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Diffstat (limited to 'src/bin/pg_basebackup/receivelog.c')
-rw-r--r--src/bin/pg_basebackup/receivelog.c687
1 files changed, 487 insertions, 200 deletions
diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
index 88d0c136b07..03e275cb5b6 100644
--- a/src/bin/pg_basebackup/receivelog.c
+++ b/src/bin/pg_basebackup/receivelog.c
@@ -28,19 +28,24 @@
#include "streamutil.h"
-/* fd for currently open WAL file */
+/* fd and filename for currently open WAL file */
static int walfile = -1;
+static char current_walfile_name[MAXPGPATH] = "";
+
+static bool HandleCopyStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
+ char *basedir, stream_stop_callback stream_stop,
+ int standby_message_timeout, char *partial_suffix,
+ XLogRecPtr *stoppos);
/*
- * Open a new WAL file in the specified directory. Store the name
- * (not including the full directory) in namebuf. Assumes there is
- * enough room in this buffer...
+ * Open a new WAL file in the specified directory.
*
- * The file will be padded to 16Mb with zeroes.
+ * The file will be padded to 16Mb with zeroes. The base filename (without
+ * partial_suffix) is stored in current_walfile_name.
*/
-static int
+static bool
open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir,
- char *namebuf)
+ char *partial_suffix)
{
int f;
char fn[MAXPGPATH];
@@ -50,16 +55,17 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir,
XLogSegNo segno;
XLByteToSeg(startpoint, segno);
- XLogFileName(namebuf, timeline, segno);
+ XLogFileName(current_walfile_name, timeline, segno);
- snprintf(fn, sizeof(fn), "%s/%s.partial", basedir, namebuf);
+ snprintf(fn, sizeof(fn), "%s/%s%s", basedir, current_walfile_name,
+ partial_suffix ? partial_suffix : "");
f = open(fn, O_WRONLY | O_CREAT | PG_BINARY, S_IRUSR | S_IWUSR);
if (f == -1)
{
fprintf(stderr,
_("%s: could not open transaction log file \"%s\": %s\n"),
progname, fn, strerror(errno));
- return -1;
+ return false;
}
/*
@@ -72,17 +78,21 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir,
_("%s: could not stat transaction log file \"%s\": %s\n"),
progname, fn, strerror(errno));
close(f);
- return -1;
+ return false;
}
if (statbuf.st_size == XLogSegSize)
- return f; /* File is open and ready to use */
+ {
+ /* File is open and ready to use */
+ walfile = f;
+ return true;
+ }
if (statbuf.st_size != 0)
{
fprintf(stderr,
_("%s: transaction log file \"%s\" has %d bytes, should be 0 or %d\n"),
progname, fn, (int) statbuf.st_size, XLogSegSize);
close(f);
- return -1;
+ return false;
}
/* New, empty, file. So pad it to 16Mb with zeroes */
@@ -97,7 +107,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir,
free(zerobuf);
close(f);
unlink(fn);
- return -1;
+ return false;
}
}
free(zerobuf);
@@ -108,42 +118,45 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir,
_("%s: could not seek to beginning of transaction log file \"%s\": %s\n"),
progname, fn, strerror(errno));
close(f);
- return -1;
+ return false;
}
- return f;
+ walfile = f;
+ return true;
}
/*
- * Close the current WAL file, and rename it to the correct filename if it's
- * complete.
- *
- * If segment_complete is true, rename the current WAL file even if we've not
- * completed writing the whole segment.
+ * Close the current WAL file (if open), and rename it to the correct
+ * filename if it's complete. On failure, prints an error message to stderr
+ * and returns false, otherwise returns true.
*/
static bool
-close_walfile(char *basedir, char *walname, bool segment_complete)
+close_walfile(char *basedir, char *partial_suffix)
{
- off_t currpos = lseek(walfile, 0, SEEK_CUR);
+ off_t currpos;
+
+ if (walfile == -1)
+ return true;
+ currpos = lseek(walfile, 0, SEEK_CUR);
if (currpos == -1)
{
fprintf(stderr,
_("%s: could not determine seek position in file \"%s\": %s\n"),
- progname, walname, strerror(errno));
+ progname, current_walfile_name, strerror(errno));
return false;
}
if (fsync(walfile) != 0)
{
fprintf(stderr, _("%s: could not fsync file \"%s\": %s\n"),
- progname, walname, strerror(errno));
+ progname, current_walfile_name, strerror(errno));
return false;
}
if (close(walfile) != 0)
{
fprintf(stderr, _("%s: could not close file \"%s\": %s\n"),
- progname, walname, strerror(errno));
+ progname, current_walfile_name, strerror(errno));
walfile = -1;
return false;
}
@@ -153,24 +166,24 @@ close_walfile(char *basedir, char *walname, bool segment_complete)
* Rename the .partial file only if we've completed writing the whole
* segment or segment_complete is true.
*/
- if (currpos == XLOG_SEG_SIZE || segment_complete)
+ if (currpos == XLOG_SEG_SIZE && partial_suffix)
{
char oldfn[MAXPGPATH];
char newfn[MAXPGPATH];
- snprintf(oldfn, sizeof(oldfn), "%s/%s.partial", basedir, walname);
- snprintf(newfn, sizeof(newfn), "%s/%s", basedir, walname);
+ snprintf(oldfn, sizeof(oldfn), "%s/%s%s", basedir, current_walfile_name, partial_suffix);
+ snprintf(newfn, sizeof(newfn), "%s/%s", basedir, current_walfile_name);
if (rename(oldfn, newfn) != 0)
{
fprintf(stderr, _("%s: could not rename file \"%s\": %s\n"),
- progname, walname, strerror(errno));
+ progname, current_walfile_name, strerror(errno));
return false;
}
}
- else
+ else if (partial_suffix)
fprintf(stderr,
- _("%s: not renaming \"%s\", segment is not complete\n"),
- progname, walname);
+ _("%s: not renaming \"%s%s\", segment is not complete\n"),
+ progname, current_walfile_name, partial_suffix);
return true;
}
@@ -234,6 +247,123 @@ localTimestampDifferenceExceeds(int64 start_time,
}
/*
+ * Check if a timeline history file exists.
+ */
+static bool
+existsTimeLineHistoryFile(char *basedir, TimeLineID tli)
+{
+ char path[MAXPGPATH];
+ char histfname[MAXFNAMELEN];
+ int fd;
+
+ /*
+ * Timeline 1 never has a history file. We treat that as if it existed,
+ * since we never need to stream it.
+ */
+ if (tli == 1)
+ return true;
+
+ TLHistoryFileName(histfname, tli);
+
+ snprintf(path, sizeof(path), "%s/%s", basedir, histfname);
+
+ fd = open(path, O_RDONLY | PG_BINARY, 0);
+ if (fd < 0)
+ {
+ if (errno != ENOENT)
+ fprintf(stderr, _("%s: could not open timeline history file \"%s\": %s"),
+ progname, path, strerror(errno));
+ return false;
+ }
+ else
+ {
+ close(fd);
+ return true;
+ }
+}
+
+static bool
+writeTimeLineHistoryFile(char *basedir, TimeLineID tli, char *filename, char *content)
+{
+ int size = strlen(content);
+ char path[MAXPGPATH];
+ char tmppath[MAXPGPATH];
+ char histfname[MAXFNAMELEN];
+ int fd;
+
+ /*
+ * Check that the server's idea of how timeline history files should be
+ * named matches ours.
+ */
+ TLHistoryFileName(histfname, tli);
+ if (strcmp(histfname, filename) != 0)
+ {
+ fprintf(stderr, _("%s: server reported unexpected history file name for timeline %u: %s"),
+ progname, tli, filename);
+ return false;
+ }
+
+ /*
+ * Write into a temp file name.
+ */
+ snprintf(tmppath, MAXPGPATH, "%s.tmp", path);
+
+ unlink(tmppath);
+
+ fd = open(tmppath, O_WRONLY | O_CREAT | PG_BINARY, S_IRUSR | S_IWUSR);
+ if (fd < 0)
+ {
+ fprintf(stderr, _("%s: could not create timeline history file \"%s\": %s"),
+ progname, tmppath, strerror(errno));
+ return false;
+ }
+
+ errno = 0;
+ if ((int) write(fd, content, size) != size)
+ {
+ int save_errno = errno;
+
+ /*
+ * If we fail to make the file, delete it to release disk space
+ */
+ unlink(tmppath);
+ errno = save_errno;
+
+ fprintf(stderr, _("%s: could not write timeline history file \"%s\": %s"),
+ progname, tmppath, strerror(errno));
+ return false;
+ }
+
+ if (fsync(fd) != 0)
+ {
+ fprintf(stderr, _("%s: could not fsync file \"%s\": %s\n"),
+ progname, tmppath, strerror(errno));
+ return false;
+ }
+
+ if (close(fd) != 0)
+ {
+ fprintf(stderr, _("%s: could not close file \"%s\": %s\n"),
+ progname, tmppath, strerror(errno));
+ return false;
+ }
+
+ /*
+ * Now move the completed history file into place with its final name.
+ */
+
+ snprintf(path, sizeof(path), "%s/%s", basedir, histfname);
+ if (rename(tmppath, path) < 0)
+ {
+ fprintf(stderr, _("%s: could not rename file \"%s\" to \"%s\": %s\n"),
+ progname, tmppath, path, strerror(errno));
+ return false;
+ }
+
+ return true;
+}
+
+/*
* Converts an int64 to network byte order.
*/
static void
@@ -314,7 +444,8 @@ sendFeedback(PGconn *conn, XLogRecPtr blockpos, int64 now, bool replyRequested)
* (by sending an extra IDENTIFY_SYSTEM command)
*
* All received segments will be written to the directory
- * specified by basedir.
+ * specified by basedir. This will also fetch any missing timeline history
+ * files.
*
* The stream_stop callback will be called every time data
* is received, and whenever a segment is completed. If it returns
@@ -327,20 +458,22 @@ sendFeedback(PGconn *conn, XLogRecPtr blockpos, int64 now, bool replyRequested)
* This message will only contain the write location, and never
* flush or replay.
*
+ * If 'partial_suffix' is not NULL, files are initially created with the
+ * given suffix, and the suffix is removed once the file is finished. That
+ * allows you to tell the difference between partial and completed files,
+ * so that you can continue later where you left.
+ *
* Note: The log position *must* be at a log segment start!
*/
bool
ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
char *sysidentifier, char *basedir,
stream_stop_callback stream_stop,
- int standby_message_timeout, bool rename_partial)
+ int standby_message_timeout, char *partial_suffix)
{
char query[128];
- char current_walfile_name[MAXPGPATH];
PGresult *res;
- char *copybuf = NULL;
- int64 last_status = -1;
- XLogRecPtr blockpos = InvalidXLogRecPtr;
+ XLogRecPtr stoppos;
/*
* The message format used in streaming replication changed in 9.3, so we
@@ -359,7 +492,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
if (sysidentifier != NULL)
{
- /* Validate system identifier and timeline hasn't changed */
+ /* Validate system identifier hasn't changed */
res = PQexec(conn, "IDENTIFY_SYSTEM");
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
@@ -385,33 +518,184 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
PQclear(res);
return false;
}
- if (timeline != atoi(PQgetvalue(res, 0, 1)))
+ if (timeline > atoi(PQgetvalue(res, 0, 1)))
{
fprintf(stderr,
- _("%s: timeline does not match between base backup and streaming connection\n"),
- progname);
+ _("%s: starting timeline %u is not present in the server\n"),
+ progname, timeline);
PQclear(res);
return false;
}
PQclear(res);
}
- /* Initiate the replication stream at specified location */
- snprintf(query, sizeof(query), "START_REPLICATION %X/%X",
- (uint32) (startpos >> 32), (uint32) startpos);
- res = PQexec(conn, query);
- if (PQresultStatus(res) != PGRES_COPY_BOTH)
+ while (1)
{
- fprintf(stderr, _("%s: could not send replication command \"%s\": %s"),
- progname, "START_REPLICATION", PQresultErrorMessage(res));
+ /*
+ * Fetch the timeline history file for this timeline, if we don't
+ * have it already.
+ */
+ if (!existsTimeLineHistoryFile(basedir, timeline))
+ {
+ snprintf(query, sizeof(query), "TIMELINE_HISTORY %u", timeline);
+ res = PQexec(conn, query);
+ if (PQresultStatus(res) != PGRES_TUPLES_OK)
+ {
+ /* FIXME: we might send it ok, but get an error */
+ fprintf(stderr, _("%s: could not send replication command \"%s\": %s"),
+ progname, "TIMELINE_HISTORY", PQresultErrorMessage(res));
+ PQclear(res);
+ return false;
+ }
+
+ /*
+ * The response to TIMELINE_HISTORY is a single row result set
+ * with two fields: filename and content
+ */
+ if (PQnfields(res) != 2 || PQntuples(res) != 1)
+ {
+ fprintf(stderr,
+ _("%s: unexpected response to TIMELINE_HISTORY command: got %d rows and %d fields, expected %d rows and %d fields\n"),
+ progname, PQntuples(res), PQnfields(res), 1, 2);
+ }
+
+ /* Write the history file to disk */
+ writeTimeLineHistoryFile(basedir, timeline,
+ PQgetvalue(res, 0, 0),
+ PQgetvalue(res, 0, 1));
+
+ PQclear(res);
+ }
+
+ /*
+ * Before we start streaming from the requested location, check
+ * if the callback tells us to stop here.
+ */
+ if (stream_stop(startpos, timeline, false))
+ return true;
+
+ /* Initiate the replication stream at specified location */
+ snprintf(query, sizeof(query), "START_REPLICATION %X/%X TIMELINE %u",
+ (uint32) (startpos >> 32), (uint32) startpos,
+ timeline);
+ res = PQexec(conn, query);
+ if (PQresultStatus(res) != PGRES_COPY_BOTH)
+ {
+ fprintf(stderr, _("%s: could not send replication command \"%s\": %s"),
+ progname, "START_REPLICATION", PQresultErrorMessage(res));
+ PQclear(res);
+ return false;
+ }
PQclear(res);
- return false;
+
+ /* Stream the WAL */
+ if (!HandleCopyStream(conn, startpos, timeline, basedir, stream_stop,
+ standby_message_timeout, partial_suffix,
+ &stoppos))
+ goto error;
+
+ /*
+ * Streaming finished.
+ *
+ * There are two possible reasons for that: a controlled shutdown,
+ * or we reached the end of the current timeline. In case of
+ * end-of-timeline, the server sends a result set after Copy has
+ * finished, containing the next timeline's ID. Read that, and
+ * restart streaming from the next timeline.
+ */
+
+ res = PQgetResult(conn);
+ if (PQresultStatus(res) == PGRES_TUPLES_OK)
+ {
+ /*
+ * End-of-timeline. Read the next timeline's ID.
+ */
+ uint32 newtimeline;
+
+ newtimeline = atoi(PQgetvalue(res, 0, 0));
+ PQclear(res);
+
+ if (newtimeline <= timeline)
+ {
+ /* shouldn't happen */
+ fprintf(stderr,
+ "server reported unexpected next timeline %u, following timeline %u\n",
+ newtimeline, timeline);
+ goto error;
+ }
+
+ /* Read the final result, which should be CommandComplete. */
+ res = PQgetResult(conn);
+ if (PQresultStatus(res) != PGRES_COMMAND_OK)
+ {
+ fprintf(stderr,
+ _("%s: unexpected termination of replication stream: %s"),
+ progname, PQresultErrorMessage(res));
+ goto error;
+ }
+ PQclear(res);
+
+ /*
+ * Loop back to start streaming from the new timeline.
+ * Always start streaming at the beginning of a segment.
+ */
+ timeline = newtimeline;
+ startpos = stoppos - (stoppos % XLOG_SEG_SIZE);
+ continue;
+ }
+ else if (PQresultStatus(res) == PGRES_COMMAND_OK)
+ {
+ /*
+ * End of replication (ie. controlled shut down of the server).
+ *
+ * Check if the callback thinks it's OK to stop here. If not,
+ * complain.
+ */
+ if (stream_stop(stoppos, timeline, false))
+ return true;
+ else
+ {
+ fprintf(stderr, _("%s: replication stream was terminated before stop point\n"),
+ progname);
+ goto error;
+ }
+ }
+ else
+ {
+ /* Server returned an error. */
+ fprintf(stderr,
+ _("%s: unexpected termination of replication stream: %s"),
+ progname, PQresultErrorMessage(res));
+ goto error;
+ }
}
- PQclear(res);
- /*
- * Receive the actual xlog data
- */
+error:
+ if (walfile != -1 && close(walfile) != 0)
+ fprintf(stderr, _("%s: could not close file \"%s\": %s\n"),
+ progname, current_walfile_name, strerror(errno));
+ walfile = -1;
+ return false;
+}
+
+/*
+ * The main loop of ReceiveXLogStream. Handles the COPY stream after
+ * initiating streaming with the START_STREAMING command.
+ *
+ * If the COPY ends normally, returns true and sets *stoppos to the last
+ * byte written. On error, returns false.
+ */
+static bool
+HandleCopyStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
+ char *basedir, stream_stop_callback stream_stop,
+ int standby_message_timeout, char *partial_suffix,
+ XLogRecPtr *stoppos)
+{
+ char *copybuf = NULL;
+ int64 last_status = -1;
+ XLogRecPtr blockpos = startpos;
+ bool still_sending = true;
+
while (1)
{
int r;
@@ -430,20 +714,27 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
/*
* Check if we should continue streaming, or abort at this point.
*/
- if (stream_stop && stream_stop(blockpos, timeline, false))
+ if (still_sending && stream_stop(blockpos, timeline, false))
{
- if (walfile != -1 && !close_walfile(basedir, current_walfile_name,
- rename_partial))
+ if (!close_walfile(basedir, partial_suffix))
+ {
/* Potential error message is written by close_walfile */
goto error;
- return true;
+ }
+ if (PQputCopyEnd(conn, NULL) <= 0 || PQflush(conn))
+ {
+ fprintf(stderr, _("%s: could not send copy-end packet: %s"),
+ progname, PQerrorMessage(conn));
+ goto error;
+ }
+ still_sending = false;
}
/*
* Potentially send a status message to the master
*/
now = localGetCurrentTimestamp();
- if (standby_message_timeout > 0 &&
+ if (still_sending && standby_message_timeout > 0 &&
localTimestampDifferenceExceeds(last_status, now,
standby_message_timeout))
{
@@ -457,9 +748,8 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
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.
+ * No data available. Wait for some to appear, but not longer
+ * than the specified timeout, so that we can ping the server.
*/
fd_set input_mask;
struct timeval timeout;
@@ -467,7 +757,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
FD_ZERO(&input_mask);
FD_SET(PQsocket(conn), &input_mask);
- if (standby_message_timeout)
+ if (standby_message_timeout && still_sending)
{
int64 targettime;
long secs;
@@ -493,8 +783,8 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
{
/*
* Got a timeout or signal. Continue the loop and either
- * deliver a status packet to the server or just go back into
- * blocking.
+ * deliver a status packet to the server or just go back
+ * into blocking.
*/
continue;
}
@@ -515,8 +805,31 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
continue;
}
if (r == -1)
- /* End of copy stream */
- break;
+ {
+ /*
+ * The server closed its end of the copy stream. Close ours
+ * if we haven't done so already, and exit.
+ */
+ if (still_sending)
+ {
+ if (!close_walfile(basedir, partial_suffix))
+ {
+ /* Error message written in close_walfile() */
+ goto error;
+ }
+ if (PQputCopyEnd(conn, NULL) <= 0 || PQflush(conn))
+ {
+ fprintf(stderr, _("%s: could not send copy-end packet: %s"),
+ progname, PQerrorMessage(conn));
+ goto error;
+ }
+ still_sending = false;
+ }
+ if (copybuf != NULL)
+ PQfreemem(copybuf);
+ *stoppos = blockpos;
+ return true;
+ }
if (r == -2)
{
fprintf(stderr, _("%s: could not read COPY data: %s"),
@@ -548,174 +861,148 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline,
replyRequested = copybuf[pos];
/* If the server requested an immediate reply, send one. */
- if (replyRequested)
+ if (replyRequested && still_sending)
{
now = localGetCurrentTimestamp();
if (!sendFeedback(conn, blockpos, now, false))
goto error;
last_status = now;
}
- continue;
}
- else if (copybuf[0] != 'w')
- {
- fprintf(stderr, _("%s: unrecognized streaming header: \"%c\"\n"),
- progname, 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)
+ else if (copybuf[0] == 'w')
{
- fprintf(stderr, _("%s: streaming header too small: %d\n"),
- progname, r);
- goto error;
- }
- blockpos = recvint64(&copybuf[1]);
-
- /* Extract WAL location for this block */
- xlogoff = blockpos % XLOG_SEG_SIZE;
+ /*
+ * Once we've decided we don't want to receive any more, just
+ * ignore any subsequent XLogData messages.
+ */
+ if (!still_sending)
+ continue;
- /*
- * Verify that the initial location in the stream matches where we
- * think we are.
- */
- if (walfile == -1)
- {
- /* No file open yet */
- if (xlogoff != 0)
- {
- fprintf(stderr,
- _("%s: received transaction log record for offset %u with no file open\n"),
- progname, xlogoff);
- goto error;
- }
- }
- else
- {
- /* More data in existing segment */
- /* XXX: store seek value don't reseek all the time */
- if (lseek(walfile, 0, SEEK_CUR) != xlogoff)
+ /*
+ * 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)
{
- fprintf(stderr,
- _("%s: got WAL data offset %08x, expected %08x\n"),
- progname, xlogoff, (int) lseek(walfile, 0, SEEK_CUR));
+ fprintf(stderr, _("%s: streaming header too small: %d\n"),
+ progname, r);
goto error;
}
- }
-
- bytes_left = r - hdr_len;
- bytes_written = 0;
+ blockpos = recvint64(&copybuf[1]);
- while (bytes_left)
- {
- int bytes_to_write;
+ /* Extract WAL location for this block */
+ xlogoff = blockpos % XLOG_SEG_SIZE;
/*
- * If crossing a WAL boundary, only write up until we reach
- * XLOG_SEG_SIZE.
+ * Verify that the initial location in the stream matches where
+ * we think we are.
*/
- if (xlogoff + bytes_left > XLOG_SEG_SIZE)
- bytes_to_write = XLOG_SEG_SIZE - xlogoff;
- else
- bytes_to_write = bytes_left;
-
if (walfile == -1)
{
- walfile = open_walfile(blockpos, timeline,
- basedir, current_walfile_name);
- if (walfile == -1)
- /* Error logged by open_walfile */
+ /* No file open yet */
+ if (xlogoff != 0)
+ {
+ fprintf(stderr,
+ _("%s: received transaction log record for offset %u with no file open\n"),
+ progname, xlogoff);
goto error;
+ }
}
-
- if (write(walfile,
- copybuf + hdr_len + bytes_written,
- bytes_to_write) != bytes_to_write)
+ else
{
- fprintf(stderr,
- _("%s: could not write %u bytes to WAL file \"%s\": %s\n"),
- progname, bytes_to_write, current_walfile_name,
- strerror(errno));
- goto error;
+ /* More data in existing segment */
+ /* XXX: store seek value don't reseek all the time */
+ if (lseek(walfile, 0, SEEK_CUR) != xlogoff)
+ {
+ fprintf(stderr,
+ _("%s: got WAL data offset %08x, expected %08x\n"),
+ progname, xlogoff, (int) lseek(walfile, 0, SEEK_CUR));
+ goto error;
+ }
}
- /* Write was successful, advance our position */
- bytes_written += bytes_to_write;
- bytes_left -= bytes_to_write;
- blockpos += bytes_to_write;
- xlogoff += bytes_to_write;
+ bytes_left = r - hdr_len;
+ bytes_written = 0;
- /* Did we reach the end of a WAL segment? */
- if (blockpos % XLOG_SEG_SIZE == 0)
+ while (bytes_left)
{
- if (!close_walfile(basedir, current_walfile_name, false))
- /* Error message written in close_walfile() */
- goto error;
+ int bytes_to_write;
- xlogoff = 0;
+ /*
+ * If crossing a WAL boundary, only write up until we reach
+ * XLOG_SEG_SIZE.
+ */
+ if (xlogoff + bytes_left > XLOG_SEG_SIZE)
+ bytes_to_write = XLOG_SEG_SIZE - xlogoff;
+ else
+ bytes_to_write = bytes_left;
- if (stream_stop != NULL)
+ if (walfile == -1)
{
- /*
- * Callback when the segment finished, and return if it
- * told us to.
- */
- if (stream_stop(blockpos, timeline, true))
- return true;
+ if (!open_walfile(blockpos, timeline,
+ basedir, partial_suffix))
+ {
+ /* Error logged by open_walfile */
+ goto error;
+ }
}
- }
- }
- /* No more data left to write, start receiving next copy packet */
- }
- /*
- * The only way to get out of the loop is if the server shut down the
- * replication stream. If it's a controlled shutdown, the server will send
- * a shutdown message, and we'll return the latest xlog location that has
- * been streamed.
- */
+ if (write(walfile,
+ copybuf + hdr_len + bytes_written,
+ bytes_to_write) != bytes_to_write)
+ {
+ fprintf(stderr,
+ _("%s: could not write %u bytes to WAL file \"%s\": %s\n"),
+ progname, bytes_to_write, current_walfile_name,
+ strerror(errno));
+ goto error;
+ }
- res = PQgetResult(conn);
- if (PQresultStatus(res) != PGRES_COMMAND_OK)
- {
- fprintf(stderr,
- _("%s: unexpected termination of replication stream: %s"),
- progname, PQresultErrorMessage(res));
- goto error;
- }
- PQclear(res);
+ /* Write was successful, advance our position */
+ bytes_written += bytes_to_write;
+ bytes_left -= bytes_to_write;
+ blockpos += bytes_to_write;
+ xlogoff += bytes_to_write;
- /* Complain if we've not reached stop point yet */
- if (stream_stop != NULL && !stream_stop(blockpos, timeline, false))
- {
- fprintf(stderr, _("%s: replication stream was terminated before stop point\n"),
- progname);
- goto error;
+ /* Did we reach the end of a WAL segment? */
+ if (blockpos % XLOG_SEG_SIZE == 0)
+ {
+ if (!close_walfile(basedir, partial_suffix))
+ /* Error message written in close_walfile() */
+ goto error;
+
+ xlogoff = 0;
+
+ if (still_sending && stream_stop(blockpos, timeline, false))
+ {
+ if (PQputCopyEnd(conn, NULL) <= 0 || PQflush(conn))
+ {
+ fprintf(stderr, _("%s: could not send copy-end packet: %s"),
+ progname, PQerrorMessage(conn));
+ goto error;
+ }
+ still_sending = false;
+ break; /* ignore the rest of this XLogData packet */
+ }
+ }
+ }
+ /* No more data left to write, receive next copy packet */
+ }
+ else
+ {
+ fprintf(stderr, _("%s: unrecognized streaming header: \"%c\"\n"),
+ progname, copybuf[0]);
+ goto error;
+ }
}
- if (copybuf != NULL)
- PQfreemem(copybuf);
- if (walfile != -1 && close(walfile) != 0)
- fprintf(stderr, _("%s: could not close file \"%s\": %s\n"),
- progname, current_walfile_name, strerror(errno));
- walfile = -1;
- return true;
-
error:
if (copybuf != NULL)
PQfreemem(copybuf);
- if (walfile != -1 && close(walfile) != 0)
- fprintf(stderr, _("%s: could not close file \"%s\": %s\n"),
- progname, current_walfile_name, strerror(errno));
- walfile = -1;
return false;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-05 09:44:27 +0000