core Git. Porcelains expose more of a <<def_SCM,SCM>>
interface than the <<def_plumbing,plumbing>>.
+[[def_per_worktree_ref]]per-worktree ref::
+ Refs that are per-<<def_working_tree,worktree>>, rather than
+ global. This is presently only <<def_HEAD,HEAD>>, but might
+ later include other unusual refs.
+
+[[def_pseudoref]]pseudoref::
+ Pseudorefs are a class of files under `$GIT_DIR` which behave
+ like refs for the purposes of rev-parse, but which are treated
+ specially by git. Pseudorefs both have names that are all-caps,
+ and always start with a line consisting of a
+ <<def_SHA1,SHA-1>> followed by whitespace. So, HEAD is not a
+ pseudoref, because it is sometimes a symbolic ref. They might
+ optionally contain some additional data. `MERGE_HEAD` and
+ `CHERRY_PICK_HEAD` are examples. Unlike
+ <<def_per_worktree_ref,per-worktree refs>>, these files cannot
+ be symbolic refs, and never have reflogs. They also cannot be
+ updated through the normal ref update machinery. Instead,
+ they are updated by directly writing to the files. However,
+ they can be read as if they were refs, so `git rev-parse
+ MERGE_HEAD` will work.
+
[[def_pull]]pull::
Pulling a <<def_branch,branch>> means to <<def_fetch,fetch>> it and
<<def_merge,merge>> it. See also linkgit:git-pull[1].
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};
static const char *term_bad;
static const char *term_good;
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);
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));
}
}
struct commit_list *tried;
int reaches = 0, all = 0, nr, steps;
const unsigned char *bisect_rev;
- char bisect_rev_hex[GIT_SHA1_HEXSZ + 1];
read_bisect_terms(&term_bad, &term_good);
if (read_bisect_refs())
}
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 %s commit\n", bisect_rev_hex,
+ 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. */
"(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)
return 0;
}
+static int is_per_worktree_ref(const char *refname)
+{
+ return !strcmp(refname, "HEAD");
+}
+
+static int is_pseudoref_syntax(const char *refname)
+{
+ const char *c;
+
+ for (c = refname; *c; c++) {
+ if (!isupper(*c) && *c != '-' && *c != '_')
+ return 0;
+ }
+
+ return 1;
+}
+
+enum ref_type ref_type(const char *refname)
+{
+ if (is_per_worktree_ref(refname))
+ return REF_TYPE_PER_WORKTREE;
+ if (is_pseudoref_syntax(refname))
+ return REF_TYPE_PSEUDOREF;
+ return REF_TYPE_NORMAL;
+}
+
+static int write_pseudoref(const char *pseudoref, const unsigned char *sha1,
+ const unsigned char *old_sha1, struct strbuf *err)
+{
+ const char *filename;
+ int fd;
+ static struct lock_file lock;
+ struct strbuf buf = STRBUF_INIT;
+ int ret = -1;
+
+ strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
+
+ filename = git_path("%s", pseudoref);
+ fd = hold_lock_file_for_update(&lock, filename, LOCK_DIE_ON_ERROR);
+ if (fd < 0) {
+ strbuf_addf(err, "Could not open '%s' for writing: %s",
+ filename, strerror(errno));
+ return -1;
+ }
+
+ if (old_sha1) {
+ unsigned char actual_old_sha1[20];
+
+ if (read_ref(pseudoref, actual_old_sha1))
+ die("could not read ref '%s'", pseudoref);
+ if (hashcmp(actual_old_sha1, old_sha1)) {
+ strbuf_addf(err, "Unexpected sha1 when writing %s", pseudoref);
+ rollback_lock_file(&lock);
+ goto done;
+ }
+ }
+
+ if (write_in_full(fd, buf.buf, buf.len) != buf.len) {
+ strbuf_addf(err, "Could not write to '%s'", filename);
+ rollback_lock_file(&lock);
+ goto done;
+ }
+
+ commit_lock_file(&lock);
+ ret = 0;
+done:
+ strbuf_release(&buf);
+ return ret;
+}
+
+static int delete_pseudoref(const char *pseudoref, const unsigned char *old_sha1)
+{
+ static struct lock_file lock;
+ const char *filename;
+
+ filename = git_path("%s", pseudoref);
+
+ if (old_sha1 && !is_null_sha1(old_sha1)) {
+ int fd;
+ unsigned char actual_old_sha1[20];
+
+ fd = hold_lock_file_for_update(&lock, filename,
+ LOCK_DIE_ON_ERROR);
+ if (fd < 0)
+ die_errno(_("Could not open '%s' for writing"), filename);
+ if (read_ref(pseudoref, actual_old_sha1))
+ die("could not read ref '%s'", pseudoref);
+ if (hashcmp(actual_old_sha1, old_sha1)) {
+ warning("Unexpected sha1 when deleting %s", pseudoref);
+ rollback_lock_file(&lock);
+ return -1;
+ }
+
+ unlink(filename);
+ rollback_lock_file(&lock);
+ } else {
+ unlink(filename);
+ }
+
+ return 0;
+}
+
int delete_ref(const char *refname, const unsigned char *old_sha1,
unsigned int flags)
{
struct ref_transaction *transaction;
struct strbuf err = STRBUF_INIT;
+ if (ref_type(refname) == REF_TYPE_PSEUDOREF)
+ return delete_pseudoref(refname, old_sha1);
+
transaction = ref_transaction_begin(&err);
if (!transaction ||
ref_transaction_delete(transaction, refname, old_sha1,
const unsigned char *new_sha1, const unsigned char *old_sha1,
unsigned int flags, enum action_on_err onerr)
{
- struct ref_transaction *t;
+ struct ref_transaction *t = NULL;
struct strbuf err = STRBUF_INIT;
+ int ret = 0;
- t = ref_transaction_begin(&err);
- if (!t ||
- ref_transaction_update(t, refname, new_sha1, old_sha1,
- flags, msg, &err) ||
- ref_transaction_commit(t, &err)) {
+ if (ref_type(refname) == REF_TYPE_PSEUDOREF) {
+ ret = write_pseudoref(refname, new_sha1, old_sha1, &err);
+ } else {
+ t = ref_transaction_begin(&err);
+ if (!t ||
+ ref_transaction_update(t, refname, new_sha1, old_sha1,
+ flags, msg, &err) ||
+ ref_transaction_commit(t, &err)) {
+ ret = 1;
+ ref_transaction_free(t);
+ }
+ }
+ if (ret) {
const char *str = "update_ref failed for ref '%s': %s";
- ref_transaction_free(t);
switch (onerr) {
case UPDATE_REFS_MSG_ON_ERR:
error(str, refname, err.buf);
return 1;
}
strbuf_release(&err);
- ref_transaction_free(t);
+ if (t)
+ ref_transaction_free(t);
return 0;
}
extern int ref_is_hidden(const char *);
+enum ref_type {
+ REF_TYPE_PER_WORKTREE,
+ REF_TYPE_PSEUDOREF,
+ REF_TYPE_NORMAL,
+};
+
+enum ref_type ref_type(const char *refname);
+
enum expire_reflog_flags {
EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
unuse_commit_buffer(commit, msg->message);
}
-static void write_cherry_pick_head(struct commit *commit, const char *pseudoref)
-{
- const char *filename;
- int fd;
- struct strbuf buf = STRBUF_INIT;
-
- strbuf_addf(&buf, "%s\n", sha1_to_hex(commit->object.sha1));
-
- filename = git_path("%s", pseudoref);
- fd = open(filename, O_WRONLY | O_CREAT, 0666);
- if (fd < 0)
- die_errno(_("Could not open '%s' for writing"), filename);
- if (write_in_full(fd, buf.buf, buf.len) != buf.len || close(fd))
- die_errno(_("Could not write to '%s'"), filename);
- strbuf_release(&buf);
-}
-
static void print_advice(int show_hint, struct replay_opts *opts)
{
char *msg = getenv("GIT_CHERRY_PICK_HELP");
* write it at all.
*/
if (opts->action == REPLAY_PICK && !opts->no_commit && (res == 0 || res == 1))
- write_cherry_pick_head(commit, "CHERRY_PICK_HEAD");
+ update_ref(NULL, "CHERRY_PICK_HEAD", commit->object.sha1, NULL,
+ REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
if (opts->action == REPLAY_REVERT && ((opts->no_commit && res == 0) || res == 1))
- write_cherry_pick_head(commit, "REVERT_HEAD");
+ update_ref(NULL, "REVERT_HEAD", commit->object.sha1, NULL,
+ REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
if (res) {
error(opts->action == REPLAY_REVERT