bisect: use update_ref

Instead of manually writing a pseudoref (in one case) and shelling out
to git update-ref (in another), use the update_ref function.  This
is much simpler.

Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/bisect.c b/bisect.c
index 03d5cd9..7eaa37a 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -19,7 +19,6 @@ 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};
 
 /* Remember to update object flag allocation in object.h */
 #define COUNTED                (1u<<16)
@@ -666,34 +665,16 @@ static int is_expected_rev(const struct object_id *oid)
        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_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)
+static int bisect_checkout(const unsigned char *bisect_rev, int no_checkout)
 {
+       char bisect_rev_hex[GIT_SHA1_HEXSZ + 1];
 
-       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);
@@ -789,7 +770,7 @@ 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));
                }
        }
 
@@ -903,7 +884,6 @@ 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[GIT_SHA1_HEXSZ + 1];
 
        if (read_bisect_refs())
                die("reading bisect refs failed");
@@ -938,11 +918,10 @@ 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), GIT_SHA1_HEXSZ + 1);
 
        if (!hashcmp(bisect_rev, current_bad_oid->hash)) {
                exit_if_skipped_commits(tried, current_bad_oid);
-               printf("%s is the first bad commit\n", bisect_rev_hex);
+               printf("%s is the first bad commit\n", sha1_to_hex(bisect_rev));
                show_diff_tree(prefix, revs.commits->item);
                /* This means the bisection process succeeded. */
                exit(10);
@@ -954,7 +933,7 @@ 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)