Create an fd.c entry point that is just like plain open(2) except that

it will close VFDs if necessary to surmount ENFILE or EMFILE failures.
Make use of this in md.c, xlog.c, and user.c routines that were
formerly vulnerable to these failures.  In particular, this should
handle failures of mdblindwrt() that have been observed under heavy
load conditions.  (By golly, every other process on the system may
crash after Postgres eats up all the kernel FDs, but Postgres will
keep going!)

1 files changed, 12 insertions, 50 deletions

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index b672cf2c7a9..07a8392c4e4 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.13 2000/04/12 17:14:53 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.14 2000/06/02 03:58:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -44,8 +44,6 @@ bool		StopIfError = false;
 SPINLOCK	ControlFileLockId;
 SPINLOCK	XidGenLockId;
 
-extern bool ReleaseDataFile(void);
-
 extern VariableCache ShmemVariableCache;
 
 #define MinXLOGbuffers	4
@@ -738,22 +736,13 @@ XLogFileInit(uint32 log, uint32 seg)
 	XLogFileName(path, log, seg);
 	unlink(path);
 
-tryAgain:
 #ifndef __CYGWIN__
-	fd = open(path, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(path, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
 #else
-	fd = open(path, O_RDWR | O_CREAT | O_EXCL | O_BINARY, S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(path, O_RDWR | O_CREAT | O_EXCL | O_BINARY, S_IRUSR | S_IWUSR);
 #endif
-	if (fd < 0 && (errno == EMFILE || errno == ENFILE))
-	{
-		fd = errno;
-		if (!ReleaseDataFile())
-			elog(STOP, "Create(logfile %u seg %u) failed: %d (and no one data file can be closed)",
-				 logId, logSeg, fd);
-		goto tryAgain;
-	}
 	if (fd < 0)
-		elog(STOP, "Init(logfile %u seg %u) failed: %d",
+		elog(STOP, "Open(logfile %u seg %u) failed: %d",
 			 logId, logSeg, errno);
 
 	if (lseek(fd, XLogSegSize - 1, SEEK_SET) != (off_t) (XLogSegSize - 1))
@@ -783,20 +772,11 @@ XLogFileOpen(uint32 log, uint32 seg, bool econt)
 
 	XLogFileName(path, log, seg);
 
-tryAgain:
 #ifndef __CYGWIN__
-	fd = open(path, O_RDWR);
+	fd = BasicOpenFile(path, O_RDWR, S_IRUSR | S_IWUSR);
 #else
-	fd = open(path, O_RDWR | O_BINARY);
+	fd = BasicOpenFile(path, O_RDWR | O_BINARY, S_IRUSR | S_IWUSR);
 #endif
-	if (fd < 0 && (errno == EMFILE || errno == ENFILE))
-	{
-		fd = errno;
-		if (!ReleaseDataFile())
-			elog(STOP, "Open(logfile %u seg %u) failed: %d (and no one data file can be closed)",
-				 logId, logSeg, fd);
-		goto tryAgain;
-	}
 	if (fd < 0)
 	{
 		if (econt && errno == ENOENT)
@@ -1102,20 +1082,11 @@ UpdateControlFile()
 {
 	int			fd;
 
-tryAgain:
 #ifndef __CYGWIN__
-	fd = open(ControlFilePath, O_RDWR);
+	fd = BasicOpenFile(ControlFilePath, O_RDWR, S_IRUSR | S_IWUSR);
 #else
-	fd = open(ControlFilePath, O_RDWR | O_BINARY);
+	fd = BasicOpenFile(ControlFilePath, O_RDWR | O_BINARY, S_IRUSR | S_IWUSR);
 #endif
-	if (fd < 0 && (errno == EMFILE || errno == ENFILE))
-	{
-		fd = errno;
-		if (!ReleaseDataFile())
-			elog(STOP, "Open(cntlfile) failed: %d (and no one data file can be closed)",
-				 fd);
-		goto tryAgain;
-	}
 	if (fd < 0)
 		elog(STOP, "Open(cntlfile) failed: %d", errno);
 
@@ -1174,9 +1145,9 @@ BootStrapXLOG()
 #endif
 
 #ifndef __CYGWIN__
-	fd = open(ControlFilePath, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(ControlFilePath, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
 #else
-	fd = open(ControlFilePath, O_RDWR | O_CREAT | O_EXCL | O_BINARY, S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(ControlFilePath, O_RDWR | O_CREAT | O_EXCL | O_BINARY, S_IRUSR | S_IWUSR);
 #endif
 	if (fd < 0)
 		elog(STOP, "BootStrapXLOG failed to create control file (%s): %d",
@@ -1288,20 +1259,11 @@ StartupXLOG()
 	/*
 	 * Open/read Control file
 	 */
-tryAgain:
 #ifndef __CYGWIN__
-	fd = open(ControlFilePath, O_RDWR);
+	fd = BasicOpenFile(ControlFilePath, O_RDWR, S_IRUSR | S_IWUSR);
 #else
-	fd = open(ControlFilePath, O_RDWR | O_BINARY);
+	fd = BasicOpenFile(ControlFilePath, O_RDWR | O_BINARY, S_IRUSR | S_IWUSR);
 #endif
-	if (fd < 0 && (errno == EMFILE || errno == ENFILE))
-	{
-		fd = errno;
-		if (!ReleaseDataFile())
-			elog(STOP, "Open(\"%s\") failed: %d (and no one data file can be closed)",
-				 ControlFilePath, fd);
-		goto tryAgain;
-	}
 	if (fd < 0)
 		elog(STOP, "Open(\"%s\") failed: %d", ControlFilePath, errno);