do not write null sha1s to on-disk index

diff --git a/patch-delta.c b/patch-delta.c
index ef748ce96d246bb17c6e64b51b882d535d7f7774..56e0a5ede22c9396fc897bf1d3444dce92d8916f 100644 (file)
--- a/patch-delta.c
+++ b/patch-delta.c
@@ -2,7 +2,7 @@
  * patch-delta.c:
  * recreate a buffer from a source and the delta produced by diff-delta.c
  *
- * (C) 2005 Nicolas Pitre <nico@cam.org>
+ * (C) 2005 Nicolas Pitre <nico@fluxnic.net>
  *
  * This code is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -33,8 +33,7 @@ void *patch_delta(const void *src_buf, unsigned long src_size,
 
        /* now the result size */
        size = get_delta_hdr_size(&data, top);
-       dst_buf = xmalloc(size + 1);
-       dst_buf[size] = 0;
+       dst_buf = xmallocz(size);
 
        out = dst_buf;
        while (data < top) {
@@ -49,7 +48,7 @@ void *patch_delta(const void *src_buf, unsigned long src_size,
                        if (cmd & 0x20) cp_size |= (*data++ << 8);
                        if (cmd & 0x40) cp_size |= (*data++ << 16);
                        if (cp_size == 0) cp_size = 0x10000;
-                       if (cp_off + cp_size < cp_size ||
+                       if (unsigned_add_overflows(cp_off, cp_size) ||
                            cp_off + cp_size > src_size ||
                            cp_size > size)
                                break;