--- /dev/null
+/*-------------------------------------------------------------------------
+ *
+ * pg_xlogdump.c - decode and display WAL
+ *
+ * Copyright (c) 2012, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * contrib/pg_xlogdump/pg_xlogdump.c
+ *-------------------------------------------------------------------------
+ */
+
+#define FRONTEND 1
+#include "postgres.h"
+
+#include
+#include
+
+#include "access/xlog.h"
+#include "access/xlogreader.h"
+#include "access/transam.h"
+#include "common/fe_memutils.h"
+#include "common/relpath.h"
+#include "getopt_long.h"
+#include "rmgrdesc.h"
+
+
+static const char *progname;
+
+typedef struct XLogDumpPrivate
+{
+ TimeLineID timeline;
+ char *inpath;
+ XLogRecPtr startptr;
+ XLogRecPtr endptr;
+} XLogDumpPrivate;
+
+typedef struct XLogDumpConfig
+{
+ /* display options */
+ bool bkp_details;
+ int stop_after_records;
+ int already_displayed_records;
+
+ /* filter options */
+ int filter_by_rmgr;
+ TransactionId filter_by_xid;
+ TransactionId filter_by_xid_enabled;
+} XLogDumpConfig;
+
+static void
+fatal_error(const char *fmt,...)
+__attribute__((format(PG_PRINTF_ATTRIBUTE, 1, 2)));
+
+/*
+ * Big red button to push when things go horribly wrong.
+ */
+static void
+fatal_error(const char *fmt,...)
+{
+ va_list args;
+
+ fflush(stdout);
+
+ fprintf(stderr, "%s: FATAL: ", progname);
+ va_start(args, fmt);
+ vfprintf(stderr, fmt, args);
+ va_end(args);
+ fputc('\n', stderr);
+
+ exit(EXIT_FAILURE);
+}
+
+static void
+print_rmgr_list(void)
+{
+ int i;
+
+ for (i = 0; i < RM_MAX_ID + 1; i++)
+ {
+ printf("%s\n", RmgrDescTable[i].rm_name);
+ }
+}
+
+/*
+ * Check whether directory exists and whether we can open it. Keep errno set so
+ * that the caller can report errors somewhat more accurately.
+ */
+static bool
+verify_directory(const char *directory)
+{
+ DIR *dir = opendir(directory);
+ if (dir == NULL)
+ return false;
+ closedir(dir);
+ return true;
+}
+
+/*
+ * Split a pathname as dirname(1) and basename(1) would.
+ *
+ * XXX this probably doesn't do very well on Windows. We probably need to
+ * apply canonicalize_path(), at the very least.
+ */
+static void
+split_path(const char *path, char **dir, char **fname)
+{
+ char *sep;
+
+ /* split filepath into directory & filename */
+ sep = strrchr(path, '/');
+
+ /* directory path */
+ if (sep != NULL)
+ {
+ *dir = pg_strdup(path);
+ (*dir)[(sep - path) + 1] = '\0'; /* no strndup */
+ *fname = pg_strdup(sep + 1);
+ }
+ /* local directory */
+ else
+ {
+ *dir = NULL;
+ *fname = pg_strdup(path);
+ }
+}
+
+/*
+ * Try to find the file in several places:
+ * if directory == NULL:
+ * fname
+ * XLOGDIR / fname
+ * $PGDATA / XLOGDIR / fname
+ * else
+ * directory / fname
+ * directory / XLOGDIR / fname
+ *
+ * return a read only fd
+ */
+static int
+fuzzy_open_file(const char *directory, const char *fname)
+{
+ int fd = -1;
+ char fpath[MAXPGPATH];
+
+ if (directory == NULL)
+ {
+ const char *datadir;
+
+ /* fname */
+ fd = open(fname, O_RDONLY | PG_BINARY, 0);
+ if (fd < 0 && errno != ENOENT)
+ return -1;
+ else if (fd > 0)
+ return fd;
+
+ /* XLOGDIR / fname */
+ snprintf(fpath, MAXPGPATH, "%s/%s",
+ XLOGDIR, fname);
+ fd = open(fpath, O_RDONLY | PG_BINARY, 0);
+ if (fd < 0 && errno != ENOENT)
+ return -1;
+ else if (fd > 0)
+ return fd;
+
+ datadir = getenv("PGDATA");
+ /* $PGDATA / XLOGDIR / fname */
+ if (datadir != NULL)
+ {
+ snprintf(fpath, MAXPGPATH, "%s/%s/%s",
+ datadir, XLOGDIR, fname);
+ fd = open(fpath, O_RDONLY | PG_BINARY, 0);
+ if (fd < 0 && errno != ENOENT)
+ return -1;
+ else if (fd > 0)
+ return fd;
+ }
+ }
+ else
+ {
+ /* directory / fname */
+ snprintf(fpath, MAXPGPATH, "%s/%s",
+ directory, fname);
+ fd = open(fpath, O_RDONLY | PG_BINARY, 0);
+ if (fd < 0 && errno != ENOENT)
+ return -1;
+ else if (fd > 0)
+ return fd;
+
+ /* directory / XLOGDIR / fname */
+ snprintf(fpath, MAXPGPATH, "%s/%s/%s",
+ directory, XLOGDIR, fname);
+ fd = open(fpath, O_RDONLY | PG_BINARY, 0);
+ if (fd < 0 && errno != ENOENT)
+ return -1;
+ else if (fd > 0)
+ return fd;
+ }
+ return -1;
+}
+
+/*
+ * Read count bytes from a segment file in the specified directory, for the
+ * given timeline, containing the specified record pointer; store the data in
+ * the passed buffer.
+ */
+static void
+XLogDumpXLogRead(const char *directory, TimeLineID timeline_id,
+ XLogRecPtr startptr, char *buf, Size count)
+{
+ char *p;
+ XLogRecPtr recptr;
+ Size nbytes;
+
+ static int sendFile = -1;
+ static XLogSegNo sendSegNo = 0;
+ static uint32 sendOff = 0;
+
+ p = buf;
+ recptr = startptr;
+ nbytes = count;
+
+ while (nbytes > 0)
+ {
+ uint32 startoff;
+ int segbytes;
+ int readbytes;
+
+ startoff = recptr % XLogSegSize;
+
+ if (sendFile < 0 || !XLByteInSeg(recptr, sendSegNo))
+ {
+ char fname[MAXFNAMELEN];
+
+ /* Switch to another logfile segment */
+ if (sendFile >= 0)
+ close(sendFile);
+
+ XLByteToSeg(recptr, sendSegNo);
+
+ XLogFileName(fname, timeline_id, sendSegNo);
+
+ sendFile = fuzzy_open_file(directory, fname);
+
+ if (sendFile < 0)
+ fatal_error("could not find file \"%s\": %s",
+ fname, strerror(errno));
+ sendOff = 0;
+ }
+
+ /* Need to seek in the file? */
+ if (sendOff != startoff)
+ {
+ if (lseek(sendFile, (off_t) startoff, SEEK_SET) < 0)
+ {
+ int err = errno;
+ char fname[MAXPGPATH];
+
+ XLogFileName(fname, timeline_id, sendSegNo);
+
+ fatal_error("could not seek in log segment %s to offset %u: %s",
+ fname, startoff, strerror(err));
+ }
+ sendOff = startoff;
+ }
+
+ /* How many bytes are within this segment? */
+ if (nbytes > (XLogSegSize - startoff))
+ segbytes = XLogSegSize - startoff;
+ else
+ segbytes = nbytes;
+
+ readbytes = read(sendFile, p, segbytes);
+ if (readbytes <= 0)
+ {
+ int err = errno;
+ char fname[MAXPGPATH];
+
+ XLogFileName(fname, timeline_id, sendSegNo);
+
+ fatal_error("could not read from log segment %s, offset %d, length %d: %s",
+ fname, sendOff, segbytes, strerror(err));
+ }
+
+ /* Update state for read */
+ recptr += readbytes;
+
+ sendOff += readbytes;
+ nbytes -= readbytes;
+ p += readbytes;
+ }
+}
+
+/*
+ * XLogReader read_page callback
+ */
+static int
+XLogDumpReadPage(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen,
+ XLogRecPtr targetPtr, char *readBuff, TimeLineID *curFileTLI)
+{
+ XLogDumpPrivate *private = state->private_data;
+ int count = XLOG_BLCKSZ;
+
+ if (private->endptr != InvalidXLogRecPtr)
+ {
+ if (targetPagePtr + XLOG_BLCKSZ <= private->endptr)
+ count = XLOG_BLCKSZ;
+ else if (targetPagePtr + reqLen <= private->endptr)
+ count = private->endptr - targetPagePtr;
+ else
+ return -1;
+ }
+
+ XLogDumpXLogRead(private->inpath, private->timeline, targetPagePtr,
+ readBuff, count);
+
+ return count;
+}
+
+/*
+ * Print a record to stdout
+ */
+static void
+XLogDumpDisplayRecord(XLogDumpConfig *config, XLogRecPtr ReadRecPtr, XLogRecord *record)
+{
+ const RmgrDescData *desc = &RmgrDescTable[record->xl_rmid];
+
+ if (config->filter_by_rmgr != -1 &&
+ config->filter_by_rmgr != record->xl_rmid)
+ return;
+
+ if (config->filter_by_xid_enabled &&
+ config->filter_by_xid != record->xl_xid)
+ return;
+
+ config->already_displayed_records++;
+
+ printf("rmgr: %-11s len (rec/tot): %6u/%6u, tx: %10u, lsn: %X/%08X, prev %X/%08X, bkp: %u%u%u%u, desc: ",
+ desc->rm_name,
+ record->xl_len, record->xl_tot_len,
+ record->xl_xid,
+ (uint32) (ReadRecPtr >> 32), (uint32) ReadRecPtr,
+ (uint32) (record->xl_prev >> 32), (uint32) record->xl_prev,
+ !!(XLR_BKP_BLOCK(0) & record->xl_info),
+ !!(XLR_BKP_BLOCK(1) & record->xl_info),
+ !!(XLR_BKP_BLOCK(2) & record->xl_info),
+ !!(XLR_BKP_BLOCK(3) & record->xl_info));
+
+ /* the desc routine will printf the description directly to stdout */
+ desc->rm_desc(NULL, record->xl_info, XLogRecGetData(record));
+
+ putchar('\n');
+
+ if (config->bkp_details)
+ {
+ int bkpnum;
+ char *blk = (char *) XLogRecGetData(record) + record->xl_len;
+
+ for (bkpnum = 0; bkpnum < XLR_MAX_BKP_BLOCKS; bkpnum++)
+ {
+ BkpBlock bkpb;
+
+ if (!(XLR_BKP_BLOCK(bkpnum) & record->xl_info))
+ continue;
+
+ memcpy(&bkpb, blk, sizeof(BkpBlock));
+ blk += sizeof(BkpBlock);
+ blk += BLCKSZ - bkpb.hole_length;
+
+ printf("\tbackup bkp #%u; rel %u/%u/%u; fork: %s; block: %u; hole: offset: %u, length: %u\n",
+ bkpnum,
+ bkpb.node.spcNode, bkpb.node.dbNode, bkpb.node.relNode,
+ forkNames[bkpb.fork],
+ bkpb.block, bkpb.hole_offset, bkpb.hole_length);
+ }
+ }
+}
+
+static void
+usage(void)
+{
+ printf("%s decodes and displays PostgreSQL transaction logs for debugging.\n\n",
+ progname);
+ printf("Usage:\n");
+ printf(" %s [OPTION] [STARTSEG [ENDSEG]] \n", progname);
+ printf("\nGeneral options:\n");
+ printf(" -V, --version output version information, then exit\n");
+ printf(" -?, --help show this help, then exit\n");
+ printf("\nContent options:\n");
+ printf(" -b, --bkp-details output detailed information about backup blocks\n");
+ printf(" -e, --end=RECPTR stop reading at log position RECPTR\n");
+ printf(" -n, --limit=N number of records to display\n");
+ printf(" -p, --path=PATH directory in which to find log segment files\n");
+ printf(" (default: ./pg_xlog)\n");
+ printf(" -r, --rmgr=RMGR only show records generated by resource manager RMGR\n");
+ printf(" use --rmgr=list to list valid resource manager names\n");
+ printf(" -s, --start=RECPTR stop reading at log position RECPTR\n");
+ printf(" -t, --timeline=TLI timeline from which to read log records\n");
+ printf(" (default: 1 or the value used in STARTSEG)\n");
+ printf(" -x, --xid=XID only show records with TransactionId XID\n");
+}
+
+int
+main(int argc, char **argv)
+{
+ uint32 xlogid;
+ uint32 xrecoff;
+ XLogReaderState *xlogreader_state;
+ XLogDumpPrivate private;
+ XLogDumpConfig config;
+ XLogRecord *record;
+ XLogRecPtr first_record;
+ char *errormsg;
+
+ static struct option long_options[] = {
+ {"bkp-details", no_argument, NULL, 'b'},
+ {"end", required_argument, NULL, 'e'},
+ {"help", no_argument, NULL, '?'},
+ {"limit", required_argument, NULL, 'n'},
+ {"path", required_argument, NULL, 'p'},
+ {"rmgr", required_argument, NULL, 'r'},
+ {"start", required_argument, NULL, 's'},
+ {"timeline", required_argument, NULL, 't'},
+ {"xid", required_argument, NULL, 'x'},
+ {"version", no_argument, NULL, 'V'},
+ {NULL, 0, NULL, 0}
+ };
+
+ int option;
+ int optindex = 0;
+
+ progname = get_progname(argv[0]);
+
+ memset(&private, 0, sizeof(XLogDumpPrivate));
+ memset(&config, 0, sizeof(XLogDumpConfig));
+
+ private.timeline = 1;
+ private.startptr = InvalidXLogRecPtr;
+ private.endptr = InvalidXLogRecPtr;
+
+ config.bkp_details = false;
+ config.stop_after_records = -1;
+ config.already_displayed_records = 0;
+ config.filter_by_rmgr = -1;
+ config.filter_by_xid = InvalidTransactionId;
+ config.filter_by_xid_enabled = false;
+
+ if (argc <= 1)
+ {
+ fprintf(stderr, "%s: no arguments specified\n", progname);
+ goto bad_argument;
+ }
+
+ while ((option = getopt_long(argc, argv, "be:?n:p:r:s:t:Vx:",
+ long_options, &optindex)) != -1)
+ {
+ switch (option)
+ {
+ case 'b':
+ config.bkp_details = true;
+ break;
+ case 'e':
+ if (sscanf(optarg, "%X/%X", &xlogid, &xrecoff) != 2)
+ {
+ fprintf(stderr, "%s: could not parse end log position \"%s\"\n",
+ progname, optarg);
+ goto bad_argument;
+ }
+ private.endptr = (uint64) xlogid << 32 | xrecoff;
+ break;
+ case '?':
+ usage();
+ exit(EXIT_SUCCESS);
+ break;
+ case 'n':
+ if (sscanf(optarg, "%d", &config.stop_after_records) != 1)
+ {
+ fprintf(stderr, "%s: could not parse limit \"%s\"\n",
+ progname, optarg);
+ goto bad_argument;
+ }
+ break;
+ case 'p':
+ private.inpath = pg_strdup(optarg);
+ break;
+ case 'r':
+ {
+ int i;
+
+ if (pg_strcasecmp(optarg, "list") == 0)
+ {
+ print_rmgr_list();
+ exit(EXIT_SUCCESS);
+ }
+
+ for (i = 0; i < RM_MAX_ID; i++)
+ {
+ if (pg_strcasecmp(optarg, RmgrDescTable[i].rm_name) == 0)
+ {
+ config.filter_by_rmgr = i;
+ break;
+ }
+ }
+
+ if (config.filter_by_rmgr == -1)
+ {
+ fprintf(stderr, "%s: resource manager \"%s\" does not exist\n",
+ progname, optarg);
+ goto bad_argument;
+ }
+ }
+ break;
+ case 's':
+ if (sscanf(optarg, "%X/%X", &xlogid, &xrecoff) != 2)
+ {
+ fprintf(stderr, "%s: could not parse end log position \"%s\"\n",
+ progname, optarg);
+ goto bad_argument;
+ }
+ else
+ private.startptr = (uint64) xlogid << 32 | xrecoff;
+ break;
+ case 't':
+ if (sscanf(optarg, "%d", &private.timeline) != 1)
+ {
+ fprintf(stderr, "%s: could not parse timeline \"%s\"\n",
+ progname, optarg);
+ goto bad_argument;
+ }
+ break;
+ case 'V':
+ puts("pg_xlogdump (PostgreSQL) " PG_VERSION);
+ exit(EXIT_SUCCESS);
+ break;
+ case 'x':
+ if (sscanf(optarg, "%u", &config.filter_by_xid) != 1)
+ {
+ fprintf(stderr, "%s: could not parse \"%s\" as a valid xid\n",
+ progname, optarg);
+ goto bad_argument;
+ }
+ config.filter_by_xid_enabled = true;
+ break;
+ default:
+ goto bad_argument;
+ }
+ }
+
+ if ((optind + 2) < argc)
+ {
+ fprintf(stderr,
+ "%s: too many command-line arguments (first is \"%s\")\n",
+ progname, argv[optind + 2]);
+ goto bad_argument;
+ }
+
+ if (private.inpath != NULL)
+ {
+ /* validate path points to directory */
+ if (!verify_directory(private.inpath))
+ {
+ fprintf(stderr,
+ "%s: path \"%s\" cannot be opened: %s",
+ progname, private.inpath, strerror(errno));
+ goto bad_argument;
+ }
+ }
+
+ /* parse files as start/end boundaries, extract path if not specified */
+ if (optind < argc)
+ {
+ char *directory = NULL;
+ char *fname = NULL;
+ int fd;
+ XLogSegNo segno;
+
+ split_path(argv[optind], &directory, &fname);
+
+ if (private.inpath == NULL && directory != NULL)
+ {
+ private.inpath = directory;
+
+ if (!verify_directory(private.inpath))
+ fatal_error("cannot open directory \"%s\": %s",
+ private.inpath, strerror(errno));
+ }
+
+ fd = fuzzy_open_file(private.inpath, fname);
+ if (fd < 0)
+ fatal_error("could not open file \"%s\"", fname);
+ close(fd);
+
+ /* parse position from file */
+ XLogFromFileName(fname, &private.timeline, &segno);
+
+ if (XLogRecPtrIsInvalid(private.startptr))
+ XLogSegNoOffsetToRecPtr(segno, 0, private.startptr);
+ else if (!XLByteInSeg(private.startptr, segno))
+ {
+ fprintf(stderr,
+ "%s: start log position %X/%X is not inside file \"%s\"\n",
+ progname,
+ (uint32) (private.startptr >> 32),
+ (uint32) private.startptr,
+ fname);
+ goto bad_argument;
+ }
+
+ /* no second file specified, set end position */
+ if (!(optind + 1 < argc) && XLogRecPtrIsInvalid(private.endptr))
+ XLogSegNoOffsetToRecPtr(segno + 1, 0, private.endptr);
+
+ /* parse ENDSEG if passed */
+ if (optind + 1 < argc)
+ {
+ XLogSegNo endsegno;
+
+ /* ignore directory, already have that */
+ split_path(argv[optind + 1], &directory, &fname);
+
+ fd = fuzzy_open_file(private.inpath, fname);
+ if (fd < 0)
+ fatal_error("could not open file \"%s\"", fname);
+ close(fd);
+
+ /* parse position from file */
+ XLogFromFileName(fname, &private.timeline, &endsegno);
+
+ if (endsegno < segno)
+ fatal_error("ENDSEG %s is before STARTSEG %s",
+ argv[optind + 1], argv[optind]);
+
+ if (XLogRecPtrIsInvalid(private.endptr))
+ XLogSegNoOffsetToRecPtr(endsegno + 1, 0, private.endptr);
+
+ /* set segno to endsegno for check of --end */
+ segno = endsegno;
+ }
+
+
+ if (!XLByteInSeg(private.endptr, segno) &&
+ private.endptr != (segno + 1) * XLogSegSize)
+ {
+ fprintf(stderr,
+ "%s: end log position %X/%X is not inside file \"%s\"\n",
+ progname,
+ (uint32) (private.endptr >> 32),
+ (uint32) private.endptr,
+ argv[argc - 1]);
+ goto bad_argument;
+ }
+ }
+
+ /* we don't know what to print */
+ if (XLogRecPtrIsInvalid(private.startptr))
+ {
+ fprintf(stderr, "%s: no start log position given in range mode.\n", progname);
+ goto bad_argument;
+ }
+
+ /* done with argument parsing, do the actual work */
+
+ /* we have everything we need, start reading */
+ xlogreader_state = XLogReaderAllocate(XLogDumpReadPage, &private);
+ if (!xlogreader_state)
+ fatal_error("out of memory");
+
+ /* first find a valid recptr to start from */
+ first_record = XLogFindNextRecord(xlogreader_state, private.startptr);
+
+ if (first_record == InvalidXLogRecPtr)
+ fatal_error("could not find a valid record after %X/%X",
+ (uint32) (private.startptr >> 32),
+ (uint32) private.startptr);
+
+ /*
+ * Display a message that we're skipping data if `from` wasn't a pointer to
+ * the start of a record and also wasn't a pointer to the beginning of a
+ * segment (e.g. we were used in file mode).
+ */
+ if (first_record != private.startptr && (private.startptr % XLogSegSize) != 0)
+ printf("first record is after %X/%X, at %X/%X, skipping over %u bytes\n",
+ (uint32) (private.startptr >> 32), (uint32) private.startptr,
+ (uint32) (first_record >> 32), (uint32) first_record,
+ (uint32) (first_record - private.startptr));
+
+ while ((record = XLogReadRecord(xlogreader_state, first_record, &errormsg)))
+ {
+ /* continue after the last record */
+ first_record = InvalidXLogRecPtr;
+ XLogDumpDisplayRecord(&config, xlogreader_state->ReadRecPtr, record);
+
+ /* check whether we printed enough */
+ if (config.stop_after_records > 0 &&
+ config.already_displayed_records >= config.stop_after_records)
+ break;
+ }
+
+ if (errormsg)
+ fatal_error("error in WAL record at %X/%X: %s\n",
+ (uint32) (xlogreader_state->ReadRecPtr >> 32),
+ (uint32) xlogreader_state->ReadRecPtr,
+ errormsg);
+
+ XLogReaderFree(xlogreader_state);
+
+ return EXIT_SUCCESS;
+
+bad_argument:
+ fprintf(stderr, "Try \"%s --help\" for more information.\n", progname);
+ return EXIT_FAILURE;
+}
projects / postgresql.git / commitdiff