Change argument of appendBinaryStringInfo from char * to void *

petere · petere · commit 1f605b82ba66 · 2022-12-30T11:05:09.000+01:00
There is some code that uses this function to assemble some kind of packed binary layout, which requires a bunch of casts because of this. Functions taking binary data plus length should take void * instead, like memcpy() for example. Discussion: https://www.postgresql.org/message-id/flat/a0086cfc-ff0f-2827-20fe-52b591d2666c%40enterprisedb.com
diff --git a/src/backend/utils/adt/jsonpath.c b/src/backend/utils/adt/jsonpath.c
@@ -267,18 +267,18 @@ flattenJsonPathParseItem(StringInfo buf,  int *result, struct Node *escontext,
 		case jpiString:
 		case jpiVariable:
 		case jpiKey:
-			appendBinaryStringInfo(buf, (char *) &item->value.string.len,
+			appendBinaryStringInfo(buf, &item->value.string.len,
 								   sizeof(item->value.string.len));
 			appendBinaryStringInfo(buf, item->value.string.val,
 								   item->value.string.len);
 			appendStringInfoChar(buf, '\0');
 			break;
 		case jpiNumeric:
-			appendBinaryStringInfo(buf, (char *) item->value.numeric,
+			appendBinaryStringInfo(buf, item->value.numeric,
 								   VARSIZE(item->value.numeric));
 			break;
 		case jpiBool:
-			appendBinaryStringInfo(buf, (char *) &item->value.boolean,
+			appendBinaryStringInfo(buf, &item->value.boolean,
 								   sizeof(item->value.boolean));
 			break;
 		case jpiAnd:
@@ -328,11 +328,11 @@ flattenJsonPathParseItem(StringInfo buf,  int *result, struct Node *escontext,
 				int32		offs;
 
 				appendBinaryStringInfo(buf,
-									   (char *) &item->value.like_regex.flags,
+									   &item->value.like_regex.flags,
 									   sizeof(item->value.like_regex.flags));
 				offs = reserveSpaceForItemPointer(buf);
 				appendBinaryStringInfo(buf,
-									   (char *) &item->value.like_regex.patternlen,
+									   &item->value.like_regex.patternlen,
 									   sizeof(item->value.like_regex.patternlen));
 				appendBinaryStringInfo(buf, item->value.like_regex.pattern,
 									   item->value.like_regex.patternlen);
@@ -393,7 +393,7 @@ flattenJsonPathParseItem(StringInfo buf,  int *result, struct Node *escontext,
 				int			offset;
 				int			i;
 
-				appendBinaryStringInfo(buf, (char *) &nelems, sizeof(nelems));
+				appendBinaryStringInfo(buf, &nelems, sizeof(nelems));
 
 				offset = buf->len;
 
@@ -431,10 +431,10 @@ flattenJsonPathParseItem(StringInfo buf,  int *result, struct Node *escontext,
 			break;
 		case jpiAny:
 			appendBinaryStringInfo(buf,
-								   (char *) &item->value.anybounds.first,
+								   &item->value.anybounds.first,
 								   sizeof(item->value.anybounds.first));
 			appendBinaryStringInfo(buf,
-								   (char *) &item->value.anybounds.last,
+								   &item->value.anybounds.last,
 								   sizeof(item->value.anybounds.last));
 			break;
 		case jpiType:
@@ -496,7 +496,7 @@ reserveSpaceForItemPointer(StringInfo buf)
 	int32		pos = buf->len;
 	int32		ptr = 0;
 
-	appendBinaryStringInfo(buf, (char *) &ptr, sizeof(ptr));
+	appendBinaryStringInfo(buf, &ptr, sizeof(ptr));
 
 	return pos;
 }
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
@@ -260,7 +260,7 @@ buf_init(FullTransactionId xmin, FullTransactionId xmax)
 	snap.nxip = 0;
 
 	buf = makeStringInfo();
-	appendBinaryStringInfo(buf, (char *) &snap, PG_SNAPSHOT_SIZE(0));
+	appendBinaryStringInfo(buf, &snap, PG_SNAPSHOT_SIZE(0));
 	return buf;
 }
 
@@ -272,7 +272,7 @@ buf_add_txid(StringInfo buf, FullTransactionId fxid)
 	/* do this before possible realloc */
 	snap->nxip++;
 
-	appendBinaryStringInfo(buf, (char *) &fxid, sizeof(fxid));
+	appendBinaryStringInfo(buf, &fxid, sizeof(fxid));
 }
 
 static pg_snapshot *
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
@@ -224,7 +224,7 @@ appendStringInfoSpaces(StringInfo str, int count)
  * if necessary. Ensures that a trailing null byte is present.
  */
 void
-appendBinaryStringInfo(StringInfo str, const char *data, int datalen)
+appendBinaryStringInfo(StringInfo str, const void *data, int datalen)
 {
 	Assert(str != NULL);
 
@@ -250,7 +250,7 @@ appendBinaryStringInfo(StringInfo str, const char *data, int datalen)
  * if necessary. Does not ensure a trailing null-byte exists.
  */
 void
-appendBinaryStringInfoNT(StringInfo str, const char *data, int datalen)
+appendBinaryStringInfoNT(StringInfo str, const void *data, int datalen)
 {
 	Assert(str != NULL);
 
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
@@ -142,15 +142,15 @@ extern void appendStringInfoSpaces(StringInfo str, int count);
  * if necessary.
  */
 extern void appendBinaryStringInfo(StringInfo str,
-								   const char *data, int datalen);
+								   const void *data, int datalen);
 
 /*------------------------
  * appendBinaryStringInfoNT
  * Append arbitrary binary data to a StringInfo, allocating more space
  * if necessary. Does not ensure a trailing null-byte exists.
  */
 extern void appendBinaryStringInfoNT(StringInfo str,
-									 const char *data, int datalen);
+									 const void *data, int datalen);
 
 /*------------------------
  * enlargeStringInfo

Original file line number	Diff line number	Diff line change
`@@ -260,7 +260,7 @@ buf_init(FullTransactionId xmin, FullTransactionId xmax)`
`260`	`260`	`snap.nxip = 0;`
`261`	`261`
`262`	`262`	`buf = makeStringInfo();`
`263`		`- appendBinaryStringInfo(buf, (char *) &snap, PG_SNAPSHOT_SIZE(0));`
	`263`	`+ appendBinaryStringInfo(buf, &snap, PG_SNAPSHOT_SIZE(0));`
`264`	`264`	`return buf;`
`265`	`265`	`}`
`266`	`266`
`@@ -272,7 +272,7 @@ buf_add_txid(StringInfo buf, FullTransactionId fxid)`
`272`	`272`	`/* do this before possible realloc */`
`273`	`273`	`snap->nxip++;`
`274`	`274`
`275`		`- appendBinaryStringInfo(buf, (char *) &fxid, sizeof(fxid));`
	`275`	`+ appendBinaryStringInfo(buf, &fxid, sizeof(fxid));`
`276`	`276`	`}`
`277`	`277`
`278`	`278`	`static pg_snapshot *`