[Peter Eisentraut <peter.eisentraut@enterprisedb.com>]

Here are a couple of patches that clean up the internal File API and 
related things a bit:

0001-Update-types-in-File-API.patch

     Make the argument types of the File API match stdio better:

     - Change the data buffer to void *, from char *.
     - Change FileWrite() data buffer to const on top of that.
     - Change amounts to size_t, from int.

     In passing, change the FilePrefetch() amount argument from int to
     off_t, to match the underlying posix_fadvise().

0002-Remove-unnecessary-casts.patch

     Some code carefully cast all data buffer arguments for
     BufFileWrite() and BufFileRead() to void *, even though the
     arguments are already void * (and AFAICT were never anything else).
     Remove this unnecessary clutter.

(I had initially thought these casts were related to the first patch, 
but as I said the BufFile API never used char * arguments, so this 
turned out to be unrelated, but still weird.)

Attachments: download all (2 files, .tar.gz)

0001-Update-types-in-File-API.patch (text/plain, 3.2K) download
From 0ca35b75e383272356ba49211913d8aead5ca10d Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Thu, 1 Dec 2022 08:36:09 +0100
Subject: [PATCH 1/2] Update types in File API

Make the argument types of the File API match stdio better:

- Change the data buffer to void *, from char *.
- Change FileWrite() data buffer to const on top of that.
- Change amounts to size_t, from int.

In passing, change the FilePrefetch() amount argument from int to
off_t, to match the underlying posix_fadvise().
---
 src/backend/storage/file/fd.c | 8 ++++----
 src/include/storage/fd.h      | 6 +++---
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 4151cafec547..f6c938202309 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -1980,7 +1980,7 @@ FileClose(File file)
  * to read into.
  */
 int
-FilePrefetch(File file, off_t offset, int amount, uint32 wait_event_info)
+FilePrefetch(File file, off_t offset, off_t amount, uint32 wait_event_info)
 {
 #if defined(USE_POSIX_FADVISE) && defined(POSIX_FADV_WILLNEED)
 	int			returnCode;
@@ -2031,7 +2031,7 @@ FileWriteback(File file, off_t offset, off_t nbytes, uint32 wait_event_info)
 }
 
 int
-FileRead(File file, char *buffer, int amount, off_t offset,
+FileRead(File file, void *buffer, size_t amount, off_t offset,
 		 uint32 wait_event_info)
 {
 	int			returnCode;
@@ -2039,7 +2039,7 @@ FileRead(File file, char *buffer, int amount, off_t offset,
 
 	Assert(FileIsValid(file));
 
-	DO_DB(elog(LOG, "FileRead: %d (%s) " INT64_FORMAT " %d %p",
+	DO_DB(elog(LOG, "FileRead: %d (%s) " INT64_FORMAT " %zu %p",
 			   file, VfdCache[file].fileName,
 			   (int64) offset,
 			   amount, buffer));
@@ -2087,7 +2087,7 @@ FileRead(File file, char *buffer, int amount, off_t offset,
 }
 
 int
-FileWrite(File file, char *buffer, int amount, off_t offset,
+FileWrite(File file, const void *buffer, size_t amount, off_t offset,
 		  uint32 wait_event_info)
 {
 	int			returnCode;
diff --git a/src/include/storage/fd.h b/src/include/storage/fd.h
index c0a212487d92..7144fc9f6050 100644
--- a/src/include/storage/fd.h
+++ b/src/include/storage/fd.h
@@ -102,9 +102,9 @@ extern File PathNameOpenFile(const char *fileName, int fileFlags);
 extern File PathNameOpenFilePerm(const char *fileName, int fileFlags, mode_t fileMode);
 extern File OpenTemporaryFile(bool interXact);
 extern void FileClose(File file);
-extern int	FilePrefetch(File file, off_t offset, int amount, uint32 wait_event_info);
-extern int	FileRead(File file, char *buffer, int amount, off_t offset, uint32 wait_event_info);
-extern int	FileWrite(File file, char *buffer, int amount, off_t offset, uint32 wait_event_info);
+extern int	FilePrefetch(File file, off_t offset, off_t amount, uint32 wait_event_info);
+extern int	FileRead(File file, void *buffer, size_t amount, off_t offset, uint32 wait_event_info);
+extern int	FileWrite(File file, const void *buffer, size_t amount, off_t offset, uint32 wait_event_info);
 extern int	FileSync(File file, uint32 wait_event_info);
 extern off_t FileSize(File file);
 extern int	FileTruncate(File file, off_t offset, uint32 wait_event_info);

base-commit: 43351557d0d2b9c5e20298b5fee2849abef86aff
-- 
2.38.1



0002-Remove-unnecessary-casts.patch (text/plain, 3.7K) download
From 8d0530fbf9095bc16fa3465b69aef2c31c4c3c9b Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Thu, 1 Dec 2022 08:36:09 +0100
Subject: [PATCH 2/2] Remove unnecessary casts

Some code carefully cast all data buffer arguments for BufFileWrite()
and BufFileRead() to void *, even though the arguments are already
void * (and AFAICT were never anything else).  Remove this unnecessary
clutter.
---
 src/backend/executor/nodeHashjoin.c |  8 ++++----
 src/backend/utils/sort/tuplestore.c | 12 ++++++------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/src/backend/executor/nodeHashjoin.c b/src/backend/executor/nodeHashjoin.c
index 2718c2113f58..3e1a997f920d 100644
--- a/src/backend/executor/nodeHashjoin.c
+++ b/src/backend/executor/nodeHashjoin.c
@@ -1227,8 +1227,8 @@ ExecHashJoinSaveTuple(MinimalTuple tuple, uint32 hashvalue,
 		*fileptr = file;
 	}
 
-	BufFileWrite(file, (void *) &hashvalue, sizeof(uint32));
-	BufFileWrite(file, (void *) tuple, tuple->t_len);
+	BufFileWrite(file, &hashvalue, sizeof(uint32));
+	BufFileWrite(file, tuple, tuple->t_len);
 }
 
 /*
@@ -1260,7 +1260,7 @@ ExecHashJoinGetSavedTuple(HashJoinState *hjstate,
 	 * we can read them both in one BufFileRead() call without any type
 	 * cheating.
 	 */
-	nread = BufFileRead(file, (void *) header, sizeof(header));
+	nread = BufFileRead(file, header, sizeof(header));
 	if (nread == 0)				/* end of file */
 	{
 		ExecClearTuple(tupleSlot);
@@ -1275,7 +1275,7 @@ ExecHashJoinGetSavedTuple(HashJoinState *hjstate,
 	tuple = (MinimalTuple) palloc(header[1]);
 	tuple->t_len = header[1];
 	nread = BufFileRead(file,
-						(void *) ((char *) tuple + sizeof(uint32)),
+						((char *) tuple + sizeof(uint32)),
 						header[1] - sizeof(uint32));
 	if (nread != header[1] - sizeof(uint32))
 		ereport(ERROR,
diff --git a/src/backend/utils/sort/tuplestore.c b/src/backend/utils/sort/tuplestore.c
index f605ece721eb..cc884ab11649 100644
--- a/src/backend/utils/sort/tuplestore.c
+++ b/src/backend/utils/sort/tuplestore.c
@@ -1468,7 +1468,7 @@ getlen(Tuplestorestate *state, bool eofOK)
 	unsigned int len;
 	size_t		nbytes;
 
-	nbytes = BufFileRead(state->myfile, (void *) &len, sizeof(len));
+	nbytes = BufFileRead(state->myfile, &len, sizeof(len));
 	if (nbytes == sizeof(len))
 		return len;
 	if (nbytes != 0 || !eofOK)
@@ -1512,10 +1512,10 @@ writetup_heap(Tuplestorestate *state, void *tup)
 	/* total on-disk footprint: */
 	unsigned int tuplen = tupbodylen + sizeof(int);
 
-	BufFileWrite(state->myfile, (void *) &tuplen, sizeof(tuplen));
-	BufFileWrite(state->myfile, (void *) tupbody, tupbodylen);
+	BufFileWrite(state->myfile, &tuplen, sizeof(tuplen));
+	BufFileWrite(state->myfile, tupbody, tupbodylen);
 	if (state->backward)		/* need trailing length word? */
-		BufFileWrite(state->myfile, (void *) &tuplen, sizeof(tuplen));
+		BufFileWrite(state->myfile, &tuplen, sizeof(tuplen));
 
 	FREEMEM(state, GetMemoryChunkSpace(tuple));
 	heap_free_minimal_tuple(tuple);
@@ -1533,7 +1533,7 @@ readtup_heap(Tuplestorestate *state, unsigned int len)
 	USEMEM(state, GetMemoryChunkSpace(tuple));
 	/* read in the tuple proper */
 	tuple->t_len = tuplen;
-	nread = BufFileRead(state->myfile, (void *) tupbody, tupbodylen);
+	nread = BufFileRead(state->myfile, tupbody, tupbodylen);
 	if (nread != (size_t) tupbodylen)
 		ereport(ERROR,
 				(errcode_for_file_access(),
@@ -1541,7 +1541,7 @@ readtup_heap(Tuplestorestate *state, unsigned int len)
 						nread, (size_t) tupbodylen)));
 	if (state->backward)		/* need trailing length word? */
 	{
-		nread = BufFileRead(state->myfile, (void *) &tuplen, sizeof(tuplen));
+		nread = BufFileRead(state->myfile, &tuplen, sizeof(tuplen));
 		if (nread != sizeof(tuplen))
 			ereport(ERROR,
 					(errcode_for_file_access(),
-- 
2.38.1