rev-parse: make "whatchanged -- git-fetch-script" work again.

diff --git a/index-pack.c b/index-pack.c
index 785fe71a6fb5e518f92d62bace43cdd13f3c37ae..541d7bc1c1723c1a41cd35349b607223c94a4dca 100644 (file)
--- a/index-pack.c
+++ b/index-pack.c
@@ -352,18 +352,24 @@ static int sha1_compare(const void *_a, const void *_b)
 static void write_index_file(const char *index_name, unsigned char *sha1)
 {
        struct sha1file *f;
-       struct object_entry **sorted_by_sha =
-               xcalloc(nr_objects, sizeof(struct object_entry *));
-       struct object_entry **list = sorted_by_sha;
-       struct object_entry **last = sorted_by_sha + nr_objects;
+       struct object_entry **sorted_by_sha, **list, **last;
        unsigned int array[256];
        int i;
        SHA_CTX ctx;
 
-       for (i = 0; i < nr_objects; ++i)
-               sorted_by_sha[i] = &objects[i];
-       qsort(sorted_by_sha, nr_objects, sizeof(sorted_by_sha[0]),
-             sha1_compare);
+       if (nr_objects) {
+               sorted_by_sha =
+                       xcalloc(nr_objects, sizeof(struct object_entry *));
+               list = sorted_by_sha;
+               last = sorted_by_sha + nr_objects;
+               for (i = 0; i < nr_objects; ++i)
+                       sorted_by_sha[i] = &objects[i];
+               qsort(sorted_by_sha, nr_objects, sizeof(sorted_by_sha[0]),
+                     sha1_compare);
+
+       }
+       else
+               sorted_by_sha = list = last = NULL;
 
        unlink(index_name);
        f = sha1create("%s", index_name);
@@ -440,7 +446,7 @@ int main(int argc, char **argv)
                if (len < 5 || strcmp(pack_name + len - 5, ".pack"))
                        die("packfile name '%s' does not end with '.pack'",
                            pack_name);
-               index_name_buf = xmalloc(len - 1);
+               index_name_buf = xmalloc(len);
                memcpy(index_name_buf, pack_name, len - 5);
                strcpy(index_name_buf + len - 5, ".idx");
                index_name = index_name_buf;