test-lib: fail if invalid options are passed
[gitweb.git] / bisect.c
index 58f7e6f7738def184072247f934cce06d349c91d..c43c120bdefe95bda60b913c5a52d0a942e9d3f6 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -6,15 +6,30 @@
 #include "list-objects.h"
 #include "quote.h"
 #include "sha1-lookup.h"
+#include "run-command.h"
 #include "bisect.h"
 
-static unsigned char (*skipped_sha1)[20];
-static int skipped_sha1_nr;
-static int skipped_sha1_alloc;
+struct sha1_array {
+       unsigned char (*sha1)[20];
+       int sha1_nr;
+       int sha1_alloc;
+       int sorted;
+};
+
+static struct sha1_array good_revs;
+static struct sha1_array skipped_revs;
+
+static const unsigned char *current_bad_sha1;
+
+struct argv_array {
+       const char **argv;
+       int argv_nr;
+       int argv_alloc;
+};
 
-static const char **rev_argv;
-static int rev_argv_nr;
-static int rev_argv_alloc;
+static const char *argv_diff_tree[] = {"diff-tree", "--pretty", NULL, NULL};
+static const char *argv_checkout[] = {"checkout", "-q", NULL, "--", NULL};
+static const char *argv_show_branch[] = {"show-branch", NULL, NULL};
 
 /* bits #0-15 in revision.h */
 
@@ -398,23 +413,37 @@ struct commit_list *find_bisection(struct commit_list *list,
        return best;
 }
 
+static void argv_array_push(struct argv_array *array, const char *string)
+{
+       ALLOC_GROW(array->argv, array->argv_nr + 1, array->argv_alloc);
+       array->argv[array->argv_nr++] = string;
+}
+
+static void argv_array_push_sha1(struct argv_array *array,
+                                const unsigned char *sha1,
+                                const char *format)
+{
+       struct strbuf buf = STRBUF_INIT;
+       strbuf_addf(&buf, format, sha1_to_hex(sha1));
+       argv_array_push(array, strbuf_detach(&buf, NULL));
+}
+
+static void sha1_array_push(struct sha1_array *array,
+                           const unsigned char *sha1)
+{
+       ALLOC_GROW(array->sha1, array->sha1_nr + 1, array->sha1_alloc);
+       hashcpy(array->sha1[array->sha1_nr++], sha1);
+}
+
 static int register_ref(const char *refname, const unsigned char *sha1,
                        int flags, void *cb_data)
 {
        if (!strcmp(refname, "bad")) {
-               ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
-               rev_argv[rev_argv_nr++] = xstrdup(sha1_to_hex(sha1));
+               current_bad_sha1 = sha1;
        } else if (!prefixcmp(refname, "good-")) {
-               const char *hex = sha1_to_hex(sha1);
-               char *good = xmalloc(strlen(hex) + 2);
-               *good = '^';
-               memcpy(good + 1, hex, strlen(hex) + 1);
-               ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
-               rev_argv[rev_argv_nr++] = good;
+               sha1_array_push(&good_revs, sha1);
        } else if (!prefixcmp(refname, "skip-")) {
-               ALLOC_GROW(skipped_sha1, skipped_sha1_nr + 1,
-                          skipped_sha1_alloc);
-               hashcpy(skipped_sha1[skipped_sha1_nr++], sha1);
+               sha1_array_push(&skipped_revs, sha1);
        }
 
        return 0;
@@ -425,7 +454,7 @@ static int read_bisect_refs(void)
        return for_each_ref_in("refs/bisect/", register_ref, NULL);
 }
 
-void read_bisect_paths(void)
+void read_bisect_paths(struct argv_array *array)
 {
        struct strbuf str = STRBUF_INIT;
        const char *filename = git_path("BISECT_NAMES");
@@ -440,8 +469,8 @@ void read_bisect_paths(void)
 
                strbuf_trim(&str);
                quoted = strbuf_detach(&str, NULL);
-               res = sq_dequote_to_argv(quoted, &rev_argv,
-                                        &rev_argv_nr, &rev_argv_alloc);
+               res = sq_dequote_to_argv(quoted, &array->argv,
+                                        &array->argv_nr, &array->argv_alloc);
                if (res)
                        die("Badly quoted content in file '%s': %s",
                            filename, quoted);
@@ -451,26 +480,45 @@ void read_bisect_paths(void)
        fclose(fp);
 }
 
-static int skipcmp(const void *a, const void *b)
+static int array_cmp(const void *a, const void *b)
 {
        return hashcmp(a, b);
 }
 
-static void prepare_skipped(void)
+static void sort_sha1_array(struct sha1_array *array)
 {
-       qsort(skipped_sha1, skipped_sha1_nr, sizeof(*skipped_sha1), skipcmp);
+       qsort(array->sha1, array->sha1_nr, sizeof(*array->sha1), array_cmp);
+
+       array->sorted = 1;
 }
 
-static const unsigned char *skipped_sha1_access(size_t index, void *table)
+static const unsigned char *sha1_access(size_t index, void *table)
 {
-       unsigned char (*skipped)[20] = table;
-       return skipped[index];
+       unsigned char (*array)[20] = table;
+       return array[index];
 }
 
-static int lookup_skipped(unsigned char *sha1)
+static int lookup_sha1_array(struct sha1_array *array,
+                            const unsigned char *sha1)
 {
-       return sha1_pos(sha1, skipped_sha1, skipped_sha1_nr,
-                       skipped_sha1_access);
+       if (!array->sorted)
+               sort_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,
@@ -481,15 +529,14 @@ struct commit_list *filter_skipped(struct commit_list *list,
 
        *tried = NULL;
 
-       if (!skipped_sha1_nr)
+       if (!skipped_revs.sha1_nr)
                return list;
 
-       prepare_skipped();
-
        while (list) {
                struct commit_list *next = list->next;
                list->next = NULL;
-               if (0 <= lookup_skipped(list->item->object.sha1)) {
+               if (0 <= lookup_sha1_array(&skipped_revs,
+                                          list->item->object.sha1)) {
                        /* Move current to tried list */
                        *tried = list;
                        tried = &list->next;
@@ -506,51 +553,323 @@ struct commit_list *filter_skipped(struct commit_list *list,
        return filtered;
 }
 
-static void bisect_rev_setup(struct rev_info *revs, const char *prefix)
+static void bisect_rev_setup(struct rev_info *revs, const char *prefix,
+                            const char *bad_format, const char *good_format,
+                            int read_paths)
 {
+       struct argv_array rev_argv = { NULL, 0, 0 };
+       int i;
+
        init_revisions(revs, prefix);
        revs->abbrev = 0;
        revs->commit_format = CMIT_FMT_UNSPECIFIED;
 
-       /* argv[0] will be ignored by setup_revisions */
-       ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
-       rev_argv[rev_argv_nr++] = xstrdup("bisect_rev_setup");
+       /* rev_argv.argv[0] will be ignored by setup_revisions */
+       argv_array_push(&rev_argv, xstrdup("bisect_rev_setup"));
+       argv_array_push_sha1(&rev_argv, current_bad_sha1, bad_format);
+       for (i = 0; i < good_revs.sha1_nr; i++)
+               argv_array_push_sha1(&rev_argv, good_revs.sha1[i],
+                                    good_format);
+       argv_array_push(&rev_argv, xstrdup("--"));
+       if (read_paths)
+               read_bisect_paths(&rev_argv);
+       argv_array_push(&rev_argv, NULL);
+
+       setup_revisions(rev_argv.argv_nr, rev_argv.argv, revs, NULL);
+}
 
-       if (read_bisect_refs())
-               die("reading bisect refs failed");
+static void bisect_common(struct rev_info *revs)
+{
+       if (prepare_revision_walk(revs))
+               die("revision walk setup failed");
+       if (revs->tree_objects)
+               mark_edges_uninteresting(revs->commits, revs, NULL);
+}
+
+static void exit_if_skipped_commits(struct commit_list *tried,
+                                   const unsigned char *bad)
+{
+       if (!tried)
+               return;
+
+       printf("There are only 'skip'ped commits left to test.\n"
+              "The first bad commit could be any of:\n");
+       print_commit_list(tried, "%s\n", "%s\n");
+       if (bad)
+               printf("%s\n", sha1_to_hex(bad));
+       printf("We cannot bisect more!\n");
+       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);
+       const char *filename = git_path("BISECT_EXPECTED_REV");
+       int fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
+
+       if (fd < 0)
+               die("could not create file '%s': %s",
+                   filename, strerror(errno));
 
-       ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
-       rev_argv[rev_argv_nr++] = xstrdup("--");
+       bisect_rev_hex[len] = '\n';
+       write_or_die(fd, bisect_rev_hex, len + 1);
+       bisect_rev_hex[len] = '\0';
 
-       read_bisect_paths();
+       if (close(fd) < 0)
+               die("closing file %s: %s", filename, strerror(errno));
+}
+
+static int bisect_checkout(char *bisect_rev_hex)
+{
+       int res;
 
-       ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
-       rev_argv[rev_argv_nr++] = NULL;
+       mark_expected_rev(bisect_rev_hex);
 
-       setup_revisions(rev_argv_nr, rev_argv, revs, NULL);
+       argv_checkout[2] = bisect_rev_hex;
+       res = run_command_v_opt(argv_checkout, RUN_GIT_CMD);
+       if (res)
+               exit(res);
 
-       revs->limited = 1;
+       argv_show_branch[1] = bisect_rev_hex;
+       return run_command_v_opt(argv_show_branch, RUN_GIT_CMD);
 }
 
-int bisect_next_vars(const char *prefix)
+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);
+}
+
+static int check_ancestors(const char *prefix)
 {
        struct rev_info revs;
-       struct rev_list_info info;
-       int reaches = 0, all = 0;
+       struct object_array pending_copy;
+       int i, res;
 
-       memset(&info, 0, sizeof(info));
-       info.revs = &revs;
-       info.bisect_show_flags = BISECT_SHOW_TRIED | BISECT_SHOW_STRINGED;
+       bisect_rev_setup(&revs, prefix, "^%s", "%s", 0);
 
-       bisect_rev_setup(&revs, prefix);
+       /* Save pending objects, so they can be cleaned up later. */
+       memset(&pending_copy, 0, sizeof(pending_copy));
+       for (i = 0; i < revs.pending.nr; i++)
+               add_object_array(revs.pending.objects[i].item,
+                                revs.pending.objects[i].name,
+                                &pending_copy);
 
-       if (prepare_revision_walk(&revs))
-               die("revision walk setup failed");
-       if (revs.tree_objects)
-               mark_edges_uninteresting(revs.commits, &revs, NULL);
+       bisect_common(&revs);
+       res = (revs.commits != NULL);
+
+       /* Clean up objects used, as they will be reused. */
+       for (i = 0; i < pending_copy.nr; i++) {
+               struct object *o = pending_copy.objects[i].item;
+               unparse_commit((struct commit *)o);
+       }
+
+       return res;
+}
+
+/*
+ * "check_good_are_ancestors_of_bad" checks that all "good" revs are
+ * ancestor of the "bad" rev.
+ *
+ * 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.
+ */
+static void check_good_are_ancestors_of_bad(const char *prefix)
+{
+       const char *filename = git_path("BISECT_ANCESTORS_OK");
+       struct stat st;
+       int fd;
+
+       if (!current_bad_sha1)
+               die("a bad revision is needed");
+
+       /* Check if file BISECT_ANCESTORS_OK exists. */
+       if (!stat(filename, &st) && S_ISREG(st.st_mode))
+               return;
+
+       /* Bisecting with no good rev is ok. */
+       if (good_revs.sha1_nr == 0)
+               return;
+
+       /* Check if all good revs are ancestor of the bad rev. */
+       if (check_ancestors(prefix))
+               check_merge_bases();
+
+       /* Create file BISECT_ANCESTORS_OK. */
+       fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY, 0600);
+       if (fd < 0)
+               warning("could not create file '%s': %s",
+                       filename, strerror(errno));
+       else
+               close(fd);
+}
+
+/*
+ * We use the convention that exiting with an exit code 10 means that
+ * the bisection process finished successfully.
+ * In this case the calling shell script should exit 0.
+ */
+int bisect_next_all(const char *prefix)
+{
+       struct rev_info revs;
+       struct commit_list *tried;
+       int reaches = 0, all = 0, nr;
+       const unsigned char *bisect_rev;
+       char bisect_rev_hex[41];
+
+       if (read_bisect_refs())
+               die("reading bisect refs failed");
+
+       check_good_are_ancestors_of_bad(prefix);
+
+       bisect_rev_setup(&revs, prefix, "%s", "^%s", 1);
+       revs.limited = 1;
+
+       bisect_common(&revs);
 
        revs.commits = find_bisection(revs.commits, &reaches, &all,
-                                     !!skipped_sha1_nr);
+                                      !!skipped_revs.sha1_nr);
+       revs.commits = filter_skipped(revs.commits, &tried, 0);
+
+       if (!revs.commits) {
+               /*
+                * We should exit here only if the "bad"
+                * commit is also a "skip" commit.
+                */
+               exit_if_skipped_commits(tried, NULL);
+
+               printf("%s was both good and bad\n",
+                      sha1_to_hex(current_bad_sha1));
+               exit(1);
+       }
 
-       return show_bisect_vars(&info, reaches, all);
+       bisect_rev = revs.commits->item->object.sha1;
+       memcpy(bisect_rev_hex, sha1_to_hex(bisect_rev), 41);
+
+       if (!hashcmp(bisect_rev, current_bad_sha1)) {
+               exit_if_skipped_commits(tried, current_bad_sha1);
+               printf("%s is first bad commit\n", bisect_rev_hex);
+               argv_diff_tree[2] = bisect_rev_hex;
+               run_command_v_opt(argv_diff_tree, RUN_GIT_CMD);
+               /* This means the bisection process succeeded. */
+               exit(10);
+       }
+
+       nr = all - reaches - 1;
+       printf("Bisecting: %d revisions left to test after this "
+              "(roughly %d steps)\n", nr, estimate_bisect_steps(all));
+
+       return bisect_checkout(bisect_rev_hex);
 }
+