct dirent *de;
     char        pathbuf[MAXPGPATH * 2];
     struct stat statbuf;
     int64       size = 0;
     const char *lastDir;        /* Split last dir from parent path. */
     bool        isDbDir = false;    /* Does this directory contain relations? */
  
     /*
      * Determine if the current path is a database directory that can contain
      * relations.
      *
      * Start by finding the location of the delimiter between the parent path
      * and the current path.
      */
     lastDir = last_dir_separator(path);
  
     /* Does this path look like a database path (i.e. all digits)? */
     if (lastDir != NULL &&
         strspn(lastDir + 1, "0123456789") == strlen(lastDir + 1))
     {
         /* Part of path that contains the parent directory. */
         int         parentPathLen = lastDir - path;
  
         /*
          * Mark path as a database directory if the parent path is either
          * $PGDATA/base or a tablespace version path.
          */
         if (strncmp(path, "./base", parentPathLen) == 0 ||
             (parentPathLen >= (sizeof(TABLESPACE_VERSION_DIRECTORY) - 1) &&
              strncmp(lastDir - (sizeof(TABLESPACE_VERSION_DIRECTORY) - 1),
                      TABLESPACE_VERSION_DIRECTORY,
                      sizeof(TABLESPACE_VERSION_DIRECTORY) - 1) == 0))
             isDbDir = true;
     }
  
     dir = AllocateDir(path);
     while ((de = ReadDir(dir, path)) != NULL)
     {
         int         excludeIdx;
         bool        excludeFound;
         ForkNumber  relForkNum; /* Type of fork if file is a relation */
         int         relnumchars;    /* Chars in filename that are the
                                      * relnumber */
  
         /* Skip special stuff */
         if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0)
             continue;
  
         /* Skip temporary files */
         if (strncmp(de->d_name,
                     PG_TEMP_FILE_PREFIX,
                     strlen(PG_TEMP_FILE_PREFIX)) == 0)
             continue;
  
         /*
          * Check if the postmaster has signaled us to exit, and abort with an
          * error in that case. The error handler further up will call
          * do_pg_abort_backup() for us. Also check that if the backup was
          * started while still in recovery, the server wasn't promoted.
          * do_pg_backup_stop() will check that too, but it's better to stop
          * the backup early than continue to the end and fail there.
          */
         CHECK_FOR_INTERRUPTS();
         if (RecoveryInProgress() != backup_started_in_recovery)
             ereport(ERROR,
                     (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
                      errmsg("the standby was promoted during online backup"),
                      errhint("This means that the backup being taken is corrupt "
                              "and should not be used. "
                              "Try taking another online backup.")));
  
         /* Scan for files that should be excluded */
         excludeFound = false;
         for (excludeIdx = 0; excludeFiles[excludeIdx].name != NULL; excludeIdx++)
         {
             int         cmplen = strlen(excludeFiles[excludeIdx].name);
  
             if (!excludeFiles[excludeIdx].match_prefix)
                 cmplen++;
             if (strncmp(de->d_name, excludeFiles[excludeIdx].name, cmplen) == 0)
             {
                 elog(DEBUG1, "file \"%s\" excluded from backup", de->d_name);
                 excludeFound = true;
                 break;
             }
         }
  
         if (excludeFound)
             continue;
  
         /* Exclude all forks for unlogged tables except the init fork */
         if (isDbDir &&
             parse_filename_for_nontemp_relation(de->d_name, &relnumchars,
                                                 &relForkNum))
         {
             /* Never exclude init forks */
             if (relForkNum != INIT_FORKNUM)
             {
                 char        initForkFile[MAXPGPATH];
                 char        relNumber[OIDCHARS + 1];
  
                 /*
                  * If any other type of fork, check if there is an init fork
                  * with the same RelFileNumber. If so, the file can be
                  * excluded.
                  */
                 memcpy(relNumber, de->d_name, relnumchars);
                 relNumber[relnumchars] = '\0';
                 snprintf(initForkFile, sizeof(initForkFile), "%s/%s_init",
                          path, relNumber);
  
                 if (lstat(initForkFile, &statbuf) == 0)
                 {
                     elog(DEBUG2,
                          "unlogged relation file \"%s\" excluded from backup",
                          de->d_name);
  
                     continue;
                 }
             }
         }
  
         /* Exclude temporary relations */
         if (isDbDir && looks_like_temp_rel_name(de->d_name))
         {
             elog(DEBUG2,
                  "temporary relation file \"%s\" excluded from backup",
                  de->d_name);
  
             continue;
         }
  
         snprintf(pathbuf, sizeof(pathbuf), "%s/%s", path, de->d_name);
  
         /* Skip pg_control here to back up it last */
         if (strcmp(pathbuf, "./global/pg_control") == 0)
             continue;
  
         if (lstat(pathbuf, &statbuf) != 0)
         {
             if (errno != ENOENT)
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("could not stat file or directory \"%s\": %m",
                                 pathbuf)));
  
             /* If the file went away while scanning, it's not an error. */
             continue;
         }
  
         /* Scan for directories whose contents should be excluded */
         excludeFound = false;
         for (excludeIdx = 0; excludeDirContents[excludeIdx] != NULL; excludeIdx++)
         {
             if (strcmp(de->d_name, excludeDirContents[excludeIdx]) == 0)
             {
                 elog(DEBUG1, "contents of directory \"%s\" excluded from backup", de->d_name);
                 convert_link_to_directory(pathbuf, &statbuf);
                 size += _tarWriteHeader(sink, pathbuf + basepathlen + 1, NULL,
                                         &statbuf, sizeonly);
                 excludeFound = true;
                 break;
             }
         }
  
         if (excludeFound)
             continue;
  
         /*
          * We can skip pg_wal, the WAL segments need to be fetched from the
          * WAL archive anyway. But include it as an empty directory anyway, so
          * we get permissions right.
          */
         if (strcmp(pathbuf, "./pg_wal") == 0)
         {
             /* If pg_wal is a symlink, write it as a directory anyway */
             convert_link_to_directory(pathbuf, &statbuf);
             size += _tarWriteHeader(sink, pathbuf + basepathlen + 1, NULL,
                                     &statbuf, sizeonly);
  
             /*
              * Also send archive_status directory (by hackishly reusing
              * statbuf from above ...).
              */
             size += _tarWriteHeader(sink, "./pg_wal/archive_status", NULL,
                                     &statbuf, sizeonly);
  
             continue;           /* don't recurse into pg_wal */
         }
  
         /* Allow symbolic links in pg_tblspc only */
         if (strcmp(path, "./pg_tblspc") == 0 && S_ISLNK(statbuf.st_mode))
         {
             char        linkpath[MAXPGPATH];
             int         rllen;
  
             rllen = readlink(pathbuf, linkpath, sizeof(linkpath));
             if (rllen < 0)
                 ereport(ERROR,
                         (errcode_for_file_access(),
                          errmsg("could not read symbolic link \"%s\": %m",
                                 pathbuf)));
             if (rllen >= sizeof(linkpath))
                 ereport(ERROR,
                         (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                          errmsg("symbolic link \"%s\" target is too long",
                                 pathbuf)));
             linkpath[rllen] = '\0';
  
             size += _tarWriteHeader(sink, pathbuf + basepathlen + 1, linkpath,
                                     &statbuf, sizeonly);
         }
         else if (S_ISDIR(statbuf.st_mode))
         {
             bool        skip_this_dir = false;
             ListCell   *lc;
  
             /*
              * Store a directory entry in the tar file so we can get the
              * permissions right.
              */
             size += _tarWriteHeader(sink, pathbuf + basepathlen + 1, NULL, &statbuf,
                                     sizeonly);
  
             /*
              * Call ourselves recursively for a directory, unless it happens
              * to be a separate tablespace located within PGDATA.
              */
             foreach(lc, tablespaces)
             {
                 tablespaceinfo *ti = (tablespaceinfo *) lfirst(lc);
  
                 /*
                  * ti->rpath is the tablespace relative path within PGDATA, or
                  * NULL if the tablespace has been properly located somewhere
                  * else.
                  *
                  * Skip past the leading "./" in pathbuf when comparing.
                  */
                 if (ti->rpath && strcmp(ti->rpath, pathbuf + 2) == 0)
                 {
                     skip_this_dir = true;
                     break;
                 }
             }
  
             /*
              * skip sending directories inside pg_tblspc, if not required.
              */
             if (strcmp(pathbuf, "./pg_tblspc") == 0 && !sendtblspclinks)
                 skip_this_dir = true;
  
             if (!skip_this_dir)
                 size += sendDir(sink, pathbuf, basepathlen, sizeonly, tablespaces,
                                 sendtblspclinks, manifest, spcoid);
         }
         else if (S_ISREG(statbuf.st_mode))
         {
             bool        sent = false;
  
             if (!sizeonly)
                 sent = sendFile(sink, pathbuf, pathbuf + basepathlen + 1, &statbuf,
                                 true, isDbDir ? atooid(lastDir + 1) : InvalidOid,
                                 manifest, spcoid);
  
             if (sent || sizeonly)
             {
                 /* Add size. */
                 size += statbuf.st_size;
  
                 /* Pad to a multiple of the tar block size. */
                 size += tarPaddingBytesRequired(statbuf.st_size);
  
                 /* Size of the header for the file. */
                 size += TAR_BLOCK_SIZE;
             }
         }
         else
             ereport(WARNING,
                     (errmsg("skipping special file \"%s\"", pathbuf)));
     }
     FreeDir(dir);
     return size;
 }

References _tarWriteHeader(), AllocateDir(), atooid, backup_started_in_recovery, CHECK_FOR_INTERRUPTS, convert_link_to_directory(), dirent::d_name, DEBUG1, DEBUG2, elog(), ereport, errcode(), errcode_for_file_access(), errhint(), errmsg(), ERROR, excludeDirContents, excludeFiles, FreeDir(), INIT_FORKNUM, InvalidOid, last_dir_separator(), lfirst, looks_like_temp_rel_name(), lstat, manifest, MAXPGPATH, exclude_list_item::name, name, OIDCHARS, parse_filename_for_nontemp_relation(), PG_TEMP_FILE_PREFIX, ReadDir(), readlink, RecoveryInProgress(), tablespaceinfo::rpath, S_ISDIR, S_ISLNK, S_ISREG, sendFile(), snprintf, stat::st_mode, stat::st_size, TABLESPACE_VERSION_DIRECTORY, TAR_BLOCK_SIZE, tarPaddingBytesRequired(), and WARNING.

Referenced by perform_base_backup(), and sendTablespace().

◆ sendFile()

static bool sendFile	(	bbsink *	sink,
		const char *	readfilename,
		const char *	tarfilename,
		struct stat *	statbuf,
		bool	missing_ok,
		Oid	dboid,
		backup_manifest_info *	manifest,
		const char *	spcoid
	)

static

Definition at line 1482 of file basebackup.c.

 {
     int         fd;
     BlockNumber blkno = 0;
     bool        block_retry = false;
     uint16      checksum;
     int         checksum_failures = 0;
     off_t       cnt;
     int         i;
     pgoff_t     len = 0;
     char       *page;
     PageHeader  phdr;
     int         segmentno = 0;
     char       *segmentpath;
     bool        verify_checksum = false;
     pg_checksum_context checksum_ctx;
  
     if (pg_checksum_init(&checksum_ctx, manifest->checksum_type) < 0)
         elog(ERROR, "could not initialize checksum of file \"%s\"",
              readfilename);
  
     fd = OpenTransientFile(readfilename, O_RDONLY | PG_BINARY);
     if (fd < 0)
     {
         if (errno == ENOENT && missing_ok)
             return false;
         ereport(ERROR,
                 (errcode_for_file_access(),
                  errmsg("could not open file \"%s\": %m", readfilename)));
     }
  
     _tarWriteHeader(sink, tarfilename, NULL, statbuf, false);
  
     if (!noverify_checksums && DataChecksumsEnabled())
     {
         char       *filename;
  
         /*
          * Get the filename (excluding path).  As last_dir_separator()
          * includes the last directory separator, we chop that off by
          * incrementing the pointer.
          */
         filename = last_dir_separator(readfilename) + 1;
  
         if (is_checksummed_file(readfilename, filename))
         {
             verify_checksum = true;
  
             /*
              * Cut off at the segment boundary (".") to get the segment number
              * in order to mix it into the checksum.
              */
             segmentpath = strstr(filename, ".");
             if (segmentpath != NULL)
             {
                 segmentno = atoi(segmentpath + 1);
                 if (segmentno == 0)
                     ereport(ERROR,
                             (errmsg("invalid segment number %d in file \"%s\"",
                                     segmentno, filename)));
             }
         }
     }
  
     /*
      * Loop until we read the amount of data the caller told us to expect. The
      * file could be longer, if it was extended while we were sending it, but
      * for a base backup we can ignore such extended data. It will be restored
      * from WAL.
      */
     while (len < statbuf->st_size)
     {
         size_t      remaining = statbuf->st_size - len;
  
         /* Try to read some more data. */
         cnt = basebackup_read_file(fd, sink->bbs_buffer,
                                    Min(sink->bbs_buffer_length, remaining),
                                    len, readfilename, true);
  
         /*
          * The checksums are verified at block level, so we iterate over the
          * buffer in chunks of BLCKSZ, after making sure that
          * TAR_SEND_SIZE/buf is divisible by BLCKSZ and we read a multiple of
          * BLCKSZ bytes.
          */
         Assert((sink->bbs_buffer_length % BLCKSZ) == 0);
  
         if (verify_checksum && (cnt % BLCKSZ != 0))
         {
             ereport(WARNING,
                     (errmsg("could not verify checksum in file \"%s\", block "
                             "%u: read buffer size %d and page size %d "
                             "differ",
                             readfilename, blkno, (int) cnt, BLCKSZ)));
             verify_checksum = false;
         }
  
         if (verify_checksum)
         {
             for (i = 0; i < cnt / BLCKSZ; i++)
             {
                 page = sink->bbs_buffer + BLCKSZ * i;
  
                 /*
                  * Only check pages which have not been modified since the
                  * start of the base backup. Otherwise, they might have been
                  * written only halfway and the checksum would not be valid.
                  * However, replaying WAL would reinstate the correct page in
                  * this case. We also skip completely new pages, since they
                  * don't have a checksum yet.
                  */
                 if (!PageIsNew(page) && PageGetLSN(page) < sink->bbs_state->startptr)
                 {
                     checksum = pg_checksum_page((char *) page, blkno + segmentno * RELSEG_SIZE);
                     phdr = (PageHeader) page;
                     if (phdr->pd_checksum != checksum)
                     {
                         /*
                          * Retry the block on the first failure.  It's
                          * possible that we read the first 4K page of the
                          * block just before postgres updated the entire block
                          * so it ends up looking torn to us. If, before we
                          * retry the read, the concurrent write of the block
                          * finishes, the page LSN will be updated and we'll
                          * realize that we should ignore this block.
                          *
                          * There's no guarantee that this will actually
                          * happen, though: the torn write could take an
                          * arbitrarily long time to complete. Retrying multiple
                          * times wouldn't fix this problem, either, though
                          * it would reduce the chances of it happening in
                          * practice. The only real fix here seems to be to
                          * have some kind of interlock that allows us to wait
                          * until we can be certain that no write to the block
                          * is in progress. Since we don't have any such thing
                          * right now, we just do this and hope for the best.
                          */
                         if (block_retry == false)
                         {
                             int         reread_cnt;
  
                             /* Reread the failed block */
                             reread_cnt =
                                 basebackup_read_file(fd,
                                                      sink->bbs_buffer + BLCKSZ * i,
                                                      BLCKSZ, len + BLCKSZ * i,
                                                      readfilename,
                                                      false);
                             if (reread_cnt == 0)
                             {
                                 /*
                                  * If we hit end-of-file, a concurrent
                                  * truncation must have occurred, so break out
                                  * of this loop just as if the initial fread()
                                  * returned 0. We'll drop through to the same
                                  * code that handles that case. (We must fix
                                  * up cnt first, though.)
                                  */
                                 cnt = BLCKSZ * i;
                                 break;
                             }
  
                             /* Set flag so we know a retry was attempted */
                             block_retry = true;
  
                             /* Reset loop to validate the block again */
                             i--;
                             continue;
                         }
  
                         checksum_failures++;
  
                         if (checksum_failures <= 5)
                             ereport(WARNING,
                                     (errmsg("checksum verification failed in "
                                             "file \"%s\", block %u: calculated "
                                             "%X but expected %X",
                                             readfilename, blkno, checksum,
                                             phdr->pd_checksum)));
                         if (checksum_failures == 5)
                             ereport(WARNING,
                                     (errmsg("further checksum verification "
                                             "failures in file \"%s\" will not "
                                             "be reported", readfilename)));
                     }
                 }
                 block_retry = false;
                 blkno++;
             }
         }
  
         /*
          * If we hit end-of-file, a concurrent truncation must have occurred.
          * That's not an error condition, because WAL replay will fix things
          * up.
          */
         if (cnt == 0)
             break;
  
         /* Archive the data we just read. */
         bbsink_archive_contents(sink, cnt);
  
         /* Also feed it to the checksum machinery. */
         if (pg_checksum_update(&checksum_ctx,
                                (uint8 *) sink->bbs_buffer, cnt) < 0)
             elog(ERROR, "could not update checksum of base backup");
  
         len += cnt;
     }
  
     /* If the file was truncated while we were sending it, pad it with zeros */
     while (len < statbuf->st_size)
     {
         size_t      remaining = statbuf->st_size - len;
         size_t      nbytes = Min(sink->bbs_buffer_length, remaining);
  
         MemSet(sink->bbs_buffer, 0, nbytes);
         if (pg_checksum_update(&checksum_ctx,
                                (uint8 *) sink->bbs_buffer,
                                nbytes) < 0)
             elog(ERROR, "could not update checksum of base backup");
         bbsink_archive_contents(sink, nbytes);
         len += nbytes;
     }
  
     /*
      * Pad to a block boundary, per tar format requirements. (This small piece
      * of data is probably not worth throttling, and is not checksummed
      * because it's not actually part of the file.)
      */
     _tarWritePadding(sink, len);
  
     CloseTransientFile(fd);
  
     if (checksum_failures > 1)
     {
         ereport(WARNING,
                 (errmsg_plural("file \"%s\" has a total of %d checksum verification failure",
                                "file \"%s\" has a total of %d checksum verification failures",
                                checksum_failures,
                                readfilename, checksum_failures)));
  
         pgstat_report_checksum_failures_in_db(dboid, checksum_failures);
     }
  
     total_checksum_failures += checksum_failures;
  
     AddFileToBackupManifest(manifest, spcoid, tarfilename, statbuf->st_size,
                             (pg_time_t) statbuf->st_mtime, &checksum_ctx);
  
     return true;
 }

References _tarWriteHeader(), _tarWritePadding(), AddFileToBackupManifest(), Assert(), basebackup_read_file(), bbsink::bbs_buffer, bbsink::bbs_buffer_length, bbsink::bbs_state, bbsink_archive_contents(), CloseTransientFile(), DataChecksumsEnabled(), elog(), ereport, errcode_for_file_access(), errmsg(), errmsg_plural(), ERROR, fd(), filename, i, is_checksummed_file(), last_dir_separator(), len, manifest, MemSet, Min, noverify_checksums, OpenTransientFile(), PageGetLSN(), PageIsNew(), PageHeaderData::pd_checksum, PG_BINARY, pg_checksum_init(), pg_checksum_page(), pg_checksum_update(), pgoff_t, pgstat_report_checksum_failures_in_db(), remaining, stat::st_mtime, stat::st_size, bbsink_state::startptr, total_checksum_failures, and WARNING.

Referenced by perform_base_backup(), and sendDir().

◆ sendFileWithContent()

static void sendFileWithContent	(	bbsink *	sink,
		const char *	filename,
		const char *	content,
		backup_manifest_info *	manifest
	)

static

Definition at line 1032 of file basebackup.c.

 {
     struct stat statbuf;
     int         bytes_done = 0,
                 len;
     pg_checksum_context checksum_ctx;
  
     if (pg_checksum_init(&checksum_ctx, manifest->checksum_type) < 0)
         elog(ERROR, "could not initialize checksum of file \"%s\"",
              filename);
  
     len = strlen(content);
  
     /*
      * Construct a stat struct for the backup_label file we're injecting in
      * the tar.
      */
     /* Windows doesn't have the concept of uid and gid */
 #ifdef WIN32
     statbuf.st_uid = 0;
     statbuf.st_gid = 0;
 #else
     statbuf.st_uid = geteuid();
     statbuf.st_gid = getegid();
 #endif
     statbuf.st_mtime = time(NULL);
     statbuf.st_mode = pg_file_create_mode;
     statbuf.st_size = len;
  
     _tarWriteHeader(sink, filename, NULL, &statbuf, false);
  
     if (pg_checksum_update(&checksum_ctx, (uint8 *) content, len) < 0)
         elog(ERROR, "could not update checksum of file \"%s\"",
              filename);
  
     while (bytes_done < len)
     {
         size_t      remaining = len - bytes_done;
         size_t      nbytes = Min(sink->bbs_buffer_length, remaining);
  
         memcpy(sink->bbs_buffer, content, nbytes);
         bbsink_archive_contents(sink, nbytes);
         bytes_done += nbytes;
         content += nbytes;
     }
  
     _tarWritePadding(sink, len);
  
     AddFileToBackupManifest(manifest, NULL, filename, len,
                             (pg_time_t) statbuf.st_mtime, &checksum_ctx);
 }

References _tarWriteHeader(), _tarWritePadding(), AddFileToBackupManifest(), bbsink::bbs_buffer, bbsink::bbs_buffer_length, bbsink_archive_contents(), elog(), ERROR, filename, len, manifest, Min, pg_checksum_init(), pg_checksum_update(), pg_file_create_mode, remaining, stat::st_gid, stat::st_mode, stat::st_mtime, stat::st_size, and stat::st_uid.

Referenced by perform_base_backup().

◆ sendTablespace()

static int64 sendTablespace	(	bbsink *	sink,
		char *	path,
		char *	spcoid,
		bool	sizeonly,
		struct backup_manifest_info *	manifest
	)

static

Definition at line 1093 of file basebackup.c.

 {
     int64       size;
     char        pathbuf[MAXPGPATH];
     struct stat statbuf;
  
     /*
      * 'path' points to the tablespace location, but we only want to include
      * the version directory in it that belongs to us.
      */
     snprintf(pathbuf, sizeof(pathbuf), "%s/%s", path,
              TABLESPACE_VERSION_DIRECTORY);
  
     /*
      * Store a directory entry in the tar file so we get the permissions
      * right.
      */
     if (lstat(pathbuf, &statbuf) != 0)
     {
         if (errno != ENOENT)
             ereport(ERROR,
                     (errcode_for_file_access(),
                      errmsg("could not stat file or directory \"%s\": %m",
                             pathbuf)));
  
         /* If the tablespace went away while scanning, it's no error. */
         return 0;
     }
  
     size = _tarWriteHeader(sink, TABLESPACE_VERSION_DIRECTORY, NULL, &statbuf,
                            sizeonly);
  
     /* Send all the files in the tablespace version directory */
     size += sendDir(sink, pathbuf, strlen(path), sizeonly, NIL, true, manifest,
                     spcoid);
  
     return size;
 }

References _tarWriteHeader(), ereport, errcode_for_file_access(), errmsg(), ERROR, lstat, manifest, MAXPGPATH, NIL, sendDir(), snprintf, and TABLESPACE_VERSION_DIRECTORY.

Referenced by perform_base_backup().

Variable Documentation

◆ backup_started_in_recovery

bool backup_started_in_recovery = false

static

Definition at line 102 of file basebackup.c.

Referenced by do_pg_backup_start(), perform_base_backup(), and sendDir().

◆ excludeDirContents

const char* const excludeDirContents[]

static

Initial value:

=
{
    
    PG_STAT_TMP_DIR,
 
    "pg_replslot",
 
    PG_DYNSHMEM_DIR,
 
    "pg_notify",
 
    "pg_serial",
 
    "pg_snapshots",
 
    "pg_subtrans",
 
    NULL
}

Definition at line 130 of file basebackup.c.

Referenced by sendDir().

◆ excludeFiles

const struct exclude_list_item excludeFiles[]

static

Initial value:

=
{
    
    {PG_AUTOCONF_FILENAME ".tmp", false},
 
    {LOG_METAINFO_DATAFILE_TMP, false},
 
    {RELCACHE_INIT_FILENAME, true},
 
    {BACKUP_LABEL_FILE, false},
    {TABLESPACE_MAP, false},
 
    {"backup_manifest", false},
 
    {"postmaster.pid", false},
    {"postmaster.opts", false},
 
    {NULL, false}
}

Definition at line 130 of file basebackup.c.

Referenced by sendDir().

◆ noChecksumFiles

const struct exclude_list_item noChecksumFiles[]

static

Initial value:

= {
    {"pg_control", false},
    {"pg_filenode.map", false},
    {"pg_internal.init", true},
    {"PG_VERSION", false},
 
 
 
    {NULL, false}
}

Definition at line 130 of file basebackup.c.

Referenced by is_checksummed_file().

◆ noverify_checksums

bool noverify_checksums = false

static

Definition at line 108 of file basebackup.c.

Referenced by parse_basebackup_options(), and sendFile().

◆ total_checksum_failures

long long int total_checksum_failures

static

Definition at line 105 of file basebackup.c.

Referenced by perform_base_backup(), and sendFile().

Data Structures

Macros

Functions

Variables

Macro Definition Documentation

◆ SINK_BUFFER_LENGTH

Function Documentation

◆ _tarWriteHeader()

◆ _tarWritePadding()

◆ basebackup_read_file()

◆ compareWalFileNames()

◆ convert_link_to_directory()

◆ is_checksummed_file()

◆ parse_basebackup_options()

◆ perform_base_backup()

◆ SendBaseBackup()

◆ sendDir()

◆ sendFile()

◆ sendFileWithContent()

◆ sendTablespace()

Variable Documentation

◆ backup_started_in_recovery

◆ excludeDirContents

◆ excludeFiles

◆ noChecksumFiles

◆ noverify_checksums

◆ total_checksum_failures