greenplumn pg_recvlogical 源码
greenplumn pg_recvlogical 代码
文件路径：/src/bin/pg_basebackup/pg_recvlogical.c
/*-------------------------------------------------------------------------
*
* pg_recvlogical.c - receive data from a logical decoding slot in a streaming
* fashion and write it to a local file.
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
*
* IDENTIFICATION
* src/bin/pg_basebackup/pg_recvlogical.c
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
/* local includes */
#include "streamutil.h"
#include "access/xlog_internal.h"
#include "common/file_perm.h"
#include "common/fe_memutils.h"
#include "common/logging.h"
#include "getopt_long.h"
#include "libpq-fe.h"
#include "libpq/pqsignal.h"
#include "pqexpbuffer.h"
/* Time to sleep between reconnection attempts */
#define RECONNECT_SLEEP_TIME 5
/* Global Options */
static char *outfile = NULL;
static int verbose = 0;
static int noloop = 0;
static int standby_message_timeout = 10 * 1000; /* 10 sec = default */
static int fsync_interval = 10 * 1000; /* 10 sec = default */
static XLogRecPtr startpos = InvalidXLogRecPtr;
static XLogRecPtr endpos = InvalidXLogRecPtr;
static bool do_create_slot = false;
static bool slot_exists_ok = false;
static bool do_start_slot = false;
static bool do_drop_slot = false;
static char *replication_slot = NULL;
/* filled pairwise with option, value. value may be NULL */
static char **options;
static size_t noptions = 0;
static const char *plugin = "test_decoding";
/* Global State */
static int outfd = -1;
static volatile sig_atomic_t time_to_abort = false;
static volatile sig_atomic_t output_reopen = false;
static bool output_isfile;
static TimestampTz output_last_fsync = -1;
static bool output_needs_fsync = false;
static XLogRecPtr output_written_lsn = InvalidXLogRecPtr;
static XLogRecPtr output_fsync_lsn = InvalidXLogRecPtr;
static void usage(void);
static void StreamLogicalLog(void);
static bool flushAndSendFeedback(PGconn *conn, TimestampTz *now);
static void prepareToTerminate(PGconn *conn, XLogRecPtr endpos,
bool keepalive, XLogRecPtr lsn);
static void
usage(void)
{
printf(_("%s controls PostgreSQL logical decoding streams.\n\n"),
progname);
printf(_("Usage:\n"));
printf(_(" %s [OPTION]...\n"), progname);
printf(_("\nAction to be performed:\n"));
printf(_(" --create-slot create a new replication slot (for the slot's name see --slot)\n"));
printf(_(" --drop-slot drop the replication slot (for the slot's name see --slot)\n"));
printf(_(" --start start streaming in a replication slot (for the slot's name see --slot)\n"));
printf(_("\nOptions:\n"));
printf(_(" -E, --endpos=LSN exit after receiving the specified LSN\n"));
printf(_(" -f, --file=FILE receive log into this file, - for stdout\n"));
printf(_(" -F --fsync-interval=SECS\n"
" time between fsyncs to the output file (default: %d)\n"), (fsync_interval / 1000));
printf(_(" --if-not-exists do not error if slot already exists when creating a slot\n"));
printf(_(" -I, --startpos=LSN where in an existing slot should the streaming start\n"));
printf(_(" -n, --no-loop do not loop on connection lost\n"));
printf(_(" -o, --option=NAME[=VALUE]\n"
" pass option NAME with optional value VALUE to the\n"
" output plugin\n"));
printf(_(" -P, --plugin=PLUGIN use output plugin PLUGIN (default: %s)\n"), plugin);
printf(_(" -s, --status-interval=SECS\n"
" time between status packets sent to server (default: %d)\n"), (standby_message_timeout / 1000));
printf(_(" -S, --slot=SLOTNAME name of the logical replication slot\n"));
printf(_(" -v, --verbose output verbose messages\n"));
printf(_(" -V, --version output version information, then exit\n"));
printf(_(" -?, --help show this help, then exit\n"));
printf(_("\nConnection options:\n"));
printf(_(" -d, --dbname=DBNAME database to connect to\n"));
printf(_(" -h, --host=HOSTNAME database server host or socket directory\n"));
printf(_(" -p, --port=PORT database server port number\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 <pgsql-bugs@lists.postgresql.org>.\n"));
}
/*
* Send a Standby Status Update message to server.
*/
static bool
sendFeedback(PGconn *conn, TimestampTz now, bool force, bool replyRequested)
{
static XLogRecPtr last_written_lsn = InvalidXLogRecPtr;
static XLogRecPtr last_fsync_lsn = InvalidXLogRecPtr;
char replybuf[1 + 8 + 8 + 8 + 8 + 1];
int len = 0;
/*
* we normally don't want to send superfluous feedback, but if it's
* because of a timeout we need to, otherwise wal_sender_timeout will kill
* us.
*/
if (!force &&
last_written_lsn == output_written_lsn &&
last_fsync_lsn != output_fsync_lsn)
return true;
if (verbose)
pg_log_info("confirming write up to %X/%X, flush to %X/%X (slot %s)",
(uint32) (output_written_lsn >> 32), (uint32) output_written_lsn,
(uint32) (output_fsync_lsn >> 32), (uint32) output_fsync_lsn,
replication_slot);
replybuf[len] = 'r';
len += 1;
fe_sendint64(output_written_lsn, &replybuf[len]); /* write */
len += 8;
fe_sendint64(output_fsync_lsn, &replybuf[len]); /* flush */
len += 8;
fe_sendint64(InvalidXLogRecPtr, &replybuf[len]); /* apply */
len += 8;
fe_sendint64(now, &replybuf[len]); /* sendTime */
len += 8;
replybuf[len] = replyRequested ? 1 : 0; /* replyRequested */
len += 1;
startpos = output_written_lsn;
last_written_lsn = output_written_lsn;
last_fsync_lsn = output_fsync_lsn;
if (PQputCopyData(conn, replybuf, len) <= 0 || PQflush(conn))
{
pg_log_error("could not send feedback packet: %s",
PQerrorMessage(conn));
return false;
}
return true;
}
static void
disconnect_atexit(void)
{
if (conn != NULL)
PQfinish(conn);
}
static bool
OutputFsync(TimestampTz now)
{
output_last_fsync = now;
output_fsync_lsn = output_written_lsn;
if (fsync_interval <= 0)
return true;
if (!output_needs_fsync)
return true;
output_needs_fsync = false;
/* can only fsync if it's a regular file */
if (!output_isfile)
return true;
if (fsync(outfd) != 0)
{
pg_log_error("could not fsync file \"%s\": %m", outfile);
return false;
}
return true;
}
/*
* Start the log streaming
*/
static void
StreamLogicalLog(void)
{
PGresult *res;
char *copybuf = NULL;
TimestampTz last_status = -1;
int i;
PQExpBuffer query;
output_written_lsn = InvalidXLogRecPtr;
output_fsync_lsn = InvalidXLogRecPtr;
query = createPQExpBuffer();
/*
* Connect in replication mode to the server
*/
if (!conn)
conn = GetConnection();
if (!conn)
/* Error message already written in GetConnection() */
return;
/*
* Start the replication
*/
if (verbose)
pg_log_info("starting log streaming at %X/%X (slot %s)",
(uint32) (startpos >> 32), (uint32) startpos,
replication_slot);
/* Initiate the replication stream at specified location */
appendPQExpBuffer(query, "START_REPLICATION SLOT \"%s\" LOGICAL %X/%X",
replication_slot, (uint32) (startpos >> 32), (uint32) startpos);
/* print options if there are any */
if (noptions)
appendPQExpBufferStr(query, " (");
for (i = 0; i < noptions; i++)
{
/* separator */
if (i > 0)
appendPQExpBufferStr(query, ", ");
/* write option name */
appendPQExpBuffer(query, "\"%s\"", options[(i * 2)]);
/* write option value if specified */
if (options[(i * 2) + 1] != NULL)
appendPQExpBuffer(query, " '%s'", options[(i * 2) + 1]);
}
if (noptions)
appendPQExpBufferChar(query, ')');
res = PQexec(conn, query->data);
if (PQresultStatus(res) != PGRES_COPY_BOTH)
{
pg_log_error("could not send replication command \"%s\": %s",
query->data, PQresultErrorMessage(res));
PQclear(res);
goto error;
}
PQclear(res);
resetPQExpBuffer(query);
if (verbose)
pg_log_info("streaming initiated");
while (!time_to_abort)
{
int r;
int bytes_left;
int bytes_written;
TimestampTz now;
int hdr_len;
XLogRecPtr cur_record_lsn = InvalidXLogRecPtr;
if (copybuf != NULL)
{
PQfreemem(copybuf);
copybuf = NULL;
}
/*
* Potentially send a status message to the master
*/
now = feGetCurrentTimestamp();
if (outfd != -1 &&
feTimestampDifferenceExceeds(output_last_fsync, now,
fsync_interval))
{
if (!OutputFsync(now))
goto error;
}
if (standby_message_timeout > 0 &&
feTimestampDifferenceExceeds(last_status, now,
standby_message_timeout))
{
/* Time to send feedback! */
if (!sendFeedback(conn, now, true, false))
goto error;
last_status = now;
}
/* got SIGHUP, close output file */
if (outfd != -1 && output_reopen && strcmp(outfile, "-") != 0)
{
now = feGetCurrentTimestamp();
if (!OutputFsync(now))
goto error;
close(outfd);
outfd = -1;
}
output_reopen = false;
/* open the output file, if not open yet */
if (outfd == -1)
{
struct stat statbuf;
if (strcmp(outfile, "-") == 0)
outfd = fileno(stdout);
else
outfd = open(outfile, O_CREAT | O_APPEND | O_WRONLY | PG_BINARY,
S_IRUSR | S_IWUSR);
if (outfd == -1)
{
pg_log_error("could not open log file \"%s\": %m", outfile);
goto error;
}
if (fstat(outfd, &statbuf) != 0)
pg_log_error("could not stat file \"%s\": %m", outfile);
output_isfile = S_ISREG(statbuf.st_mode) && !isatty(outfd);
}
r = PQgetCopyData(conn, ©buf, 1);
if (r == 0)
{
/*
* In async mode, and no data available. We block on reading but
* not more than the specified timeout, so that we can send a
* response back to the client.
*/
fd_set input_mask;
TimestampTz message_target = 0;
TimestampTz fsync_target = 0;
struct timeval timeout;
struct timeval *timeoutptr = NULL;
if (PQsocket(conn) < 0)
{
pg_log_error("invalid socket: %s", PQerrorMessage(conn));
goto error;
}
FD_ZERO(&input_mask);
FD_SET(PQsocket(conn), &input_mask);
/* Compute when we need to wakeup to send a keepalive message. */
if (standby_message_timeout)
message_target = last_status + (standby_message_timeout - 1) *
((int64) 1000);
/* Compute when we need to wakeup to fsync the output file. */
if (fsync_interval > 0 && output_needs_fsync)
fsync_target = output_last_fsync + (fsync_interval - 1) *
((int64) 1000);
/* Now compute when to wakeup. */
if (message_target > 0 || fsync_target > 0)
{
TimestampTz targettime;
long secs;
int usecs;
targettime = message_target;
if (fsync_target > 0 && fsync_target < targettime)
targettime = fsync_target;
feTimestampDifference(now,
targettime,
&secs,
&usecs);
if (secs <= 0)
timeout.tv_sec = 1; /* Always sleep at least 1 sec */
else
timeout.tv_sec = secs;
timeout.tv_usec = usecs;
timeoutptr = &timeout;
}
r = select(PQsocket(conn) + 1, &input_mask, NULL, NULL, timeoutptr);
if (r == 0 || (r < 0 && errno == EINTR))
{
/*
* Got a timeout or signal. Continue the loop and either
* deliver a status packet to the server or just go back into
* blocking.
*/
continue;
}
else if (r < 0)
{
pg_log_error("select() failed: %m");
goto error;
}
/* Else there is actually data on the socket */
if (PQconsumeInput(conn) == 0)
{
pg_log_error("could not receive data from WAL stream: %s",
PQerrorMessage(conn));
goto error;
}
continue;
}
/* End of copy stream */
if (r == -1)
break;
/* Failure while reading the copy stream */
if (r == -2)
{
pg_log_error("could not read COPY data: %s",
PQerrorMessage(conn));
goto error;
}
/* Check the message type. */
if (copybuf[0] == 'k')
{
int pos;
bool replyRequested;
XLogRecPtr walEnd;
bool endposReached = false;
/*
* Parse the keepalive message, enclosed in the CopyData message.
* We just check if the server requested a reply, and ignore the
* rest.
*/
pos = 1; /* skip msgtype 'k' */
walEnd = fe_recvint64(©buf[pos]);
output_written_lsn = Max(walEnd, output_written_lsn);
pos += 8; /* read walEnd */
pos += 8; /* skip sendTime */
if (r < pos + 1)
{
pg_log_error("streaming header too small: %d", r);
goto error;
}
replyRequested = copybuf[pos];
if (endpos != InvalidXLogRecPtr && walEnd >= endpos)
{
/*
* If there's nothing to read on the socket until a keepalive
* we know that the server has nothing to send us; and if
* walEnd has passed endpos, we know nothing else can have
* committed before endpos. So we can bail out now.
*/
endposReached = true;
}
/* Send a reply, if necessary */
if (replyRequested || endposReached)
{
if (!flushAndSendFeedback(conn, &now))
goto error;
last_status = now;
}
if (endposReached)
{
prepareToTerminate(conn, endpos, true, InvalidXLogRecPtr);
time_to_abort = true;
break;
}
continue;
}
else if (copybuf[0] != 'w')
{
pg_log_error("unrecognized streaming header: \"%c\"",
copybuf[0]);
goto error;
}
/*
* Read the header of the XLogData message, enclosed in the CopyData
* message. We only need the WAL location field (dataStart), the rest
* of the header is ignored.
*/
hdr_len = 1; /* msgtype 'w' */
hdr_len += 8; /* dataStart */
hdr_len += 8; /* walEnd */
hdr_len += 8; /* sendTime */
if (r < hdr_len + 1)
{
pg_log_error("streaming header too small: %d", r);
goto error;
}
/* Extract WAL location for this block */
cur_record_lsn = fe_recvint64(©buf[1]);
if (endpos != InvalidXLogRecPtr && cur_record_lsn > endpos)
{
/*
* We've read past our endpoint, so prepare to go away being
* cautious about what happens to our output data.
*/
if (!flushAndSendFeedback(conn, &now))
goto error;
prepareToTerminate(conn, endpos, false, cur_record_lsn);
time_to_abort = true;
break;
}
output_written_lsn = Max(cur_record_lsn, output_written_lsn);
bytes_left = r - hdr_len;
bytes_written = 0;
/* signal that a fsync is needed */
output_needs_fsync = true;
while (bytes_left)
{
int ret;
ret = write(outfd,
copybuf + hdr_len + bytes_written,
bytes_left);
if (ret < 0)
{
pg_log_error("could not write %u bytes to log file \"%s\": %m",
bytes_left, outfile);
goto error;
}
/* Write was successful, advance our position */
bytes_written += ret;
bytes_left -= ret;
}
if (write(outfd, "\n", 1) != 1)
{
pg_log_error("could not write %u bytes to log file \"%s\": %m",
1, outfile);
goto error;
}
if (endpos != InvalidXLogRecPtr && cur_record_lsn == endpos)
{
/* endpos was exactly the record we just processed, we're done */
if (!flushAndSendFeedback(conn, &now))
goto error;
prepareToTerminate(conn, endpos, false, cur_record_lsn);
time_to_abort = true;
break;
}
}
res = PQgetResult(conn);
if (PQresultStatus(res) == PGRES_COPY_OUT)
{
/*
* We're doing a client-initiated clean exit and have sent CopyDone to
* the server. We've already sent replay confirmation and fsync'd so
* we can just clean up the connection now.
*/
goto error;
}
else if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
pg_log_error("unexpected termination of replication stream: %s",
PQresultErrorMessage(res));
goto error;
}
PQclear(res);
if (outfd != -1 && strcmp(outfile, "-") != 0)
{
TimestampTz t = feGetCurrentTimestamp();
/* no need to jump to error on failure here, we're finishing anyway */
OutputFsync(t);
if (close(outfd) != 0)
pg_log_error("could not close file \"%s\": %m", outfile);
}
outfd = -1;
error:
if (copybuf != NULL)
{
PQfreemem(copybuf);
copybuf = NULL;
}
destroyPQExpBuffer(query);
PQfinish(conn);
conn = NULL;
}
/*
* Unfortunately we can't do sensible signal handling on windows...
*/
#ifndef WIN32
/*
* When sigint is called, just tell the system to exit at the next possible
* moment.
*/
static void
sigint_handler(int signum)
{
time_to_abort = true;
}
/*
* Trigger the output file to be reopened.
*/
static void
sighup_handler(int signum)
{
output_reopen = true;
}
#endif
int
main(int argc, char **argv)
{
static struct option long_options[] = {
/* general options */
{"file", required_argument, NULL, 'f'},
{"fsync-interval", required_argument, NULL, 'F'},
{"no-loop", no_argument, NULL, 'n'},
{"verbose", no_argument, NULL, 'v'},
{"version", no_argument, NULL, 'V'},
{"help", no_argument, NULL, '?'},
/* connection options */
{"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'},
/* replication options */
{"startpos", required_argument, NULL, 'I'},
{"endpos", required_argument, NULL, 'E'},
{"option", required_argument, NULL, 'o'},
{"plugin", required_argument, NULL, 'P'},
{"status-interval", required_argument, NULL, 's'},
{"slot", required_argument, NULL, 'S'},
/* action */
{"create-slot", no_argument, NULL, 1},
{"start", no_argument, NULL, 2},
{"drop-slot", no_argument, NULL, 3},
{"if-not-exists", no_argument, NULL, 4},
{NULL, 0, NULL, 0}
};
int c;
int option_index;
uint32 hi,
lo;
char *db_name;
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_recvlogical (PostgreSQL) " PG_VERSION);
exit(0);
}
}
while ((c = getopt_long(argc, argv, "E:f:F:nvd:h:p:U:wWI:o:P:s:S:",
long_options, &option_index)) != -1)
{
switch (c)
{
/* general options */
case 'f':
outfile = pg_strdup(optarg);
break;
case 'F':
fsync_interval = atoi(optarg) * 1000;
if (fsync_interval < 0)
{
pg_log_error("invalid fsync interval \"%s\"", optarg);
exit(1);
}
break;
case 'n':
noloop = 1;
break;
case 'v':
verbose++;
break;
/* connection options */
case 'd':
dbname = pg_strdup(optarg);
break;
case 'h':
dbhost = pg_strdup(optarg);
break;
case 'p':
if (atoi(optarg) <= 0)
{
pg_log_error("invalid port number \"%s\"", optarg);
exit(1);
}
dbport = pg_strdup(optarg);
break;
case 'U':
dbuser = pg_strdup(optarg);
break;
case 'w':
dbgetpassword = -1;
break;
case 'W':
dbgetpassword = 1;
break;
/* replication options */
case 'I':
if (sscanf(optarg, "%X/%X", &hi, &lo) != 2)
{
pg_log_error("could not parse start position \"%s\"", optarg);
exit(1);
}
startpos = ((uint64) hi) << 32 | lo;
break;
case 'E':
if (sscanf(optarg, "%X/%X", &hi, &lo) != 2)
{
pg_log_error("could not parse end position \"%s\"", optarg);
exit(1);
}
endpos = ((uint64) hi) << 32 | lo;
break;
case 'o':
{
char *data = pg_strdup(optarg);
char *val = strchr(data, '=');
if (val != NULL)
{
/* remove =; separate data from val */
*val = '\0';
val++;
}
noptions += 1;
options = pg_realloc(options, sizeof(char *) * noptions * 2);
options[(noptions - 1) * 2] = data;
options[(noptions - 1) * 2 + 1] = val;
}
break;
case 'P':
plugin = pg_strdup(optarg);
break;
case 's':
standby_message_timeout = atoi(optarg) * 1000;
if (standby_message_timeout < 0)
{
pg_log_error("invalid status interval \"%s\"", optarg);
exit(1);
}
break;
case 'S':
replication_slot = pg_strdup(optarg);
break;
/* action */
case 1:
do_create_slot = true;
break;
case 2:
do_start_slot = true;
break;
case 3:
do_drop_slot = true;
break;
case 4:
slot_exists_ok = true;
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 (replication_slot == NULL)
{
pg_log_error("no slot specified");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
if (do_start_slot && outfile == NULL)
{
pg_log_error("no target file specified");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
if (!do_drop_slot && dbname == NULL)
{
pg_log_error("no database specified");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
if (!do_drop_slot && !do_create_slot && !do_start_slot)
{
pg_log_error("at least one action needs to be specified");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
if (do_drop_slot && (do_create_slot || do_start_slot))
{
pg_log_error("cannot use --create-slot or --start together with --drop-slot");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
if (startpos != InvalidXLogRecPtr && (do_create_slot || do_drop_slot))
{
pg_log_error("cannot use --create-slot or --drop-slot together with --startpos");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
if (endpos != InvalidXLogRecPtr && !do_start_slot)
{
pg_log_error("--endpos may only be specified with --start");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
progname);
exit(1);
}
#ifndef WIN32
pqsignal(SIGINT, sigint_handler);
pqsignal(SIGHUP, sighup_handler);
#endif
/*
* Obtain a connection to server. This is not really necessary but it
* helps to get more precise error messages about authentication, required
* GUC parameters and such.
*/
conn = GetConnection();
if (!conn)
/* Error message already written in GetConnection() */
exit(1);
atexit(disconnect_atexit);
/*
* Run IDENTIFY_SYSTEM to make sure we connected using a database specific
* replication connection.
*/
if (!RunIdentifySystem(conn, NULL, NULL, NULL, &db_name))
exit(1);
if (db_name == NULL)
{
pg_log_error("could not establish database-specific replication connection");
exit(1);
}
/*
* 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);
/* Drop a replication slot. */
if (do_drop_slot)
{
if (verbose)
pg_log_info("dropping replication slot \"%s\"", replication_slot);
if (!DropReplicationSlot(conn, replication_slot))
exit(1);
}
/* Create a replication slot. */
if (do_create_slot)
{
if (verbose)
pg_log_info("creating replication slot \"%s\"", replication_slot);
if (!CreateReplicationSlot(conn, replication_slot, plugin, false,
false, false, slot_exists_ok))
exit(1);
startpos = InvalidXLogRecPtr;
}
if (!do_start_slot)
exit(0);
/* Stream loop */
while (true)
{
StreamLogicalLog();
if (time_to_abort)
{
/*
* We've been Ctrl-C'ed or reached an exit limit condition. That's
* not an error, so exit without an errorcode.
*/
exit(0);
}
else if (noloop)
{
pg_log_error("disconnected");
exit(1);
}
else
{
/* translator: check source for value for %d */
pg_log_info("disconnected; waiting %d seconds to try again",
RECONNECT_SLEEP_TIME);
pg_usleep(RECONNECT_SLEEP_TIME * 1000000);
}
}
}
/*
* Fsync our output data, and send a feedback message to the server. Returns
* true if successful, false otherwise.
*
* If successful, *now is updated to the current timestamp just before sending
* feedback.
*/
static bool
flushAndSendFeedback(PGconn *conn, TimestampTz *now)
{
/* flush data to disk, so that we send a recent flush pointer */
if (!OutputFsync(*now))
return false;
*now = feGetCurrentTimestamp();
if (!sendFeedback(conn, *now, true, false))
return false;
return true;
}
/*
* Try to inform the server about our upcoming demise, but don't wait around or
* retry on failure.
*/
static void
prepareToTerminate(PGconn *conn, XLogRecPtr endpos, bool keepalive, XLogRecPtr lsn)
{
(void) PQputCopyEnd(conn, NULL);
(void) PQflush(conn);
if (verbose)
{
if (keepalive)
pg_log_info("endpos %X/%X reached by keepalive",
(uint32) (endpos >> 32), (uint32) endpos);
else
pg_log_info("endpos %X/%X reached by record at %X/%X",
(uint32) (endpos >> 32), (uint32) (endpos),
(uint32) (lsn >> 32), (uint32) lsn);
}
}
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