racy-git: an empty blob has a fixed object name

diff --git a/builtin-apply.c b/builtin-apply.c
index a3f075df4bd91de8d3423420cfcffd9722ad9586..30d26e57b30821d6b11efe4f493da6d35fb1dc18 100644 (file)
--- a/builtin-apply.c
+++ b/builtin-apply.c
@@ -1937,21 +1937,24 @@ static int apply_one_fragment(struct image *img, struct fragment *frag,
        trailing = frag->trailing;
 
        /*
-        * If we don't have any leading/trailing data in the patch,
-        * we want it to match at the beginning/end of the file.
+        * A hunk to change lines at the beginning would begin with
+        * @@ -1,L +N,M @@
         *
-        * But that would break if the patch is generated with
-        * --unified=0; sane people wouldn't do that to cause us
-        * trouble, but we try to please not so sane ones as well.
+        * And a hunk to add to an empty file would begin with
+        * @@ -0,0 +N,M @@
+        *
+        * In other words, a hunk that is (frag->oldpos <= 1) with or
+        * without leading context must match at the beginning.
         */
-       if (unidiff_zero) {
-               match_beginning = (!leading && !frag->oldpos);
-               match_end = 0;
-       }
-       else {
-               match_beginning = !leading && (frag->oldpos == 1);
-               match_end = !trailing;
-       }
+       match_beginning = frag->oldpos <= 1;
+
+       /*
+        * A hunk without trailing lines must match at the end.
+        * However, we simply cannot tell if a hunk must match end
+        * from the lack of trailing lines if the patch was generated
+        * with unidiff without any context.
+        */
+       match_end = !unidiff_zero && !trailing;
 
        pos = frag->newpos ? (frag->newpos - 1) : 0;
        preimage.buf = oldlines;
@@ -2994,7 +2997,7 @@ int cmd_apply(int argc, const char **argv, const char *unused_prefix)
        int read_stdin = 1;
        int inaccurate_eof = 0;
        int errs = 0;
-       int is_not_gitdir = 0;
+       int is_not_gitdir;
 
        const char *whitespace_option = NULL;
 
@@ -3118,7 +3121,7 @@ int cmd_apply(int argc, const char **argv, const char *unused_prefix)
 
                fd = open(arg, O_RDONLY);
                if (fd < 0)
-                       usage(apply_usage);
+                       die("can't open patch '%s': %s", arg, strerror(errno));
                read_stdin = 0;
                set_default_whitespace_mode(whitespace_option);
                errs |= apply_patch(fd, arg, inaccurate_eof);