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-rw-r--r--bisect.c241
1 files changed, 159 insertions, 82 deletions
diff --git a/bisect.c b/bisect.c
index 6e186e29cc..053d1a2ab9 100644
--- a/bisect.c
+++ b/bisect.c
@@ -15,14 +15,15 @@
static struct sha1_array good_revs;
static struct sha1_array skipped_revs;
-static const unsigned char *current_bad_sha1;
+static struct object_id *current_bad_oid;
static const char *argv_checkout[] = {"checkout", "-q", NULL, "--", NULL};
static const char *argv_show_branch[] = {"show-branch", NULL, NULL};
-static const char *argv_update_ref[] = {"update-ref", "--no-deref", "BISECT_HEAD", NULL, NULL};
-/* bits #0-15 in revision.h */
+static const char *term_bad;
+static const char *term_good;
+/* Remember to update object flag allocation in object.h */
#define COUNTED (1u<<16)
/*
@@ -216,11 +217,12 @@ static struct commit_list *best_bisection_sorted(struct commit_list *list, int n
}
qsort(array, cnt, sizeof(*array), compare_commit_dist);
for (p = list, i = 0; i < cnt; i++) {
- struct name_decoration *r = xmalloc(sizeof(*r) + 100);
+ char buf[100]; /* enough for dist=%d */
struct object *obj = &(array[i].commit->object);
- sprintf(r->name, "dist=%d", array[i].distance);
- r->next = add_decoration(&name_decoration, obj, r);
+ snprintf(buf, sizeof(buf), "dist=%d", array[i].distance);
+ add_name_decoration(DECORATION_NONE, buf, obj);
+
p->item = array[i].commit;
p = p->next;
}
@@ -400,17 +402,24 @@ struct commit_list *find_bisection(struct commit_list *list,
return best;
}
-static int register_ref(const char *refname, const unsigned char *sha1,
+static int register_ref(const char *refname, const struct object_id *oid,
int flags, void *cb_data)
{
- if (!strcmp(refname, "bad")) {
- current_bad_sha1 = sha1;
- } else if (!prefixcmp(refname, "good-")) {
- sha1_array_append(&good_revs, sha1);
- } else if (!prefixcmp(refname, "skip-")) {
- sha1_array_append(&skipped_revs, sha1);
+ struct strbuf good_prefix = STRBUF_INIT;
+ strbuf_addstr(&good_prefix, term_good);
+ strbuf_addstr(&good_prefix, "-");
+
+ if (!strcmp(refname, term_bad)) {
+ current_bad_oid = xmalloc(sizeof(*current_bad_oid));
+ oidcpy(current_bad_oid, oid);
+ } else if (starts_with(refname, good_prefix.buf)) {
+ sha1_array_append(&good_revs, oid->hash);
+ } else if (starts_with(refname, "skip-")) {
+ sha1_array_append(&skipped_revs, oid->hash);
}
+ strbuf_release(&good_prefix);
+
return 0;
}
@@ -419,10 +428,13 @@ static int read_bisect_refs(void)
return for_each_ref_in("refs/bisect/", register_ref, NULL);
}
+static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
+static GIT_PATH_FUNC(git_path_bisect_expected_rev, "BISECT_EXPECTED_REV")
+
static void read_bisect_paths(struct argv_array *array)
{
struct strbuf str = STRBUF_INIT;
- const char *filename = git_path("BISECT_NAMES");
+ const char *filename = git_path_bisect_names();
FILE *fp = fopen(filename, "r");
if (!fp)
@@ -525,9 +537,9 @@ struct commit_list *filter_skipped(struct commit_list *list,
* is increased by one between each call, but that should not matter
* for this application.
*/
-static int get_prn(int count) {
+static unsigned get_prn(unsigned count) {
count = count * 1103515245 + 12345;
- return ((unsigned)(count/65536) % PRN_MODULO);
+ return (count/65536) % PRN_MODULO;
}
/*
@@ -563,7 +575,7 @@ static struct commit_list *skip_away(struct commit_list *list, int count)
for (i = 0; cur; cur = cur->next, i++) {
if (i == index) {
- if (hashcmp(cur->item->object.sha1, current_bad_sha1))
+ if (hashcmp(cur->item->object.sha1, current_bad_oid->hash))
return cur;
if (previous)
return previous;
@@ -606,7 +618,7 @@ static void bisect_rev_setup(struct rev_info *revs, const char *prefix,
/* rev_argv.argv[0] will be ignored by setup_revisions */
argv_array_push(&rev_argv, "bisect_rev_setup");
- argv_array_pushf(&rev_argv, bad_format, sha1_to_hex(current_bad_sha1));
+ argv_array_pushf(&rev_argv, bad_format, oid_to_hex(current_bad_oid));
for (i = 0; i < good_revs.nr; i++)
argv_array_pushf(&rev_argv, good_format,
sha1_to_hex(good_revs.sha1[i]));
@@ -623,27 +635,27 @@ 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);
+ mark_edges_uninteresting(revs, NULL);
}
static void exit_if_skipped_commits(struct commit_list *tried,
- const unsigned char *bad)
+ const struct object_id *bad)
{
if (!tried)
return;
printf("There are only 'skip'ped commits left to test.\n"
- "The first bad commit could be any of:\n");
+ "The first %s commit could be any of:\n", term_bad);
print_commit_list(tried, "%s\n", "%s\n");
if (bad)
- printf("%s\n", sha1_to_hex(bad));
+ printf("%s\n", oid_to_hex(bad));
printf("We cannot bisect more!\n");
exit(2);
}
-static int is_expected_rev(const unsigned char *sha1)
+static int is_expected_rev(const struct object_id *oid)
{
- const char *filename = git_path("BISECT_EXPECTED_REV");
+ const char *filename = git_path_bisect_expected_rev();
struct stat st;
struct strbuf str = STRBUF_INIT;
FILE *fp;
@@ -657,7 +669,7 @@ static int is_expected_rev(const unsigned char *sha1)
return 0;
if (strbuf_getline(&str, fp, '\n') != EOF)
- res = !strcmp(str.buf, sha1_to_hex(sha1));
+ res = !strcmp(str.buf, oid_to_hex(oid));
strbuf_release(&str);
fclose(fp);
@@ -665,36 +677,18 @@ static int is_expected_rev(const unsigned char *sha1)
return res;
}
-static void mark_expected_rev(char *bisect_rev_hex)
+static int bisect_checkout(const unsigned char *bisect_rev, int no_checkout)
{
- 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);
+ char bisect_rev_hex[GIT_SHA1_HEXSZ + 1];
- if (fd < 0)
- die_errno("could not create file '%s'", filename);
-
- bisect_rev_hex[len] = '\n';
- write_or_die(fd, bisect_rev_hex, len + 1);
- bisect_rev_hex[len] = '\0';
-
- if (close(fd) < 0)
- die("closing file %s: %s", filename, strerror(errno));
-}
-
-static int bisect_checkout(char *bisect_rev_hex, int no_checkout)
-{
- int res;
-
- mark_expected_rev(bisect_rev_hex);
+ memcpy(bisect_rev_hex, sha1_to_hex(bisect_rev), GIT_SHA1_HEXSZ + 1);
+ update_ref(NULL, "BISECT_EXPECTED_REV", bisect_rev, NULL, 0, UPDATE_REFS_DIE_ON_ERR);
argv_checkout[2] = bisect_rev_hex;
if (no_checkout) {
- argv_update_ref[3] = bisect_rev_hex;
- if (run_command_v_opt(argv_update_ref, RUN_GIT_CMD))
- die("update-ref --no-deref HEAD failed on %s",
- bisect_rev_hex);
+ 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);
@@ -718,7 +712,7 @@ static struct commit **get_bad_and_good_commits(int *rev_nr)
struct commit **rev = xmalloc(len * sizeof(*rev));
int i, n = 0;
- rev[n++] = get_commit_reference(current_bad_sha1);
+ rev[n++] = get_commit_reference(current_bad_oid->hash);
for (i = 0; i < good_revs.nr; i++)
rev[n++] = get_commit_reference(good_revs.sha1[i]);
*rev_nr = n;
@@ -728,45 +722,56 @@ static struct commit **get_bad_and_good_commits(int *rev_nr)
static void handle_bad_merge_base(void)
{
- if (is_expected_rev(current_bad_sha1)) {
- char *bad_hex = sha1_to_hex(current_bad_sha1);
+ if (is_expected_rev(current_bad_oid)) {
+ char *bad_hex = oid_to_hex(current_bad_oid);
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);
-
+ if (!strcmp(term_bad, "bad") && !strcmp(term_good, "good")) {
+ 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);
+ } else if (!strcmp(term_bad, "new") && !strcmp(term_good, "old")) {
+ fprintf(stderr, "The merge base %s is new.\n"
+ "The property has changed "
+ "between %s and [%s].\n",
+ bad_hex, bad_hex, good_hex);
+ } else {
+ fprintf(stderr, "The merge base %s is %s.\n"
+ "This means the first '%s' commit is "
+ "between %s and [%s].\n",
+ bad_hex, term_bad, term_good, bad_hex, good_hex);
+ }
exit(3);
}
- fprintf(stderr, "Some good revs are not ancestor of the bad rev.\n"
+ fprintf(stderr, "Some %s revs are not ancestor of the %s rev.\n"
"git bisect cannot work properly in this case.\n"
- "Maybe you mistake good and bad revs?\n");
+ "Maybe you mistook %s and %s revs?\n",
+ term_good, term_bad, term_good, term_bad);
exit(1);
}
static 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 *bad_hex = sha1_to_hex(current_bad_oid->hash);
char *good_hex = join_sha1_array_hex(&good_revs, ' ');
warning("the merge base between %s and [%s] "
"must be skipped.\n"
- "So we cannot be sure the first bad commit is "
+ "So we cannot be sure the first %s commit is "
"between %s and %s.\n"
"We continue anyway.",
- bad_hex, good_hex, mb_hex, bad_hex);
+ bad_hex, good_hex, term_bad, mb_hex, bad_hex);
free(good_hex);
}
/*
- * "check_merge_bases" checks that merge bases are not "bad".
+ * "check_merge_bases" checks that merge bases are not "bad" (or "new").
*
- * - If one is "bad", it means the user assumed something wrong
+ * - If one is "bad" (or "new"), 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 "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.
*/
@@ -776,11 +781,11 @@ static void check_merge_bases(int no_checkout)
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);
+ result = get_merge_bases_many(rev[0], rev_nr - 1, rev + 1);
for (; result; result = result->next) {
const unsigned char *mb = result->item->object.sha1;
- if (!hashcmp(mb, current_bad_sha1)) {
+ if (!hashcmp(mb, current_bad_oid->hash)) {
handle_bad_merge_base();
} else if (0 <= sha1_array_lookup(&good_revs, mb)) {
continue;
@@ -788,7 +793,7 @@ static void check_merge_bases(int no_checkout)
handle_skipped_merge_base(mb);
} else {
printf("Bisecting: a merge base must be tested\n");
- exit(bisect_checkout(sha1_to_hex(mb), no_checkout));
+ exit(bisect_checkout(mb, no_checkout));
}
}
@@ -833,20 +838,20 @@ static int check_ancestors(const char *prefix)
*/
static void check_good_are_ancestors_of_bad(const char *prefix, int no_checkout)
{
- const char *filename = git_path("BISECT_ANCESTORS_OK");
+ char *filename = git_pathdup("BISECT_ANCESTORS_OK");
struct stat st;
int fd;
- if (!current_bad_sha1)
- die("a bad revision is needed");
+ if (!current_bad_oid)
+ die("a %s revision is needed", term_bad);
/* Check if file BISECT_ANCESTORS_OK exists. */
if (!stat(filename, &st) && S_ISREG(st.st_mode))
- return;
+ goto done;
/* Bisecting with no good rev is ok. */
if (good_revs.nr == 0)
- return;
+ goto done;
/* Check if all good revs are ancestor of the bad rev. */
if (check_ancestors(prefix))
@@ -859,6 +864,8 @@ static void check_good_are_ancestors_of_bad(const char *prefix, int no_checkout)
filename, strerror(errno));
else
close(fd);
+ done:
+ free(filename);
}
/*
@@ -887,6 +894,36 @@ static void show_diff_tree(const char *prefix, struct commit *commit)
}
/*
+ * The terms used for this bisect session are stored in BISECT_TERMS.
+ * We read them and store them to adapt the messages accordingly.
+ * Default is bad/good.
+ */
+void read_bisect_terms(const char **read_bad, const char **read_good)
+{
+ struct strbuf str = STRBUF_INIT;
+ const char *filename = git_path("BISECT_TERMS");
+ FILE *fp = fopen(filename, "r");
+
+ if (!fp) {
+ if (errno == ENOENT) {
+ *read_bad = "bad";
+ *read_good = "good";
+ return;
+ } else {
+ die("could not read file '%s': %s", filename,
+ strerror(errno));
+ }
+ } else {
+ strbuf_getline(&str, fp, '\n');
+ *read_bad = strbuf_detach(&str, NULL);
+ strbuf_getline(&str, fp, '\n');
+ *read_good = strbuf_detach(&str, NULL);
+ }
+ strbuf_release(&str);
+ fclose(fp);
+}
+
+/*
* 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.
@@ -900,8 +937,8 @@ int bisect_next_all(const char *prefix, int no_checkout)
struct commit_list *tried;
int reaches = 0, all = 0, nr, steps;
const unsigned char *bisect_rev;
- char bisect_rev_hex[41];
+ read_bisect_terms(&term_bad, &term_good);
if (read_bisect_refs())
die("reading bisect refs failed");
@@ -923,8 +960,10 @@ int bisect_next_all(const char *prefix, int no_checkout)
*/
exit_if_skipped_commits(tried, NULL);
- printf("%s was both good and bad\n",
- sha1_to_hex(current_bad_sha1));
+ printf("%s was both %s and %s\n",
+ oid_to_hex(current_bad_oid),
+ term_good,
+ term_bad);
exit(1);
}
@@ -935,11 +974,11 @@ int bisect_next_all(const char *prefix, int no_checkout)
}
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 the first bad commit\n", bisect_rev_hex);
+ if (!hashcmp(bisect_rev, current_bad_oid->hash)) {
+ exit_if_skipped_commits(tried, current_bad_oid);
+ printf("%s is the first %s commit\n", sha1_to_hex(bisect_rev),
+ term_bad);
show_diff_tree(prefix, revs.commits->item);
/* This means the bisection process succeeded. */
exit(10);
@@ -951,6 +990,44 @@ int bisect_next_all(const char *prefix, int no_checkout)
"(roughly %d step%s)\n", nr, (nr == 1 ? "" : "s"),
steps, (steps == 1 ? "" : "s"));
- return bisect_checkout(bisect_rev_hex, no_checkout);
+ return bisect_checkout(bisect_rev, no_checkout);
}
+static inline int log2i(int n)
+{
+ int log2 = 0;
+
+ for (; n > 1; n >>= 1)
+ log2++;
+
+ return log2;
+}
+
+static inline int exp2i(int n)
+{
+ return 1 << n;
+}
+
+/*
+ * Estimate the number of bisect steps left (after the current step)
+ *
+ * For any x between 0 included and 2^n excluded, the probability for
+ * n - 1 steps left looks like:
+ *
+ * P(2^n + x) == (2^n - x) / (2^n + x)
+ *
+ * and P(2^n + x) < 0.5 means 2^n < 3x
+ */
+int estimate_bisect_steps(int all)
+{
+ int n, x, e;
+
+ if (all < 3)
+ return 0;
+
+ n = log2i(all);
+ e = exp2i(n);
+ x = all - e;
+
+ return (e < 3 * x) ? n : n - 1;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 20:03:34 +0000