builtin/apply: make parse_chunk() return a negative integer on error

To libify `git apply` functionality we have to signal errors to the
caller instead of die()ing or exit()ing.

To do that in a compatible manner with the rest of the error handling
in builtin/apply.c, parse_chunk() should return a negative integer
instead of calling die() or exit().

As parse_chunk() is called only by apply_patch() which already
returns either -1 or -128 when an error happened, let's make it also
return -1 or -128.

This makes it compatible with what find_header() and parse_binary()
already return.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/apply.c b/builtin/apply.c
index 434ba0c5429d53a196dbf9b8dd707181c6f13bac..c07d142be8e82eec8ae65375d6e4219e196f6897 100644 (file)
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -1996,22 +1996,22 @@ static int use_patch(struct apply_state *state, struct patch *p)
        return !state->has_include;
 }
 
-
 /*
  * Read the patch text in "buffer" that extends for "size" bytes; stop
  * reading after seeing a single patch (i.e. changes to a single file).
  * Create fragments (i.e. patch hunks) and hang them to the given patch.
- * Return the number of bytes consumed, so that the caller can call us
- * again for the next patch.
+ *
+ * Returns:
+ *   -1 if no header was found or parse_binary() failed,
+ *   -128 on another error,
+ *   the number of bytes consumed otherwise,
+ *     so that the caller can call us again for the next patch.
  */
 static int parse_chunk(struct apply_state *state, char *buffer, unsigned long size, struct patch *patch)
 {
        int hdrsize, patchsize;
        int offset = find_header(state, buffer, size, &hdrsize, patch);
 
-       if (offset == -128)
-               exit(128);
-
        if (offset < 0)
                return offset;
 
@@ -2071,8 +2071,10 @@ static int parse_chunk(struct apply_state *state, char *buffer, unsigned long si
                 * empty to us here.
                 */
                if ((state->apply || state->check) &&
-                   (!patch->is_binary && !metadata_changes(patch)))
-                       die(_("patch with only garbage at line %d"), state->linenr);
+                   (!patch->is_binary && !metadata_changes(patch))) {
+                       error(_("patch with only garbage at line %d"), state->linenr);
+                       return -128;
+               }
        }
 
        return offset + hdrsize + patchsize;
@@ -4455,6 +4457,10 @@ static int apply_patch(struct apply_state *state,
                nr = parse_chunk(state, buf.buf + offset, buf.len - offset, patch);
                if (nr < 0) {
                        free_patch(patch);
+                       if (nr == -128) {
+                               res = -128;
+                               goto end;
+                       }
                        break;
                }
                if (state->apply_in_reverse)