--- /dev/null
+/*
+ * $PostgreSQL: pgsql/contrib/pg_archivecleanup/pg_archivecleanup.c,v 1.1 2010/06/14 16:19:24 sriggs Exp $
+ *
+ * pg_archivecleanup.c
+ *
+ * Production-ready example of an archive_cleanup_command
+ * used to clean an archive when using standby_mode = on in 9.0
+ * or for standalone use for any version of PostgreSQL 8.0+.
+ *
+ * Original author: Simon Riggs simon@2ndquadrant.com
+ * Current maintainer: Simon Riggs
+ */
+#include "postgres_fe.h"
+
+#include <ctype.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <signal.h>
+
+#ifdef WIN32
+int getopt(int argc, char *const argv[], const char *optstring);
+#else
+#include <sys/time.h>
+#include <unistd.h>
+
+#ifdef HAVE_GETOPT_H
+#include <getopt.h>
+#endif
+#endif /* ! WIN32 */
+
+extern char *optarg;
+extern int optind;
+
+const char *progname;
+
+/* Options and defaults */
+bool debug = false; /* are we debugging? */
+
+char *archiveLocation; /* where to find the archive? */
+char *restartWALFileName; /* the file from which we can restart restore */
+char WALFilePath[MAXPGPATH]; /* the file path including archive */
+char exclusiveCleanupFileName[MAXPGPATH]; /* the oldest file we want to
+ * remain in archive */
+
+struct stat stat_buf;
+
+/* =====================================================================
+ *
+ * Customizable section
+ *
+ * =====================================================================
+ *
+ * Currently, this section assumes that the Archive is a locally
+ * accessible directory. If you want to make other assumptions,
+ * such as using a vendor-specific archive and access API, these
+ * routines are the ones you'll need to change. You're
+ * enouraged to submit any changes to pgsql-hackers@postgresql.org
+ * or personally to the current maintainer. Those changes may be
+ * folded in to later versions of this program.
+ */
+
+#define XLOG_DATA_FNAME_LEN 24
+/* Reworked from access/xlog_internal.h */
+#define XLogFileName(fname, tli, log, seg) \
+ snprintf(fname, XLOG_DATA_FNAME_LEN + 1, "%08X%08X%08X", tli, log, seg)
+#define XLOG_BACKUP_FNAME_LEN 40
+
+/*
+ * Initialize allows customized commands into the archive cleanup program.
+ *
+ * You may wish to add code to check for tape libraries, etc..
+ */
+static void
+Initialize(void)
+{
+ /*
+ * This code assumes that archiveLocation is a directory, so we use
+ * stat to test if it's accessible.
+ */
+ if (stat(archiveLocation, &stat_buf) != 0)
+ {
+ fprintf(stderr, "%s: archiveLocation \"%s\" does not exist\n", progname, archiveLocation);
+ fflush(stderr);
+ exit(2);
+ }
+}
+
+static void
+CleanupPriorWALFiles(void)
+{
+ int rc;
+ DIR *xldir;
+ struct dirent *xlde;
+
+ if ((xldir = opendir(archiveLocation)) != NULL)
+ {
+ while ((xlde = readdir(xldir)) != NULL)
+ {
+ /*
+ * 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 (strlen(xlde->d_name) == XLOG_DATA_FNAME_LEN &&
+ strspn(xlde->d_name, "0123456789ABCDEF") == XLOG_DATA_FNAME_LEN &&
+ strcmp(xlde->d_name + 8, exclusiveCleanupFileName + 8) < 0)
+ {
+#ifdef WIN32
+ snprintf(WALFilePath, MAXPGPATH, "%s\\%s", archiveLocation, xlde->d_name);
+#else
+ snprintf(WALFilePath, MAXPGPATH, "%s/%s", archiveLocation, xlde->d_name);
+#endif
+
+ if (debug)
+ fprintf(stderr, "\n%s: removing \"%s\"", progname, WALFilePath);
+
+ rc = unlink(WALFilePath);
+ if (rc != 0)
+ {
+ fprintf(stderr, "\n%s: ERROR failed to remove \"%s\": %s",
+ progname, WALFilePath, strerror(errno));
+ break;
+ }
+ }
+ }
+ if (debug)
+ fprintf(stderr, "\n");
+ }
+ else
+ fprintf(stderr, "%s: archiveLocation \"%s\" open error\n", progname, archiveLocation);
+
+ closedir(xldir);
+ fflush(stderr);
+}
+
+/*
+ * SetWALFileNameForCleanup()
+ *
+ * Set the earliest WAL filename that we want to keep on the archive
+ * and decide whether we need_cleanup
+ */
+static void
+SetWALFileNameForCleanup(void)
+{
+ bool fnameOK = false;
+
+ /*
+ * If restartWALFileName is a WAL file name then just use it directly.
+ * If restartWALFileName is a .backup filename, make sure we use
+ * the prefix of the filename, otherwise we will remove wrong files
+ * since 000000010000000000000010.00000020.backup is after
+ * 000000010000000000000010.
+ */
+ if (strlen(restartWALFileName) == XLOG_DATA_FNAME_LEN &&
+ strspn(restartWALFileName, "0123456789ABCDEF") == XLOG_DATA_FNAME_LEN)
+ {
+ strcpy(exclusiveCleanupFileName, restartWALFileName);
+ fnameOK = true;
+ }
+ else if (strlen(restartWALFileName) == XLOG_BACKUP_FNAME_LEN)
+ {
+ 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
+ */
+ XLogFileName(exclusiveCleanupFileName, tli, log, seg);
+ }
+ }
+
+ if (!fnameOK)
+ {
+ fprintf(stderr, "%s: invalid filename input\n", progname);
+ fprintf(stderr, "Try \"%s --help\" for more information.\n", progname);
+ exit(2);
+ }
+}
+
+/* =====================================================================
+ * End of Customizable section
+ * =====================================================================
+ */
+
+static void
+usage(void)
+{
+ printf("%s removes older WAL files from PostgreSQL archives.\n\n", progname);
+ printf("Usage:\n");
+ printf(" %s [OPTION]... ARCHIVELOCATION OLDESTKEPTWALFILE\n", progname);
+ printf("\n"
+ "for use as an archive_cleanup_command in the recovery.conf when standby_mode = on:\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("\nOptions:\n");
+ printf(" -d generates debug output (verbose mode)\n");
+ printf(" --help show this help, then exit\n");
+ printf(" --version output version information, then exit\n");
+ printf("\nReport bugs to <pgsql-bugs@postgresql.org>.\n");
+}
+
+/*------------ MAIN ----------------------------------------*/
+int
+main(int argc, char **argv)
+{
+ int c;
+
+ 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, "d")) != -1)
+ {
+ switch (c)
+ {
+ case 'd': /* Debug mode */
+ debug = true;
+ break;
+ default:
+ fprintf(stderr, "Try \"%s --help\" for more information.\n", progname);
+ exit(2);
+ break;
+ }
+ }
+
+ /*
+ * 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
+ {
+ fprintf(stderr, "%s: must specify archive location\n", progname);
+ fprintf(stderr, "Try \"%s --help\" for more information.\n", progname);
+ exit(2);
+ }
+
+ if (optind < argc)
+ {
+ restartWALFileName = argv[optind];
+ optind++;
+ }
+ else
+ {
+ fprintf(stderr, "%s: must specify restartfilename\n", progname);
+ fprintf(stderr, "Try \"%s --help\" for more information.\n", progname);
+ exit(2);
+ }
+
+ if (optind < argc)
+ {
+ fprintf(stderr, "%s: too many parameters\n", progname);
+ fprintf(stderr, "Try \"%s --help\" for more information.\n", 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();
+
+ if (debug)
+ {
+ fprintf(stderr, "%s: keep WAL file %s and later", progname, exclusiveCleanupFileName);
+ fflush(stderr);
+ }
+
+ /*
+ * Remove WAL files older than cut-off
+ */
+ CleanupPriorWALFiles();
+
+ exit(0);
+}
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