]> git.ipfire.org Git - thirdparty/git.git/blobdiff - bisect.c
t4216: avoid unnecessary subshell in test_bloom_filters_not_used
[thirdparty/git.git] / bisect.c
index e81c91d02c07552dd50e82d42ae3e14f81945e01..9154f810f76af3cdbf82b8bb509f47aa392b0e01 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -572,7 +572,7 @@ static int sqrti(int val)
 {
        float d, x = val;
 
-       if (val == 0)
+       if (!val)
                return 0;
 
        do {
@@ -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)
@@ -703,9 +704,10 @@ static int is_expected_rev(const struct object_id *oid)
        return res;
 }
 
-static int bisect_checkout(const struct object_id *bisect_rev, int no_checkout)
+static enum bisect_error bisect_checkout(const struct object_id *bisect_rev, int no_checkout)
 {
        char bisect_rev_hex[GIT_MAX_HEXSZ + 1];
+       enum bisect_error res = BISECT_OK;
 
        memcpy(bisect_rev_hex, oid_to_hex(bisect_rev), the_hash_algo->hexsz + 1);
        update_ref(NULL, "BISECT_EXPECTED_REV", bisect_rev, NULL, 0, UPDATE_REFS_DIE_ON_ERR);
@@ -715,14 +717,24 @@ static int bisect_checkout(const struct object_id *bisect_rev, int no_checkout)
                update_ref(NULL, "BISECT_HEAD", bisect_rev, NULL, 0,
                           UPDATE_REFS_DIE_ON_ERR);
        } else {
-               int res;
                res = run_command_v_opt(argv_checkout, RUN_GIT_CMD);
                if (res)
-                       exit(res);
+                       /*
+                        * Errors in `run_command()` itself, signaled by res < 0,
+                        * and errors in the child process, signaled by res > 0
+                        * can both be treated as regular BISECT_FAILURE (-1).
+                        */
+                       return -abs(res);
        }
 
        argv_show_branch[1] = bisect_rev_hex;
-       return run_command_v_opt(argv_show_branch, RUN_GIT_CMD);
+       res = run_command_v_opt(argv_show_branch, RUN_GIT_CMD);
+       /*
+        * Errors in `run_command()` itself, signaled by res < 0,
+        * and errors in the child process, signaled by res > 0
+        * can both be treated as regular BISECT_FAILURE (-1).
+        */
+       return -abs(res);
 }
 
 static struct commit *get_commit_reference(struct repository *r,
@@ -749,7 +761,7 @@ static struct commit **get_bad_and_good_commits(struct repository *r,
        return rev;
 }
 
-static void handle_bad_merge_base(void)
+static enum bisect_error handle_bad_merge_base(void)
 {
        if (is_expected_rev(current_bad_oid)) {
                char *bad_hex = oid_to_hex(current_bad_oid);
@@ -770,14 +782,14 @@ static void handle_bad_merge_base(void)
                                "between %s and [%s].\n"),
                                bad_hex, term_bad, term_good, bad_hex, good_hex);
                }
-               exit(3);
+               return BISECT_MERGE_BASE_CHECK;
        }
 
        fprintf(stderr, _("Some %s revs are not ancestors of the %s rev.\n"
                "git bisect cannot work properly in this case.\n"
                "Maybe you mistook %s and %s revs?\n"),
                term_good, term_bad, term_good, term_bad);
-       exit(1);
+       return BISECT_FAILED;
 }
 
 static void handle_skipped_merge_base(const struct object_id *mb)
@@ -799,13 +811,18 @@ static void handle_skipped_merge_base(const struct object_id *mb)
  * "check_merge_bases" checks that merge bases are not "bad" (or "new").
  *
  * - If one is "bad" (or "new"), it means the user assumed something wrong
- * and we must exit with a non 0 error code.
+ * and we must return error with a non 0 error code.
  * - If one is "good" (or "old"), that's good, we have nothing to do.
  * - If one is "skipped", we can't know but we should warn.
  * - If we don't know, we should check it out and ask the user to test.
+ * - If a merge base must be tested, on success return
+ * BISECT_INTERNAL_SUCCESS_MERGE_BASE (-11) a special condition
+ * for early success, this will be converted back to 0 in
+ * check_good_are_ancestors_of_bad().
  */
-static void check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
+static enum bisect_error check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
 {
+       enum bisect_error res = BISECT_OK;
        struct commit_list *result;
 
        result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1);
@@ -813,18 +830,24 @@ static void check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
        for (; result; result = result->next) {
                const struct object_id *mb = &result->item->object.oid;
                if (oideq(mb, current_bad_oid)) {
-                       handle_bad_merge_base();
+                       res = handle_bad_merge_base();
+                       break;
                } else if (0 <= oid_array_lookup(&good_revs, mb)) {
                        continue;
                } else if (0 <= oid_array_lookup(&skipped_revs, mb)) {
                        handle_skipped_merge_base(mb);
                } else {
                        printf(_("Bisecting: a merge base must be tested\n"));
-                       exit(bisect_checkout(mb, no_checkout));
+                       res = bisect_checkout(mb, no_checkout);
+                       if (!res)
+                               /* indicate early success */
+                               res = BISECT_INTERNAL_SUCCESS_MERGE_BASE;
+                       break;
                }
        }
 
        free_commit_list(result);
+       return res;
 }
 
 static int check_ancestors(struct repository *r, int rev_nr,
@@ -850,43 +873,58 @@ static int check_ancestors(struct repository *r, int rev_nr,
  *
  * If that's not the case, we need to check the merge bases.
  * If a merge base must be tested by the user, its source code will be
- * checked out to be tested by the user and we will exit.
+ * checked out to be tested by the user and we will return.
  */
-static void check_good_are_ancestors_of_bad(struct repository *r,
+
+static enum bisect_error check_good_are_ancestors_of_bad(struct repository *r,
                                            const char *prefix,
                                            int no_checkout)
 {
-       char *filename = git_pathdup("BISECT_ANCESTORS_OK");
+       char *filename;
        struct stat st;
        int fd, rev_nr;
+       enum bisect_error res = BISECT_OK;
        struct commit **rev;
 
        if (!current_bad_oid)
-               die(_("a %s revision is needed"), term_bad);
+               return error(_("a %s revision is needed"), term_bad);
+
+       filename = git_pathdup("BISECT_ANCESTORS_OK");
 
        /* Check if file BISECT_ANCESTORS_OK exists. */
        if (!stat(filename, &st) && S_ISREG(st.st_mode))
                goto done;
 
        /* Bisecting with no good rev is ok. */
-       if (good_revs.nr == 0)
+       if (!good_revs.nr)
                goto done;
 
        /* Check if all good revs are ancestor of the bad rev. */
+
        rev = get_bad_and_good_commits(r, &rev_nr);
        if (check_ancestors(r, rev_nr, rev, prefix))
-               check_merge_bases(rev_nr, rev, no_checkout);
+               res = check_merge_bases(rev_nr, rev, no_checkout);
        free(rev);
 
-       /* Create file BISECT_ANCESTORS_OK. */
-       fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
-       if (fd < 0)
-               warning_errno(_("could not create file '%s'"),
-                             filename);
-       else
-               close(fd);
+       if (!res) {
+               /* Create file BISECT_ANCESTORS_OK. */
+               fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
+               if (fd < 0)
+                       /*
+                        * BISECT_ANCESTORS_OK file is not absolutely necessary,
+                        * the bisection process will continue at the next
+                        * bisection step.
+                        * So, just signal with a warning that something
+                        * might be wrong.
+                        */
+                       warning_errno(_("could not create file '%s'"),
+                               filename);
+               else
+                       close(fd);
+       }
  done:
        free(filename);
+       return res;
 }
 
 /*
@@ -938,18 +976,19 @@ void read_bisect_terms(const char **read_bad, const char **read_good)
 }
 
 /*
- * We use the convention that exiting with an exit code 10 means that
+ * We use the convention that return BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND (-10) means
  * the bisection process finished successfully.
- * In this case the calling shell script should exit 0.
- *
+ * In this case the calling function or command should not turn a
+ * BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND return code into an error or a non zero exit code.
  * If no_checkout is non-zero, the bisection process does not
  * checkout the trial commit but instead simply updates BISECT_HEAD.
  */
-int bisect_next_all(struct repository *r, const char *prefix, int no_checkout)
+enum bisect_error bisect_next_all(struct repository *r, const char *prefix, int no_checkout)
 {
        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;
 
@@ -957,7 +996,9 @@ int bisect_next_all(struct repository *r, const char *prefix, int no_checkout)
        if (read_bisect_refs())
                die(_("reading bisect refs failed"));
 
-       check_good_are_ancestors_of_bad(r, prefix, no_checkout);
+       res = check_good_are_ancestors_of_bad(r, prefix, no_checkout);
+       if (res)
+               return res;
 
        bisect_rev_setup(r, &revs, prefix, "%s", "^%s", 1);
        revs.limited = 1;
@@ -969,33 +1010,45 @@ int bisect_next_all(struct repository *r, const char *prefix, int no_checkout)
 
        if (!revs.commits) {
                /*
-                * We should exit here only if the "bad"
+                * We should return error 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)
+                       return res;
                printf(_("%s was both %s and %s\n"),
                       oid_to_hex(current_bad_oid),
                       term_good,
                       term_bad);
-               exit(1);
+
+               return BISECT_FAILED;
        }
 
        if (!all) {
                fprintf(stderr, _("No testable commit found.\n"
                        "Maybe you started with bad path parameters?\n"));
-               exit(4);
+
+               return BISECT_NO_TESTABLE_COMMIT;
        }
 
        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)
+                       return res;
                printf("%s is the first %s commit\n", oid_to_hex(bisect_rev),
                        term_bad);
+
                show_diff_tree(r, prefix, revs.commits->item);
-               /* This means the bisection process succeeded. */
-               exit(10);
+               /*
+                * This means the bisection process succeeded.
+                * Using BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND (-10)
+                * so that the call chain can simply check
+                * for negative return values for early returns up
+                * until the cmd_bisect__helper() caller.
+                */
+               return BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
        }
 
        nr = all - reaches - 1;