diff options
Diffstat (limited to 'src/bin/pg_resetwal/pg_resetwal.c')
| -rw-r--r-- | src/bin/pg_resetwal/pg_resetwal.c | 1184 |
1 files changed, 1184 insertions, 0 deletions
diff --git a/src/bin/pg_resetwal/pg_resetwal.c b/src/bin/pg_resetwal/pg_resetwal.c new file mode 100644 index 00000000000..96b7097f8b7 --- /dev/null +++ b/src/bin/pg_resetwal/pg_resetwal.c @@ -0,0 +1,1184 @@ +/*------------------------------------------------------------------------- + * + * pg_resetwal.c + * A utility to "zero out" the xlog when it's corrupt beyond recovery. + * Can also rebuild pg_control if needed. + * + * The theory of operation is fairly simple: + * 1. Read the existing pg_control (which will include the last + * checkpoint record). If it is an old format then update to + * current format. + * 2. If pg_control is corrupt, attempt to intuit reasonable values, + * by scanning the old xlog if necessary. + * 3. Modify pg_control to reflect a "shutdown" state with a checkpoint + * record at the start of xlog. + * 4. Flush the existing xlog files and write a new segment with + * just a checkpoint record in it. The new segment is positioned + * just past the end of the old xlog, so that existing LSNs in + * data pages will appear to be "in the past". + * This is all pretty straightforward except for the intuition part of + * step 2 ... + * + * + * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/bin/pg_resetwal/pg_resetwal.c + * + *------------------------------------------------------------------------- + */ + +/* + * We have to use postgres.h not postgres_fe.h here, because there's so much + * backend-only stuff in the XLOG include files we need. But we need a + * frontend-ish environment otherwise. Hence this ugly hack. + */ +#define FRONTEND 1 + +#include "postgres.h" + +#include <dirent.h> +#include <fcntl.h> +#include <locale.h> +#include <sys/stat.h> +#include <sys/time.h> +#include <time.h> +#include <unistd.h> + +#include "access/transam.h" +#include "access/tuptoaster.h" +#include "access/multixact.h" +#include "access/xlog.h" +#include "access/xlog_internal.h" +#include "catalog/catversion.h" +#include "catalog/pg_control.h" +#include "common/fe_memutils.h" +#include "common/restricted_token.h" +#include "storage/large_object.h" +#include "pg_getopt.h" + + +static ControlFileData ControlFile; /* pg_control values */ +static XLogSegNo newXlogSegNo; /* new XLOG segment # */ +static bool guessed = false; /* T if we had to guess at any values */ +static const char *progname; +static uint32 set_xid_epoch = (uint32) -1; +static TransactionId set_xid = 0; +static TransactionId set_oldest_commit_ts_xid = 0; +static TransactionId set_newest_commit_ts_xid = 0; +static Oid set_oid = 0; +static MultiXactId set_mxid = 0; +static MultiXactOffset set_mxoff = (MultiXactOffset) -1; +static uint32 minXlogTli = 0; +static XLogSegNo minXlogSegNo = 0; + +static bool ReadControlFile(void); +static void GuessControlValues(void); +static void PrintControlValues(bool guessed); +static void PrintNewControlValues(void); +static void RewriteControlFile(void); +static void FindEndOfXLOG(void); +static void KillExistingXLOG(void); +static void KillExistingArchiveStatus(void); +static void WriteEmptyXLOG(void); +static void usage(void); + + +int +main(int argc, char *argv[]) +{ + int c; + bool force = false; + bool noupdate = false; + MultiXactId set_oldestmxid = 0; + char *endptr; + char *endptr2; + char *DataDir = NULL; + int fd; + + set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_resetwal")); + + 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_resetwal (PostgreSQL) " PG_VERSION); + exit(0); + } + } + + + while ((c = getopt(argc, argv, "c:D:e:fl:m:no:O:x:")) != -1) + { + switch (c) + { + case 'D': + DataDir = optarg; + break; + + case 'f': + force = true; + break; + + case 'n': + noupdate = true; + break; + + case 'e': + set_xid_epoch = strtoul(optarg, &endptr, 0); + if (endptr == optarg || *endptr != '\0') + { + /*------ + translator: the second %s is a command line argument (-e, etc) */ + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-e"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + if (set_xid_epoch == -1) + { + fprintf(stderr, _("%s: transaction ID epoch (-e) must not be -1\n"), progname); + exit(1); + } + break; + + case 'x': + set_xid = strtoul(optarg, &endptr, 0); + if (endptr == optarg || *endptr != '\0') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-x"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + if (set_xid == 0) + { + fprintf(stderr, _("%s: transaction ID (-x) must not be 0\n"), progname); + exit(1); + } + break; + + case 'c': + set_oldest_commit_ts_xid = strtoul(optarg, &endptr, 0); + if (endptr == optarg || *endptr != ',') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-c"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + set_newest_commit_ts_xid = strtoul(endptr + 1, &endptr2, 0); + if (endptr2 == endptr + 1 || *endptr2 != '\0') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-c"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + + if (set_oldest_commit_ts_xid < 2 && + set_oldest_commit_ts_xid != 0) + { + fprintf(stderr, _("%s: transaction ID (-c) must be either 0 or greater than or equal to 2\n"), progname); + exit(1); + } + + if (set_newest_commit_ts_xid < 2 && + set_newest_commit_ts_xid != 0) + { + fprintf(stderr, _("%s: transaction ID (-c) must be either 0 or greater than or equal to 2\n"), progname); + exit(1); + } + break; + + case 'o': + set_oid = strtoul(optarg, &endptr, 0); + if (endptr == optarg || *endptr != '\0') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-o"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + if (set_oid == 0) + { + fprintf(stderr, _("%s: OID (-o) must not be 0\n"), progname); + exit(1); + } + break; + + case 'm': + set_mxid = strtoul(optarg, &endptr, 0); + if (endptr == optarg || *endptr != ',') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-m"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + + set_oldestmxid = strtoul(endptr + 1, &endptr2, 0); + if (endptr2 == endptr + 1 || *endptr2 != '\0') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-m"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + if (set_mxid == 0) + { + fprintf(stderr, _("%s: multitransaction ID (-m) must not be 0\n"), progname); + exit(1); + } + + /* + * XXX It'd be nice to have more sanity checks here, e.g. so + * that oldest is not wrapped around w.r.t. nextMulti. + */ + if (set_oldestmxid == 0) + { + fprintf(stderr, _("%s: oldest multitransaction ID (-m) must not be 0\n"), + progname); + exit(1); + } + break; + + case 'O': + set_mxoff = strtoul(optarg, &endptr, 0); + if (endptr == optarg || *endptr != '\0') + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-O"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + if (set_mxoff == -1) + { + fprintf(stderr, _("%s: multitransaction offset (-O) must not be -1\n"), progname); + exit(1); + } + break; + + case 'l': + if (strspn(optarg, "01234567890ABCDEFabcdef") != XLOG_FNAME_LEN) + { + fprintf(stderr, _("%s: invalid argument for option %s\n"), progname, "-l"); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + XLogFromFileName(optarg, &minXlogTli, &minXlogSegNo); + break; + + default: + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + } + + if (DataDir == NULL && optind < argc) + DataDir = argv[optind++]; + + /* Complain if any arguments remain */ + if (optind < argc) + { + fprintf(stderr, _("%s: too many command-line arguments (first is \"%s\")\n"), + progname, argv[optind]); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), + progname); + exit(1); + } + + if (DataDir == NULL) + { + fprintf(stderr, _("%s: no data directory specified\n"), progname); + fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); + exit(1); + } + + /* + * Don't allow pg_resetwal to be run as root, to avoid overwriting the + * ownership of files in the data directory. We need only check for root + * -- any other user won't have sufficient permissions to modify files in + * the data directory. + */ +#ifndef WIN32 + if (geteuid() == 0) + { + fprintf(stderr, _("%s: cannot be executed by \"root\"\n"), + progname); + fprintf(stderr, _("You must run %s as the PostgreSQL superuser.\n"), + progname); + exit(1); + } +#endif + + get_restricted_token(progname); + + if (chdir(DataDir) < 0) + { + fprintf(stderr, _("%s: could not change directory to \"%s\": %s\n"), + progname, DataDir, strerror(errno)); + exit(1); + } + + /* + * Check for a postmaster lock file --- if there is one, refuse to + * proceed, on grounds we might be interfering with a live installation. + */ + if ((fd = open("postmaster.pid", O_RDONLY, 0)) < 0) + { + if (errno != ENOENT) + { + fprintf(stderr, _("%s: could not open file \"%s\" for reading: %s\n"), + progname, "postmaster.pid", strerror(errno)); + exit(1); + } + } + else + { + fprintf(stderr, _("%s: lock file \"%s\" exists\n" + "Is a server running? If not, delete the lock file and try again.\n"), + progname, "postmaster.pid"); + exit(1); + } + + /* + * Attempt to read the existing pg_control file + */ + if (!ReadControlFile()) + GuessControlValues(); + + /* + * Also look at existing segment files to set up newXlogSegNo + */ + FindEndOfXLOG(); + + /* + * If we're not going to proceed with the reset, print the current control + * file parameters. + */ + if ((guessed && !force) || noupdate) + PrintControlValues(guessed); + + /* + * Adjust fields if required by switches. (Do this now so that printout, + * if any, includes these values.) + */ + if (set_xid_epoch != -1) + ControlFile.checkPointCopy.nextXidEpoch = set_xid_epoch; + + if (set_xid != 0) + { + ControlFile.checkPointCopy.nextXid = set_xid; + + /* + * For the moment, just set oldestXid to a value that will force + * immediate autovacuum-for-wraparound. It's not clear whether adding + * user control of this is useful, so let's just do something that's + * reasonably safe. The magic constant here corresponds to the + * maximum allowed value of autovacuum_freeze_max_age. + */ + ControlFile.checkPointCopy.oldestXid = set_xid - 2000000000; + if (ControlFile.checkPointCopy.oldestXid < FirstNormalTransactionId) + ControlFile.checkPointCopy.oldestXid += FirstNormalTransactionId; + ControlFile.checkPointCopy.oldestXidDB = InvalidOid; + } + + if (set_oldest_commit_ts_xid != 0) + ControlFile.checkPointCopy.oldestCommitTsXid = set_oldest_commit_ts_xid; + if (set_newest_commit_ts_xid != 0) + ControlFile.checkPointCopy.newestCommitTsXid = set_newest_commit_ts_xid; + + if (set_oid != 0) + ControlFile.checkPointCopy.nextOid = set_oid; + + if (set_mxid != 0) + { + ControlFile.checkPointCopy.nextMulti = set_mxid; + + ControlFile.checkPointCopy.oldestMulti = set_oldestmxid; + if (ControlFile.checkPointCopy.oldestMulti < FirstMultiXactId) + ControlFile.checkPointCopy.oldestMulti += FirstMultiXactId; + ControlFile.checkPointCopy.oldestMultiDB = InvalidOid; + } + + if (set_mxoff != -1) + ControlFile.checkPointCopy.nextMultiOffset = set_mxoff; + + if (minXlogTli > ControlFile.checkPointCopy.ThisTimeLineID) + { + ControlFile.checkPointCopy.ThisTimeLineID = minXlogTli; + ControlFile.checkPointCopy.PrevTimeLineID = minXlogTli; + } + + if (minXlogSegNo > newXlogSegNo) + newXlogSegNo = minXlogSegNo; + + /* + * If we had to guess anything, and -f was not given, just print the + * guessed values and exit. Also print if -n is given. + */ + if ((guessed && !force) || noupdate) + { + PrintNewControlValues(); + if (!noupdate) + { + printf(_("\nIf these values seem acceptable, use -f to force reset.\n")); + exit(1); + } + else + exit(0); + } + + /* + * Don't reset from a dirty pg_control without -f, either. + */ + if (ControlFile.state != DB_SHUTDOWNED && !force) + { + printf(_("The database server was not shut down cleanly.\n" + "Resetting the transaction log might cause data to be lost.\n" + "If you want to proceed anyway, use -f to force reset.\n")); + exit(1); + } + + /* + * Else, do the dirty deed. + */ + RewriteControlFile(); + KillExistingXLOG(); + KillExistingArchiveStatus(); + WriteEmptyXLOG(); + + printf(_("Transaction log reset\n")); + return 0; +} + + +/* + * Try to read the existing pg_control file. + * + * This routine is also responsible for updating old pg_control versions + * to the current format. (Currently we don't do anything of the sort.) + */ +static bool +ReadControlFile(void) +{ + int fd; + int len; + char *buffer; + pg_crc32c crc; + + if ((fd = open(XLOG_CONTROL_FILE, O_RDONLY | PG_BINARY, 0)) < 0) + { + /* + * If pg_control is not there at all, or we can't read it, the odds + * are we've been handed a bad DataDir path, so give up. User can do + * "touch pg_control" to force us to proceed. + */ + fprintf(stderr, _("%s: could not open file \"%s\" for reading: %s\n"), + progname, XLOG_CONTROL_FILE, strerror(errno)); + if (errno == ENOENT) + fprintf(stderr, _("If you are sure the data directory path is correct, execute\n" + " touch %s\n" + "and try again.\n"), + XLOG_CONTROL_FILE); + exit(1); + } + + /* Use malloc to ensure we have a maxaligned buffer */ + buffer = (char *) pg_malloc(PG_CONTROL_SIZE); + + len = read(fd, buffer, PG_CONTROL_SIZE); + if (len < 0) + { + fprintf(stderr, _("%s: could not read file \"%s\": %s\n"), + progname, XLOG_CONTROL_FILE, strerror(errno)); + exit(1); + } + close(fd); + + if (len >= sizeof(ControlFileData) && + ((ControlFileData *) buffer)->pg_control_version == PG_CONTROL_VERSION) + { + /* Check the CRC. */ + INIT_CRC32C(crc); + COMP_CRC32C(crc, + buffer, + offsetof(ControlFileData, crc)); + FIN_CRC32C(crc); + + if (EQ_CRC32C(crc, ((ControlFileData *) buffer)->crc)) + { + /* Valid data... */ + memcpy(&ControlFile, buffer, sizeof(ControlFile)); + return true; + } + + fprintf(stderr, _("%s: pg_control exists but has invalid CRC; proceed with caution\n"), + progname); + /* We will use the data anyway, but treat it as guessed. */ + memcpy(&ControlFile, buffer, sizeof(ControlFile)); + guessed = true; + return true; + } + + /* Looks like it's a mess. */ + fprintf(stderr, _("%s: pg_control exists but is broken or unknown version; ignoring it\n"), + progname); + return false; +} + + +/* + * Guess at pg_control values when we can't read the old ones. + */ +static void +GuessControlValues(void) +{ + uint64 sysidentifier; + struct timeval tv; + + /* + * Set up a completely default set of pg_control values. + */ + guessed = true; + memset(&ControlFile, 0, sizeof(ControlFile)); + + ControlFile.pg_control_version = PG_CONTROL_VERSION; + ControlFile.catalog_version_no = CATALOG_VERSION_NO; + + /* + * Create a new unique installation identifier, since we can no longer use + * any old XLOG records. See notes in xlog.c about the algorithm. + */ + gettimeofday(&tv, NULL); + sysidentifier = ((uint64) tv.tv_sec) << 32; + sysidentifier |= ((uint64) tv.tv_usec) << 12; + sysidentifier |= getpid() & 0xFFF; + + ControlFile.system_identifier = sysidentifier; + + ControlFile.checkPointCopy.redo = SizeOfXLogLongPHD; + ControlFile.checkPointCopy.ThisTimeLineID = 1; + ControlFile.checkPointCopy.PrevTimeLineID = 1; + ControlFile.checkPointCopy.fullPageWrites = false; + ControlFile.checkPointCopy.nextXidEpoch = 0; + ControlFile.checkPointCopy.nextXid = FirstNormalTransactionId; + ControlFile.checkPointCopy.nextOid = FirstBootstrapObjectId; + ControlFile.checkPointCopy.nextMulti = FirstMultiXactId; + ControlFile.checkPointCopy.nextMultiOffset = 0; + ControlFile.checkPointCopy.oldestXid = FirstNormalTransactionId; + ControlFile.checkPointCopy.oldestXidDB = InvalidOid; + ControlFile.checkPointCopy.oldestMulti = FirstMultiXactId; + ControlFile.checkPointCopy.oldestMultiDB = InvalidOid; + ControlFile.checkPointCopy.time = (pg_time_t) time(NULL); + ControlFile.checkPointCopy.oldestActiveXid = InvalidTransactionId; + + ControlFile.state = DB_SHUTDOWNED; + ControlFile.time = (pg_time_t) time(NULL); + ControlFile.checkPoint = ControlFile.checkPointCopy.redo; + ControlFile.unloggedLSN = 1; + + /* minRecoveryPoint, backupStartPoint and backupEndPoint can be left zero */ + + ControlFile.wal_level = WAL_LEVEL_MINIMAL; + ControlFile.wal_log_hints = false; + ControlFile.track_commit_timestamp = false; + ControlFile.MaxConnections = 100; + ControlFile.max_worker_processes = 8; + ControlFile.max_prepared_xacts = 0; + ControlFile.max_locks_per_xact = 64; + + ControlFile.maxAlign = MAXIMUM_ALIGNOF; + ControlFile.floatFormat = FLOATFORMAT_VALUE; + ControlFile.blcksz = BLCKSZ; + ControlFile.relseg_size = RELSEG_SIZE; + ControlFile.xlog_blcksz = XLOG_BLCKSZ; + ControlFile.xlog_seg_size = XLOG_SEG_SIZE; + ControlFile.nameDataLen = NAMEDATALEN; + ControlFile.indexMaxKeys = INDEX_MAX_KEYS; + ControlFile.toast_max_chunk_size = TOAST_MAX_CHUNK_SIZE; + ControlFile.loblksize = LOBLKSIZE; +#ifdef HAVE_INT64_TIMESTAMP + ControlFile.enableIntTimes = true; +#else + ControlFile.enableIntTimes = false; +#endif + ControlFile.float4ByVal = FLOAT4PASSBYVAL; + ControlFile.float8ByVal = FLOAT8PASSBYVAL; + + /* + * XXX eventually, should try to grovel through old XLOG to develop more + * accurate values for TimeLineID, nextXID, etc. + */ +} + + +/* + * Print the guessed pg_control values when we had to guess. + * + * NB: this display should be just those fields that will not be + * reset by RewriteControlFile(). + */ +static void +PrintControlValues(bool guessed) +{ + char sysident_str[32]; + + if (guessed) + printf(_("Guessed pg_control values:\n\n")); + else + printf(_("Current pg_control values:\n\n")); + + /* + * Format system_identifier separately to keep platform-dependent format + * code out of the translatable message string. + */ + snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT, + ControlFile.system_identifier); + + printf(_("pg_control version number: %u\n"), + ControlFile.pg_control_version); + printf(_("Catalog version number: %u\n"), + ControlFile.catalog_version_no); + printf(_("Database system identifier: %s\n"), + sysident_str); + printf(_("Latest checkpoint's TimeLineID: %u\n"), + ControlFile.checkPointCopy.ThisTimeLineID); + printf(_("Latest checkpoint's full_page_writes: %s\n"), + ControlFile.checkPointCopy.fullPageWrites ? _("on") : _("off")); + printf(_("Latest checkpoint's NextXID: %u:%u\n"), + ControlFile.checkPointCopy.nextXidEpoch, + ControlFile.checkPointCopy.nextXid); + printf(_("Latest checkpoint's NextOID: %u\n"), + ControlFile.checkPointCopy.nextOid); + printf(_("Latest checkpoint's NextMultiXactId: %u\n"), + ControlFile.checkPointCopy.nextMulti); + printf(_("Latest checkpoint's NextMultiOffset: %u\n"), + ControlFile.checkPointCopy.nextMultiOffset); + printf(_("Latest checkpoint's oldestXID: %u\n"), + ControlFile.checkPointCopy.oldestXid); + printf(_("Latest checkpoint's oldestXID's DB: %u\n"), + ControlFile.checkPointCopy.oldestXidDB); + printf(_("Latest checkpoint's oldestActiveXID: %u\n"), + ControlFile.checkPointCopy.oldestActiveXid); + printf(_("Latest checkpoint's oldestMultiXid: %u\n"), + ControlFile.checkPointCopy.oldestMulti); + printf(_("Latest checkpoint's oldestMulti's DB: %u\n"), + ControlFile.checkPointCopy.oldestMultiDB); + printf(_("Latest checkpoint's oldestCommitTsXid:%u\n"), + ControlFile.checkPointCopy.oldestCommitTsXid); + printf(_("Latest checkpoint's newestCommitTsXid:%u\n"), + ControlFile.checkPointCopy.newestCommitTsXid); + printf(_("Maximum data alignment: %u\n"), + ControlFile.maxAlign); + /* we don't print floatFormat since can't say much useful about it */ + printf(_("Database block size: %u\n"), + ControlFile.blcksz); + printf(_("Blocks per segment of large relation: %u\n"), + ControlFile.relseg_size); + printf(_("WAL block size: %u\n"), + ControlFile.xlog_blcksz); + printf(_("Bytes per WAL segment: %u\n"), + ControlFile.xlog_seg_size); + printf(_("Maximum length of identifiers: %u\n"), + ControlFile.nameDataLen); + printf(_("Maximum columns in an index: %u\n"), + ControlFile.indexMaxKeys); + printf(_("Maximum size of a TOAST chunk: %u\n"), + ControlFile.toast_max_chunk_size); + printf(_("Size of a large-object chunk: %u\n"), + ControlFile.loblksize); + printf(_("Date/time type storage: %s\n"), + (ControlFile.enableIntTimes ? _("64-bit integers") : _("floating-point numbers"))); + printf(_("Float4 argument passing: %s\n"), + (ControlFile.float4ByVal ? _("by value") : _("by reference"))); + printf(_("Float8 argument passing: %s\n"), + (ControlFile.float8ByVal ? _("by value") : _("by reference"))); + printf(_("Data page checksum version: %u\n"), + ControlFile.data_checksum_version); +} + + +/* + * Print the values to be changed. + */ +static void +PrintNewControlValues(void) +{ + char fname[MAXFNAMELEN]; + + /* This will be always printed in order to keep format same. */ + printf(_("\n\nValues to be changed:\n\n")); + + XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo); + printf(_("First log segment after reset: %s\n"), fname); + + if (set_mxid != 0) + { + printf(_("NextMultiXactId: %u\n"), + ControlFile.checkPointCopy.nextMulti); + printf(_("OldestMultiXid: %u\n"), + ControlFile.checkPointCopy.oldestMulti); + printf(_("OldestMulti's DB: %u\n"), + ControlFile.checkPointCopy.oldestMultiDB); + } + + if (set_mxoff != -1) + { + printf(_("NextMultiOffset: %u\n"), + ControlFile.checkPointCopy.nextMultiOffset); + } + + if (set_oid != 0) + { + printf(_("NextOID: %u\n"), + ControlFile.checkPointCopy.nextOid); + } + + if (set_xid != 0) + { + printf(_("NextXID: %u\n"), + ControlFile.checkPointCopy.nextXid); + printf(_("OldestXID: %u\n"), + ControlFile.checkPointCopy.oldestXid); + printf(_("OldestXID's DB: %u\n"), + ControlFile.checkPointCopy.oldestXidDB); + } + + if (set_xid_epoch != -1) + { + printf(_("NextXID epoch: %u\n"), + ControlFile.checkPointCopy.nextXidEpoch); + } + + if (set_oldest_commit_ts_xid != 0) + { + printf(_("oldestCommitTsXid: %u\n"), + ControlFile.checkPointCopy.oldestCommitTsXid); + } + if (set_newest_commit_ts_xid != 0) + { + printf(_("newestCommitTsXid: %u\n"), + ControlFile.checkPointCopy.newestCommitTsXid); + } +} + + +/* + * Write out the new pg_control file. + */ +static void +RewriteControlFile(void) +{ + int fd; + char buffer[PG_CONTROL_SIZE]; /* need not be aligned */ + + /* + * Adjust fields as needed to force an empty XLOG starting at + * newXlogSegNo. + */ + XLogSegNoOffsetToRecPtr(newXlogSegNo, SizeOfXLogLongPHD, + ControlFile.checkPointCopy.redo); + ControlFile.checkPointCopy.time = (pg_time_t) time(NULL); + + ControlFile.state = DB_SHUTDOWNED; + ControlFile.time = (pg_time_t) time(NULL); + ControlFile.checkPoint = ControlFile.checkPointCopy.redo; + ControlFile.prevCheckPoint = 0; + ControlFile.minRecoveryPoint = 0; + ControlFile.minRecoveryPointTLI = 0; + ControlFile.backupStartPoint = 0; + ControlFile.backupEndPoint = 0; + ControlFile.backupEndRequired = false; + + /* + * Force the defaults for max_* settings. The values don't really matter + * as long as wal_level='minimal'; the postmaster will reset these fields + * anyway at startup. + */ + ControlFile.wal_level = WAL_LEVEL_MINIMAL; + ControlFile.wal_log_hints = false; + ControlFile.track_commit_timestamp = false; + ControlFile.MaxConnections = 100; + ControlFile.max_worker_processes = 8; + ControlFile.max_prepared_xacts = 0; + ControlFile.max_locks_per_xact = 64; + + /* Now we can force the recorded xlog seg size to the right thing. */ + ControlFile.xlog_seg_size = XLogSegSize; + + /* Contents are protected with a CRC */ + INIT_CRC32C(ControlFile.crc); + COMP_CRC32C(ControlFile.crc, + (char *) &ControlFile, + offsetof(ControlFileData, crc)); + FIN_CRC32C(ControlFile.crc); + + /* + * We write out PG_CONTROL_SIZE bytes into pg_control, zero-padding the + * excess over sizeof(ControlFileData). This reduces the odds of + * premature-EOF errors when reading pg_control. We'll still fail when we + * check the contents of the file, but hopefully with a more specific + * error than "couldn't read pg_control". + */ + if (sizeof(ControlFileData) > PG_CONTROL_SIZE) + { + fprintf(stderr, + _("%s: internal error -- sizeof(ControlFileData) is too large ... fix PG_CONTROL_SIZE\n"), + progname); + exit(1); + } + + memset(buffer, 0, PG_CONTROL_SIZE); + memcpy(buffer, &ControlFile, sizeof(ControlFileData)); + + unlink(XLOG_CONTROL_FILE); + + fd = open(XLOG_CONTROL_FILE, + O_RDWR | O_CREAT | O_EXCL | PG_BINARY, + S_IRUSR | S_IWUSR); + if (fd < 0) + { + fprintf(stderr, _("%s: could not create pg_control file: %s\n"), + progname, strerror(errno)); + exit(1); + } + + errno = 0; + if (write(fd, buffer, PG_CONTROL_SIZE) != PG_CONTROL_SIZE) + { + /* if write didn't set errno, assume problem is no disk space */ + if (errno == 0) + errno = ENOSPC; + fprintf(stderr, _("%s: could not write pg_control file: %s\n"), + progname, strerror(errno)); + exit(1); + } + + if (fsync(fd) != 0) + { + fprintf(stderr, _("%s: fsync error: %s\n"), progname, strerror(errno)); + exit(1); + } + + close(fd); +} + + +/* + * Scan existing XLOG files and determine the highest existing WAL address + * + * On entry, ControlFile.checkPointCopy.redo and ControlFile.xlog_seg_size + * are assumed valid (note that we allow the old xlog seg size to differ + * from what we're using). On exit, newXlogId and newXlogSeg are set to + * suitable values for the beginning of replacement WAL (in our seg size). + */ +static void +FindEndOfXLOG(void) +{ + DIR *xldir; + struct dirent *xlde; + uint64 segs_per_xlogid; + uint64 xlogbytepos; + + /* + * Initialize the max() computation using the last checkpoint address from + * old pg_control. Note that for the moment we are working with segment + * numbering according to the old xlog seg size. + */ + segs_per_xlogid = (UINT64CONST(0x0000000100000000) / ControlFile.xlog_seg_size); + newXlogSegNo = ControlFile.checkPointCopy.redo / ControlFile.xlog_seg_size; + + /* + * Scan the pg_wal directory to find existing WAL segment files. We + * assume any present have been used; in most scenarios this should be + * conservative, because of xlog.c's attempts to pre-create files. + */ + xldir = opendir(XLOGDIR); + if (xldir == NULL) + { + fprintf(stderr, _("%s: could not open directory \"%s\": %s\n"), + progname, XLOGDIR, strerror(errno)); + exit(1); + } + + while (errno = 0, (xlde = readdir(xldir)) != NULL) + { + if (IsXLogFileName(xlde->d_name) || + IsPartialXLogFileName(xlde->d_name)) + { + unsigned int tli, + log, + seg; + XLogSegNo segno; + + /* + * Note: We don't use XLogFromFileName here, because we want to + * use the segment size from the control file, not the size the + * pg_resetwal binary was compiled with + */ + sscanf(xlde->d_name, "%08X%08X%08X", &tli, &log, &seg); + segno = ((uint64) log) * segs_per_xlogid + seg; + + /* + * Note: we take the max of all files found, regardless of their + * timelines. Another possibility would be to ignore files of + * timelines other than the target TLI, but this seems safer. + * Better too large a result than too small... + */ + if (segno > newXlogSegNo) + newXlogSegNo = segno; + } + } + + if (errno) + { + fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"), + progname, XLOGDIR, strerror(errno)); + exit(1); + } + + if (closedir(xldir)) + { + fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"), + progname, XLOGDIR, strerror(errno)); + exit(1); + } + + /* + * Finally, convert to new xlog seg size, and advance by one to ensure we + * are in virgin territory. + */ + xlogbytepos = newXlogSegNo * ControlFile.xlog_seg_size; + newXlogSegNo = (xlogbytepos + XLogSegSize - 1) / XLogSegSize; + newXlogSegNo++; +} + + +/* + * Remove existing XLOG files + */ +static void +KillExistingXLOG(void) +{ + DIR *xldir; + struct dirent *xlde; + char path[MAXPGPATH]; + + xldir = opendir(XLOGDIR); + if (xldir == NULL) + { + fprintf(stderr, _("%s: could not open directory \"%s\": %s\n"), + progname, XLOGDIR, strerror(errno)); + exit(1); + } + + while (errno = 0, (xlde = readdir(xldir)) != NULL) + { + if (IsXLogFileName(xlde->d_name) || + IsPartialXLogFileName(xlde->d_name)) + { + snprintf(path, MAXPGPATH, "%s/%s", XLOGDIR, xlde->d_name); + if (unlink(path) < 0) + { + fprintf(stderr, _("%s: could not delete file \"%s\": %s\n"), + progname, path, strerror(errno)); + exit(1); + } + } + } + + if (errno) + { + fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"), + progname, XLOGDIR, strerror(errno)); + exit(1); + } + + if (closedir(xldir)) + { + fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"), + progname, XLOGDIR, strerror(errno)); + exit(1); + } +} + + +/* + * Remove existing archive status files + */ +static void +KillExistingArchiveStatus(void) +{ + DIR *xldir; + struct dirent *xlde; + char path[MAXPGPATH]; + +#define ARCHSTATDIR XLOGDIR "/archive_status" + + xldir = opendir(ARCHSTATDIR); + if (xldir == NULL) + { + fprintf(stderr, _("%s: could not open directory \"%s\": %s\n"), + progname, ARCHSTATDIR, strerror(errno)); + exit(1); + } + + while (errno = 0, (xlde = readdir(xldir)) != NULL) + { + if (strspn(xlde->d_name, "0123456789ABCDEF") == XLOG_FNAME_LEN && + (strcmp(xlde->d_name + XLOG_FNAME_LEN, ".ready") == 0 || + strcmp(xlde->d_name + XLOG_FNAME_LEN, ".done") == 0 || + strcmp(xlde->d_name + XLOG_FNAME_LEN, ".partial.ready") == 0 || + strcmp(xlde->d_name + XLOG_FNAME_LEN, ".partial.done") == 0)) + { + snprintf(path, MAXPGPATH, "%s/%s", ARCHSTATDIR, xlde->d_name); + if (unlink(path) < 0) + { + fprintf(stderr, _("%s: could not delete file \"%s\": %s\n"), + progname, path, strerror(errno)); + exit(1); + } + } + } + + if (errno) + { + fprintf(stderr, _("%s: could not read directory \"%s\": %s\n"), + progname, ARCHSTATDIR, strerror(errno)); + exit(1); + } + + if (closedir(xldir)) + { + fprintf(stderr, _("%s: could not close directory \"%s\": %s\n"), + progname, ARCHSTATDIR, strerror(errno)); + exit(1); + } +} + + +/* + * Write an empty XLOG file, containing only the checkpoint record + * already set up in ControlFile. + */ +static void +WriteEmptyXLOG(void) +{ + char *buffer; + XLogPageHeader page; + XLogLongPageHeader longpage; + XLogRecord *record; + pg_crc32c crc; + char path[MAXPGPATH]; + int fd; + int nbytes; + char *recptr; + + /* Use malloc() to ensure buffer is MAXALIGNED */ + buffer = (char *) pg_malloc(XLOG_BLCKSZ); + page = (XLogPageHeader) buffer; + memset(buffer, 0, XLOG_BLCKSZ); + + /* Set up the XLOG page header */ + page->xlp_magic = XLOG_PAGE_MAGIC; + page->xlp_info = XLP_LONG_HEADER; + page->xlp_tli = ControlFile.checkPointCopy.ThisTimeLineID; + page->xlp_pageaddr = ControlFile.checkPointCopy.redo - SizeOfXLogLongPHD; + longpage = (XLogLongPageHeader) page; + longpage->xlp_sysid = ControlFile.system_identifier; + longpage->xlp_seg_size = XLogSegSize; + longpage->xlp_xlog_blcksz = XLOG_BLCKSZ; + + /* Insert the initial checkpoint record */ + recptr = (char *) page + SizeOfXLogLongPHD; + record = (XLogRecord *) recptr; + record->xl_prev = 0; + record->xl_xid = InvalidTransactionId; + record->xl_tot_len = SizeOfXLogRecord + SizeOfXLogRecordDataHeaderShort + sizeof(CheckPoint); + record->xl_info = XLOG_CHECKPOINT_SHUTDOWN; + record->xl_rmid = RM_XLOG_ID; + + recptr += SizeOfXLogRecord; + *(recptr++) = XLR_BLOCK_ID_DATA_SHORT; + *(recptr++) = sizeof(CheckPoint); + memcpy(recptr, &ControlFile.checkPointCopy, + sizeof(CheckPoint)); + + INIT_CRC32C(crc); + COMP_CRC32C(crc, ((char *) record) + SizeOfXLogRecord, record->xl_tot_len - SizeOfXLogRecord); + COMP_CRC32C(crc, (char *) record, offsetof(XLogRecord, xl_crc)); + FIN_CRC32C(crc); + record->xl_crc = crc; + + /* Write the first page */ + XLogFilePath(path, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo); + + unlink(path); + + fd = open(path, O_RDWR | O_CREAT | O_EXCL | PG_BINARY, + S_IRUSR | S_IWUSR); + if (fd < 0) + { + fprintf(stderr, _("%s: could not open file \"%s\": %s\n"), + progname, path, strerror(errno)); + exit(1); + } + + errno = 0; + if (write(fd, buffer, XLOG_BLCKSZ) != XLOG_BLCKSZ) + { + /* if write didn't set errno, assume problem is no disk space */ + if (errno == 0) + errno = ENOSPC; + fprintf(stderr, _("%s: could not write file \"%s\": %s\n"), + progname, path, strerror(errno)); + exit(1); + } + + /* Fill the rest of the file with zeroes */ + memset(buffer, 0, XLOG_BLCKSZ); + for (nbytes = XLOG_BLCKSZ; nbytes < XLogSegSize; nbytes += XLOG_BLCKSZ) + { + errno = 0; + if (write(fd, buffer, XLOG_BLCKSZ) != XLOG_BLCKSZ) + { + if (errno == 0) + errno = ENOSPC; + fprintf(stderr, _("%s: could not write file \"%s\": %s\n"), + progname, path, strerror(errno)); + exit(1); + } + } + + if (fsync(fd) != 0) + { + fprintf(stderr, _("%s: fsync error: %s\n"), progname, strerror(errno)); + exit(1); + } + + close(fd); +} + + +static void +usage(void) +{ + printf(_("%s resets the PostgreSQL transaction log.\n\n"), progname); + printf(_("Usage:\n %s [OPTION]... DATADIR\n\n"), progname); + printf(_("Options:\n")); + printf(_(" -c XID,XID set oldest and newest transactions bearing commit timestamp\n")); + printf(_(" (zero in either value means no change)\n")); + printf(_(" [-D] DATADIR data directory\n")); + printf(_(" -e XIDEPOCH set next transaction ID epoch\n")); + printf(_(" -f force update to be done\n")); + printf(_(" -l XLOGFILE force minimum WAL starting location for new transaction log\n")); + printf(_(" -m MXID,MXID set next and oldest multitransaction ID\n")); + printf(_(" -n no update, just show what would be done (for testing)\n")); + printf(_(" -o OID set next OID\n")); + printf(_(" -O OFFSET set next multitransaction offset\n")); + printf(_(" -V, --version output version information, then exit\n")); + printf(_(" -x XID set next transaction ID\n")); + printf(_(" -?, --help show this help, then exit\n")); + printf(_("\nReport bugs to <pgsql-bugs@postgresql.org>.\n")); +} |