Refactor new file permission handling

The file handling functions from fd.c were called with a diverse mix of
notations for the file permissions when they were opening new files.
Almost all files created by the server should have the same permissions
set.  So change the API so that e.g. OpenTransientFile() automatically
uses the standard permissions set, and OpenTransientFilePerm() is a new
function that takes an explicit permissions set for the few cases where
it is needed.  This also saves an unnecessary argument for call sites
that are just opening an existing file.

While we're reviewing these APIs, get rid of the FileName typedef and
use the standard const char * for the file name and mode_t for the file
mode.  This makes these functions match other file handling functions
and removes an unnecessary layer of mysteriousness.  We can also get rid
of a few casts that way.

Author: David Steele <david@pgmasters.net>

6 files changed, 22 insertions, 36 deletions

diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index bd560e47e19..f93c194e182 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -1013,8 +1013,7 @@ logical_rewrite_log_mapping(RewriteState state, TransactionId xid,
 		src->off = 0;
 		memcpy(src->path, path, sizeof(path));
 		src->vfd = PathNameOpenFile(path,
-									O_CREAT | O_EXCL | O_WRONLY | PG_BINARY,
-									S_IRUSR | S_IWUSR);
+									O_CREAT | O_EXCL | O_WRONLY | PG_BINARY);
 		if (src->vfd < 0)
 			ereport(ERROR,
 					(errcode_for_file_access(),
@@ -1133,8 +1132,7 @@ heap_xlog_logical_rewrite(XLogReaderState *r)
 			 xlrec->mapped_xid, XLogRecGetXid(r));
 
 	fd = OpenTransientFile(path,
-						   O_CREAT | O_WRONLY | PG_BINARY,
-						   S_IRUSR | S_IWUSR);
+						   O_CREAT | O_WRONLY | PG_BINARY);
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -1258,7 +1256,7 @@ CheckPointLogicalRewriteHeap(void)
 		}
 		else
 		{
-			int			fd = OpenTransientFile(path, O_RDONLY | PG_BINARY, 0);
+			int			fd = OpenTransientFile(path, O_RDONLY | PG_BINARY);
 
 			/*
 			 * The file cannot vanish due to concurrency since this function
diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index 77edc51e1c9..9dd77190ec8 100644
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -599,7 +599,7 @@ SimpleLruDoesPhysicalPageExist(SlruCtl ctl, int pageno)
 
 	SlruFileName(ctl, path, segno);
 
-	fd = OpenTransientFile(path, O_RDWR | PG_BINARY, S_IRUSR | S_IWUSR);
+	fd = OpenTransientFile(path, O_RDWR | PG_BINARY);
 	if (fd < 0)
 	{
 		/* expected: file doesn't exist */
@@ -654,7 +654,7 @@ SlruPhysicalReadPage(SlruCtl ctl, int pageno, int slotno)
 	 * SlruPhysicalWritePage).  Hence, if we are InRecovery, allow the case
 	 * where the file doesn't exist, and return zeroes instead.
 	 */
-	fd = OpenTransientFile(path, O_RDWR | PG_BINARY, S_IRUSR | S_IWUSR);
+	fd = OpenTransientFile(path, O_RDWR | PG_BINARY);
 	if (fd < 0)
 	{
 		if (errno != ENOENT || !InRecovery)
@@ -804,8 +804,7 @@ SlruPhysicalWritePage(SlruCtl ctl, int pageno, int slotno, SlruFlush fdata)
 		 * don't use O_EXCL or O_TRUNC or anything like that.
 		 */
 		SlruFileName(ctl, path, segno);
-		fd = OpenTransientFile(path, O_RDWR | O_CREAT | PG_BINARY,
-							   S_IRUSR | S_IWUSR);
+		fd = OpenTransientFile(path, O_RDWR | O_CREAT | PG_BINARY);
 		if (fd < 0)
 		{
 			slru_errcause = SLRU_OPEN_FAILED;
diff --git a/src/backend/access/transam/timeline.c b/src/backend/access/transam/timeline.c
index 63db8a981dc..3d65e5624ad 100644
--- a/src/backend/access/transam/timeline.c
+++ b/src/backend/access/transam/timeline.c
@@ -307,8 +307,7 @@ writeTimeLineHistory(TimeLineID newTLI, TimeLineID parentTLI,
 	unlink(tmppath);
 
 	/* do not use get_sync_bit() here --- want to fsync only at end of fill */
-	fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL,
-						   S_IRUSR | S_IWUSR);
+	fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL);
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -325,7 +324,7 @@ writeTimeLineHistory(TimeLineID newTLI, TimeLineID parentTLI,
 	else
 		TLHistoryFilePath(path, parentTLI);
 
-	srcfd = OpenTransientFile(path, O_RDONLY, 0);
+	srcfd = OpenTransientFile(path, O_RDONLY);
 	if (srcfd < 0)
 	{
 		if (errno != ENOENT)
@@ -459,8 +458,7 @@ writeTimeLineHistoryFile(TimeLineID tli, char *content, int size)
 	unlink(tmppath);
 
 	/* do not use get_sync_bit() here --- want to fsync only at end of fill */
-	fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL,
-						   S_IRUSR | S_IWUSR);
+	fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL);
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index bfd800bc16b..cfaf8da7812 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -1195,7 +1195,7 @@ ReadTwoPhaseFile(TransactionId xid, bool give_warnings)
 
 	TwoPhaseFilePath(path, xid);
 
-	fd = OpenTransientFile(path, O_RDONLY | PG_BINARY, 0);
+	fd = OpenTransientFile(path, O_RDONLY | PG_BINARY);
 	if (fd < 0)
 	{
 		if (give_warnings)
@@ -1581,8 +1581,7 @@ RecreateTwoPhaseFile(TransactionId xid, void *content, int len)
 	TwoPhaseFilePath(path, xid);
 
 	fd = OpenTransientFile(path,
-						   O_CREAT | O_TRUNC | O_WRONLY | PG_BINARY,
-						   S_IRUSR | S_IWUSR);
+						   O_CREAT | O_TRUNC | O_WRONLY | PG_BINARY);
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 051347163b5..dd028a12a40 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -3185,8 +3185,7 @@ XLogFileInit(XLogSegNo logsegno, bool *use_existent, bool use_lock)
 	 */
 	if (*use_existent)
 	{
-		fd = BasicOpenFile(path, O_RDWR | PG_BINARY | get_sync_bit(sync_method),
-						   S_IRUSR | S_IWUSR);
+		fd = BasicOpenFile(path, O_RDWR | PG_BINARY | get_sync_bit(sync_method));
 		if (fd < 0)
 		{
 			if (errno != ENOENT)
@@ -3211,8 +3210,7 @@ XLogFileInit(XLogSegNo logsegno, bool *use_existent, bool use_lock)
 	unlink(tmppath);
 
 	/* do not use get_sync_bit() here --- want to fsync only at end of fill */
-	fd = BasicOpenFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
-					   S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY);
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -3308,8 +3306,7 @@ XLogFileInit(XLogSegNo logsegno, bool *use_existent, bool use_lock)
 	*use_existent = false;
 
 	/* Now open original target segment (might not be file I just made) */
-	fd = BasicOpenFile(path, O_RDWR | PG_BINARY | get_sync_bit(sync_method),
-					   S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(path, O_RDWR | PG_BINARY | get_sync_bit(sync_method));
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -3350,7 +3347,7 @@ XLogFileCopy(XLogSegNo destsegno, TimeLineID srcTLI, XLogSegNo srcsegno,
 	 * Open the source file
 	 */
 	XLogFilePath(path, srcTLI, srcsegno, wal_segment_size);
-	srcfd = OpenTransientFile(path, O_RDONLY | PG_BINARY, 0);
+	srcfd = OpenTransientFile(path, O_RDONLY | PG_BINARY);
 	if (srcfd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -3364,8 +3361,7 @@ XLogFileCopy(XLogSegNo destsegno, TimeLineID srcTLI, XLogSegNo srcsegno,
 	unlink(tmppath);
 
 	/* do not use get_sync_bit() here --- want to fsync only at end of fill */
-	fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
-						   S_IRUSR | S_IWUSR);
+	fd = OpenTransientFile(tmppath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY);
 	if (fd < 0)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -3543,8 +3539,7 @@ XLogFileOpen(XLogSegNo segno)
 
 	XLogFilePath(path, ThisTimeLineID, segno, wal_segment_size);
 
-	fd = BasicOpenFile(path, O_RDWR | PG_BINARY | get_sync_bit(sync_method),
-					   S_IRUSR | S_IWUSR);
+	fd = BasicOpenFile(path, O_RDWR | PG_BINARY | get_sync_bit(sync_method));
 	if (fd < 0)
 		ereport(PANIC,
 				(errcode_for_file_access(),
@@ -3610,7 +3605,7 @@ XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli,
 		snprintf(path, MAXPGPATH, XLOGDIR "/%s", xlogfname);
 	}
 
-	fd = BasicOpenFile(path, O_RDONLY | PG_BINARY, 0);
+	fd = BasicOpenFile(path, O_RDONLY | PG_BINARY);
 	if (fd >= 0)
 	{
 		/* Success! */
@@ -4449,8 +4444,7 @@ WriteControlFile(void)
 	memcpy(buffer, ControlFile, sizeof(ControlFileData));
 
 	fd = BasicOpenFile(XLOG_CONTROL_FILE,
-					   O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
-					   S_IRUSR | S_IWUSR);
+					   O_RDWR | O_CREAT | O_EXCL | PG_BINARY);
 	if (fd < 0)
 		ereport(PANIC,
 				(errcode_for_file_access(),
@@ -4494,8 +4488,7 @@ ReadControlFile(void)
 	 * Read data...
 	 */
 	fd = BasicOpenFile(XLOG_CONTROL_FILE,
-					   O_RDWR | PG_BINARY,
-					   S_IRUSR | S_IWUSR);
+					   O_RDWR | PG_BINARY);
 	if (fd < 0)
 		ereport(PANIC,
 				(errcode_for_file_access(),
@@ -4695,8 +4688,7 @@ UpdateControlFile(void)
 	FIN_CRC32C(ControlFile->crc);
 
 	fd = BasicOpenFile(XLOG_CONTROL_FILE,
-					   O_RDWR | PG_BINARY,
-					   S_IRUSR | S_IWUSR);
+					   O_RDWR | PG_BINARY);
 	if (fd < 0)
 		ereport(PANIC,
 				(errcode_for_file_access(),
diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c
index b11c94c9b68..3af6e19c983 100644
--- a/src/backend/access/transam/xlogutils.c
+++ b/src/backend/access/transam/xlogutils.c
@@ -694,7 +694,7 @@ XLogRead(char *buf, int segsize, TimeLineID tli, XLogRecPtr startptr,
 
 			XLogFilePath(path, tli, sendSegNo, segsize);
 
-			sendFile = BasicOpenFile(path, O_RDONLY | PG_BINARY, 0);
+			sendFile = BasicOpenFile(path, O_RDONLY | PG_BINARY);
 
 			if (sendFile < 0)
 			{