backend libpq void * argument for binary data

Change some backend libpq functions to take void * for binary data
instead of char *.  This removes the need for numerous casts.

Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org

src/backend/libpq/pqcomm.c

@@ -144,7 +144,7 @@ static int	socket_flush_if_writable(void);
 static bool socket_is_send_pending(void);
 static int	socket_putmessage(char msgtype, const char *s, size_t len);
 static void socket_putmessage_noblock(char msgtype, const char *s, size_t len);
-static inline int internal_putbytes(const char *s, size_t len);
+static inline int internal_putbytes(const void *b, size_t len);
 static inline int internal_flush(void);
 static pg_noinline int internal_flush_buffer(const char *buf, size_t *start,
 											 size_t *end);
@@ -1060,8 +1060,9 @@ pq_getbyte_if_available(unsigned char *c)
  * --------------------------------
  */
 int
-pq_getbytes(char *s, size_t len)
+pq_getbytes(void *b, size_t len)
 {
+	char	   *s = b;
 	size_t		amount;
 
 	Assert(PqCommReadingMsg);
@@ -1209,7 +1210,7 @@ pq_getmessage(StringInfo s, int maxlen)
 	resetStringInfo(s);
 
 	/* Read message length word */
-	if (pq_getbytes((char *) &len, 4) == EOF)
+	if (pq_getbytes(&len, 4) == EOF)
 	{
 		ereport(COMMERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
@@ -1274,8 +1275,10 @@ pq_getmessage(StringInfo s, int maxlen)
 
 
 static inline int
-internal_putbytes(const char *s, size_t len)
+internal_putbytes(const void *b, size_t len)
 {
+	const char *s = b;
+
 	while (len > 0)
 	{
 		/* If buffer is full, then flush it out */
@@ -1499,7 +1502,7 @@ socket_putmessage(char msgtype, const char *s, size_t len)
 		goto fail;
 
 	n32 = pg_hton32((uint32) (len + 4));
-	if (internal_putbytes((char *) &n32, 4))
+	if (internal_putbytes(&n32, 4))
 		goto fail;
 
 	if (internal_putbytes(s, len))

src/backend/libpq/pqformat.c

@@ -422,15 +422,15 @@ pq_getmsgint(StringInfo msg, int b)
 	switch (b)
 	{
 		case 1:
-			pq_copymsgbytes(msg, (char *) &n8, 1);
+			pq_copymsgbytes(msg, &n8, 1);
 			result = n8;
 			break;
 		case 2:
-			pq_copymsgbytes(msg, (char *) &n16, 2);
+			pq_copymsgbytes(msg, &n16, 2);
 			result = pg_ntoh16(n16);
 			break;
 		case 4:
-			pq_copymsgbytes(msg, (char *) &n32, 4);
+			pq_copymsgbytes(msg, &n32, 4);
 			result = pg_ntoh32(n32);
 			break;
 		default:
@@ -454,7 +454,7 @@ pq_getmsgint64(StringInfo msg)
 {
 	uint64		n64;
 
-	pq_copymsgbytes(msg, (char *) &n64, sizeof(n64));
+	pq_copymsgbytes(msg, &n64, sizeof(n64));
 
 	return pg_ntoh64(n64);
 }
@@ -525,7 +525,7 @@ pq_getmsgbytes(StringInfo msg, int datalen)
  * --------------------------------
  */
 void
-pq_copymsgbytes(StringInfo msg, char *buf, int datalen)
+pq_copymsgbytes(StringInfo msg, void *buf, int datalen)
 {
 	if (datalen < 0 || datalen > (msg->len - msg->cursor))
 		ereport(ERROR,

src/backend/tcop/backend_startup.c

@@ -480,7 +480,7 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 	 * sound inefficient, but it's not really, because of buffering in
 	 * pqcomm.c.)
 	 */
-	if (pq_getbytes((char *) &len, 1) == EOF)
+	if (pq_getbytes(&len, 1) == EOF)
 	{
 		/*
 		 * If we get no data at all, don't clutter the log with a complaint;

src/backend/utils/adt/varbit.c

@@ -361,7 +361,7 @@ bit_recv(PG_FUNCTION_ARGS)
 	SET_VARSIZE(result, len);
 	VARBITLEN(result) = bitlen;
 
-	pq_copymsgbytes(buf, (char *) VARBITS(result), VARBITBYTES(result));
+	pq_copymsgbytes(buf, VARBITS(result), VARBITBYTES(result));
 
 	/* Make sure last byte is correctly zero-padded */
 	VARBIT_PAD(result);
@@ -666,7 +666,7 @@ varbit_recv(PG_FUNCTION_ARGS)
 	SET_VARSIZE(result, len);
 	VARBITLEN(result) = bitlen;
 
-	pq_copymsgbytes(buf, (char *) VARBITS(result), VARBITBYTES(result));
+	pq_copymsgbytes(buf, VARBITS(result), VARBITBYTES(result));
 
 	/* Make sure last byte is correctly zero-padded */
 	VARBIT_PAD(result);

src/include/libpq/libpq.h

@@ -71,7 +71,7 @@ extern int	AcceptConnection(pgsocket server_fd, ClientSocket *client_sock);
 extern void TouchSocketFiles(void);
 extern void RemoveSocketFiles(void);
 extern Port *pq_init(ClientSocket *client_sock);
-extern int	pq_getbytes(char *s, size_t len);
+extern int	pq_getbytes(void *b, size_t len);
 extern void pq_startmsgread(void);
 extern void pq_endmsgread(void);
 extern bool pq_is_reading_msg(void);

src/include/libpq/pqformat.h

@@ -200,7 +200,7 @@ extern int64 pq_getmsgint64(StringInfo msg);
 extern float4 pq_getmsgfloat4(StringInfo msg);
 extern float8 pq_getmsgfloat8(StringInfo msg);
 extern const char *pq_getmsgbytes(StringInfo msg, int datalen);
-extern void pq_copymsgbytes(StringInfo msg, char *buf, int datalen);
+extern void pq_copymsgbytes(StringInfo msg, void *buf, int datalen);
 extern char *pq_getmsgtext(StringInfo msg, int rawbytes, int *nbytes);
 extern const char *pq_getmsgstring(StringInfo msg);
 extern const char *pq_getmsgrawstring(StringInfo msg);