More janitorial work: remove the explicit casting of NULL literals to a

pointer type when it is not necessary to do so.

For future reference, casting NULL to a pointer type is only necessary
when (a) invoking a function AND either (b) the function has no prototype
OR (c) the function is a varargs function.

src/backend/storage/buffer/bufmgr.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.150 2003/12/20 22:18:02 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/buffer/bufmgr.c,v 1.151 2004/01/07 18:56:27 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -372,7 +372,7 @@ BufferAlloc(Relation reln,
 	 * it to disk. Remember to unlock BufMgrLock while doing the IOs.
 	 */
 	inProgress = FALSE;
-	for (buf = (BufferDesc *) NULL; buf == (BufferDesc *) NULL;)
+	for (buf = NULL; buf == NULL;)
 	{
 		buf = StrategyGetBuffer();
 
@@ -399,7 +399,7 @@ BufferAlloc(Relation reln,
 			if ((buf->flags & BM_IO_ERROR) != 0)
 			{
 				UnpinBuffer(buf);
-				buf = (BufferDesc *) NULL;
+				buf = NULL;
 				continue;
 			}
 
@@ -440,7 +440,7 @@ BufferAlloc(Relation reln,
 				buf->flags &= ~BM_IO_IN_PROGRESS;
 				TerminateBufferIO(buf);
 				UnpinBuffer(buf);
-				buf = (BufferDesc *) NULL;
+				buf = NULL;
 			}
 			else
 			{
@@ -476,7 +476,7 @@ BufferAlloc(Relation reln,
 				buf->flags &= ~BM_IO_IN_PROGRESS;
 				TerminateBufferIO(buf);
 				UnpinBuffer(buf);
-				buf = (BufferDesc *) NULL;
+				buf = NULL;
 			}
 
 			/*
@@ -799,7 +799,7 @@ BufferSync(int percent, int maxpages)
 		bufHdr->flags &= ~BM_JUST_DIRTIED;
 		LWLockRelease(BufMgrLock);
 
-		if (reln == (Relation) NULL)
+		if (reln == NULL)
 		{
 			status = smgrblindwrt(DEFAULT_SMGR,
 								  bufHdr->tag.rnode,
@@ -849,7 +849,7 @@ BufferSync(int percent, int maxpages)
 		LWLockRelease(BufMgrLock);
 
 		/* drop refcnt obtained by RelationNodeCacheGetRelation */
-		if (reln != (Relation) NULL)
+		if (reln != NULL)
 			RelationDecrementReferenceCount(reln);
 	}
 
@@ -1105,7 +1105,7 @@ BufferReplace(BufferDesc *bufHdr)
 
 	reln = RelationNodeCacheGetRelation(bufHdr->tag.rnode);
 
-	if (reln != (Relation) NULL)
+	if (reln != NULL)
 	{
 		status = smgrwrite(DEFAULT_SMGR, reln,
 						   bufHdr->tag.blockNum,
@@ -1119,7 +1119,7 @@ BufferReplace(BufferDesc *bufHdr)
 	}
 
 	/* drop relcache refcnt incremented by RelationNodeCacheGetRelation */
-	if (reln != (Relation) NULL)
+	if (reln != NULL)
 		RelationDecrementReferenceCount(reln);
 
 	/* Pop the error context stack */
@@ -1949,7 +1949,7 @@ LockBufferForCleanup(Buffer buffer)
  *	Note : We assume that nested buffer IO never occur.
  *	i.e at most one io_in_progress lock is held per proc.
 */
-static BufferDesc *InProgressBuf = (BufferDesc *) NULL;
+static BufferDesc *InProgressBuf = NULL;
 static bool IsForInput;
 
 /*
@@ -1991,7 +1991,7 @@ TerminateBufferIO(BufferDesc *buf)
 {
 	Assert(buf == InProgressBuf);
 	LWLockRelease(buf->io_in_progress_lock);
-	InProgressBuf = (BufferDesc *) NULL;
+	InProgressBuf = NULL;
 }
 
 /*
@@ -2016,7 +2016,7 @@ ContinueBufferIO(BufferDesc *buf, bool forInput)
 void
 InitBufferIO(void)
 {
-	InProgressBuf = (BufferDesc *) NULL;
+	InProgressBuf = NULL;
 }
 #endif
 

src/backend/storage/buffer/localbuf.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.50 2003/11/29 19:51:56 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/buffer/localbuf.c,v 1.51 2004/01/07 18:56:27 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -41,7 +41,7 @@ BufferDesc *
 LocalBufferAlloc(Relation reln, BlockNumber blockNum, bool *foundPtr)
 {
 	int			i;
-	BufferDesc *bufHdr = (BufferDesc *) NULL;
+	BufferDesc *bufHdr = NULL;
 
 	/* a low tech search for now -- not optimized for scans */
 	for (i = 0; i < NLocBuffer; i++)
@@ -93,7 +93,7 @@ LocalBufferAlloc(Relation reln, BlockNumber blockNum, bool *foundPtr)
 		Relation	bufrel = RelationNodeCacheGetRelation(bufHdr->tag.rnode);
 
 		/* flush this page */
-		if (bufrel == (Relation) NULL)
+		if (bufrel == NULL)
 		{
 			smgrblindwrt(DEFAULT_SMGR,
 						 bufHdr->tag.rnode,

src/backend/storage/lmgr/proc.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.143 2003/12/25 03:52:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/lmgr/proc.c,v 1.144 2004/01/07 18:56:27 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -745,7 +745,7 @@ ProcWakeup(PGPROC *proc, int errType)
 	/* Proc should be sleeping ... */
 	if (proc->links.prev == INVALID_OFFSET ||
 		proc->links.next == INVALID_OFFSET)
-		return (PGPROC *) NULL;
+		return NULL;
 
 	/* Save next process before we zap the list link */
 	retProc = (PGPROC *) MAKE_PTR(proc->links.next);

src/backend/storage/smgr/md.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/smgr/md.c,v 1.100 2004/01/06 18:07:31 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/smgr/md.c,v 1.101 2004/01/07 18:56:27 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -60,7 +60,7 @@ typedef struct _MdfdVec
 } MdfdVec;
 
 static int	Nfds = 100;			/* initial/current size of Md_fdvec array */
-static MdfdVec *Md_fdvec = (MdfdVec *) NULL;
+static MdfdVec *Md_fdvec = NULL;
 static int	Md_Free = -1;		/* head of freelist of unused fdvec
 								 * entries */
 static int	CurFd = 0;			/* first never-used fdvec index */
@@ -158,7 +158,7 @@ mdcreate(Relation reln)
 	Md_fdvec[vfd].mdfd_vfd = fd;
 	Md_fdvec[vfd].mdfd_flags = (uint16) 0;
 #ifndef LET_OS_MANAGE_FILESIZE
-	Md_fdvec[vfd].mdfd_chain = (MdfdVec *) NULL;
+	Md_fdvec[vfd].mdfd_chain = NULL;
 #endif
 
 	return vfd;
@@ -322,7 +322,7 @@ mdopen(Relation reln)
 	Md_fdvec[vfd].mdfd_vfd = fd;
 	Md_fdvec[vfd].mdfd_flags = (uint16) 0;
 #ifndef LET_OS_MANAGE_FILESIZE
-	Md_fdvec[vfd].mdfd_chain = (MdfdVec *) NULL;
+	Md_fdvec[vfd].mdfd_chain = NULL;
 	Assert(_mdnblocks(fd, BLCKSZ) <= ((BlockNumber) RELSEG_SIZE));
 #endif
 
@@ -359,7 +359,7 @@ mdclose_fd(int fd)
 	MdfdVec    *v;
 
 #ifndef LET_OS_MANAGE_FILESIZE
-	for (v = &Md_fdvec[fd]; v != (MdfdVec *) NULL;)
+	for (v = &Md_fdvec[fd]; v != NULL;)
 	{
 		MdfdVec    *ov = v;
 
@@ -372,10 +372,10 @@ mdclose_fd(int fd)
 			pfree(ov);
 	}
 
-	Md_fdvec[fd].mdfd_chain = (MdfdVec *) NULL;
+	Md_fdvec[fd].mdfd_chain = NULL;
 #else
 	v = &Md_fdvec[fd];
-	if (v != (MdfdVec *) NULL)
+	if (v != NULL)
 	{
 		if (v->mdfd_vfd >= 0)
 			FileClose(v->mdfd_vfd);
@@ -553,7 +553,7 @@ mdnblocks(Relation reln)
 	 * levels to handle that scenario by closing and re-opening the md
 	 * fd.)
 	 */
-	while (v->mdfd_chain != (MdfdVec *) NULL)
+	while (v->mdfd_chain != NULL)
 	{
 		segno++;
 		v = v->mdfd_chain;
@@ -572,7 +572,7 @@ mdnblocks(Relation reln)
 		 */
 		segno++;
 
-		if (v->mdfd_chain == (MdfdVec *) NULL)
+		if (v->mdfd_chain == NULL)
 		{
 			/*
 			 * Because we pass O_CREAT, we will create the next segment
@@ -582,7 +582,7 @@ mdnblocks(Relation reln)
 			 * worth.
 			 */
 			v->mdfd_chain = _mdfd_openseg(reln, segno, O_CREAT);
-			if (v->mdfd_chain == (MdfdVec *) NULL)
+			if (v->mdfd_chain == NULL)
 				elog(ERROR, "could not count blocks of \"%s\": %m",
 					 RelationGetRelationName(reln));
 		}
@@ -625,7 +625,7 @@ mdtruncate(Relation reln, BlockNumber nblocks)
 
 #ifndef LET_OS_MANAGE_FILESIZE
 	priorblocks = 0;
-	while (v != (MdfdVec *) NULL)
+	while (v != NULL)
 	{
 		MdfdVec    *ov = v;
 
@@ -660,7 +660,7 @@ mdtruncate(Relation reln, BlockNumber nblocks)
 			if (FileTruncate(v->mdfd_vfd, lastsegblocks * BLCKSZ) < 0)
 				return InvalidBlockNumber;
 			v = v->mdfd_chain;
-			ov->mdfd_chain = (MdfdVec *) NULL;
+			ov->mdfd_chain = NULL;
 		}
 		else
 		{
@@ -815,7 +815,7 @@ _mdfd_openseg(Relation reln, BlockNumber segno, int oflags)
 	pfree(fullpath);
 
 	if (fd < 0)
-		return (MdfdVec *) NULL;
+		return NULL;
 
 	/* allocate an mdfdvec entry for it */
 	v = (MdfdVec *) MemoryContextAlloc(MdCxt, sizeof(MdfdVec));
@@ -824,7 +824,7 @@ _mdfd_openseg(Relation reln, BlockNumber segno, int oflags)
 	v->mdfd_vfd = fd;
 	v->mdfd_flags = (uint16) 0;
 #ifndef LET_OS_MANAGE_FILESIZE
-	v->mdfd_chain = (MdfdVec *) NULL;
+	v->mdfd_chain = NULL;
 	Assert(_mdnblocks(fd, BLCKSZ) <= ((BlockNumber) RELSEG_SIZE));
 #endif
 
@@ -877,7 +877,7 @@ _mdfd_getseg(Relation reln, BlockNumber blkno)
 		 i++, segno--)
 	{
 
-		if (v->mdfd_chain == (MdfdVec *) NULL)
+		if (v->mdfd_chain == NULL)
 		{
 			/*
 			 * We will create the next segment only if the target block is
@@ -891,7 +891,7 @@ _mdfd_getseg(Relation reln, BlockNumber blkno)
 			 */
 			v->mdfd_chain = _mdfd_openseg(reln, i, (segno == 1) ? O_CREAT : 0);
 
-			if (v->mdfd_chain == (MdfdVec *) NULL)
+			if (v->mdfd_chain == NULL)
 				elog(ERROR, "could not open segment %u of relation \"%s\" (target block %u): %m",
 					 i, RelationGetRelationName(reln), blkno);
 		}

src/backend/storage/smgr/mm.c

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/smgr/mm.c,v 1.35 2003/11/29 19:51:57 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/smgr/mm.c,v 1.36 2004/01/07 18:56:27 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -96,7 +96,7 @@ mminit(void)
 	mmsize += MAXALIGN((MMNBUFFERS * sizeof(MMCacheTag)));
 	mmcacheblk = (char *) ShmemInitStruct("Main memory smgr", mmsize, &found);
 
-	if (mmcacheblk == (char *) NULL)
+	if (mmcacheblk == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		return SM_FAIL;
@@ -110,7 +110,7 @@ mminit(void)
 							  MMNBUFFERS, MMNBUFFERS,
 							  &info, (HASH_ELEM | HASH_FUNCTION));
 
-	if (MMCacheHT == (HTAB *) NULL)
+	if (MMCacheHT == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		return SM_FAIL;
@@ -124,7 +124,7 @@ mminit(void)
 								 MMNRELATIONS, MMNRELATIONS,
 								 &info, (HASH_ELEM | HASH_FUNCTION));
 
-	if (MMRelCacheHT == (HTAB *) NULL)
+	if (MMRelCacheHT == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		return SM_FAIL;
@@ -183,7 +183,7 @@ mmcreate(Relation reln)
 										   (void *) &tag,
 										   HASH_ENTER, &found);
 
-	if (entry == (MMRelHashEntry *) NULL)
+	if (entry == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		ereport(FATAL,
@@ -228,7 +228,7 @@ mmunlink(RelFileNode rnode)
 			entry = (MMHashEntry *) hash_search(MMCacheHT,
 												(void *) &MMBlockTags[i],
 												HASH_REMOVE, NULL);
-			if (entry == (MMHashEntry *) NULL)
+			if (entry == NULL)
 			{
 				LWLockRelease(MMCacheLock);
 				elog(FATAL, "cache hash table corrupted");
@@ -245,7 +245,7 @@ mmunlink(RelFileNode rnode)
 											(void *) &rtag,
 											HASH_REMOVE, NULL);
 
-	if (rentry == (MMRelHashEntry *) NULL)
+	if (rentry == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		elog(FATAL, "rel cache hash table corrupted");
@@ -308,7 +308,7 @@ mmextend(Relation reln, BlockNumber blocknum, char *buffer)
 	rentry = (MMRelHashEntry *) hash_search(MMRelCacheHT,
 											(void *) &rtag,
 											HASH_FIND, NULL);
-	if (rentry == (MMRelHashEntry *) NULL)
+	if (rentry == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		elog(FATAL, "rel cache hash table corrupted");
@@ -319,7 +319,7 @@ mmextend(Relation reln, BlockNumber blocknum, char *buffer)
 	entry = (MMHashEntry *) hash_search(MMCacheHT,
 										(void *) &tag,
 										HASH_ENTER, &found);
-	if (entry == (MMHashEntry *) NULL || found)
+	if (entry == NULL || found)
 	{
 		LWLockRelease(MMCacheLock);
 		elog(FATAL, "cache hash table corrupted");
@@ -389,7 +389,7 @@ mmread(Relation reln, BlockNumber blocknum, char *buffer)
 										(void *) &tag,
 										HASH_FIND, NULL);
 
-	if (entry == (MMHashEntry *) NULL)
+	if (entry == NULL)
 	{
 		/* reading nonexistent pages is defined to fill them with zeroes */
 		LWLockRelease(MMCacheLock);
@@ -430,7 +430,7 @@ mmwrite(Relation reln, BlockNumber blocknum, char *buffer)
 										(void *) &tag,
 										HASH_FIND, NULL);
 
-	if (entry == (MMHashEntry *) NULL)
+	if (entry == NULL)
 	{
 		LWLockRelease(MMCacheLock);
 		elog(FATAL, "cache hash table missing requested page");