Fix a memory leak in realloc_buffer.

If realloc fails, the original block is left untouched. So
don't overwrite it that we can free it.


git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@411 7dcaeef0-15fb-0310-b436-a5af3365683c

libssh/buffer.c

@@ -68,16 +68,19 @@ void buffer_free(struct buffer_struct *buffer) {
 
 static int realloc_buffer(struct buffer_struct *buffer, int needed) {
   int smallest = 1;
+  char *new = NULL;
   /* Find the smallest power of two which is greater or equal to needed */
   while(smallest <= needed) {
     smallest <<= 1;
   }
   needed = smallest;
-  buffer->data = realloc(buffer->data, needed);
-  if (buffer->data == NULL) {
+  new = realloc(buffer->data, needed);
+  if (new == NULL) {
     return -1;
   }
+  buffer->data = new;
   buffer->allocated = needed;
+
   return 0;
 }