Force archive_status of .done for xlogs created by dearchival/replication.

This is a forward-patch of commit 6f4b8a4f4f,
applied to 9.2 back in August. The plan was to do something else in master,
but it looks like it's not going to happen, so let's just apply the 9.2
solution to master as well.

Fujii Masao

src/backend/access/transam/xlogarchive.c

@@ -473,6 +473,12 @@ KeepFileRestoredFromArchive(char *path, char *xlogfname)
 				 errmsg("could not rename file \"%s\" to \"%s\": %m",
 						path, xlogfpath)));
 
+	/*
+	 * Create .done file forcibly to prevent the restored segment from
+	 * being archived again later.
+	 */
+	XLogArchiveForceDone(xlogfname);
+
 	/*
 	 * If the existing file was replaced, since walsenders might have it
 	 * open, request them to reload a currently-open segment. This is only
@@ -544,6 +550,59 @@ XLogArchiveNotifySeg(XLogSegNo segno)
 	XLogArchiveNotify(xlog);
 }
 
+/*
+ * XLogArchiveForceDone
+ *
+ * Emit notification forcibly that an XLOG segment file has been successfully
+ * archived, by creating <XLOG>.done regardless of whether <XLOG>.ready
+ * exists or not.
+ */
+void
+XLogArchiveForceDone(const char *xlog)
+{
+	char		archiveReady[MAXPGPATH];
+	char		archiveDone[MAXPGPATH];
+	struct stat stat_buf;
+	FILE	   *fd;
+
+	/* Exit if already known done */
+	StatusFilePath(archiveDone, xlog, ".done");
+	if (stat(archiveDone, &stat_buf) == 0)
+		return;
+
+	/* If .ready exists, rename it to .done */
+	StatusFilePath(archiveReady, xlog, ".ready");
+	if (stat(archiveReady, &stat_buf) == 0)
+	{
+		if (rename(archiveReady, archiveDone) < 0)
+			ereport(WARNING,
+					(errcode_for_file_access(),
+					 errmsg("could not rename file \"%s\" to \"%s\": %m",
+							archiveReady, archiveDone)));
+
+		return;
+	}
+
+	/* insert an otherwise empty file called <XLOG>.done */
+	fd = AllocateFile(archiveDone, "w");
+	if (fd == NULL)
+	{
+		ereport(LOG,
+				(errcode_for_file_access(),
+				 errmsg("could not create archive status file \"%s\": %m",
+						archiveDone)));
+		return;
+	}
+	if (FreeFile(fd))
+	{
+		ereport(LOG,
+				(errcode_for_file_access(),
+				 errmsg("could not write archive status file \"%s\": %m",
+						archiveDone)));
+		return;
+	}
+}
+
 /*
  * XLogArchiveCheckDone
  *

src/backend/replication/walreceiver.c

@@ -83,7 +83,7 @@ walrcv_disconnect_type walrcv_disconnect = NULL;
 /*
  * These variables are used similarly to openLogFile/SegNo/Off,
  * but for walreceiver to write the XLOG. recvFileTLI is the TimeLineID
- * corresponding the filename of recvFile, used for error messages.
+ * corresponding the filename of recvFile.
  */
 static int	recvFile = -1;
 static TimeLineID	recvFileTLI = 0;
@@ -528,12 +528,21 @@ WalReceiverMain(void)
 		 */
 		if (recvFile >= 0)
 		{
+			char		xlogfname[MAXFNAMELEN];
+
 			XLogWalRcvFlush(false);
 			if (close(recvFile) != 0)
 				ereport(PANIC,
 						(errcode_for_file_access(),
 						 errmsg("could not close log segment %s: %m",
 								XLogFileNameP(recvFileTLI, recvSegNo))));
+
+			/*
+			 * Create .done file forcibly to prevent the streamed segment from
+			 * being archived later.
+			 */
+			XLogFileName(xlogfname, recvFileTLI, recvSegNo);
+			XLogArchiveForceDone(xlogfname);
 		}
 		recvFile = -1;
 
@@ -865,6 +874,8 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
 			 */
 			if (recvFile >= 0)
 			{
+				char		xlogfname[MAXFNAMELEN];
+
 				XLogWalRcvFlush(false);
 
 				/*
@@ -877,6 +888,13 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
 							(errcode_for_file_access(),
 							 errmsg("could not close log segment %s: %m",
 									XLogFileNameP(recvFileTLI, recvSegNo))));
+
+				/*
+				 * Create .done file forcibly to prevent the streamed segment from
+				 * being archived later.
+				 */
+				XLogFileName(xlogfname, recvFileTLI, recvSegNo);
+				XLogArchiveForceDone(xlogfname);
 			}
 			recvFile = -1;
 

src/include/access/xlog_internal.h

@@ -278,6 +278,7 @@ extern void ExecuteRecoveryCommand(char *command, char *commandName,
 extern void KeepFileRestoredFromArchive(char  *path, char *xlogfname);
 extern void XLogArchiveNotify(const char *xlog);
 extern void XLogArchiveNotifySeg(XLogSegNo segno);
+extern void XLogArchiveForceDone(const char *xlog);
 extern bool XLogArchiveCheckDone(const char *xlog);
 extern bool XLogArchiveIsBusy(const char *xlog);
 extern void XLogArchiveCleanup(const char *xlog);