From c0537662806f4b3d3ba883d05a48fdf9120893f0 Mon Sep 17 00:00:00 2001 From: Christian Couder Date: Sat, 9 May 2009 17:55:45 +0200 Subject: [PATCH] bisect: implement the "check_merge_bases" function And all functions needed to make it work. This is a port from the shell function with the same name "git-bisect.sh". This function is not used yet but it will be used later. Signed-off-by: Christian Couder Signed-off-by: Junio C Hamano --- bisect.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 130 insertions(+) diff --git a/bisect.c b/bisect.c index d2a34d1e5..b24ee78ba 100644 --- a/bisect.c +++ b/bisect.c @@ -507,6 +507,20 @@ static int lookup_sha1_array(struct sha1_array *array, return sha1_pos(sha1, array->sha1, array->sha1_nr, sha1_access); } +static char *join_sha1_array_hex(struct sha1_array *array, char delim) +{ + struct strbuf joined_hexs = STRBUF_INIT; + int i; + + for (i = 0; i < array->sha1_nr; i++) { + strbuf_addstr(&joined_hexs, sha1_to_hex(array->sha1[i])); + if (i + 1 < array->sha1_nr) + strbuf_addch(&joined_hexs, delim); + } + + return strbuf_detach(&joined_hexs, NULL); +} + struct commit_list *filter_skipped(struct commit_list *list, struct commit_list **tried, int show_all) @@ -587,6 +601,30 @@ static void exit_if_skipped_commits(struct commit_list *tried, exit(2); } +static int is_expected_rev(const unsigned char *sha1) +{ + const char *filename = git_path("BISECT_EXPECTED_REV"); + struct stat st; + struct strbuf str = STRBUF_INIT; + FILE *fp; + int res = 0; + + if (stat(filename, &st) || !S_ISREG(st.st_mode)) + return 0; + + fp = fopen(filename, "r"); + if (!fp) + return 0; + + if (strbuf_getline(&str, fp, '\n') != EOF) + res = !strcmp(str.buf, sha1_to_hex(sha1)); + + strbuf_release(&str); + fclose(fp); + + return res; +} + static void mark_expected_rev(char *bisect_rev_hex) { int len = strlen(bisect_rev_hex); @@ -620,6 +658,98 @@ static int bisect_checkout(char *bisect_rev_hex) return run_command_v_opt(argv_show_branch, RUN_GIT_CMD); } +static struct commit *get_commit_reference(const unsigned char *sha1) +{ + struct commit *r = lookup_commit_reference(sha1); + if (!r) + die("Not a valid commit name %s", sha1_to_hex(sha1)); + return r; +} + +static struct commit **get_bad_and_good_commits(int *rev_nr) +{ + int len = 1 + good_revs.sha1_nr; + struct commit **rev = xmalloc(len * sizeof(*rev)); + int i, n = 0; + + rev[n++] = get_commit_reference(current_bad_sha1); + for (i = 0; i < good_revs.sha1_nr; i++) + rev[n++] = get_commit_reference(good_revs.sha1[i]); + *rev_nr = n; + + return rev; +} + +static void handle_bad_merge_base(void) +{ + if (is_expected_rev(current_bad_sha1)) { + char *bad_hex = sha1_to_hex(current_bad_sha1); + char *good_hex = join_sha1_array_hex(&good_revs, ' '); + + fprintf(stderr, "The merge base %s is bad.\n" + "This means the bug has been fixed " + "between %s and [%s].\n", + bad_hex, bad_hex, good_hex); + + exit(3); + } + + fprintf(stderr, "Some good revs are not ancestor of the bad rev.\n" + "git bisect cannot work properly in this case.\n" + "Maybe you mistake good and bad revs?\n"); + exit(1); +} + +void handle_skipped_merge_base(const unsigned char *mb) +{ + char *mb_hex = sha1_to_hex(mb); + char *bad_hex = sha1_to_hex(current_bad_sha1); + char *good_hex = join_sha1_array_hex(&good_revs, ' '); + + fprintf(stderr, "Warning: the merge base between %s and [%s] " + "must be skipped.\n" + "So we cannot be sure the first bad commit is " + "between %s and %s.\n" + "We continue anyway.\n", + bad_hex, good_hex, mb_hex, bad_hex); + free(good_hex); +} + +/* + * "check_merge_bases" checks that merge bases are not "bad". + * + * - If one is "bad", it means the user assumed something wrong + * and we must exit with a non 0 error code. + * - If one is "good", 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. + */ +static void check_merge_bases(void) +{ + struct commit_list *result; + int rev_nr; + struct commit **rev = get_bad_and_good_commits(&rev_nr); + + result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1, 0); + + for (; result; result = result->next) { + const unsigned char *mb = result->item->object.sha1; + if (!hashcmp(mb, current_bad_sha1)) { + handle_bad_merge_base(); + } else if (0 <= lookup_sha1_array(&good_revs, mb)) { + continue; + } else if (0 <= lookup_sha1_array(&skipped_revs, mb)) { + handle_skipped_merge_base(mb); + } else { + printf("Bisecting: a merge base must be tested\n"); + exit(bisect_checkout(sha1_to_hex(mb))); + } + } + + free(rev); + free_commit_list(result); +} + /* * We use the convention that exiting with an exit code 10 means that * the bisection process finished successfully. -- 2.30.2