r25209: unify logic of talloc_vasprintf_append() and talloc_vasprintf_append_buffer()

metze
(This used to be commit 780c1c776e15f7224256a0ba0bda3e9f04702abe)

1 files changed, 29 insertions, 50 deletions

diff --git a/source4/lib/talloc/talloc.c b/source4/lib/talloc/talloc.c
index 0b4d977aa7..033e70d2f9 100644
--- a/source4/lib/talloc/talloc.c
+++ b/source4/lib/talloc/talloc.c
@@ -1313,30 +1313,18 @@ char *talloc_asprintf(const void *t, const char *fmt, ...)
 	return ret;
 }
 
-
-/**
- * Realloc @p s to append the formatted result of @p fmt and @p ap,
- * and return @p s, which may have moved.  Good for gradually
- * accumulating output into a string buffer. Appends at the end
- * of the string.
- **/
-char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
+static inline char *__talloc_vaslenprintf_append(char *s, size_t slen,
+						 const char *fmt, va_list ap)
 {
-	int len, s_len;
+	ssize_t alen;
 	va_list ap2;
 	char c;
 
-	if (s == NULL) {
-		return talloc_vasprintf(NULL, fmt, ap);
-	}
-
-	s_len = strlen(s);
-
 	va_copy(ap2, ap);
-	len = vsnprintf(&c, 1, fmt, ap2);
+	alen = vsnprintf(&c, 1, fmt, ap2);
 	va_end(ap2);
 
-	if (len <= 0) {
+	if (alen <= 0) {
 		/* Either the vsnprintf failed or the format resulted in
 		 * no characters being formatted. In the former case, we
 		 * ought to return NULL, in the latter we ought to return
@@ -1346,60 +1334,51 @@ char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
 		return s;
 	}
 
-	s = talloc_realloc(NULL, s, char, s_len + len+1);
+	s = talloc_realloc(NULL, s, char, slen + alen + 1);
 	if (!s) return NULL;
 
 	va_copy(ap2, ap);
-	vsnprintf(s+s_len, len+1, fmt, ap2);
+	vsnprintf(s + slen, alen + 1, fmt, ap2);
 	va_end(ap2);
-	_talloc_set_name_const(s, s);
 
+	_talloc_set_name_const(s, s);
 	return s;
 }
 
 /**
  * Realloc @p s to append the formatted result of @p fmt and @p ap,
+ * and return @p s, which may have moved.  Good for gradually
+ * accumulating output into a string buffer. Appends at the end
+ * of the string.
+ **/
+char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
+{
+	if (unlikely(!s)) {
+		return talloc_vasprintf(NULL, fmt, ap);
+	}
+
+	return __talloc_vaslenprintf_append(s, strlen(s), fmt, ap);
+}
+
+/**
+ * Realloc @p s to append the formatted result of @p fmt and @p ap,
  * and return @p s, which may have moved. Always appends at the
  * end of the talloc'ed buffer, not the end of the string.
  **/
 char *talloc_vasprintf_append_buffer(char *s, const char *fmt, va_list ap)
 {
-	struct talloc_chunk *tc;
-	int len, s_len;
-	va_list ap2;
-	char c;
+	size_t slen;
 
-	if (s == NULL) {
+	if (unlikely(!s)) {
 		return talloc_vasprintf(NULL, fmt, ap);
 	}
 
-	tc = talloc_chunk_from_ptr(s);
-
-	s_len = tc->size - 1;
-
-	va_copy(ap2, ap);
-	len = vsnprintf(&c, 1, fmt, ap2);
-	va_end(ap2);
-
-	if (len <= 0) {
-		/* Either the vsnprintf failed or the format resulted in
-		 * no characters being formatted. In the former case, we
-		 * ought to return NULL, in the latter we ought to return
-		 * the original string. Most current callers of this
-		 * function expect it to never return NULL.
-		 */
-		return s;
+	slen = talloc_get_size(s);
+	if (likely(slen > 0)) {
+		slen--;
 	}
 
-	s = talloc_realloc(NULL, s, char, s_len + len+1);
-	if (!s) return NULL;
-
-	va_copy(ap2, ap);
-	vsnprintf(s+s_len, len+1, fmt, ap2);
-	va_end(ap2);
-	_talloc_set_name_const(s, s);
-
-	return s;
+	return __talloc_vaslenprintf_append(s, slen, fmt, ap);
 }
 
 /*