#include "dir.h"
#include "string-list.h"
+struct ref_lock {
+ char *ref_name;
+ char *orig_ref_name;
+ struct lock_file *lk;
+ unsigned char old_sha1[20];
+ int lock_fd;
+};
+
/*
* How to handle various characters in refnames:
* 0: An acceptable character for refs
};
/*
- * Used as a flag to ref_transaction_delete when a loose ref is being
+ * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken
+ * refs (i.e., because the reference is about to be deleted anyway).
+ */
+#define REF_DELETING 0x02
+
+/*
+ * Used as a flag in ref_update::flags when a loose ref is being
* pruned.
*/
-#define REF_ISPRUNING 0x0100
+#define REF_ISPRUNING 0x04
+
+/*
+ * Used as a flag in ref_update::flags when the reference should be
+ * updated to new_sha1.
+ */
+#define REF_HAVE_NEW 0x08
+
+/*
+ * Used as a flag in ref_update::flags when old_sha1 should be
+ * checked.
+ */
+#define REF_HAVE_OLD 0x10
+
+/*
+ * Used as a flag in ref_update::flags when the lockfile needs to be
+ * committed.
+ */
+#define REF_NEEDS_COMMIT 0x20
+
/*
* Try to read one refname component from the front of refname.
* Return the length of the component found, or -1 if the component is
* presence of an empty subdirectory does not block the creation of a
* similarly-named reference. (The fact that reference names with the
* same leading components can conflict *with each other* is a
- * separate issue that is regulated by is_refname_available().)
+ * separate issue that is regulated by verify_refname_available().)
*
* Please note that the name field contains the fully-qualified
* reference (or subdirectory) name. Space could be saved by only
}
}
-static int entry_matches(struct ref_entry *entry, const struct string_list *list)
-{
- return list && string_list_has_string(list, entry->name);
-}
-
struct nonmatching_ref_data {
const struct string_list *skip;
- struct ref_entry *found;
+ const char *conflicting_refname;
};
static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata)
{
struct nonmatching_ref_data *data = vdata;
- if (entry_matches(entry, data->skip))
+ if (data->skip && string_list_has_string(data->skip, entry->name))
return 0;
- data->found = entry;
+ data->conflicting_refname = entry->name;
return 1;
}
-static void report_refname_conflict(struct ref_entry *entry,
- const char *refname)
-{
- error("'%s' exists; cannot create '%s'", entry->name, refname);
-}
-
/*
- * Return true iff a reference named refname could be created without
- * conflicting with the name of an existing reference in dir. If
- * skip is non-NULL, ignore potential conflicts with refs in skip
- * (e.g., because they are scheduled for deletion in the same
- * operation).
+ * Return 0 if a reference named refname could be created without
+ * conflicting with the name of an existing reference in dir.
+ * Otherwise, return a negative value and write an explanation to err.
+ * If extras is non-NULL, it is a list of additional refnames with
+ * which refname is not allowed to conflict. If skip is non-NULL,
+ * ignore potential conflicts with refs in skip (e.g., because they
+ * are scheduled for deletion in the same operation). Behavior is
+ * undefined if the same name is listed in both extras and skip.
*
* Two reference names conflict if one of them exactly matches the
- * leading components of the other; e.g., "foo/bar" conflicts with
- * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
- * "foo/barbados".
+ * leading components of the other; e.g., "refs/foo/bar" conflicts
+ * with both "refs/foo" and with "refs/foo/bar/baz" but not with
+ * "refs/foo/bar" or "refs/foo/barbados".
*
- * skip must be sorted.
+ * extras and skip must be sorted.
*/
-static int is_refname_available(const char *refname,
- const struct string_list *skip,
- struct ref_dir *dir)
+static int verify_refname_available(const char *refname,
+ const struct string_list *extras,
+ const struct string_list *skip,
+ struct ref_dir *dir,
+ struct strbuf *err)
{
const char *slash;
- size_t len;
int pos;
- char *dirname;
+ struct strbuf dirname = STRBUF_INIT;
+ int ret = -1;
+
+ /*
+ * For the sake of comments in this function, suppose that
+ * refname is "refs/foo/bar".
+ */
+
+ assert(err);
+ strbuf_grow(&dirname, strlen(refname) + 1);
for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
+ /* Expand dirname to the new prefix, not including the trailing slash: */
+ strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
+
/*
- * We are still at a leading dir of the refname; we are
- * looking for a conflict with a leaf entry.
- *
- * If we find one, we still must make sure it is
- * not in "skip".
+ * We are still at a leading dir of the refname (e.g.,
+ * "refs/foo"; if there is a reference with that name,
+ * it is a conflict, *unless* it is in skip.
*/
- pos = search_ref_dir(dir, refname, slash - refname);
- if (pos >= 0) {
- struct ref_entry *entry = dir->entries[pos];
- if (entry_matches(entry, skip))
- return 1;
- report_refname_conflict(entry, refname);
- return 0;
+ if (dir) {
+ pos = search_ref_dir(dir, dirname.buf, dirname.len);
+ if (pos >= 0 &&
+ (!skip || !string_list_has_string(skip, dirname.buf))) {
+ /*
+ * We found a reference whose name is
+ * a proper prefix of refname; e.g.,
+ * "refs/foo", and is not in skip.
+ */
+ strbuf_addf(err, "'%s' exists; cannot create '%s'",
+ dirname.buf, refname);
+ goto cleanup;
+ }
}
+ if (extras && string_list_has_string(extras, dirname.buf) &&
+ (!skip || !string_list_has_string(skip, dirname.buf))) {
+ strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
+ refname, dirname.buf);
+ goto cleanup;
+ }
/*
* Otherwise, we can try to continue our search with
- * the next component; if we come up empty, we know
- * there is nothing under this whole prefix.
+ * the next component. So try to look up the
+ * directory, e.g., "refs/foo/". If we come up empty,
+ * we know there is nothing under this whole prefix,
+ * but even in that case we still have to continue the
+ * search for conflicts with extras.
*/
- pos = search_ref_dir(dir, refname, slash + 1 - refname);
- if (pos < 0)
- return 1;
-
- dir = get_ref_dir(dir->entries[pos]);
+ strbuf_addch(&dirname, '/');
+ if (dir) {
+ pos = search_ref_dir(dir, dirname.buf, dirname.len);
+ if (pos < 0) {
+ /*
+ * There was no directory "refs/foo/",
+ * so there is nothing under this
+ * whole prefix. So there is no need
+ * to continue looking for conflicting
+ * references. But we need to continue
+ * looking for conflicting extras.
+ */
+ dir = NULL;
+ } else {
+ dir = get_ref_dir(dir->entries[pos]);
+ }
+ }
}
/*
- * We are at the leaf of our refname; we want to
- * make sure there are no directories which match it.
+ * We are at the leaf of our refname (e.g., "refs/foo/bar").
+ * There is no point in searching for a reference with that
+ * name, because a refname isn't considered to conflict with
+ * itself. But we still need to check for references whose
+ * names are in the "refs/foo/bar/" namespace, because they
+ * *do* conflict.
*/
- len = strlen(refname);
- dirname = xmallocz(len + 1);
- sprintf(dirname, "%s/", refname);
- pos = search_ref_dir(dir, dirname, len + 1);
- free(dirname);
+ strbuf_addstr(&dirname, refname + dirname.len);
+ strbuf_addch(&dirname, '/');
- if (pos >= 0) {
+ if (dir) {
+ pos = search_ref_dir(dir, dirname.buf, dirname.len);
+
+ if (pos >= 0) {
+ /*
+ * We found a directory named "$refname/"
+ * (e.g., "refs/foo/bar/"). It is a problem
+ * iff it contains any ref that is not in
+ * "skip".
+ */
+ struct nonmatching_ref_data data;
+
+ data.skip = skip;
+ data.conflicting_refname = NULL;
+ dir = get_ref_dir(dir->entries[pos]);
+ sort_ref_dir(dir);
+ if (do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data)) {
+ strbuf_addf(err, "'%s' exists; cannot create '%s'",
+ data.conflicting_refname, refname);
+ goto cleanup;
+ }
+ }
+ }
+
+ if (extras) {
/*
- * We found a directory named "refname". It is a
- * problem iff it contains any ref that is not
- * in "skip".
+ * Check for entries in extras that start with
+ * "$refname/". We do that by looking for the place
+ * where "$refname/" would be inserted in extras. If
+ * there is an entry at that position that starts with
+ * "$refname/" and is not in skip, then we have a
+ * conflict.
*/
- struct ref_entry *entry = dir->entries[pos];
- struct ref_dir *dir = get_ref_dir(entry);
- struct nonmatching_ref_data data;
+ for (pos = string_list_find_insert_index(extras, dirname.buf, 0);
+ pos < extras->nr; pos++) {
+ const char *extra_refname = extras->items[pos].string;
- data.skip = skip;
- sort_ref_dir(dir);
- if (!do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data))
- return 1;
+ if (!starts_with(extra_refname, dirname.buf))
+ break;
- report_refname_conflict(data.found, refname);
- return 0;
+ if (!skip || !string_list_has_string(skip, extra_refname)) {
+ strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
+ refname, extra_refname);
+ goto cleanup;
+ }
+ }
}
- /*
- * There is no point in searching for another leaf
- * node which matches it; such an entry would be the
- * ref we are looking for, not a conflict.
- */
- return 1;
+ /* No conflicts were found */
+ ret = 0;
+
+cleanup:
+ strbuf_release(&dirname);
+ return ret;
}
struct packed_ref_cache {
char *resolve_refdup(const char *ref, int resolve_flags, unsigned char *sha1, int *flags)
{
- const char *ret = resolve_ref_unsafe(ref, resolve_flags, sha1, flags);
- return ret ? xstrdup(ret) : NULL;
+ return xstrdup_or_null(resolve_ref_unsafe(ref, resolve_flags, sha1, flags));
}
/* The argument to filter_refs */
data.fn = fn;
data.cb_data = cb_data;
+ if (ref_paranoia < 0)
+ ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
+ if (ref_paranoia)
+ data.flags |= DO_FOR_EACH_INCLUDE_BROKEN;
+
return do_for_each_entry(refs, base, do_one_ref, &data);
}
return 0;
}
+static void unlock_ref(struct ref_lock *lock)
+{
+ /* Do not free lock->lk -- atexit() still looks at them */
+ if (lock->lk)
+ rollback_lock_file(lock->lk);
+ free(lock->ref_name);
+ free(lock->orig_ref_name);
+ free(lock);
+}
+
/* This function should make sure errno is meaningful on error */
static struct ref_lock *verify_lock(struct ref_lock *lock,
const unsigned char *old_sha1, int mustexist)
*/
static struct ref_lock *lock_ref_sha1_basic(const char *refname,
const unsigned char *old_sha1,
+ const struct string_list *extras,
const struct string_list *skip,
- int flags, int *type_p)
+ unsigned int flags, int *type_p,
+ struct strbuf *err)
{
char *ref_file;
const char *orig_refname = refname;
int type, lflags;
int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
int resolve_flags = 0;
- int missing = 0;
int attempts_remaining = 3;
+ assert(err);
+
lock = xcalloc(1, sizeof(struct ref_lock));
lock->lock_fd = -1;
ref_file = git_path("%s", orig_refname);
if (remove_empty_directories(ref_file)) {
last_errno = errno;
- error("there are still refs under '%s'", orig_refname);
+
+ if (!verify_refname_available(orig_refname, extras, skip,
+ get_loose_refs(&ref_cache), err))
+ strbuf_addf(err, "there are still refs under '%s'",
+ orig_refname);
+
goto error_return;
}
refname = resolve_ref_unsafe(orig_refname, resolve_flags,
*type_p = type;
if (!refname) {
last_errno = errno;
- error("unable to resolve reference %s: %s",
- orig_refname, strerror(errno));
+ if (last_errno != ENOTDIR ||
+ !verify_refname_available(orig_refname, extras, skip,
+ get_loose_refs(&ref_cache), err))
+ strbuf_addf(err, "unable to resolve reference %s: %s",
+ orig_refname, strerror(last_errno));
+
goto error_return;
}
- missing = is_null_sha1(lock->old_sha1);
- /* When the ref did not exist and we are creating it,
- * make sure there is no existing ref that is packed
- * whose name begins with our refname, nor a ref whose
- * name is a proper prefix of our refname.
+ /*
+ * If the ref did not exist and we are creating it, make sure
+ * there is no existing packed ref whose name begins with our
+ * refname, nor a packed ref whose name is a proper prefix of
+ * our refname.
*/
- if (missing &&
- !is_refname_available(refname, skip, get_packed_refs(&ref_cache))) {
+ if (is_null_sha1(lock->old_sha1) &&
+ verify_refname_available(refname, extras, skip,
+ get_packed_refs(&ref_cache), err)) {
last_errno = ENOTDIR;
goto error_return;
}
lock->ref_name = xstrdup(refname);
lock->orig_ref_name = xstrdup(orig_refname);
ref_file = git_path("%s", refname);
- if (missing)
- lock->force_write = 1;
- if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
- lock->force_write = 1;
retry:
switch (safe_create_leading_directories(ref_file)) {
/* fall through */
default:
last_errno = errno;
- error("unable to create directory for %s", ref_file);
+ strbuf_addf(err, "unable to create directory for %s", ref_file);
goto error_return;
}
lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
if (lock->lock_fd < 0) {
+ last_errno = errno;
if (errno == ENOENT && --attempts_remaining > 0)
/*
* Maybe somebody just deleted one of the
* again:
*/
goto retry;
- else
- unable_to_lock_die(ref_file, errno);
+ else {
+ unable_to_lock_message(ref_file, errno, err);
+ goto error_return;
+ }
}
return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
return NULL;
}
-struct ref_lock *lock_any_ref_for_update(const char *refname,
- const unsigned char *old_sha1,
- int flags, int *type_p)
-{
- return lock_ref_sha1_basic(refname, old_sha1, NULL, flags, type_p);
-}
-
/*
* Write an entry to the packed-refs file for the specified refname.
* If peeled is non-NULL, write it as the entry's peeled value.
transaction = ref_transaction_begin(&err);
if (!transaction ||
ref_transaction_delete(transaction, r->name, r->sha1,
- REF_ISPRUNING, 1, NULL, &err) ||
+ REF_ISPRUNING, NULL, &err) ||
ref_transaction_commit(transaction, &err)) {
ref_transaction_free(transaction);
error("%s", err.buf);
return 0;
}
-/*
- * If entry is no longer needed in packed-refs, add it to the string
- * list pointed to by cb_data. Reasons for deleting entries:
- *
- * - Entry is broken.
- * - Entry is overridden by a loose ref.
- * - Entry does not point at a valid object.
- *
- * In the first and third cases, also emit an error message because these
- * are indications of repository corruption.
- */
-static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
-{
- struct string_list *refs_to_delete = cb_data;
-
- if (entry->flag & REF_ISBROKEN) {
- /* This shouldn't happen to packed refs. */
- error("%s is broken!", entry->name);
- string_list_append(refs_to_delete, entry->name);
- return 0;
- }
- if (!has_sha1_file(entry->u.value.sha1)) {
- unsigned char sha1[20];
- int flags;
-
- if (read_ref_full(entry->name, 0, sha1, &flags))
- /* We should at least have found the packed ref. */
- die("Internal error");
- if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
- /*
- * This packed reference is overridden by a
- * loose reference, so it is OK that its value
- * is no longer valid; for example, it might
- * refer to an object that has been garbage
- * collected. For this purpose we don't even
- * care whether the loose reference itself is
- * invalid, broken, symbolic, etc. Silently
- * remove the packed reference.
- */
- string_list_append(refs_to_delete, entry->name);
- return 0;
- }
- /*
- * There is no overriding loose reference, so the fact
- * that this reference doesn't refer to a valid object
- * indicates some kind of repository corruption.
- * Report the problem, then omit the reference from
- * the output.
- */
- error("%s does not point to a valid object!", entry->name);
- string_list_append(refs_to_delete, entry->name);
- return 0;
- }
-
- return 0;
-}
-
-int repack_without_refs(const char **refnames, int n, struct strbuf *err)
+int repack_without_refs(struct string_list *refnames, struct strbuf *err)
{
struct ref_dir *packed;
- struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
- struct string_list_item *ref_to_delete;
- int i, ret, removed = 0;
+ struct string_list_item *refname;
+ int ret, needs_repacking = 0, removed = 0;
assert(err);
/* Look for a packed ref */
- for (i = 0; i < n; i++)
- if (get_packed_ref(refnames[i]))
+ for_each_string_list_item(refname, refnames) {
+ if (get_packed_ref(refname->string)) {
+ needs_repacking = 1;
break;
+ }
+ }
/* Avoid locking if we have nothing to do */
- if (i == n)
+ if (!needs_repacking)
return 0; /* no refname exists in packed refs */
if (lock_packed_refs(0)) {
packed = get_packed_refs(&ref_cache);
/* Remove refnames from the cache */
- for (i = 0; i < n; i++)
- if (remove_entry(packed, refnames[i]) != -1)
+ for_each_string_list_item(refname, refnames)
+ if (remove_entry(packed, refname->string) != -1)
removed = 1;
if (!removed) {
/*
return 0;
}
- /* Remove any other accumulated cruft */
- do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);
- for_each_string_list_item(ref_to_delete, &refs_to_delete) {
- if (remove_entry(packed, ref_to_delete->string) == -1)
- die("internal error");
- }
-
/* Write what remains */
ret = commit_packed_refs();
if (ret)
return 0;
}
-int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
+int delete_ref(const char *refname, const unsigned char *sha1, unsigned int flags)
{
struct ref_transaction *transaction;
struct strbuf err = STRBUF_INIT;
transaction = ref_transaction_begin(&err);
if (!transaction ||
- ref_transaction_delete(transaction, refname, sha1, delopt,
- sha1 && !is_null_sha1(sha1), NULL, &err) ||
+ ref_transaction_delete(transaction, refname,
+ (sha1 && !is_null_sha1(sha1)) ? sha1 : NULL,
+ flags, NULL, &err) ||
ref_transaction_commit(transaction, &err)) {
error("%s", err.buf);
ref_transaction_free(transaction);
static int rename_ref_available(const char *oldname, const char *newname)
{
struct string_list skip = STRING_LIST_INIT_NODUP;
+ struct strbuf err = STRBUF_INIT;
int ret;
string_list_insert(&skip, oldname);
- ret = is_refname_available(newname, &skip, get_packed_refs(&ref_cache))
- && is_refname_available(newname, &skip, get_loose_refs(&ref_cache));
+ ret = !verify_refname_available(newname, NULL, &skip,
+ get_packed_refs(&ref_cache), &err)
+ && !verify_refname_available(newname, NULL, &skip,
+ get_loose_refs(&ref_cache), &err);
+ if (!ret)
+ error("%s", err.buf);
+
string_list_clear(&skip, 0);
+ strbuf_release(&err);
return ret;
}
struct stat loginfo;
int log = !lstat(git_path("logs/%s", oldrefname), &loginfo);
const char *symref = NULL;
+ struct strbuf err = STRBUF_INIT;
if (log && S_ISLNK(loginfo.st_mode))
return error("reflog for %s is a symlink", oldrefname);
logmoved = log;
- lock = lock_ref_sha1_basic(newrefname, NULL, NULL, 0, NULL);
+ lock = lock_ref_sha1_basic(newrefname, NULL, NULL, NULL, 0, NULL, &err);
if (!lock) {
- error("unable to lock %s for update", newrefname);
+ error("unable to rename '%s' to '%s': %s", oldrefname, newrefname, err.buf);
+ strbuf_release(&err);
goto rollback;
}
- lock->force_write = 1;
hashcpy(lock->old_sha1, orig_sha1);
if (write_ref_to_lockfile(lock, orig_sha1) ||
return 0;
rollback:
- lock = lock_ref_sha1_basic(oldrefname, NULL, NULL, 0, NULL);
+ lock = lock_ref_sha1_basic(oldrefname, NULL, NULL, NULL, 0, NULL, &err);
if (!lock) {
- error("unable to lock %s for rollback", oldrefname);
+ error("unable to lock %s for rollback: %s", oldrefname, err.buf);
+ strbuf_release(&err);
goto rollbacklog;
}
- lock->force_write = 1;
flag = log_all_ref_updates;
log_all_ref_updates = 0;
if (write_ref_to_lockfile(lock, orig_sha1) ||
return 1;
}
-int close_ref(struct ref_lock *lock)
+static int close_ref(struct ref_lock *lock)
{
if (close_lock_file(lock->lk))
return -1;
return 0;
}
-int commit_ref(struct ref_lock *lock)
+static int commit_ref(struct ref_lock *lock)
{
if (commit_lock_file(lock->lk))
return -1;
return 0;
}
-void unlock_ref(struct ref_lock *lock)
-{
- /* Do not free lock->lk -- atexit() still looks at them */
- if (lock->lk)
- rollback_lock_file(lock->lk);
- free(lock->ref_name);
- free(lock->orig_ref_name);
- free(lock);
-}
-
/*
* copy the reflog message msg to buf, which has been allocated sufficiently
* large, while cleaning up the whitespaces. Especially, convert LF to space,
return 0;
}
+static int log_ref_write_fd(int fd, const unsigned char *old_sha1,
+ const unsigned char *new_sha1,
+ const char *committer, const char *msg)
+{
+ int msglen, written;
+ unsigned maxlen, len;
+ char *logrec;
+
+ msglen = msg ? strlen(msg) : 0;
+ maxlen = strlen(committer) + msglen + 100;
+ logrec = xmalloc(maxlen);
+ len = sprintf(logrec, "%s %s %s\n",
+ sha1_to_hex(old_sha1),
+ sha1_to_hex(new_sha1),
+ committer);
+ if (msglen)
+ len += copy_msg(logrec + len - 1, msg) - 1;
+
+ written = len <= maxlen ? write_in_full(fd, logrec, len) : -1;
+ free(logrec);
+ if (written != len)
+ return -1;
+
+ return 0;
+}
+
static int log_ref_write(const char *refname, const unsigned char *old_sha1,
const unsigned char *new_sha1, const char *msg)
{
- int logfd, result, written, oflags = O_APPEND | O_WRONLY;
- unsigned maxlen, len;
- int msglen;
+ int logfd, result, oflags = O_APPEND | O_WRONLY;
char log_file[PATH_MAX];
- char *logrec;
- const char *committer;
if (log_all_ref_updates < 0)
log_all_ref_updates = !is_bare_repository();
logfd = open(log_file, oflags);
if (logfd < 0)
return 0;
- msglen = msg ? strlen(msg) : 0;
- committer = git_committer_info(0);
- maxlen = strlen(committer) + msglen + 100;
- logrec = xmalloc(maxlen);
- len = sprintf(logrec, "%s %s %s\n",
- sha1_to_hex(old_sha1),
- sha1_to_hex(new_sha1),
- committer);
- if (msglen)
- len += copy_msg(logrec + len - 1, msg) - 1;
- written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
- free(logrec);
- if (written != len) {
+ result = log_ref_write_fd(logfd, old_sha1, new_sha1,
+ git_committer_info(0), msg);
+ if (result) {
int save_errno = errno;
close(logfd);
error("Unable to append to %s", log_file);
}
/**
- * Information needed for a single ref update. Set new_sha1 to the
- * new value or to zero to delete the ref. To check the old value
- * while locking the ref, set have_old to 1 and set old_sha1 to the
- * value or to zero to ensure the ref does not exist before update.
+ * Information needed for a single ref update. Set new_sha1 to the new
+ * value or to null_sha1 to delete the ref. To check the old value
+ * while the ref is locked, set (flags & REF_HAVE_OLD) and set
+ * old_sha1 to the old value, or to null_sha1 to ensure the ref does
+ * not exist before update.
*/
struct ref_update {
+ /*
+ * If (flags & REF_HAVE_NEW), set the reference to this value:
+ */
unsigned char new_sha1[20];
+ /*
+ * If (flags & REF_HAVE_OLD), check that the reference
+ * previously had this value:
+ */
unsigned char old_sha1[20];
- int flags; /* REF_NODEREF? */
- int have_old; /* 1 if old_sha1 is valid, 0 otherwise */
+ /*
+ * One or more of REF_HAVE_NEW, REF_HAVE_OLD, REF_NODEREF,
+ * REF_DELETING, and REF_ISPRUNING:
+ */
+ unsigned int flags;
struct ref_lock *lock;
int type;
char *msg;
const char *refname,
const unsigned char *new_sha1,
const unsigned char *old_sha1,
- int flags, int have_old, const char *msg,
+ unsigned int flags, const char *msg,
struct strbuf *err)
{
struct ref_update *update;
if (transaction->state != REF_TRANSACTION_OPEN)
die("BUG: update called for transaction that is not open");
- if (have_old && !old_sha1)
- die("BUG: have_old is true but old_sha1 is NULL");
-
- if (!is_null_sha1(new_sha1) &&
+ if (new_sha1 && !is_null_sha1(new_sha1) &&
check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
strbuf_addf(err, "refusing to update ref with bad name %s",
refname);
}
update = add_update(transaction, refname);
- hashcpy(update->new_sha1, new_sha1);
- update->flags = flags;
- update->have_old = have_old;
- if (have_old)
+ if (new_sha1) {
+ hashcpy(update->new_sha1, new_sha1);
+ flags |= REF_HAVE_NEW;
+ }
+ if (old_sha1) {
hashcpy(update->old_sha1, old_sha1);
+ flags |= REF_HAVE_OLD;
+ }
+ update->flags = flags;
if (msg)
update->msg = xstrdup(msg);
return 0;
int ref_transaction_create(struct ref_transaction *transaction,
const char *refname,
const unsigned char *new_sha1,
- int flags, const char *msg,
+ unsigned int flags, const char *msg,
struct strbuf *err)
{
- struct ref_update *update;
-
- assert(err);
-
- if (transaction->state != REF_TRANSACTION_OPEN)
- die("BUG: create called for transaction that is not open");
-
if (!new_sha1 || is_null_sha1(new_sha1))
- die("BUG: create ref with null new_sha1");
-
- if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
- strbuf_addf(err, "refusing to create ref with bad name %s",
- refname);
- return -1;
- }
-
- update = add_update(transaction, refname);
-
- hashcpy(update->new_sha1, new_sha1);
- hashclr(update->old_sha1);
- update->flags = flags;
- update->have_old = 1;
- if (msg)
- update->msg = xstrdup(msg);
- return 0;
+ die("BUG: create called without valid new_sha1");
+ return ref_transaction_update(transaction, refname, new_sha1,
+ null_sha1, flags, msg, err);
}
int ref_transaction_delete(struct ref_transaction *transaction,
const char *refname,
const unsigned char *old_sha1,
- int flags, int have_old, const char *msg,
+ unsigned int flags, const char *msg,
struct strbuf *err)
{
- struct ref_update *update;
-
- assert(err);
-
- if (transaction->state != REF_TRANSACTION_OPEN)
- die("BUG: delete called for transaction that is not open");
-
- if (have_old && !old_sha1)
- die("BUG: have_old is true but old_sha1 is NULL");
+ if (old_sha1 && is_null_sha1(old_sha1))
+ die("BUG: delete called with old_sha1 set to zeros");
+ return ref_transaction_update(transaction, refname,
+ null_sha1, old_sha1,
+ flags, msg, err);
+}
- update = add_update(transaction, refname);
- update->flags = flags;
- update->have_old = have_old;
- if (have_old) {
- assert(!is_null_sha1(old_sha1));
- hashcpy(update->old_sha1, old_sha1);
- }
- if (msg)
- update->msg = xstrdup(msg);
- return 0;
+int ref_transaction_verify(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *old_sha1,
+ unsigned int flags,
+ struct strbuf *err)
+{
+ if (!old_sha1)
+ die("BUG: verify called with old_sha1 set to NULL");
+ return ref_transaction_update(transaction, refname,
+ NULL, old_sha1,
+ flags, NULL, err);
}
-int update_ref(const char *action, const char *refname,
- const unsigned char *sha1, const unsigned char *oldval,
- int flags, enum action_on_err onerr)
+int update_ref(const char *msg, const char *refname,
+ const unsigned char *new_sha1, const unsigned char *old_sha1,
+ unsigned int flags, enum action_on_err onerr)
{
struct ref_transaction *t;
struct strbuf err = STRBUF_INIT;
t = ref_transaction_begin(&err);
if (!t ||
- ref_transaction_update(t, refname, sha1, oldval, flags,
- !!oldval, action, &err) ||
+ ref_transaction_update(t, refname, new_sha1, old_sha1,
+ flags, msg, &err) ||
ref_transaction_commit(t, &err)) {
const char *str = "update_ref failed for ref '%s': %s";
return 0;
}
-static int ref_update_compare(const void *r1, const void *r2)
-{
- const struct ref_update * const *u1 = r1;
- const struct ref_update * const *u2 = r2;
- return strcmp((*u1)->refname, (*u2)->refname);
-}
-
-static int ref_update_reject_duplicates(struct ref_update **updates, int n,
+static int ref_update_reject_duplicates(struct string_list *refnames,
struct strbuf *err)
{
- int i;
+ int i, n = refnames->nr;
assert(err);
for (i = 1; i < n; i++)
- if (!strcmp(updates[i - 1]->refname, updates[i]->refname)) {
+ if (!strcmp(refnames->items[i - 1].string, refnames->items[i].string)) {
strbuf_addf(err,
"Multiple updates for ref '%s' not allowed.",
- updates[i]->refname);
+ refnames->items[i].string);
return 1;
}
return 0;
int ref_transaction_commit(struct ref_transaction *transaction,
struct strbuf *err)
{
- int ret = 0, delnum = 0, i;
- const char **delnames;
+ int ret = 0, i;
int n = transaction->nr;
struct ref_update **updates = transaction->updates;
+ struct string_list refs_to_delete = STRING_LIST_INIT_NODUP;
+ struct string_list_item *ref_to_delete;
+ struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
assert(err);
return 0;
}
- /* Allocate work space */
- delnames = xmalloc(sizeof(*delnames) * n);
-
- /* Copy, sort, and reject duplicate refs */
- qsort(updates, n, sizeof(*updates), ref_update_compare);
- if (ref_update_reject_duplicates(updates, n, err)) {
+ /* Fail if a refname appears more than once in the transaction: */
+ for (i = 0; i < n; i++)
+ string_list_append(&affected_refnames, updates[i]->refname);
+ string_list_sort(&affected_refnames);
+ if (ref_update_reject_duplicates(&affected_refnames, err)) {
ret = TRANSACTION_GENERIC_ERROR;
goto cleanup;
}
- /* Acquire all locks while verifying old values */
+ /*
+ * Acquire all locks, verify old values if provided, check
+ * that new values are valid, and write new values to the
+ * lockfiles, ready to be activated. Only keep one lockfile
+ * open at a time to avoid running out of file descriptors.
+ */
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
- if (is_null_sha1(update->new_sha1))
+ if ((update->flags & REF_HAVE_NEW) &&
+ is_null_sha1(update->new_sha1))
update->flags |= REF_DELETING;
- update->lock = lock_ref_sha1_basic(update->refname,
- (update->have_old ?
- update->old_sha1 :
- NULL),
- NULL,
- update->flags,
- &update->type);
+ update->lock = lock_ref_sha1_basic(
+ update->refname,
+ ((update->flags & REF_HAVE_OLD) ?
+ update->old_sha1 : NULL),
+ &affected_refnames, NULL,
+ update->flags,
+ &update->type,
+ err);
if (!update->lock) {
+ char *reason;
+
ret = (errno == ENOTDIR)
? TRANSACTION_NAME_CONFLICT
: TRANSACTION_GENERIC_ERROR;
- strbuf_addf(err, "Cannot lock the ref '%s'.",
- update->refname);
+ reason = strbuf_detach(err, NULL);
+ strbuf_addf(err, "Cannot lock ref '%s': %s",
+ update->refname, reason);
+ free(reason);
goto cleanup;
}
+ if ((update->flags & REF_HAVE_NEW) &&
+ !(update->flags & REF_DELETING)) {
+ int overwriting_symref = ((update->type & REF_ISSYMREF) &&
+ (update->flags & REF_NODEREF));
+
+ if (!overwriting_symref &&
+ !hashcmp(update->lock->old_sha1, update->new_sha1)) {
+ /*
+ * The reference already has the desired
+ * value, so we don't need to write it.
+ */
+ } else if (write_ref_to_lockfile(update->lock,
+ update->new_sha1)) {
+ /*
+ * The lock was freed upon failure of
+ * write_ref_to_lockfile():
+ */
+ update->lock = NULL;
+ strbuf_addf(err, "Cannot update the ref '%s'.",
+ update->refname);
+ ret = TRANSACTION_GENERIC_ERROR;
+ goto cleanup;
+ } else {
+ update->flags |= REF_NEEDS_COMMIT;
+ }
+ }
+ if (!(update->flags & REF_NEEDS_COMMIT)) {
+ /*
+ * We didn't have to write anything to the lockfile.
+ * Close it to free up the file descriptor:
+ */
+ if (close_ref(update->lock)) {
+ strbuf_addf(err, "Couldn't close %s.lock",
+ update->refname);
+ goto cleanup;
+ }
+ }
}
/* Perform updates first so live commits remain referenced */
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
- if (!(update->flags & REF_DELETING)) {
- if (!update->lock->force_write &&
- !hashcmp(update->lock->old_sha1, update->new_sha1)) {
- unlock_ref(update->lock);
+ if (update->flags & REF_NEEDS_COMMIT) {
+ if (commit_ref_update(update->lock,
+ update->new_sha1, update->msg)) {
+ /* freed by commit_ref_update(): */
update->lock = NULL;
- } else if (write_ref_to_lockfile(update->lock, update->new_sha1) ||
- commit_ref_update(update->lock, update->new_sha1, update->msg)) {
- update->lock = NULL; /* freed by the above calls */
strbuf_addf(err, "Cannot update the ref '%s'.",
update->refname);
ret = TRANSACTION_GENERIC_ERROR;
goto cleanup;
} else {
- /* freed by the above calls: */
+ /* freed by commit_ref_update(): */
update->lock = NULL;
}
}
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
- if (update->lock) {
+ if (update->flags & REF_DELETING) {
if (delete_ref_loose(update->lock, update->type, err)) {
ret = TRANSACTION_GENERIC_ERROR;
goto cleanup;
}
if (!(update->flags & REF_ISPRUNING))
- delnames[delnum++] = update->lock->ref_name;
+ string_list_append(&refs_to_delete,
+ update->lock->ref_name);
}
}
- if (repack_without_refs(delnames, delnum, err)) {
+ if (repack_without_refs(&refs_to_delete, err)) {
ret = TRANSACTION_GENERIC_ERROR;
goto cleanup;
}
- for (i = 0; i < delnum; i++)
- unlink_or_warn(git_path("logs/%s", delnames[i]));
+ for_each_string_list_item(ref_to_delete, &refs_to_delete)
+ unlink_or_warn(git_path("logs/%s", ref_to_delete->string));
clear_loose_ref_cache(&ref_cache);
cleanup:
for (i = 0; i < n; i++)
if (updates[i]->lock)
unlock_ref(updates[i]->lock);
- free(delnames);
+ string_list_clear(&refs_to_delete, 0);
+ string_list_clear(&affected_refnames, 0);
return ret;
}
}
return 0;
}
+
+struct expire_reflog_cb {
+ unsigned int flags;
+ reflog_expiry_should_prune_fn *should_prune_fn;
+ void *policy_cb;
+ FILE *newlog;
+ unsigned char last_kept_sha1[20];
+};
+
+static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
+ const char *email, unsigned long timestamp, int tz,
+ const char *message, void *cb_data)
+{
+ struct expire_reflog_cb *cb = cb_data;
+ struct expire_reflog_policy_cb *policy_cb = cb->policy_cb;
+
+ if (cb->flags & EXPIRE_REFLOGS_REWRITE)
+ osha1 = cb->last_kept_sha1;
+
+ if ((*cb->should_prune_fn)(osha1, nsha1, email, timestamp, tz,
+ message, policy_cb)) {
+ if (!cb->newlog)
+ printf("would prune %s", message);
+ else if (cb->flags & EXPIRE_REFLOGS_VERBOSE)
+ printf("prune %s", message);
+ } else {
+ if (cb->newlog) {
+ fprintf(cb->newlog, "%s %s %s %lu %+05d\t%s",
+ sha1_to_hex(osha1), sha1_to_hex(nsha1),
+ email, timestamp, tz, message);
+ hashcpy(cb->last_kept_sha1, nsha1);
+ }
+ if (cb->flags & EXPIRE_REFLOGS_VERBOSE)
+ printf("keep %s", message);
+ }
+ return 0;
+}
+
+int reflog_expire(const char *refname, const unsigned char *sha1,
+ unsigned int flags,
+ reflog_expiry_prepare_fn prepare_fn,
+ reflog_expiry_should_prune_fn should_prune_fn,
+ reflog_expiry_cleanup_fn cleanup_fn,
+ void *policy_cb_data)
+{
+ static struct lock_file reflog_lock;
+ struct expire_reflog_cb cb;
+ struct ref_lock *lock;
+ char *log_file;
+ int status = 0;
+ int type;
+ struct strbuf err = STRBUF_INIT;
+
+ memset(&cb, 0, sizeof(cb));
+ cb.flags = flags;
+ cb.policy_cb = policy_cb_data;
+ cb.should_prune_fn = should_prune_fn;
+
+ /*
+ * The reflog file is locked by holding the lock on the
+ * reference itself, plus we might need to update the
+ * reference if --updateref was specified:
+ */
+ lock = lock_ref_sha1_basic(refname, sha1, NULL, NULL, 0, &type, &err);
+ if (!lock) {
+ error("cannot lock ref '%s': %s", refname, err.buf);
+ strbuf_release(&err);
+ return -1;
+ }
+ if (!reflog_exists(refname)) {
+ unlock_ref(lock);
+ return 0;
+ }
+
+ log_file = git_pathdup("logs/%s", refname);
+ if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
+ /*
+ * Even though holding $GIT_DIR/logs/$reflog.lock has
+ * no locking implications, we use the lock_file
+ * machinery here anyway because it does a lot of the
+ * work we need, including cleaning up if the program
+ * exits unexpectedly.
+ */
+ if (hold_lock_file_for_update(&reflog_lock, log_file, 0) < 0) {
+ struct strbuf err = STRBUF_INIT;
+ unable_to_lock_message(log_file, errno, &err);
+ error("%s", err.buf);
+ strbuf_release(&err);
+ goto failure;
+ }
+ cb.newlog = fdopen_lock_file(&reflog_lock, "w");
+ if (!cb.newlog) {
+ error("cannot fdopen %s (%s)",
+ reflog_lock.filename.buf, strerror(errno));
+ goto failure;
+ }
+ }
+
+ (*prepare_fn)(refname, sha1, cb.policy_cb);
+ for_each_reflog_ent(refname, expire_reflog_ent, &cb);
+ (*cleanup_fn)(cb.policy_cb);
+
+ if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
+ /*
+ * It doesn't make sense to adjust a reference pointed
+ * to by a symbolic ref based on expiring entries in
+ * the symbolic reference's reflog. Nor can we update
+ * a reference if there are no remaining reflog
+ * entries.
+ */
+ int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) &&
+ !(type & REF_ISSYMREF) &&
+ !is_null_sha1(cb.last_kept_sha1);
+
+ if (close_lock_file(&reflog_lock)) {
+ status |= error("couldn't write %s: %s", log_file,
+ strerror(errno));
+ } else if (update &&
+ (write_in_full(lock->lock_fd,
+ sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
+ write_str_in_full(lock->lock_fd, "\n") != 1 ||
+ close_ref(lock) < 0)) {
+ status |= error("couldn't write %s",
+ lock->lk->filename.buf);
+ rollback_lock_file(&reflog_lock);
+ } else if (commit_lock_file(&reflog_lock)) {
+ status |= error("unable to commit reflog '%s' (%s)",
+ log_file, strerror(errno));
+ } else if (update && commit_ref(lock)) {
+ status |= error("couldn't set %s", lock->ref_name);
+ }
+ }
+ free(log_file);
+ unlock_ref(lock);
+ return status;
+
+ failure:
+ rollback_lock_file(&reflog_lock);
+ free(log_file);
+ unlock_ref(lock);
+ return -1;
+}