Consistently use "superuser" instead of "super user"

[pgsql.git] / src / bin / pg_basebackup / pg_basebackup.c

/*-------------------------------------------------------------------------
 *
 * pg_basebackup.c - receive a base backup using streaming replication protocol
 *
 * Author: Magnus Hagander <magnus@hagander.net>
 *
 * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
 *                src/bin/pg_basebackup/pg_basebackup.c
 *-------------------------------------------------------------------------
 */

#include "postgres_fe.h"

#include <unistd.h>
#include <dirent.h>
#include <limits.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <signal.h>
#include <time.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#ifdef HAVE_LIBZ
#include <zlib.h>
#endif

#include "access/xlog_internal.h"
#include "common/file_perm.h"
#include "common/file_utils.h"
#include "common/logging.h"
#include "common/string.h"
#include "fe_utils/option_utils.h"
#include "fe_utils/recovery_gen.h"
#include "fe_utils/string_utils.h"
#include "getopt_long.h"
#include "libpq-fe.h"
#include "pgtar.h"
#include "pgtime.h"
#include "pqexpbuffer.h"
#include "receivelog.h"
#include "replication/basebackup.h"
#include "streamutil.h"

#define ERRCODE_DATA_CORRUPTED  "XX001"

typedef struct TablespaceListCell
{
        struct TablespaceListCell *next;
        char            old_dir[MAXPGPATH];
        char            new_dir[MAXPGPATH];
} TablespaceListCell;

typedef struct TablespaceList
{
        TablespaceListCell *head;
        TablespaceListCell *tail;
} TablespaceList;

typedef struct WriteTarState
{
        int                     tablespacenum;
        char            filename[MAXPGPATH];
        FILE       *tarfile;
        char            tarhdr[TAR_BLOCK_SIZE];
        bool            basetablespace;
        bool            in_tarhdr;
        bool            skip_file;
        bool            is_recovery_guc_supported;
        bool            is_postgresql_auto_conf;
        bool            found_postgresql_auto_conf;
        int                     file_padding_len;
        size_t          tarhdrsz;
        pgoff_t         filesz;
#ifdef HAVE_LIBZ
        gzFile          ztarfile;
#endif
} WriteTarState;

typedef struct UnpackTarState
{
        int                     tablespacenum;
        char            current_path[MAXPGPATH];
        char            filename[MAXPGPATH];
        const char *mapped_tblspc_path;
        pgoff_t         current_len_left;
        int                     current_padding;
        FILE       *file;
} UnpackTarState;

typedef struct WriteManifestState
{
        char            filename[MAXPGPATH];
        FILE       *file;
} WriteManifestState;

typedef void (*WriteDataCallback) (size_t nbytes, char *buf,
                                                                   void *callback_data);

/*
 * pg_xlog has been renamed to pg_wal in version 10.  This version number
 * should be compared with PQserverVersion().
 */
#define MINIMUM_VERSION_FOR_PG_WAL      100000

/*
 * Temporary replication slots are supported from version 10.
 */
#define MINIMUM_VERSION_FOR_TEMP_SLOTS 100000

/*
 * Backup manifests are supported from version 13.
 */
#define MINIMUM_VERSION_FOR_MANIFESTS   130000

/*
 * Different ways to include WAL
 */
typedef enum
{
        NO_WAL,
        FETCH_WAL,
        STREAM_WAL
} IncludeWal;

/* Global options */
static char *basedir = NULL;
static TablespaceList tablespace_dirs = {NULL, NULL};
static char *xlog_dir = NULL;
static char format = 'p';               /* p(lain)/t(ar) */
static char *label = "pg_basebackup base backup";
static bool noclean = false;
static bool checksum_failure = false;
static bool showprogress = false;
static bool estimatesize = true;
static int      verbose = 0;
static int      compresslevel = 0;
static IncludeWal includewal = STREAM_WAL;
static bool fastcheckpoint = false;
static bool writerecoveryconf = false;
static bool do_sync = true;
static int      standby_message_timeout = 10 * 1000;    /* 10 sec = default */
static pg_time_t last_progress_report = 0;
static int32 maxrate = 0;               /* no limit by default */
static char *replication_slot = NULL;
static bool temp_replication_slot = true;
static bool create_slot = false;
static bool no_slot = false;
static bool verify_checksums = true;
static bool manifest = true;
static bool manifest_force_encode = false;
static char *manifest_checksums = NULL;

static bool success = false;
static bool made_new_pgdata = false;
static bool found_existing_pgdata = false;
static bool made_new_xlogdir = false;
static bool found_existing_xlogdir = false;
static bool made_tablespace_dirs = false;
static bool found_tablespace_dirs = false;

/* Progress counters */
static uint64 totalsize_kb;
static uint64 totaldone;
static int      tablespacecount;

/* Pipe to communicate with background wal receiver process */
#ifndef WIN32
static int      bgpipe[2] = {-1, -1};
#endif

/* Handle to child process */
static pid_t bgchild = -1;
static bool in_log_streamer = false;

/* End position for xlog streaming, empty string if unknown yet */
static XLogRecPtr xlogendptr;

#ifndef WIN32
static int      has_xlogendptr = 0;
#else
static volatile LONG has_xlogendptr = 0;
#endif

/* Contents of configuration file to be generated */
static PQExpBuffer recoveryconfcontents = NULL;

/* Function headers */
static void usage(void);
static void verify_dir_is_empty_or_create(char *dirname, bool *created, bool *found);
static void progress_report(int tablespacenum, const char *filename, bool force,
                                                        bool finished);

static void ReceiveTarFile(PGconn *conn, PGresult *res, int rownum);
static void ReceiveTarCopyChunk(size_t r, char *copybuf, void *callback_data);
static void ReceiveAndUnpackTarFile(PGconn *conn, PGresult *res, int rownum);
static void ReceiveTarAndUnpackCopyChunk(size_t r, char *copybuf,
                                                                                 void *callback_data);
static void ReceiveBackupManifest(PGconn *conn);
static void ReceiveBackupManifestChunk(size_t r, char *copybuf,
                                                                           void *callback_data);
static void ReceiveBackupManifestInMemory(PGconn *conn, PQExpBuffer buf);
static void ReceiveBackupManifestInMemoryChunk(size_t r, char *copybuf,
                                                                                           void *callback_data);
static void BaseBackup(void);

static bool reached_end_position(XLogRecPtr segendpos, uint32 timeline,
                                                                 bool segment_finished);

static const char *get_tablespace_mapping(const char *dir);
static void tablespace_list_append(const char *arg);


static void
cleanup_directories_atexit(void)
{
        if (success || in_log_streamer)
                return;

        if (!noclean && !checksum_failure)
        {
                if (made_new_pgdata)
                {
                        pg_log_info("removing data directory \"%s\"", basedir);
                        if (!rmtree(basedir, true))
                                pg_log_error("failed to remove data directory");
                }
                else if (found_existing_pgdata)
                {
                        pg_log_info("removing contents of data directory \"%s\"", basedir);
                        if (!rmtree(basedir, false))
                                pg_log_error("failed to remove contents of data directory");
                }

                if (made_new_xlogdir)
                {
                        pg_log_info("removing WAL directory \"%s\"", xlog_dir);
                        if (!rmtree(xlog_dir, true))
                                pg_log_error("failed to remove WAL directory");
                }
                else if (found_existing_xlogdir)
                {
                        pg_log_info("removing contents of WAL directory \"%s\"", xlog_dir);
                        if (!rmtree(xlog_dir, false))
                                pg_log_error("failed to remove contents of WAL directory");
                }
        }
        else
        {
                if ((made_new_pgdata || found_existing_pgdata) && !checksum_failure)
                        pg_log_info("data directory \"%s\" not removed at user's request", basedir);

                if (made_new_xlogdir || found_existing_xlogdir)
                        pg_log_info("WAL directory \"%s\" not removed at user's request", xlog_dir);
        }

        if ((made_tablespace_dirs || found_tablespace_dirs) && !checksum_failure)
                pg_log_info("changes to tablespace directories will not be undone");
}

static void
disconnect_atexit(void)
{
        if (conn != NULL)
                PQfinish(conn);
}

#ifndef WIN32
/*
 * On windows, our background thread dies along with the process. But on
 * Unix, if we have started a subprocess, we want to kill it off so it
 * doesn't remain running trying to stream data.
 */
static void
kill_bgchild_atexit(void)
{
        if (bgchild > 0)
                kill(bgchild, SIGTERM);
}
#endif

/*
 * Split argument into old_dir and new_dir and append to tablespace mapping
 * list.
 */
static void
tablespace_list_append(const char *arg)
{
        TablespaceListCell *cell = (TablespaceListCell *) pg_malloc0(sizeof(TablespaceListCell));
        char       *dst;
        char       *dst_ptr;
        const char *arg_ptr;

        dst_ptr = dst = cell->old_dir;
        for (arg_ptr = arg; *arg_ptr; arg_ptr++)
        {
                if (dst_ptr - dst >= MAXPGPATH)
                {
                        pg_log_error("directory name too long");
                        exit(1);
                }

                if (*arg_ptr == '\\' && *(arg_ptr + 1) == '=')
                        ;                                       /* skip backslash escaping = */
                else if (*arg_ptr == '=' && (arg_ptr == arg || *(arg_ptr - 1) != '\\'))
                {
                        if (*cell->new_dir)
                        {
                                pg_log_error("multiple \"=\" signs in tablespace mapping");
                                exit(1);
                        }
                        else
                                dst = dst_ptr = cell->new_dir;
                }
                else
                        *dst_ptr++ = *arg_ptr;
        }

        if (!*cell->old_dir || !*cell->new_dir)
        {
                pg_log_error("invalid tablespace mapping format \"%s\", must be \"OLDDIR=NEWDIR\"", arg);
                exit(1);
        }

        /*
         * This check isn't absolutely necessary.  But all tablespaces are created
         * with absolute directories, so specifying a non-absolute path here would
         * just never match, possibly confusing users.  It's also good to be
         * consistent with the new_dir check.
         */
        if (!is_absolute_path(cell->old_dir))
        {
                pg_log_error("old directory is not an absolute path in tablespace mapping: %s",
                                         cell->old_dir);
                exit(1);
        }

        if (!is_absolute_path(cell->new_dir))
        {
                pg_log_error("new directory is not an absolute path in tablespace mapping: %s",
                                         cell->new_dir);
                exit(1);
        }

        /*
         * Comparisons done with these values should involve similarly
         * canonicalized path values.  This is particularly sensitive on Windows
         * where path values may not necessarily use Unix slashes.
         */
        canonicalize_path(cell->old_dir);
        canonicalize_path(cell->new_dir);

        if (tablespace_dirs.tail)
                tablespace_dirs.tail->next = cell;
        else
                tablespace_dirs.head = cell;
        tablespace_dirs.tail = cell;
}


#ifdef HAVE_LIBZ
static const char *
get_gz_error(gzFile gzf)
{
        int                     errnum;
        const char *errmsg;

        errmsg = gzerror(gzf, &errnum);
        if (errnum == Z_ERRNO)
                return strerror(errno);
        else
                return errmsg;
}
#endif

static void
usage(void)
{
        printf(_("%s takes a base backup of a running PostgreSQL server.\n\n"),
                   progname);
        printf(_("Usage:\n"));
        printf(_("  %s [OPTION]...\n"), progname);
        printf(_("\nOptions controlling the output:\n"));
        printf(_("  -D, --pgdata=DIRECTORY receive base backup into directory\n"));
        printf(_("  -F, --format=p|t       output format (plain (default), tar)\n"));
        printf(_("  -r, --max-rate=RATE    maximum transfer rate to transfer data directory\n"
                         "                         (in kB/s, or use suffix \"k\" or \"M\")\n"));
        printf(_("  -R, --write-recovery-conf\n"
                         "                         write configuration for replication\n"));
        printf(_("  -T, --tablespace-mapping=OLDDIR=NEWDIR\n"
                         "                         relocate tablespace in OLDDIR to NEWDIR\n"));
        printf(_("      --waldir=WALDIR    location for the write-ahead log directory\n"));
        printf(_("  -X, --wal-method=none|fetch|stream\n"
                         "                         include required WAL files with specified method\n"));
        printf(_("  -z, --gzip             compress tar output\n"));
        printf(_("  -Z, --compress=0-9     compress tar output with given compression level\n"));
        printf(_("\nGeneral options:\n"));
        printf(_("  -c, --checkpoint=fast|spread\n"
                         "                         set fast or spread checkpointing\n"));
        printf(_("  -C, --create-slot      create replication slot\n"));
        printf(_("  -l, --label=LABEL      set backup label\n"));
        printf(_("  -n, --no-clean         do not clean up after errors\n"));
        printf(_("  -N, --no-sync          do not wait for changes to be written safely to disk\n"));
        printf(_("  -P, --progress         show progress information\n"));
        printf(_("  -S, --slot=SLOTNAME    replication slot to use\n"));
        printf(_("  -v, --verbose          output verbose messages\n"));
        printf(_("  -V, --version          output version information, then exit\n"));
        printf(_("      --manifest-checksums=SHA{224,256,384,512}|CRC32C|NONE\n"
                         "                         use algorithm for manifest checksums\n"));
        printf(_("      --manifest-force-encode\n"
                         "                         hex encode all file names in manifest\n"));
        printf(_("      --no-estimate-size do not estimate backup size in server side\n"));
        printf(_("      --no-manifest      suppress generation of backup manifest\n"));
        printf(_("      --no-slot          prevent creation of temporary replication slot\n"));
        printf(_("      --no-verify-checksums\n"
                         "                         do not verify checksums\n"));
        printf(_("  -?, --help             show this help, then exit\n"));
        printf(_("\nConnection options:\n"));
        printf(_("  -d, --dbname=CONNSTR   connection string\n"));
        printf(_("  -h, --host=HOSTNAME    database server host or socket directory\n"));
        printf(_("  -p, --port=PORT        database server port number\n"));
        printf(_("  -s, --status-interval=INTERVAL\n"
                         "                         time between status packets sent to server (in seconds)\n"));
        printf(_("  -U, --username=NAME    connect as specified database user\n"));
        printf(_("  -w, --no-password      never prompt for password\n"));
        printf(_("  -W, --password         force password prompt (should happen automatically)\n"));
        printf(_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
        printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
}


/*
 * Called in the background process every time data is received.
 * On Unix, we check to see if there is any data on our pipe
 * (which would mean we have a stop position), and if it is, check if
 * it is time to stop.
 * On Windows, we are in a single process, so we can just check if it's
 * time to stop.
 */
static bool
reached_end_position(XLogRecPtr segendpos, uint32 timeline,
                                         bool segment_finished)
{
        if (!has_xlogendptr)
        {
#ifndef WIN32
                fd_set          fds;
                struct timeval tv;
                int                     r;

                /*
                 * Don't have the end pointer yet - check our pipe to see if it has
                 * been sent yet.
                 */
                FD_ZERO(&fds);
                FD_SET(bgpipe[0], &fds);

                MemSet(&tv, 0, sizeof(tv));

                r = select(bgpipe[0] + 1, &fds, NULL, NULL, &tv);
                if (r == 1)
                {
                        char            xlogend[64];
                        uint32          hi,
                                                lo;

                        MemSet(xlogend, 0, sizeof(xlogend));
                        r = read(bgpipe[0], xlogend, sizeof(xlogend) - 1);
                        if (r < 0)
                        {
                                pg_log_error("could not read from ready pipe: %m");
                                exit(1);
                        }

                        if (sscanf(xlogend, "%X/%X", &hi, &lo) != 2)
                        {
                                pg_log_error("could not parse write-ahead log location \"%s\"",
                                                         xlogend);
                                exit(1);
                        }
                        xlogendptr = ((uint64) hi) << 32 | lo;
                        has_xlogendptr = 1;

                        /*
                         * Fall through to check if we've reached the point further
                         * already.
                         */
                }
                else
                {
                        /*
                         * No data received on the pipe means we don't know the end
                         * position yet - so just say it's not time to stop yet.
                         */
                        return false;
                }
#else

                /*
                 * On win32, has_xlogendptr is set by the main thread, so if it's not
                 * set here, we just go back and wait until it shows up.
                 */
                return false;
#endif
        }

        /*
         * At this point we have an end pointer, so compare it to the current
         * position to figure out if it's time to stop.
         */
        if (segendpos >= xlogendptr)
                return true;

        /*
         * Have end pointer, but haven't reached it yet - so tell the caller to
         * keep streaming.
         */
        return false;
}

typedef struct
{
        PGconn     *bgconn;
        XLogRecPtr      startptr;
        char            xlog[MAXPGPATH];        /* directory or tarfile depending on mode */
        char       *sysidentifier;
        int                     timeline;
} logstreamer_param;

static int
LogStreamerMain(logstreamer_param *param)
{
        StreamCtl       stream;

        in_log_streamer = true;

        MemSet(&stream, 0, sizeof(stream));
        stream.startpos = param->startptr;
        stream.timeline = param->timeline;
        stream.sysidentifier = param->sysidentifier;
        stream.stream_stop = reached_end_position;
#ifndef WIN32
        stream.stop_socket = bgpipe[0];
#else
        stream.stop_socket = PGINVALID_SOCKET;
#endif
        stream.standby_message_timeout = standby_message_timeout;
        stream.synchronous = false;
        /* fsync happens at the end of pg_basebackup for all data */
        stream.do_sync = false;
        stream.mark_done = true;
        stream.partial_suffix = NULL;
        stream.replication_slot = replication_slot;

        if (format == 'p')
                stream.walmethod = CreateWalDirectoryMethod(param->xlog, 0,
                                                                                                        stream.do_sync);
        else
                stream.walmethod = CreateWalTarMethod(param->xlog, compresslevel,
                                                                                          stream.do_sync);

        if (!ReceiveXlogStream(param->bgconn, &stream))

                /*
                 * Any errors will already have been reported in the function process,
                 * but we need to tell the parent that we didn't shutdown in a nice
                 * way.
                 */
                return 1;

        if (!stream.walmethod->finish())
        {
                pg_log_error("could not finish writing WAL files: %m");
                return 1;
        }

        PQfinish(param->bgconn);

        if (format == 'p')
                FreeWalDirectoryMethod();
        else
                FreeWalTarMethod();
        pg_free(stream.walmethod);

        return 0;
}

/*
 * Initiate background process for receiving xlog during the backup.
 * The background stream will use its own database connection so we can
 * stream the logfile in parallel with the backups.
 */
static void
StartLogStreamer(char *startpos, uint32 timeline, char *sysidentifier)
{
        logstreamer_param *param;
        uint32          hi,
                                lo;
        char            statusdir[MAXPGPATH];

        param = pg_malloc0(sizeof(logstreamer_param));
        param->timeline = timeline;
        param->sysidentifier = sysidentifier;

        /* Convert the starting position */
        if (sscanf(startpos, "%X/%X", &hi, &lo) != 2)
        {
                pg_log_error("could not parse write-ahead log location \"%s\"",
                                         startpos);
                exit(1);
        }
        param->startptr = ((uint64) hi) << 32 | lo;
        /* Round off to even segment position */
        param->startptr -= XLogSegmentOffset(param->startptr, WalSegSz);

#ifndef WIN32
        /* Create our background pipe */
        if (pipe(bgpipe) < 0)
        {
                pg_log_error("could not create pipe for background process: %m");
                exit(1);
        }
#endif

        /* Get a second connection */
        param->bgconn = GetConnection();
        if (!param->bgconn)
                /* Error message already written in GetConnection() */
                exit(1);

        /* In post-10 cluster, pg_xlog has been renamed to pg_wal */
        snprintf(param->xlog, sizeof(param->xlog), "%s/%s",
                         basedir,
                         PQserverVersion(conn) < MINIMUM_VERSION_FOR_PG_WAL ?
                         "pg_xlog" : "pg_wal");

        /* Temporary replication slots are only supported in 10 and newer */
        if (PQserverVersion(conn) < MINIMUM_VERSION_FOR_TEMP_SLOTS)
                temp_replication_slot = false;

        /*
         * Create replication slot if requested
         */
        if (temp_replication_slot && !replication_slot)
                replication_slot = psprintf("pg_basebackup_%d", (int) PQbackendPID(param->bgconn));
        if (temp_replication_slot || create_slot)
        {
                if (!CreateReplicationSlot(param->bgconn, replication_slot, NULL,
                                                                   temp_replication_slot, true, true, false, false))
                        exit(1);

                if (verbose)
                {
                        if (temp_replication_slot)
                                pg_log_info("created temporary replication slot \"%s\"",
                                                        replication_slot);
                        else
                                pg_log_info("created replication slot \"%s\"",
                                                        replication_slot);
                }
        }

        if (format == 'p')
        {
                /*
                 * Create pg_wal/archive_status or pg_xlog/archive_status (and thus
                 * pg_wal or pg_xlog) depending on the target server so we can write
                 * to basedir/pg_wal or basedir/pg_xlog as the directory entry in the
                 * tar file may arrive later.
                 */
                snprintf(statusdir, sizeof(statusdir), "%s/%s/archive_status",
                                 basedir,
                                 PQserverVersion(conn) < MINIMUM_VERSION_FOR_PG_WAL ?
                                 "pg_xlog" : "pg_wal");

                if (pg_mkdir_p(statusdir, pg_dir_create_mode) != 0 && errno != EEXIST)
                {
                        pg_log_error("could not create directory \"%s\": %m", statusdir);
                        exit(1);
                }
        }

        /*
         * Start a child process and tell it to start streaming. On Unix, this is
         * a fork(). On Windows, we create a thread.
         */
#ifndef WIN32
        bgchild = fork();
        if (bgchild == 0)
        {
                /* in child process */
                exit(LogStreamerMain(param));
        }
        else if (bgchild < 0)
        {
                pg_log_error("could not create background process: %m");
                exit(1);
        }

        /*
         * Else we are in the parent process and all is well.
         */
        atexit(kill_bgchild_atexit);
#else                                                   /* WIN32 */
        bgchild = _beginthreadex(NULL, 0, (void *) LogStreamerMain, param, 0, NULL);
        if (bgchild == 0)
        {
                pg_log_error("could not create background thread: %m");
                exit(1);
        }
#endif
}

/*
 * Verify that the given directory exists and is empty. If it does not
 * exist, it is created. If it exists but is not empty, an error will
 * be given and the process ended.
 */
static void
verify_dir_is_empty_or_create(char *dirname, bool *created, bool *found)
{
        switch (pg_check_dir(dirname))
        {
                case 0:

                        /*
                         * Does not exist, so create
                         */
                        if (pg_mkdir_p(dirname, pg_dir_create_mode) == -1)
                        {
                                pg_log_error("could not create directory \"%s\": %m", dirname);
                                exit(1);
                        }
                        if (created)
                                *created = true;
                        return;
                case 1:

                        /*
                         * Exists, empty
                         */
                        if (found)
                                *found = true;
                        return;
                case 2:
                case 3:
                case 4:

                        /*
                         * Exists, not empty
                         */
                        pg_log_error("directory \"%s\" exists but is not empty", dirname);
                        exit(1);
                case -1:

                        /*
                         * Access problem
                         */
                        pg_log_error("could not access directory \"%s\": %m", dirname);
                        exit(1);
        }
}


/*
 * Print a progress report based on the global variables. If verbose output
 * is enabled, also print the current file name.
 *
 * Progress report is written at maximum once per second, unless the force
 * parameter is set to true.
 *
 * If finished is set to true, this is the last progress report. The cursor
 * is moved to the next line.
 */
static void
progress_report(int tablespacenum, const char *filename,
                                bool force, bool finished)
{
        int                     percent;
        char            totaldone_str[32];
        char            totalsize_str[32];
        pg_time_t       now;

        if (!showprogress)
                return;

        now = time(NULL);
        if (now == last_progress_report && !force && !finished)
                return;                                 /* Max once per second */

        last_progress_report = now;
        percent = totalsize_kb ? (int) ((totaldone / 1024) * 100 / totalsize_kb) : 0;

        /*
         * Avoid overflowing past 100% or the full size. This may make the total
         * size number change as we approach the end of the backup (the estimate
         * will always be wrong if WAL is included), but that's better than having
         * the done column be bigger than the total.
         */
        if (percent > 100)
                percent = 100;
        if (totaldone / 1024 > totalsize_kb)
                totalsize_kb = totaldone / 1024;

        /*
         * Separate step to keep platform-dependent format code out of
         * translatable strings.  And we only test for INT64_FORMAT availability
         * in snprintf, not fprintf.
         */
        snprintf(totaldone_str, sizeof(totaldone_str), INT64_FORMAT,
                         totaldone / 1024);
        snprintf(totalsize_str, sizeof(totalsize_str), INT64_FORMAT, totalsize_kb);

#define VERBOSE_FILENAME_LENGTH 35
        if (verbose)
        {
                if (!filename)

                        /*
                         * No filename given, so clear the status line (used for last
                         * call)
                         */
                        fprintf(stderr,
                                        ngettext("%*s/%s kB (100%%), %d/%d tablespace %*s",
                                                         "%*s/%s kB (100%%), %d/%d tablespaces %*s",
                                                         tablespacecount),
                                        (int) strlen(totalsize_str),
                                        totaldone_str, totalsize_str,
                                        tablespacenum, tablespacecount,
                                        VERBOSE_FILENAME_LENGTH + 5, "");
                else
                {
                        bool            truncate = (strlen(filename) > VERBOSE_FILENAME_LENGTH);

                        fprintf(stderr,
                                        ngettext("%*s/%s kB (%d%%), %d/%d tablespace (%s%-*.*s)",
                                                         "%*s/%s kB (%d%%), %d/%d tablespaces (%s%-*.*s)",
                                                         tablespacecount),
                                        (int) strlen(totalsize_str),
                                        totaldone_str, totalsize_str, percent,
                                        tablespacenum, tablespacecount,
                        /* Prefix with "..." if we do leading truncation */
                                        truncate ? "..." : "",
                                        truncate ? VERBOSE_FILENAME_LENGTH - 3 : VERBOSE_FILENAME_LENGTH,
                                        truncate ? VERBOSE_FILENAME_LENGTH - 3 : VERBOSE_FILENAME_LENGTH,
                        /* Truncate filename at beginning if it's too long */
                                        truncate ? filename + strlen(filename) - VERBOSE_FILENAME_LENGTH + 3 : filename);
                }
        }
        else
                fprintf(stderr,
                                ngettext("%*s/%s kB (%d%%), %d/%d tablespace",
                                                 "%*s/%s kB (%d%%), %d/%d tablespaces",
                                                 tablespacecount),
                                (int) strlen(totalsize_str),
                                totaldone_str, totalsize_str, percent,
                                tablespacenum, tablespacecount);

        /*
         * Stay on the same line if reporting to a terminal and we're not done
         * yet.
         */
        fputc((!finished && isatty(fileno(stderr))) ? '\r' : '\n', stderr);
}

static int32
parse_max_rate(char *src)
{
        double          result;
        char       *after_num;
        char       *suffix = NULL;

        errno = 0;
        result = strtod(src, &after_num);
        if (src == after_num)
        {
                pg_log_error("transfer rate \"%s\" is not a valid value", src);
                exit(1);
        }
        if (errno != 0)
        {
                pg_log_error("invalid transfer rate \"%s\": %m", src);
                exit(1);
        }

        if (result <= 0)
        {
                /*
                 * Reject obviously wrong values here.
                 */
                pg_log_error("transfer rate must be greater than zero");
                exit(1);
        }

        /*
         * Evaluate suffix, after skipping over possible whitespace. Lack of
         * suffix means kilobytes.
         */
        while (*after_num != '\0' && isspace((unsigned char) *after_num))
                after_num++;

        if (*after_num != '\0')
        {
                suffix = after_num;
                if (*after_num == 'k')
                {
                        /* kilobyte is the expected unit. */
                        after_num++;
                }
                else if (*after_num == 'M')
                {
                        after_num++;
                        result *= 1024.0;
                }
        }

        /* The rest can only consist of white space. */
        while (*after_num != '\0' && isspace((unsigned char) *after_num))
                after_num++;

        if (*after_num != '\0')
        {
                pg_log_error("invalid --max-rate unit: \"%s\"", suffix);
                exit(1);
        }

        /* Valid integer? */
        if ((uint64) result != (uint64) ((uint32) result))
        {
                pg_log_error("transfer rate \"%s\" exceeds integer range", src);
                exit(1);
        }

        /*
         * The range is checked on the server side too, but avoid the server
         * connection if a nonsensical value was passed.
         */
        if (result < MAX_RATE_LOWER || result > MAX_RATE_UPPER)
        {
                pg_log_error("transfer rate \"%s\" is out of range", src);
                exit(1);
        }

        return (int32) result;
}

/*
 * Read a stream of COPY data and invoke the provided callback for each
 * chunk.
 */
static void
ReceiveCopyData(PGconn *conn, WriteDataCallback callback,
                                void *callback_data)
{
        PGresult   *res;

        /* Get the COPY data stream. */
        res = PQgetResult(conn);
        if (PQresultStatus(res) != PGRES_COPY_OUT)
        {
                pg_log_error("could not get COPY data stream: %s",
                                         PQerrorMessage(conn));
                exit(1);
        }
        PQclear(res);

        /* Loop over chunks until done. */
        while (1)
        {
                int                     r;
                char       *copybuf;

                r = PQgetCopyData(conn, &copybuf, 0);
                if (r == -1)
                {
                        /* End of chunk. */
                        break;
                }
                else if (r == -2)
                {
                        pg_log_error("could not read COPY data: %s",
                                                 PQerrorMessage(conn));
                        exit(1);
                }

                (*callback) (r, copybuf, callback_data);

                PQfreemem(copybuf);
        }
}

/*
 * Write a piece of tar data
 */
static void
writeTarData(WriteTarState *state, char *buf, int r)
{
#ifdef HAVE_LIBZ
        if (state->ztarfile != NULL)
        {
                errno = 0;
                if (gzwrite(state->ztarfile, buf, r) != r)
                {
                        /* if write didn't set errno, assume problem is no disk space */
                        if (errno == 0)
                                errno = ENOSPC;
                        pg_log_error("could not write to compressed file \"%s\": %s",
                                                 state->filename, get_gz_error(state->ztarfile));
                        exit(1);
                }
        }
        else
#endif
        {
                errno = 0;
                if (fwrite(buf, r, 1, state->tarfile) != 1)
                {
                        /* if write didn't set errno, assume problem is no disk space */
                        if (errno == 0)
                                errno = ENOSPC;
                        pg_log_error("could not write to file \"%s\": %m",
                                                 state->filename);
                        exit(1);
                }
        }
}

/*
 * Receive a tar format file from the connection to the server, and write
 * the data from this file directly into a tar file. If compression is
 * enabled, the data will be compressed while written to the file.
 *
 * The file will be named base.tar[.gz] if it's for the main data directory
 * or <tablespaceoid>.tar[.gz] if it's for another tablespace.
 *
 * No attempt to inspect or validate the contents of the file is done.
 */
static void
ReceiveTarFile(PGconn *conn, PGresult *res, int rownum)
{
        char            zerobuf[TAR_BLOCK_SIZE * 2];
        WriteTarState state;

        memset(&state, 0, sizeof(state));
        state.tablespacenum = rownum;
        state.basetablespace = PQgetisnull(res, rownum, 0);
        state.in_tarhdr = true;

        /* recovery.conf is integrated into postgresql.conf in 12 and newer */
        if (PQserverVersion(conn) >= MINIMUM_VERSION_FOR_RECOVERY_GUC)
                state.is_recovery_guc_supported = true;

        if (state.basetablespace)
        {
                /*
                 * Base tablespaces
                 */
                if (strcmp(basedir, "-") == 0)
                {
#ifdef WIN32
                        _setmode(fileno(stdout), _O_BINARY);
#endif

#ifdef HAVE_LIBZ
                        if (compresslevel != 0)
                        {
                                int                     fd = dup(fileno(stdout));

                                if (fd < 0)
                                {
                                        pg_log_error("could not duplicate stdout: %m");
                                        exit(1);
                                }

                                state.ztarfile = gzdopen(fd, "wb");
                                if (state.ztarfile == NULL)
                                {
                                        pg_log_error("could not open output file: %m");
                                        exit(1);
                                }

                                if (gzsetparams(state.ztarfile, compresslevel,
                                                                Z_DEFAULT_STRATEGY) != Z_OK)
                                {
                                        pg_log_error("could not set compression level %d: %s",
                                                                 compresslevel, get_gz_error(state.ztarfile));
                                        exit(1);
                                }
                        }
                        else
#endif
                                state.tarfile = stdout;
                        strcpy(state.filename, "-");
                }
                else
                {
#ifdef HAVE_LIBZ
                        if (compresslevel != 0)
                        {
                                snprintf(state.filename, sizeof(state.filename),
                                                 "%s/base.tar.gz", basedir);
                                state.ztarfile = gzopen(state.filename, "wb");
                                if (gzsetparams(state.ztarfile, compresslevel,
                                                                Z_DEFAULT_STRATEGY) != Z_OK)
                                {
                                        pg_log_error("could not set compression level %d: %s",
                                                                 compresslevel, get_gz_error(state.ztarfile));
                                        exit(1);
                                }
                        }
                        else
#endif
                        {
                                snprintf(state.filename, sizeof(state.filename),
                                                 "%s/base.tar", basedir);
                                state.tarfile = fopen(state.filename, "wb");
                        }
                }
        }
        else
        {
                /*
                 * Specific tablespace
                 */
#ifdef HAVE_LIBZ
                if (compresslevel != 0)
                {
                        snprintf(state.filename, sizeof(state.filename),
                                         "%s/%s.tar.gz",
                                         basedir, PQgetvalue(res, rownum, 0));
                        state.ztarfile = gzopen(state.filename, "wb");
                        if (gzsetparams(state.ztarfile, compresslevel,
                                                        Z_DEFAULT_STRATEGY) != Z_OK)
                        {
                                pg_log_error("could not set compression level %d: %s",
                                                         compresslevel, get_gz_error(state.ztarfile));
                                exit(1);
                        }
                }
                else
#endif
                {
                        snprintf(state.filename, sizeof(state.filename), "%s/%s.tar",
                                         basedir, PQgetvalue(res, rownum, 0));
                        state.tarfile = fopen(state.filename, "wb");
                }
        }

#ifdef HAVE_LIBZ
        if (compresslevel != 0)
        {
                if (!state.ztarfile)
                {
                        /* Compression is in use */
                        pg_log_error("could not create compressed file \"%s\": %s",
                                                 state.filename, get_gz_error(state.ztarfile));
                        exit(1);
                }
        }
        else
#endif
        {
                /* Either no zlib support, or zlib support but compresslevel = 0 */
                if (!state.tarfile)
                {
                        pg_log_error("could not create file \"%s\": %m", state.filename);
                        exit(1);
                }
        }

        ReceiveCopyData(conn, ReceiveTarCopyChunk, &state);

        /*
         * End of copy data. If requested, and this is the base tablespace, write
         * configuration file into the tarfile. When done, close the file (but not
         * stdout).
         *
         * Also, write two completely empty blocks at the end of the tar file, as
         * required by some tar programs.
         */

        MemSet(zerobuf, 0, sizeof(zerobuf));

        if (state.basetablespace && writerecoveryconf)
        {
                char            header[TAR_BLOCK_SIZE];

                /*
                 * If postgresql.auto.conf has not been found in the streamed data,
                 * add recovery configuration to postgresql.auto.conf if recovery
                 * parameters are GUCs.  If the instance connected to is older than
                 * 12, create recovery.conf with this data otherwise.
                 */
                if (!state.found_postgresql_auto_conf || !state.is_recovery_guc_supported)
                {
                        int                     padding;

                        tarCreateHeader(header,
                                                        state.is_recovery_guc_supported ? "postgresql.auto.conf" : "recovery.conf",
                                                        NULL,
                                                        recoveryconfcontents->len,
                                                        pg_file_create_mode, 04000, 02000,
                                                        time(NULL));

                        padding = tarPaddingBytesRequired(recoveryconfcontents->len);

                        writeTarData(&state, header, sizeof(header));
                        writeTarData(&state, recoveryconfcontents->data,
                                                 recoveryconfcontents->len);
                        if (padding)
                                writeTarData(&state, zerobuf, padding);
                }

                /*
                 * standby.signal is supported only if recovery parameters are GUCs.
                 */
                if (state.is_recovery_guc_supported)
                {
                        tarCreateHeader(header, "standby.signal", NULL,
                                                        0,      /* zero-length file */
                                                        pg_file_create_mode, 04000, 02000,
                                                        time(NULL));

                        writeTarData(&state, header, sizeof(header));

                        /*
                         * we don't need to pad out to a multiple of the tar block size
                         * here, because the file is zero length, which is a multiple of
                         * any block size.
                         */
                }
        }

        /*
         * Normally, we emit the backup manifest as a separate file, but when
         * we're writing a tarfile to stdout, we don't have that option, so
         * include it in the one tarfile we've got.
         */
        if (strcmp(basedir, "-") == 0 && manifest)
        {
                char            header[TAR_BLOCK_SIZE];
                PQExpBufferData buf;

                initPQExpBuffer(&buf);
                ReceiveBackupManifestInMemory(conn, &buf);
                if (PQExpBufferDataBroken(buf))
                {
                        pg_log_error("out of memory");
                        exit(1);
                }
                tarCreateHeader(header, "backup_manifest", NULL, buf.len,
                                                pg_file_create_mode, 04000, 02000,
                                                time(NULL));
                writeTarData(&state, header, sizeof(header));
                writeTarData(&state, buf.data, buf.len);
                termPQExpBuffer(&buf);
        }

        /* 2 * TAR_BLOCK_SIZE bytes empty data at end of file */
        writeTarData(&state, zerobuf, sizeof(zerobuf));

#ifdef HAVE_LIBZ
        if (state.ztarfile != NULL)
        {
                if (gzclose(state.ztarfile) != 0)
                {
                        pg_log_error("could not close compressed file \"%s\": %s",
                                                 state.filename, get_gz_error(state.ztarfile));
                        exit(1);
                }
        }
        else
#endif
        {
                if (strcmp(basedir, "-") != 0)
                {
                        if (fclose(state.tarfile) != 0)
                        {
                                pg_log_error("could not close file \"%s\": %m",
                                                         state.filename);
                                exit(1);
                        }
                }
        }

        progress_report(rownum, state.filename, true, false);

        /*
         * Do not sync the resulting tar file yet, all files are synced once at
         * the end.
         */
}

/*
 * Receive one chunk of tar-format data from the server.
 */
static void
ReceiveTarCopyChunk(size_t r, char *copybuf, void *callback_data)
{
        WriteTarState *state = callback_data;

        if (!writerecoveryconf || !state->basetablespace)
        {
                /*
                 * When not writing config file, or when not working on the base
                 * tablespace, we never have to look for an existing configuration
                 * file in the stream.
                 */
                writeTarData(state, copybuf, r);
        }
        else
        {
                /*
                 * Look for a config file in the existing tar stream. If it's there,
                 * we must skip it so we can later overwrite it with our own version
                 * of the file.
                 *
                 * To do this, we have to process the individual files inside the TAR
                 * stream. The stream consists of a header and zero or more chunks,
                 * each with a length equal to TAR_BLOCK_SIZE. The stream from the
                 * server is broken up into smaller pieces, so we have to track the
                 * size of the files to find the next header structure.
                 */
                int                     rr = r;
                int                     pos = 0;

                while (rr > 0)
                {
                        if (state->in_tarhdr)
                        {
                                /*
                                 * We're currently reading a header structure inside the TAR
                                 * stream, i.e. the file metadata.
                                 */
                                if (state->tarhdrsz < TAR_BLOCK_SIZE)
                                {
                                        /*
                                         * Copy the header structure into tarhdr in case the
                                         * header is not aligned properly or it's not returned in
                                         * whole by the last PQgetCopyData call.
                                         */
                                        int                     hdrleft;
                                        int                     bytes2copy;

                                        hdrleft = TAR_BLOCK_SIZE - state->tarhdrsz;
                                        bytes2copy = (rr > hdrleft ? hdrleft : rr);

                                        memcpy(&state->tarhdr[state->tarhdrsz], copybuf + pos,
                                                   bytes2copy);

                                        rr -= bytes2copy;
                                        pos += bytes2copy;
                                        state->tarhdrsz += bytes2copy;
                                }
                                else
                                {
                                        /*
                                         * We have the complete header structure in tarhdr, look
                                         * at the file metadata: we may want append recovery info
                                         * into postgresql.auto.conf and skip standby.signal file
                                         * if recovery parameters are integrated as GUCs, and
                                         * recovery.conf otherwise. In both cases we must
                                         * calculate tar padding.
                                         */
                                        if (state->is_recovery_guc_supported)
                                        {
                                                state->skip_file =
                                                        (strcmp(&state->tarhdr[0], "standby.signal") == 0);
                                                state->is_postgresql_auto_conf =
                                                        (strcmp(&state->tarhdr[0], "postgresql.auto.conf") == 0);
                                        }
                                        else
                                                state->skip_file =
                                                        (strcmp(&state->tarhdr[0], "recovery.conf") == 0);

                                        state->filesz = read_tar_number(&state->tarhdr[124], 12);
                                        state->file_padding_len =
                                                tarPaddingBytesRequired(state->filesz);

                                        if (state->is_recovery_guc_supported &&
                                                state->is_postgresql_auto_conf &&
                                                writerecoveryconf)
                                        {
                                                /* replace tar header */
                                                char            header[TAR_BLOCK_SIZE];

                                                tarCreateHeader(header, "postgresql.auto.conf", NULL,
                                                                                state->filesz + recoveryconfcontents->len,
                                                                                pg_file_create_mode, 04000, 02000,
                                                                                time(NULL));

                                                writeTarData(state, header, sizeof(header));
                                        }
                                        else
                                        {
                                                /* copy stream with padding */
                                                state->filesz += state->file_padding_len;

                                                if (!state->skip_file)
                                                {
                                                        /*
                                                         * If we're not skipping the file, write the tar
                                                         * header unmodified.
                                                         */
                                                        writeTarData(state, state->tarhdr, TAR_BLOCK_SIZE);
                                                }
                                        }

                                        /* Next part is the file, not the header */
                                        state->in_tarhdr = false;
                                }
                        }
                        else
                        {
                                /*
                                 * We're processing a file's contents.
                                 */
                                if (state->filesz > 0)
                                {
                                        /*
                                         * We still have data to read (and possibly write).
                                         */
                                        int                     bytes2write;

                                        bytes2write = (state->filesz > rr ? rr : state->filesz);

                                        if (!state->skip_file)
                                                writeTarData(state, copybuf + pos, bytes2write);

                                        rr -= bytes2write;
                                        pos += bytes2write;
                                        state->filesz -= bytes2write;
                                }
                                else if (state->is_recovery_guc_supported &&
                                                 state->is_postgresql_auto_conf &&
                                                 writerecoveryconf)
                                {
                                        /* append recovery config to postgresql.auto.conf */
                                        int                     padding;
                                        int                     tailsize;

                                        tailsize = (TAR_BLOCK_SIZE - state->file_padding_len) + recoveryconfcontents->len;
                                        padding = tarPaddingBytesRequired(tailsize);

                                        writeTarData(state, recoveryconfcontents->data,
                                                                 recoveryconfcontents->len);

                                        if (padding)
                                        {
                                                char            zerobuf[TAR_BLOCK_SIZE];

                                                MemSet(zerobuf, 0, sizeof(zerobuf));
                                                writeTarData(state, zerobuf, padding);
                                        }

                                        /* skip original file padding */
                                        state->is_postgresql_auto_conf = false;
                                        state->skip_file = true;
                                        state->filesz += state->file_padding_len;

                                        state->found_postgresql_auto_conf = true;
                                }
                                else
                                {
                                        /*
                                         * No more data in the current file, the next piece of
                                         * data (if any) will be a new file header structure.
                                         */
                                        state->in_tarhdr = true;
                                        state->skip_file = false;
                                        state->is_postgresql_auto_conf = false;
                                        state->tarhdrsz = 0;
                                        state->filesz = 0;
                                }
                        }
                }
        }
        totaldone += r;
        progress_report(state->tablespacenum, state->filename, false, false);
}


/*
 * Retrieve tablespace path, either relocated or original depending on whether
 * -T was passed or not.
 */
static const char *
get_tablespace_mapping(const char *dir)
{
        TablespaceListCell *cell;
        char            canon_dir[MAXPGPATH];

        /* Canonicalize path for comparison consistency */
        strlcpy(canon_dir, dir, sizeof(canon_dir));
        canonicalize_path(canon_dir);

        for (cell = tablespace_dirs.head; cell; cell = cell->next)
                if (strcmp(canon_dir, cell->old_dir) == 0)
                        return cell->new_dir;

        return dir;
}


/*
 * Receive a tar format stream from the connection to the server, and unpack
 * the contents of it into a directory. Only files, directories and
 * symlinks are supported, no other kinds of special files.
 *
 * If the data is for the main data directory, it will be restored in the
 * specified directory. If it's for another tablespace, it will be restored
 * in the original or mapped directory.
 */
static void
ReceiveAndUnpackTarFile(PGconn *conn, PGresult *res, int rownum)
{
        UnpackTarState state;
        bool            basetablespace;

        memset(&state, 0, sizeof(state));
        state.tablespacenum = rownum;

        basetablespace = PQgetisnull(res, rownum, 0);
        if (basetablespace)
                strlcpy(state.current_path, basedir, sizeof(state.current_path));
        else
                strlcpy(state.current_path,
                                get_tablespace_mapping(PQgetvalue(res, rownum, 1)),
                                sizeof(state.current_path));

        ReceiveCopyData(conn, ReceiveTarAndUnpackCopyChunk, &state);


        if (state.file)
                fclose(state.file);

        progress_report(rownum, state.filename, true, false);

        if (state.file != NULL)
        {
                pg_log_error("COPY stream ended before last file was finished");
                exit(1);
        }

        if (basetablespace && writerecoveryconf)
                WriteRecoveryConfig(conn, basedir, recoveryconfcontents);

        /*
         * No data is synced here, everything is done for all tablespaces at the
         * end.
         */
}

static void
ReceiveTarAndUnpackCopyChunk(size_t r, char *copybuf, void *callback_data)
{
        UnpackTarState *state = callback_data;

        if (state->file == NULL)
        {
#ifndef WIN32
                int                     filemode;
#endif

                /*
                 * No current file, so this must be the header for a new file
                 */
                if (r != TAR_BLOCK_SIZE)
                {
                        pg_log_error("invalid tar block header size: %zu", r);
                        exit(1);
                }
                totaldone += TAR_BLOCK_SIZE;

                state->current_len_left = read_tar_number(&copybuf[124], 12);

#ifndef WIN32
                /* Set permissions on the file */
                filemode = read_tar_number(&copybuf[100], 8);
#endif

                /*
                 * All files are padded up to a multiple of TAR_BLOCK_SIZE
                 */
                state->current_padding =
                        tarPaddingBytesRequired(state->current_len_left);

                /*
                 * First part of header is zero terminated filename
                 */
                snprintf(state->filename, sizeof(state->filename),
                                 "%s/%s", state->current_path, copybuf);
                if (state->filename[strlen(state->filename) - 1] == '/')
                {
                        /*
                         * Ends in a slash means directory or symlink to directory
                         */
                        if (copybuf[156] == '5')
                        {
                                /*
                                 * Directory. Remove trailing slash first.
                                 */
                                state->filename[strlen(state->filename) - 1] = '\0';
                                if (mkdir(state->filename, pg_dir_create_mode) != 0)
                                {
                                        /*
                                         * When streaming WAL, pg_wal (or pg_xlog for pre-9.6
                                         * clusters) will have been created by the wal receiver
                                         * process. Also, when the WAL directory location was
                                         * specified, pg_wal (or pg_xlog) has already been created
                                         * as a symbolic link before starting the actual backup.
                                         * So just ignore creation failures on related
                                         * directories.
                                         */
                                        if (!((pg_str_endswith(state->filename, "/pg_wal") ||
                                                   pg_str_endswith(state->filename, "/pg_xlog") ||
                                                   pg_str_endswith(state->filename, "/archive_status")) &&
                                                  errno == EEXIST))
                                        {
                                                pg_log_error("could not create directory \"%s\": %m",
                                                                         state->filename);
                                                exit(1);
                                        }
                                }
#ifndef WIN32
                                if (chmod(state->filename, (mode_t) filemode))
                                {
                                        pg_log_error("could not set permissions on directory \"%s\": %m",
                                                                 state->filename);
                                        exit(1);
                                }
#endif
                        }
                        else if (copybuf[156] == '2')
                        {
                                /*
                                 * Symbolic link
                                 *
                                 * It's most likely a link in pg_tblspc directory, to the
                                 * location of a tablespace. Apply any tablespace mapping
                                 * given on the command line (--tablespace-mapping). (We
                                 * blindly apply the mapping without checking that the link
                                 * really is inside pg_tblspc. We don't expect there to be
                                 * other symlinks in a data directory, but if there are, you
                                 * can call it an undocumented feature that you can map them
                                 * too.)
                                 */
                                state->filename[strlen(state->filename) - 1] = '\0';    /* Remove trailing slash */

                                state->mapped_tblspc_path =
                                        get_tablespace_mapping(&copybuf[157]);
                                if (symlink(state->mapped_tblspc_path, state->filename) != 0)
                                {
                                        pg_log_error("could not create symbolic link from \"%s\" to \"%s\": %m",
                                                                 state->filename, state->mapped_tblspc_path);
                                        exit(1);
                                }
                        }
                        else
                        {
                                pg_log_error("unrecognized link indicator \"%c\"",
                                                         copybuf[156]);
                                exit(1);
                        }
                        return;                         /* directory or link handled */
                }

                /*
                 * regular file
                 */
                state->file = fopen(state->filename, "wb");
                if (!state->file)
                {
                        pg_log_error("could not create file \"%s\": %m", state->filename);
                        exit(1);
                }

#ifndef WIN32
                if (chmod(state->filename, (mode_t) filemode))
                {
                        pg_log_error("could not set permissions on file \"%s\": %m",
                                                 state->filename);
                        exit(1);
                }
#endif

                if (state->current_len_left == 0)
                {
                        /*
                         * Done with this file, next one will be a new tar header
                         */
                        fclose(state->file);
                        state->file = NULL;
                        return;
                }
        }                                                       /* new file */
        else
        {
                /*
                 * Continuing blocks in existing file
                 */
                if (state->current_len_left == 0 && r == state->current_padding)
                {
                        /*
                         * Received the padding block for this file, ignore it and close
                         * the file, then move on to the next tar header.
                         */
                        fclose(state->file);
                        state->file = NULL;
                        totaldone += r;
                        return;
                }

                errno = 0;
                if (fwrite(copybuf, r, 1, state->file) != 1)
                {
                        /* if write didn't set errno, assume problem is no disk space */
                        if (errno == 0)
                                errno = ENOSPC;
                        pg_log_error("could not write to file \"%s\": %m", state->filename);
                        exit(1);
                }
                totaldone += r;
                progress_report(state->tablespacenum, state->filename, false, false);

                state->current_len_left -= r;
                if (state->current_len_left == 0 && state->current_padding == 0)
                {
                        /*
                         * Received the last block, and there is no padding to be
                         * expected. Close the file and move on to the next tar header.
                         */
                        fclose(state->file);
                        state->file = NULL;
                        return;
                }
        }                                                       /* continuing data in existing file */
}

/*
 * Receive the backup manifest file and write it out to a file.
 */
static void
ReceiveBackupManifest(PGconn *conn)
{
        WriteManifestState state;

        snprintf(state.filename, sizeof(state.filename),
                         "%s/backup_manifest.tmp", basedir);
        state.file = fopen(state.filename, "wb");
        if (state.file == NULL)
        {
                pg_log_error("could not create file \"%s\": %m", state.filename);
                exit(1);
        }

        ReceiveCopyData(conn, ReceiveBackupManifestChunk, &state);

        fclose(state.file);
}

/*
 * Receive one chunk of the backup manifest file and write it out to a file.
 */
static void
ReceiveBackupManifestChunk(size_t r, char *copybuf, void *callback_data)
{
        WriteManifestState *state = callback_data;

        errno = 0;
        if (fwrite(copybuf, r, 1, state->file) != 1)
        {
                /* if write didn't set errno, assume problem is no disk space */
                if (errno == 0)
                        errno = ENOSPC;
                pg_log_error("could not write to file \"%s\": %m", state->filename);
                exit(1);
        }
}

/*
 * Receive the backup manifest file and write it out to a file.
 */
static void
ReceiveBackupManifestInMemory(PGconn *conn, PQExpBuffer buf)
{
        ReceiveCopyData(conn, ReceiveBackupManifestInMemoryChunk, buf);
}

/*
 * Receive one chunk of the backup manifest file and write it out to a file.
 */
static void
ReceiveBackupManifestInMemoryChunk(size_t r, char *copybuf,
                                                                   void *callback_data)
{
        PQExpBuffer buf = callback_data;

        appendPQExpBuffer(buf, copybuf, r);
}

static void
BaseBackup(void)
{
        PGresult   *res;
        char       *sysidentifier;
        TimeLineID      latesttli;
        TimeLineID      starttli;
        char       *basebkp;
        char            escaped_label[MAXPGPATH];
        char       *maxrate_clause = NULL;
        char       *manifest_clause = NULL;
        char       *manifest_checksums_clause = "";
        int                     i;
        char            xlogstart[64];
        char            xlogend[64];
        int                     minServerMajor,
                                maxServerMajor;
        int                     serverVersion,
                                serverMajor;
        int                     writing_to_stdout;

        Assert(conn != NULL);

        /*
         * Check server version. BASE_BACKUP command was introduced in 9.1, so we
         * can't work with servers older than 9.1.
         */
        minServerMajor = 901;
        maxServerMajor = PG_VERSION_NUM / 100;
        serverVersion = PQserverVersion(conn);
        serverMajor = serverVersion / 100;
        if (serverMajor < minServerMajor || serverMajor > maxServerMajor)
        {
                const char *serverver = PQparameterStatus(conn, "server_version");

                pg_log_error("incompatible server version %s",
                                         serverver ? serverver : "'unknown'");
                exit(1);
        }

        /*
         * If WAL streaming was requested, also check that the server is new
         * enough for that.
         */
        if (includewal == STREAM_WAL && !CheckServerVersionForStreaming(conn))
        {
                /*
                 * Error message already written in CheckServerVersionForStreaming(),
                 * but add a hint about using -X none.
                 */
                pg_log_info("HINT: use -X none or -X fetch to disable log streaming");
                exit(1);
        }

        /*
         * Build contents of configuration file if requested
         */
        if (writerecoveryconf)
                recoveryconfcontents = GenerateRecoveryConfig(conn, replication_slot);

        /*
         * Run IDENTIFY_SYSTEM so we can get the timeline
         */
        if (!RunIdentifySystem(conn, &sysidentifier, &latesttli, NULL, NULL))
                exit(1);

        /*
         * Start the actual backup
         */
        PQescapeStringConn(conn, escaped_label, label, sizeof(escaped_label), &i);

        if (maxrate > 0)
                maxrate_clause = psprintf("MAX_RATE %u", maxrate);

        if (manifest)
        {
                if (manifest_force_encode)
                        manifest_clause = "MANIFEST 'force-encode'";
                else
                        manifest_clause = "MANIFEST 'yes'";
                if (manifest_checksums != NULL)
                        manifest_checksums_clause = psprintf("MANIFEST_CHECKSUMS '%s'",
                                                                                                 manifest_checksums);
        }

        if (verbose)
                pg_log_info("initiating base backup, waiting for checkpoint to complete");

        if (showprogress && !verbose)
        {
                fprintf(stderr, "waiting for checkpoint");
                if (isatty(fileno(stderr)))
                        fprintf(stderr, "\r");
                else
                        fprintf(stderr, "\n");
        }

        basebkp =
                psprintf("BASE_BACKUP LABEL '%s' %s %s %s %s %s %s %s %s %s",
                                 escaped_label,
                                 estimatesize ? "PROGRESS" : "",
                                 includewal == FETCH_WAL ? "WAL" : "",
                                 fastcheckpoint ? "FAST" : "",
                                 includewal == NO_WAL ? "" : "NOWAIT",
                                 maxrate_clause ? maxrate_clause : "",
                                 format == 't' ? "TABLESPACE_MAP" : "",
                                 verify_checksums ? "" : "NOVERIFY_CHECKSUMS",
                                 manifest_clause ? manifest_clause : "",
                                 manifest_checksums_clause);

        if (PQsendQuery(conn, basebkp) == 0)
        {
                pg_log_error("could not send replication command \"%s\": %s",
                                         "BASE_BACKUP", PQerrorMessage(conn));
                exit(1);
        }

        /*
         * Get the starting WAL location
         */
        res = PQgetResult(conn);
        if (PQresultStatus(res) != PGRES_TUPLES_OK)
        {
                pg_log_error("could not initiate base backup: %s",
                                         PQerrorMessage(conn));
                exit(1);
        }
        if (PQntuples(res) != 1)
        {
                pg_log_error("server returned unexpected response to BASE_BACKUP command; got %d rows and %d fields, expected %d rows and %d fields",
                                         PQntuples(res), PQnfields(res), 1, 2);
                exit(1);
        }

        strlcpy(xlogstart, PQgetvalue(res, 0, 0), sizeof(xlogstart));

        if (verbose)
                pg_log_info("checkpoint completed");

        /*
         * 9.3 and later sends the TLI of the starting point. With older servers,
         * assume it's the same as the latest timeline reported by
         * IDENTIFY_SYSTEM.
         */
        if (PQnfields(res) >= 2)
                starttli = atoi(PQgetvalue(res, 0, 1));
        else
                starttli = latesttli;
        PQclear(res);
        MemSet(xlogend, 0, sizeof(xlogend));

        if (verbose && includewal != NO_WAL)
                pg_log_info("write-ahead log start point: %s on timeline %u",
                                        xlogstart, starttli);

        /*
         * Get the header
         */
        res = PQgetResult(conn);
        if (PQresultStatus(res) != PGRES_TUPLES_OK)
        {
                pg_log_error("could not get backup header: %s",
                                         PQerrorMessage(conn));
                exit(1);
        }
        if (PQntuples(res) < 1)
        {
                pg_log_error("no data returned from server");
                exit(1);
        }

        /*
         * Sum up the total size, for progress reporting
         */
        totalsize_kb = totaldone = 0;
        tablespacecount = PQntuples(res);
        for (i = 0; i < PQntuples(res); i++)
        {
                totalsize_kb += atol(PQgetvalue(res, i, 2));

                /*
                 * Verify tablespace directories are empty. Don't bother with the
                 * first once since it can be relocated, and it will be checked before
                 * we do anything anyway.
                 */
                if (format == 'p' && !PQgetisnull(res, i, 1))
                {
                        char       *path = unconstify(char *, get_tablespace_mapping(PQgetvalue(res, i, 1)));

                        verify_dir_is_empty_or_create(path, &made_tablespace_dirs, &found_tablespace_dirs);
                }
        }

        /*
         * When writing to stdout, require a single tablespace
         */
        writing_to_stdout = format == 't' && strcmp(basedir, "-") == 0;
        if (writing_to_stdout && PQntuples(res) > 1)
        {
                pg_log_error("can only write single tablespace to stdout, database has %d",
                                         PQntuples(res));
                exit(1);
        }

        /*
         * If we're streaming WAL, start the streaming session before we start
         * receiving the actual data chunks.
         */
        if (includewal == STREAM_WAL)
        {
                if (verbose)
                        pg_log_info("starting background WAL receiver");
                StartLogStreamer(xlogstart, starttli, sysidentifier);
        }

        /*
         * Start receiving chunks
         */
        for (i = 0; i < PQntuples(res); i++)
        {
                if (format == 't')
                        ReceiveTarFile(conn, res, i);
                else
                        ReceiveAndUnpackTarFile(conn, res, i);
        }                                                       /* Loop over all tablespaces */

        /*
         * Now receive backup manifest, if appropriate.
         *
         * If we're writing a tarfile to stdout, ReceiveTarFile will have already
         * processed the backup manifest and included it in the output tarfile.
         * Such a configuration doesn't allow for writing multiple files.
         *
         * If we're talking to an older server, it won't send a backup manifest,
         * so don't try to receive one.
         */
        if (!writing_to_stdout && manifest)
                ReceiveBackupManifest(conn);

        if (showprogress)
                progress_report(PQntuples(res), NULL, true, true);

        PQclear(res);

        /*
         * Get the stop position
         */
        res = PQgetResult(conn);
        if (PQresultStatus(res) != PGRES_TUPLES_OK)
        {
                pg_log_error("could not get write-ahead log end position from server: %s",
                                         PQerrorMessage(conn));
                exit(1);
        }
        if (PQntuples(res) != 1)
        {
                pg_log_error("no write-ahead log end position returned from server");
                exit(1);
        }
        strlcpy(xlogend, PQgetvalue(res, 0, 0), sizeof(xlogend));
        if (verbose && includewal != NO_WAL)
                pg_log_info("write-ahead log end point: %s", xlogend);
        PQclear(res);

        res = PQgetResult(conn);
        if (PQresultStatus(res) != PGRES_COMMAND_OK)
        {
                const char *sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);

                if (sqlstate &&
                        strcmp(sqlstate, ERRCODE_DATA_CORRUPTED) == 0)
                {
                        pg_log_error("checksum error occurred");
                        checksum_failure = true;
                }
                else
                {
                        pg_log_error("final receive failed: %s",
                                                 PQerrorMessage(conn));
                }
                exit(1);
        }

        if (bgchild > 0)
        {
#ifndef WIN32
                int                     status;
                pid_t           r;
#else
                DWORD           status;

                /*
                 * get a pointer sized version of bgchild to avoid warnings about
                 * casting to a different size on WIN64.
                 */
                intptr_t        bgchild_handle = bgchild;
                uint32          hi,
                                        lo;
#endif

                if (verbose)
                        pg_log_info("waiting for background process to finish streaming ...");

#ifndef WIN32
                if (write(bgpipe[1], xlogend, strlen(xlogend)) != strlen(xlogend))
                {
                        pg_log_info("could not send command to background pipe: %m");
                        exit(1);
                }

                /* Just wait for the background process to exit */
                r = waitpid(bgchild, &status, 0);
                if (r == (pid_t) -1)
                {
                        pg_log_error("could not wait for child process: %m");
                        exit(1);
                }
                if (r != bgchild)
                {
                        pg_log_error("child %d died, expected %d", (int) r, (int) bgchild);
                        exit(1);
                }
                if (status != 0)
                {
                        pg_log_error("%s", wait_result_to_str(status));
                        exit(1);
                }
                /* Exited normally, we're happy! */
#else                                                   /* WIN32 */

                /*
                 * On Windows, since we are in the same process, we can just store the
                 * value directly in the variable, and then set the flag that says
                 * it's there.
                 */
                if (sscanf(xlogend, "%X/%X", &hi, &lo) != 2)
                {
                        pg_log_error("could not parse write-ahead log location \"%s\"",
                                                 xlogend);
                        exit(1);
                }
                xlogendptr = ((uint64) hi) << 32 | lo;
                InterlockedIncrement(&has_xlogendptr);

                /* First wait for the thread to exit */
                if (WaitForSingleObjectEx((HANDLE) bgchild_handle, INFINITE, FALSE) !=
                        WAIT_OBJECT_0)
                {
                        _dosmaperr(GetLastError());
                        pg_log_error("could not wait for child thread: %m");
                        exit(1);
                }
                if (GetExitCodeThread((HANDLE) bgchild_handle, &status) == 0)
                {
                        _dosmaperr(GetLastError());
                        pg_log_error("could not get child thread exit status: %m");
                        exit(1);
                }
                if (status != 0)
                {
                        pg_log_error("child thread exited with error %u",
                                                 (unsigned int) status);
                        exit(1);
                }
                /* Exited normally, we're happy */
#endif
        }

        /* Free the configuration file contents */
        destroyPQExpBuffer(recoveryconfcontents);

        /*
         * End of copy data. Final result is already checked inside the loop.
         */
        PQclear(res);
        PQfinish(conn);
        conn = NULL;

        /*
         * Make data persistent on disk once backup is completed. For tar format
         * sync the parent directory and all its contents as each tar file was not
         * synced after being completed.  In plain format, all the data of the
         * base directory is synced, taking into account all the tablespaces.
         * Errors are not considered fatal.
         */
        if (do_sync)
        {
                if (verbose)
                        pg_log_info("syncing data to disk ...");
                if (format == 't')
                {
                        if (strcmp(basedir, "-") != 0)
                                (void) fsync_dir_recurse(basedir);
                }
                else
                {
                        (void) fsync_pgdata(basedir, serverVersion);
                }
        }

        /*
         * After synchronizing data to disk, perform a durable rename of
         * backup_manifest.tmp to backup_manifest, if we wrote such a file. This
         * way, a failure or system crash before we reach this point will leave us
         * without a backup_manifest file, decreasing the chances that a directory
         * we leave behind will be mistaken for a valid backup.
         */
        if (!writing_to_stdout && manifest)
        {
                char            tmp_filename[MAXPGPATH];
                char            filename[MAXPGPATH];

                if (verbose)
                        pg_log_info("renaming backup_manifest.tmp to backup_manifest");

                snprintf(tmp_filename, MAXPGPATH, "%s/backup_manifest.tmp", basedir);
                snprintf(filename, MAXPGPATH, "%s/backup_manifest", basedir);

                /* durable_rename emits its own log message in case of failure */
                if (durable_rename(tmp_filename, filename) != 0)
                        exit(1);
        }

        if (verbose)
                pg_log_info("base backup completed");
}


int
main(int argc, char **argv)
{
        static struct option long_options[] = {
                {"help", no_argument, NULL, '?'},
                {"version", no_argument, NULL, 'V'},
                {"pgdata", required_argument, NULL, 'D'},
                {"format", required_argument, NULL, 'F'},
                {"checkpoint", required_argument, NULL, 'c'},
                {"create-slot", no_argument, NULL, 'C'},
                {"max-rate", required_argument, NULL, 'r'},
                {"write-recovery-conf", no_argument, NULL, 'R'},
                {"slot", required_argument, NULL, 'S'},
                {"tablespace-mapping", required_argument, NULL, 'T'},
                {"wal-method", required_argument, NULL, 'X'},
                {"gzip", no_argument, NULL, 'z'},
                {"compress", required_argument, NULL, 'Z'},
                {"label", required_argument, NULL, 'l'},
                {"no-clean", no_argument, NULL, 'n'},
                {"no-sync", no_argument, NULL, 'N'},
                {"dbname", required_argument, NULL, 'd'},
                {"host", required_argument, NULL, 'h'},
                {"port", required_argument, NULL, 'p'},
                {"username", required_argument, NULL, 'U'},
                {"no-password", no_argument, NULL, 'w'},
                {"password", no_argument, NULL, 'W'},
                {"status-interval", required_argument, NULL, 's'},
                {"verbose", no_argument, NULL, 'v'},
                {"progress", no_argument, NULL, 'P'},
                {"waldir", required_argument, NULL, 1},
                {"no-slot", no_argument, NULL, 2},
                {"no-verify-checksums", no_argument, NULL, 3},
                {"no-estimate-size", no_argument, NULL, 4},
                {"no-manifest", no_argument, NULL, 5},
                {"manifest-force-encode", no_argument, NULL, 6},
                {"manifest-checksums", required_argument, NULL, 7},
                {NULL, 0, NULL, 0}
        };
        int                     c;

        int                     option_index;

        pg_logging_init(argv[0]);
        progname = get_progname(argv[0]);
        set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_basebackup"));

        if (argc > 1)
        {
                if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
                {
                        usage();
                        exit(0);
                }
                else if (strcmp(argv[1], "-V") == 0
                                 || strcmp(argv[1], "--version") == 0)
                {
                        puts("pg_basebackup (PostgreSQL) " PG_VERSION);
                        exit(0);
                }
        }

        atexit(cleanup_directories_atexit);

        while ((c = getopt_long(argc, argv, "CD:F:r:RS:T:X:l:nNzZ:d:c:h:p:U:s:wWkvP",
                                                        long_options, &option_index)) != -1)
        {
                switch (c)
                {
                        case 'C':
                                create_slot = true;
                                break;
                        case 'D':
                                basedir = pg_strdup(optarg);
                                break;
                        case 'F':
                                if (strcmp(optarg, "p") == 0 || strcmp(optarg, "plain") == 0)
                                        format = 'p';
                                else if (strcmp(optarg, "t") == 0 || strcmp(optarg, "tar") == 0)
                                        format = 't';
                                else
                                {
                                        pg_log_error("invalid output format \"%s\", must be \"plain\" or \"tar\"",
                                                                 optarg);
                                        exit(1);
                                }
                                break;
                        case 'r':
                                maxrate = parse_max_rate(optarg);
                                break;
                        case 'R':
                                writerecoveryconf = true;
                                break;
                        case 'S':

                                /*
                                 * When specifying replication slot name, use a permanent
                                 * slot.
                                 */
                                replication_slot = pg_strdup(optarg);
                                temp_replication_slot = false;
                                break;
                        case 2:
                                no_slot = true;
                                break;
                        case 'T':
                                tablespace_list_append(optarg);
                                break;
                        case 'X':
                                if (strcmp(optarg, "n") == 0 ||
                                        strcmp(optarg, "none") == 0)
                                {
                                        includewal = NO_WAL;
                                }
                                else if (strcmp(optarg, "f") == 0 ||
                                                 strcmp(optarg, "fetch") == 0)
                                {
                                        includewal = FETCH_WAL;
                                }
                                else if (strcmp(optarg, "s") == 0 ||
                                                 strcmp(optarg, "stream") == 0)
                                {
                                        includewal = STREAM_WAL;
                                }
                                else
                                {
                                        pg_log_error("invalid wal-method option \"%s\", must be \"fetch\", \"stream\", or \"none\"",
                                                                 optarg);
                                        exit(1);
                                }
                                break;
                        case 1:
                                xlog_dir = pg_strdup(optarg);
                                break;
                        case 'l':
                                label = pg_strdup(optarg);
                                break;
                        case 'n':
                                noclean = true;
                                break;
                        case 'N':
                                do_sync = false;
                                break;
                        case 'z':
#ifdef HAVE_LIBZ
                                compresslevel = Z_DEFAULT_COMPRESSION;
#else
                                compresslevel = 1;      /* will be rejected below */
#endif
                                break;
                        case 'Z':
                                if (!option_parse_int(optarg, "-Z/--compress", 0, 9,
                                                                          &compresslevel))
                                        exit(1);
                                break;
                        case 'c':
                                if (pg_strcasecmp(optarg, "fast") == 0)
                                        fastcheckpoint = true;
                                else if (pg_strcasecmp(optarg, "spread") == 0)
                                        fastcheckpoint = false;
                                else
                                {
                                        pg_log_error("invalid checkpoint argument \"%s\", must be \"fast\" or \"spread\"",
                                                                 optarg);
                                        exit(1);
                                }
                                break;
                        case 'd':
                                connection_string = pg_strdup(optarg);
                                break;
                        case 'h':
                                dbhost = pg_strdup(optarg);
                                break;
                        case 'p':
                                dbport = pg_strdup(optarg);
                                break;
                        case 'U':
                                dbuser = pg_strdup(optarg);
                                break;
                        case 'w':
                                dbgetpassword = -1;
                                break;
                        case 'W':
                                dbgetpassword = 1;
                                break;
                        case 's':
                                if (!option_parse_int(optarg, "-s/--status-interval", 0,
                                                                          INT_MAX / 1000,
                                                                          &standby_message_timeout))
                                        exit(1);
                                standby_message_timeout *= 1000;
                                break;
                        case 'v':
                                verbose++;
                                break;
                        case 'P':
                                showprogress = true;
                                break;
                        case 3:
                                verify_checksums = false;
                                break;
                        case 4:
                                estimatesize = false;
                                break;
                        case 5:
                                manifest = false;
                                break;
                        case 6:
                                manifest_force_encode = true;
                                break;
                        case 7:
                                manifest_checksums = pg_strdup(optarg);
                                break;
                        default:

                                /*
                                 * getopt_long already emitted a complaint
                                 */
                                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                                progname);
                                exit(1);
                }
        }

        /*
         * Any non-option arguments?
         */
        if (optind < argc)
        {
                pg_log_error("too many command-line arguments (first is \"%s\")",
                                         argv[optind]);
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        /*
         * Required arguments
         */
        if (basedir == NULL)
        {
                pg_log_error("no target directory specified");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        /*
         * Mutually exclusive arguments
         */
        if (format == 'p' && compresslevel != 0)
        {
                pg_log_error("only tar mode backups can be compressed");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        if (format == 't' && includewal == STREAM_WAL && strcmp(basedir, "-") == 0)
        {
                pg_log_error("cannot stream write-ahead logs in tar mode to stdout");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        if (replication_slot && includewal != STREAM_WAL)
        {
                pg_log_error("replication slots can only be used with WAL streaming");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        if (no_slot)
        {
                if (replication_slot)
                {
                        pg_log_error("--no-slot cannot be used with slot name");
                        fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                        progname);
                        exit(1);
                }
                temp_replication_slot = false;
        }

        if (create_slot)
        {
                if (!replication_slot)
                {
                        pg_log_error("%s needs a slot to be specified using --slot",
                                                 "--create-slot");
                        fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                        progname);
                        exit(1);
                }

                if (no_slot)
                {
                        pg_log_error("%s and %s are incompatible options",
                                                 "--create-slot", "--no-slot");
                        fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                        progname);
                        exit(1);
                }
        }

        if (xlog_dir)
        {
                if (format != 'p')
                {
                        pg_log_error("WAL directory location can only be specified in plain mode");
                        fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                        progname);
                        exit(1);
                }

                /* clean up xlog directory name, check it's absolute */
                canonicalize_path(xlog_dir);
                if (!is_absolute_path(xlog_dir))
                {
                        pg_log_error("WAL directory location must be an absolute path");
                        fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                        progname);
                        exit(1);
                }
        }

#ifndef HAVE_LIBZ
        if (compresslevel != 0)
        {
                pg_log_error("this build does not support compression");
                exit(1);
        }
#endif

        if (showprogress && !estimatesize)
        {
                pg_log_error("%s and %s are incompatible options",
                                         "--progress", "--no-estimate-size");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        if (!manifest && manifest_checksums != NULL)
        {
                pg_log_error("%s and %s are incompatible options",
                                         "--no-manifest", "--manifest-checksums");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        if (!manifest && manifest_force_encode)
        {
                pg_log_error("%s and %s are incompatible options",
                                         "--no-manifest", "--manifest-force-encode");
                fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
                                progname);
                exit(1);
        }

        /* connection in replication mode to server */
        conn = GetConnection();
        if (!conn)
        {
                /* Error message already written in GetConnection() */
                exit(1);
        }
        atexit(disconnect_atexit);

        /*
         * Set umask so that directories/files are created with the same
         * permissions as directories/files in the source data directory.
         *
         * pg_mode_mask is set to owner-only by default and then updated in
         * GetConnection() where we get the mode from the server-side with
         * RetrieveDataDirCreatePerm() and then call SetDataDirectoryCreatePerm().
         */
        umask(pg_mode_mask);

        /* Backup manifests are supported in 13 and newer versions */
        if (PQserverVersion(conn) < MINIMUM_VERSION_FOR_MANIFESTS)
                manifest = false;

        /*
         * Verify that the target directory exists, or create it. For plaintext
         * backups, always require the directory. For tar backups, require it
         * unless we are writing to stdout.
         */
        if (format == 'p' || strcmp(basedir, "-") != 0)
                verify_dir_is_empty_or_create(basedir, &made_new_pgdata, &found_existing_pgdata);

        /* determine remote server's xlog segment size */
        if (!RetrieveWalSegSize(conn))
                exit(1);

        /* Create pg_wal symlink, if required */
        if (xlog_dir)
        {
                char       *linkloc;

                verify_dir_is_empty_or_create(xlog_dir, &made_new_xlogdir, &found_existing_xlogdir);

                /*
                 * Form name of the place where the symlink must go. pg_xlog has been
                 * renamed to pg_wal in post-10 clusters.
                 */
                linkloc = psprintf("%s/%s", basedir,
                                                   PQserverVersion(conn) < MINIMUM_VERSION_FOR_PG_WAL ?
                                                   "pg_xlog" : "pg_wal");

#ifdef HAVE_SYMLINK
                if (symlink(xlog_dir, linkloc) != 0)
                {
                        pg_log_error("could not create symbolic link \"%s\": %m", linkloc);
                        exit(1);
                }
#else
                pg_log_error("symlinks are not supported on this platform");
                exit(1);
#endif
                free(linkloc);
        }

        BaseBackup();

        success = true;
        return 0;
}