bisect: libify `exit_if_skipped_commits` to `error_if_skipped*` and its dependents

Since we want to get rid of git-bisect.sh, it would be necessary to
convert those exit() calls to return statements so that errors can be
reported.

Emulate try catch in C by converting `exit(<positive-value>)` to
`return <negative-value>`. Follow POSIX conventions to return
<negative-value> to indicate error.

Update all callers to handle the error returns.

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Pranit Bauva <pranit.bauva@gmail.com>
Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/bisect.c b/bisect.c
index e4573c7ba15c6a55dd286ea64cfb5f925b16b056..85bda3500b26ae02b840d9ba88c2576bda835074 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -661,11 +661,11 @@ static void bisect_common(struct rev_info *revs)
                mark_edges_uninteresting(revs, NULL, 0);
 }
 
-static void exit_if_skipped_commits(struct commit_list *tried,
+static enum bisect_error error_if_skipped_commits(struct commit_list *tried,
                                    const struct object_id *bad)
 {
        if (!tried)
-               return;
+               return BISECT_OK;
 
        printf("There are only 'skip'ped commits left to test.\n"
               "The first %s commit could be any of:\n", term_bad);
@@ -676,7 +676,8 @@ static void exit_if_skipped_commits(struct commit_list *tried,
        if (bad)
                printf("%s\n", oid_to_hex(bad));
        printf(_("We cannot bisect more!\n"));
-       exit(2);
+
+       return BISECT_ONLY_SKIPPED_LEFT;
 }
 
 static int is_expected_rev(const struct object_id *oid)
@@ -950,6 +951,7 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix, int
        struct rev_info revs;
        struct commit_list *tried;
        int reaches = 0, all = 0, nr, steps;
+       enum bisect_error res = BISECT_OK;
        struct object_id *bisect_rev;
        char *steps_msg;
 
@@ -972,8 +974,9 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix, int
                 * We should exit here only if the "bad"
                 * commit is also a "skip" commit.
                 */
-               exit_if_skipped_commits(tried, NULL);
-
+               res = error_if_skipped_commits(tried, NULL);
+               if (res < 0)
+                       exit(-res);
                printf(_("%s was both %s and %s\n"),
                       oid_to_hex(current_bad_oid),
                       term_good,
@@ -990,7 +993,9 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix, int
        bisect_rev = &revs.commits->item->object.oid;
 
        if (oideq(bisect_rev, current_bad_oid)) {
-               exit_if_skipped_commits(tried, current_bad_oid);
+               res = error_if_skipped_commits(tried, current_bad_oid);
+               if (res)
+                       exit(-res);
                printf("%s is the first %s commit\n", oid_to_hex(bisect_rev),
                        term_bad);
                show_diff_tree(r, prefix, revs.commits->item);

diff --git a/bisect.h b/bisect.h
index c921ead02c5c75d1a232af1f737aa5f60e99eb22..19d90e4870e3a4c9610a42d8deaede55b763736e 100644 (file)
--- a/bisect.h
+++ b/bisect.h
@@ -37,10 +37,13 @@ struct rev_list_info {
  * commit has been found (and possibly checked out) and it
  * should be tested.
  * BISECT_FAILED error code: default error code.
+ * BISECT_ONLY_SKIPPED_LEFT error code: only skipped
+ * commits left to be tested.
  */
 enum bisect_error {
        BISECT_OK = 0,
-       BISECT_FAILED = -1
+       BISECT_FAILED = -1,
+       BISECT_ONLY_SKIPPED_LEFT = -2
 };
 
 enum bisect_error bisect_next_all(struct repository *r,