pg_archivecleanup.c File Reference

#include "postgres_fe.h"
#include <ctype.h>
#include <dirent.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/time.h>
#include "access/xlog_internal.h"
#include "common/logging.h"
#include "pg_getopt.h"

Include dependency graph for pg_archivecleanup.c:

Go to the source code of this file.

Functions
static void	Initialize (void)
static void	TrimExtension (char *filename, char *extension)
static void	CleanupPriorWALFiles (void)
static void	SetWALFileNameForCleanup (void)
static void	usage (void)
int	main (int argc, char **argv)

Variables
const char *	progname
bool	dryrun = false
char *	additional_ext = NULL
char *	archiveLocation
char *	restartWALFileName
char	exclusiveCleanupFileName [MAXFNAMELEN]

Function Documentation

CleanupPriorWALFiles()

static void CleanupPriorWALFiles ( void  )

static

Definition at line 89 of file pg_archivecleanup.c.

{
    int         rc;
    DIR        *xldir;
    struct dirent *xlde;
    char        walfile[MAXPGPATH];
 
    if ((xldir = opendir(archiveLocation)) != NULL)
    {
        while (errno = 0, (xlde = readdir(xldir)) != NULL)
        {
            /*
             * Truncation is essentially harmless, because we skip names of
             * length other than XLOG_FNAME_LEN.  (In principle, one could use
             * a 1000-character additional_ext and get trouble.)
             */
            strlcpy(walfile, xlde->d_name, MAXPGPATH);
            TrimExtension(walfile, additional_ext);
 
            /*
             * We ignore the timeline part of the XLOG segment identifiers in
             * deciding whether a segment is still needed.  This ensures that
             * we won't prematurely remove a segment from a parent timeline.
             * We could probably be a little more proactive about removing
             * segments of non-parent timelines, but that would be a whole lot
             * more complicated.
             *
             * We use the alphanumeric sorting property of the filenames to
             * decide which ones are earlier than the exclusiveCleanupFileName
             * file. Note that this means files are not removed in the order
             * they were originally written, in case this worries you.
             */
            if ((IsXLogFileName(walfile) || IsPartialXLogFileName(walfile)) &&
                strcmp(walfile + 8, exclusiveCleanupFileName + 8) < 0)
            {
                char        WALFilePath[MAXPGPATH * 2]; /* the file path
                                                         * including archive */
 
                /*
                 * Use the original file name again now, including any
                 * extension that might have been chopped off before testing
                 * the sequence.
                 */
                snprintf(WALFilePath, sizeof(WALFilePath), "%s/%s",
                         archiveLocation, xlde->d_name);
 
                if (dryrun)
                {
                    /*
                     * Prints the name of the file to be removed and skips the
                     * actual removal.  The regular printout is so that the
                     * user can pipe the output into some other program.
                     */
                    printf("%s\n", WALFilePath);
                    pg_log_debug("file \"%s\" would be removed", WALFilePath);
                    continue;
                }
 
                pg_log_debug("removing file \"%s\"", WALFilePath);
 
                rc = unlink(WALFilePath);
                if (rc != 0)
                    pg_fatal("could not remove file \"%s\": %m",
                             WALFilePath);
            }
        }
 
        if (errno)
            pg_fatal("could not read archive location \"%s\": %m",
                     archiveLocation);
        if (closedir(xldir))
            pg_fatal("could not close archive location \"%s\": %m",
                     archiveLocation);
    }
    else
        pg_fatal("could not open archive location \"%s\": %m",
                 archiveLocation);
}

References additional_ext, archiveLocation, closedir(), dirent::d_name, dryrun, exclusiveCleanupFileName, IsPartialXLogFileName(), IsXLogFileName(), MAXPGPATH, opendir(), pg_fatal, pg_log_debug, printf, readdir(), snprintf, strlcpy(), TrimExtension(), and walfile.

Referenced by main().

Initialize()

static void Initialize ( void  )

static

Definition at line 55 of file pg_archivecleanup.c.

{
    /*
     * This code assumes that archiveLocation is a directory, so we use stat
     * to test if it's accessible.
     */
    struct stat stat_buf;
 
    if (stat(archiveLocation, &stat_buf) != 0 ||
        !S_ISDIR(stat_buf.st_mode))
    {
        pg_log_error("archive location \"%s\" does not exist",
                     archiveLocation);
        exit(2);
    }
}

References archiveLocation, exit(), pg_log_error, S_ISDIR, stat::st_mode, and stat.

Referenced by main().

main()

int main	(	int	argc,
		char **	argv
	)

Definition at line 275 of file pg_archivecleanup.c.

{
    int         c;
 
    pg_logging_init(argv[0]);
    set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_archivecleanup"));
    progname = get_progname(argv[0]);
 
    if (argc > 1)
    {
        if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
        {
            usage();
            exit(0);
        }
        if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
        {
            puts("pg_archivecleanup (PostgreSQL) " PG_VERSION);
            exit(0);
        }
    }
 
    while ((c = getopt(argc, argv, "dnx:")) != -1)
    {
        switch (c)
        {
            case 'd':           /* Debug mode */
                pg_logging_increase_verbosity();
                break;
            case 'n':           /* Dry-Run mode */
                dryrun = true;
                break;
            case 'x':
                additional_ext = pg_strdup(optarg); /* Extension to remove
                                                     * from xlogfile names */
                break;
            default:
                /* getopt already emitted a complaint */
                pg_log_error_hint("Try \"%s --help\" for more information.", progname);
                exit(2);
        }
    }
 
    /*
     * We will go to the archiveLocation to check restartWALFileName.
     * restartWALFileName may not exist anymore, which would not be an error,
     * so we separate the archiveLocation and restartWALFileName so we can
     * check separately whether archiveLocation exists, if not that is an
     * error
     */
    if (optind < argc)
    {
        archiveLocation = argv[optind];
        optind++;
    }
    else
    {
        pg_log_error("must specify archive location");
        pg_log_error_hint("Try \"%s --help\" for more information.", progname);
        exit(2);
    }
 
    if (optind < argc)
    {
        restartWALFileName = argv[optind];
        optind++;
    }
    else
    {
        pg_log_error("must specify oldest kept WAL file");
        pg_log_error_hint("Try \"%s --help\" for more information.", progname);
        exit(2);
    }
 
    if (optind < argc)
    {
        pg_log_error("too many command-line arguments");
        pg_log_error_hint("Try \"%s --help\" for more information.", progname);
        exit(2);
    }
 
    /*
     * Check archive exists and other initialization if required.
     */
    Initialize();
 
    /*
     * Check filename is a valid name, then process to find cut-off
     */
    SetWALFileNameForCleanup();
 
    pg_log_debug("keeping WAL file \"%s/%s\" and later",
                 archiveLocation, exclusiveCleanupFileName);
 
    /*
     * Remove WAL files older than cut-off
     */
    CleanupPriorWALFiles();
 
    exit(0);
}

References additional_ext, archiveLocation, CleanupPriorWALFiles(), dryrun, exclusiveCleanupFileName, exit(), get_progname(), getopt(), Initialize(), optarg, optind, pg_log_debug, pg_log_error, pg_log_error_hint, pg_logging_increase_verbosity(), pg_logging_init(), pg_strdup(), PG_TEXTDOMAIN, progname, restartWALFileName, set_pglocale_pgservice(), SetWALFileNameForCleanup(), and usage().

SetWALFileNameForCleanup()

static void SetWALFileNameForCleanup ( void  )

static

Definition at line 175 of file pg_archivecleanup.c.

{
    bool        fnameOK = false;
 
    TrimExtension(restartWALFileName, additional_ext);
 
    /*
     * If restartWALFileName is a WAL file name then just use it directly. If
     * restartWALFileName is a .partial or .backup filename, make sure we use
     * the prefix of the filename, otherwise we will remove wrong files since
     * 000000010000000000000010.partial and
     * 000000010000000000000010.00000020.backup are after
     * 000000010000000000000010.
     */
    if (IsXLogFileName(restartWALFileName))
    {
        strcpy(exclusiveCleanupFileName, restartWALFileName);
        fnameOK = true;
    }
    else if (IsPartialXLogFileName(restartWALFileName))
    {
        int         args;
        uint32      tli = 1,
                    log = 0,
                    seg = 0;
 
        args = sscanf(restartWALFileName, "%08X%08X%08X.partial",
                      &tli, &log, &seg);
        if (args == 3)
        {
            fnameOK = true;
 
            /*
             * Use just the prefix of the filename, ignore everything after
             * first period
             */
            XLogFileNameById(exclusiveCleanupFileName, tli, log, seg);
        }
    }
    else if (IsBackupHistoryFileName(restartWALFileName))
    {
        int         args;
        uint32      tli = 1,
                    log = 0,
                    seg = 0,
                    offset = 0;
 
        args = sscanf(restartWALFileName, "%08X%08X%08X.%08X.backup", &tli, &log, &seg, &offset);
        if (args == 4)
        {
            fnameOK = true;
 
            /*
             * Use just the prefix of the filename, ignore everything after
             * first period
             */
            XLogFileNameById(exclusiveCleanupFileName, tli, log, seg);
        }
    }
 
    if (!fnameOK)
    {
        pg_log_error("invalid file name argument");
        pg_log_error_hint("Try \"%s --help\" for more information.", progname);
        exit(2);
    }
}

References additional_ext, generate_unaccent_rules::args, exclusiveCleanupFileName, exit(), IsBackupHistoryFileName(), IsPartialXLogFileName(), IsXLogFileName(), pg_log_error, pg_log_error_hint, progname, restartWALFileName, TrimExtension(), and XLogFileNameById().

Referenced by main().

TrimExtension()

static void TrimExtension ( char *  filename, char *  extension  )

static

Definition at line 73 of file pg_archivecleanup.c.

{
    int         flen;
    int         elen;
 
    if (extension == NULL)
        return;
 
    elen = strlen(extension);
    flen = strlen(filename);
 
    if (flen > elen && strcmp(filename + flen - elen, extension) == 0)
        filename[flen - elen] = '\0';
}

References filename.

Referenced by CleanupPriorWALFiles(), and SetWALFileNameForCleanup().

usage()

static void usage ( void  )

static

Definition at line 249 of file pg_archivecleanup.c.

{
    printf(_("%s removes older WAL files from PostgreSQL archives.\n\n"), progname);
    printf(_("Usage:\n"));
    printf(_("  %s [OPTION]... ARCHIVELOCATION OLDESTKEPTWALFILE\n"), progname);
    printf(_("\nOptions:\n"));
    printf(_("  -d             generate debug output (verbose mode)\n"));
    printf(_("  -n             dry run, show the names of the files that would be removed\n"));
    printf(_("  -V, --version  output version information, then exit\n"));
    printf(_("  -x EXT         clean up files if they have this extension\n"));
    printf(_("  -?, --help     show this help, then exit\n"));
    printf(_("\n"
             "For use as archive_cleanup_command in postgresql.conf:\n"
             "  archive_cleanup_command = 'pg_archivecleanup [OPTION]... ARCHIVELOCATION %%r'\n"
             "e.g.\n"
             "  archive_cleanup_command = 'pg_archivecleanup /mnt/server/archiverdir %%r'\n"));
    printf(_("\n"
             "Or for use as a standalone archive cleaner:\n"
             "e.g.\n"
             "  pg_archivecleanup /mnt/server/archiverdir 000000010000000000000010.00000020.backup\n"));
    printf(_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
    printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
}

References _, printf, and progname.

Referenced by main().

Variable Documentation

additional_ext

char* additional_ext = NULL

Definition at line 26 of file pg_archivecleanup.c.

Referenced by CleanupPriorWALFiles(), main(), and SetWALFileNameForCleanup().

archiveLocation

char* archiveLocation

Definition at line 28 of file pg_archivecleanup.c.

Referenced by CleanupPriorWALFiles(), Initialize(), and main().

dryrun

bool dryrun = false

Definition at line 25 of file pg_archivecleanup.c.

Referenced by CleanupPriorWALFiles(), and main().

exclusiveCleanupFileName

char exclusiveCleanupFileName[MAXFNAMELEN]

Definition at line 30 of file pg_archivecleanup.c.

Referenced by CleanupPriorWALFiles(), main(), and SetWALFileNameForCleanup().

progname

const char* progname

Definition at line 22 of file pg_archivecleanup.c.

Referenced by main(), SetWALFileNameForCleanup(), and usage().

restartWALFileName

char* restartWALFileName

Definition at line 29 of file pg_archivecleanup.c.

Referenced by main(), and SetWALFileNameForCleanup().