# HG changeset patch
# User Bruno Haible <bruno@clisp.org>
# Date 1097165722 0
# Node ID f038f3333cc8d0b4f31d6f2f6ec8e6922e6dadaa
# Parent  e28d7c1dc1d39019bb7821b7a9e35d8fea1da49b
Avoid a memory allocation when possible.

diff --git a/lib/ChangeLog b/lib/ChangeLog
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,8 @@
+2004-10-07  Bruno Haible  <bruno@clisp.org>
+
+	* snprintf.c (snprintf): Avoid a memory allocation if the result fits
+	into the provided buffer.
+
 2004-10-06  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* diacrit.c, diacrit.h: Add GPL notice.
diff --git a/lib/snprintf.c b/lib/snprintf.c
--- a/lib/snprintf.c
+++ b/lib/snprintf.c
@@ -42,19 +42,19 @@
   va_list args;
 
   va_start (args, format);
-  output = vasnprintf (NULL, &len, format, args);
+  len = size;
+  output = vasnprintf (str, &len, format, args);
   va_end (args);
 
   if (!output)
     return -1;
 
-  if (str && size > 0)
-    {
-      memcpy (str, output, MIN (len + 1, size));
+  if (str != NULL)
+    if (len > size - 1) /* equivalent to: (size > 0 && len >= size) */
       str[size - 1] = '\0';
-    }
 
-  free (output);
+  if (output != str)
+    free (output);
 
   return len;
 }