Windows specific vsnprintf fixes.

* Changes flac_snprintf (in src/share/grabbag/snprintf.c) and its copy
  local_snprintf (src/libFLAC/metadata_iterators.c) to be almost sane.

* Adds flac_vsnprintf (src/share/grabbag/snprintf.c) and its copy
  local_vsnprintf (src/share/win_utf8_io/win_utf8_io.c).

* Changes stats_print_info in src/flac/utils.c so it uses flac_vsnprintf
  instead of vsnprintf. This makes return value checking unnecessary.

Patch-from: lvqcl <lvqcl.mail@gmail.com>

1 files changed, 29 insertions, 4 deletions

diff --git a/src/share/grabbag/snprintf.c b/src/share/grabbag/snprintf.c
index 3a0661f0..d19e42c1 100644
--- a/src/share/grabbag/snprintf.c
+++ b/src/share/grabbag/snprintf.c
@@ -49,7 +49,7 @@
  * does not over-write the end of the buffer. MS's snprintf_s in this case
  * returns -1.
  *
- * The _MSC_VER code below attempts to modify the return code for snprintf_s
+ * The _MSC_VER code below attempts to modify the return code for vsnprintf_s
  * to something that is more compatible with the behaviour of the ISO C version.
  */
 
@@ -57,13 +57,18 @@ int
 flac_snprintf(char *str, size_t size, const char *fmt, ...)
 {
 	va_list va;
-	int rc ;
+	int rc;
 
 	va_start (va, fmt);
 
-#ifdef _MSC_VER
+#if defined _MSC_VER
+	if (size == 0)
+		return 1024;
 	rc = vsnprintf_s (str, size, _TRUNCATE, fmt, va);
-	rc = (rc > 0) ? rc : (size == 0 ? 1024 : size * 2);
+	if (rc < 0)
+		rc = size - 1;
+#elif defined __MINGW32__
+	rc = __mingw_vsnprintf (str, size, fmt, va);
 #else
 	rc = vsnprintf (str, size, fmt, va);
 #endif
@@ -71,3 +76,23 @@ flac_snprintf(char *str, size_t size, const char *fmt, ...)
 
 	return rc;
 }
+
+int
+flac_vsnprintf(char *str, size_t size, const char *fmt, va_list va)
+{
+	int rc;
+
+#if defined _MSC_VER
+	if (size == 0)
+		return 1024;
+	rc = vsnprintf_s (str, size, _TRUNCATE, fmt, va);
+	if (rc < 0)
+		rc = size - 1;
+#elif defined __MINGW32__
+	rc = __mingw_vsnprintf (str, size, fmt, va);
+#else
+	rc = vsnprintf (str, size, fmt, va);
+#endif
+
+	return rc;
+}