#include "string-list.h"
/*
- * Make sure "ref" is something reasonable to have under ".git/refs/";
- * We do not like it if:
+ * How to handle various characters in refnames:
+ * 0: An acceptable character for refs
+ * 1: End-of-component
+ * 2: ., look for a preceding . to reject .. in refs
+ * 3: {, look for a preceding @ to reject @{ in refs
+ * 4: A bad character: ASCII control characters, "~", "^", ":" or SP
+ */
+static unsigned char refname_disposition[256] = {
+ 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 2, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 0, 4, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
+};
+
+/*
+ * Used as a flag to ref_transaction_delete when a loose ref is being
+ * pruned.
+ */
+#define REF_ISPRUNING 0x0100
+/*
+ * Try to read one refname component from the front of refname.
+ * Return the length of the component found, or -1 if the component is
+ * not legal. It is legal if it is something reasonable to have under
+ * ".git/refs/"; We do not like it if:
*
* - any path component of it begins with ".", or
* - it has double dots "..", or
* - it ends with ".lock"
* - it contains a "\" (backslash)
*/
-
-/* Return true iff ch is not allowed in reference names. */
-static inline int bad_ref_char(int ch)
-{
- if (((unsigned) ch) <= ' ' || ch == 0x7f ||
- ch == '~' || ch == '^' || ch == ':' || ch == '\\')
- return 1;
- /* 2.13 Pattern Matching Notation */
- if (ch == '*' || ch == '?' || ch == '[') /* Unsupported */
- return 1;
- return 0;
-}
-
-/*
- * Try to read one refname component from the front of refname. Return
- * the length of the component found, or -1 if the component is not
- * legal.
- */
static int check_refname_component(const char *refname, int flags)
{
const char *cp;
char last = '\0';
for (cp = refname; ; cp++) {
- char ch = *cp;
- if (ch == '\0' || ch == '/')
+ int ch = *cp & 255;
+ unsigned char disp = refname_disposition[ch];
+ switch (disp) {
+ case 1:
+ goto out;
+ case 2:
+ if (last == '.')
+ return -1; /* Refname contains "..". */
break;
- if (bad_ref_char(ch))
- return -1; /* Illegal character in refname. */
- if (last == '.' && ch == '.')
- return -1; /* Refname contains "..". */
- if (last == '@' && ch == '{')
- return -1; /* Refname contains "@{". */
+ case 3:
+ if (last == '@')
+ return -1; /* Refname contains "@{". */
+ break;
+ case 4:
+ return -1;
+ }
last = ch;
}
+out:
if (cp == refname)
return 0; /* Component has zero length. */
if (refname[0] == '.') {
if (de->d_name[0] == '.')
continue;
- if (has_extension(de->d_name, ".lock"))
+ if (ends_with(de->d_name, ".lock"))
continue;
strbuf_addstr(&refname, de->d_name);
refdir = *refs->name
}
}
+/* This function needs to return a meaningful errno on failure */
const char *resolve_ref_unsafe(const char *refname, unsigned char *sha1, int reading, int *flag)
{
int depth = MAXDEPTH;
if (flag)
*flag = 0;
- if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL))
+ if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
+ errno = EINVAL;
return NULL;
+ }
for (;;) {
char path[PATH_MAX];
char *buf;
int fd;
- if (--depth < 0)
+ if (--depth < 0) {
+ errno = ELOOP;
return NULL;
+ }
git_snpath(path, sizeof(path), "%s", refname);
return NULL;
}
len = read_in_full(fd, buffer, sizeof(buffer)-1);
- close(fd);
- if (len < 0)
+ if (len < 0) {
+ int save_errno = errno;
+ close(fd);
+ errno = save_errno;
return NULL;
+ }
+ close(fd);
while (len && isspace(buffer[len-1]))
len--;
buffer[len] = '\0';
(buffer[40] != '\0' && !isspace(buffer[40]))) {
if (flag)
*flag |= REF_ISBROKEN;
+ errno = EINVAL;
return NULL;
}
return refname;
if (check_refname_format(buf, REFNAME_ALLOW_ONELEVEL)) {
if (flag)
*flag |= REF_ISBROKEN;
+ errno = EINVAL;
return NULL;
}
refname = strcpy(refname_buffer, buf);
if (o->type == OBJ_NONE) {
int type = sha1_object_info(name, NULL);
- if (type < 0)
+ if (type < 0 || !object_as_type(o, type, 0))
return PEEL_INVALID;
- o->type = type;
}
if (o->type != OBJ_TAG)
return 0;
}
+/* 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)
{
if (read_ref_full(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
+ int save_errno = errno;
error("Can't verify ref %s", lock->ref_name);
unlock_ref(lock);
+ errno = save_errno;
return NULL;
}
if (hashcmp(lock->old_sha1, old_sha1)) {
error("Ref %s is at %s but expected %s", lock->ref_name,
sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
unlock_ref(lock);
+ errno = EBUSY;
return NULL;
}
return lock;
* only empty directories), remove them.
*/
struct strbuf path;
- int result;
+ int result, save_errno;
strbuf_init(&path, 20);
strbuf_addstr(&path, file);
result = remove_dir_recursively(&path, REMOVE_DIR_EMPTY_ONLY);
+ save_errno = errno;
strbuf_release(&path);
+ errno = save_errno;
return result;
}
*log = NULL;
for (p = ref_rev_parse_rules; *p; p++) {
- struct stat st;
unsigned char hash[20];
char path[PATH_MAX];
const char *ref, *it;
ref = resolve_ref_unsafe(path, hash, 1, NULL);
if (!ref)
continue;
- if (!stat(git_path("logs/%s", path), &st) &&
- S_ISREG(st.st_mode))
+ if (reflog_exists(path))
it = path;
- else if (strcmp(ref, path) &&
- !stat(git_path("logs/%s", ref), &st) &&
- S_ISREG(st.st_mode))
+ else if (strcmp(ref, path) && reflog_exists(ref))
it = ref;
else
continue;
return logs_found;
}
+/*
+ * Locks a "refs/" ref returning the lock on success and NULL on failure.
+ * On failure errno is set to something meaningful.
+ */
static struct ref_lock *lock_ref_sha1_basic(const char *refname,
const unsigned char *old_sha1,
int flags, int *type_p)
return NULL;
}
-struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
-{
- char refpath[PATH_MAX];
- if (check_refname_format(refname, 0))
- return NULL;
- strcpy(refpath, mkpath("refs/%s", refname));
- return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
-}
-
struct ref_lock *lock_any_ref_for_update(const char *refname,
const unsigned char *old_sha1,
int flags, int *type_p)
return 0;
}
+/* This should return a meaningful errno on failure */
int lock_packed_refs(int flags)
{
struct packed_ref_cache *packed_ref_cache;
return 0;
}
+/*
+ * Commit the packed refs changes.
+ * On error we must make sure that errno contains a meaningful value.
+ */
int commit_packed_refs(void)
{
struct packed_ref_cache *packed_ref_cache =
get_packed_ref_cache(&ref_cache);
int error = 0;
+ int save_errno = 0;
if (!packed_ref_cache->lock)
die("internal error: packed-refs not locked");
do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
0, write_packed_entry_fn,
&packed_ref_cache->lock->fd);
- if (commit_lock_file(packed_ref_cache->lock))
+ if (commit_lock_file(packed_ref_cache->lock)) {
+ save_errno = errno;
error = -1;
+ }
packed_ref_cache->lock = NULL;
release_packed_ref_cache(packed_ref_cache);
+ errno = save_errno;
return error;
}
/* make sure nobody touched the ref, and unlink */
static void prune_ref(struct ref_to_prune *r)
{
- struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
+ struct ref_transaction *transaction;
+ struct strbuf err = STRBUF_INIT;
- if (lock) {
- unlink_or_warn(git_path("%s", r->name));
- unlock_ref(lock);
- try_remove_empty_parents(r->name);
+ if (check_refname_format(r->name, 0))
+ return;
+
+ transaction = ref_transaction_begin(&err);
+ if (!transaction ||
+ ref_transaction_delete(transaction, r->name, r->sha1,
+ REF_ISPRUNING, 1, &err) ||
+ ref_transaction_commit(transaction, NULL, &err)) {
+ ref_transaction_free(transaction);
+ error("%s", err.buf);
+ strbuf_release(&err);
+ return;
}
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
+ try_remove_empty_parents(r->name);
}
static void prune_refs(struct ref_to_prune *r)
return 0;
}
-int repack_without_refs(const char **refnames, int n)
+int repack_without_refs(const char **refnames, int n, 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, removed = 0;
+ int i, ret, removed = 0;
/* Look for a packed ref */
for (i = 0; i < n; i++)
return 0; /* no refname exists in packed refs */
if (lock_packed_refs(0)) {
+ if (err) {
+ unable_to_lock_message(git_path("packed-refs"), errno,
+ err);
+ return -1;
+ }
unable_to_lock_error(git_path("packed-refs"), errno);
return error("cannot delete '%s' from packed refs", refnames[i]);
}
}
/* Write what remains */
- return commit_packed_refs();
-}
-
-static int repack_without_ref(const char *refname)
-{
- return repack_without_refs(&refname, 1);
+ ret = commit_packed_refs();
+ if (ret && err)
+ strbuf_addf(err, "unable to overwrite old ref-pack file: %s",
+ strerror(errno));
+ return ret;
}
static int delete_ref_loose(struct ref_lock *lock, int flag)
int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
{
- struct ref_lock *lock;
- int ret = 0, flag = 0;
-
- lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
- if (!lock)
+ 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), &err) ||
+ ref_transaction_commit(transaction, NULL, &err)) {
+ error("%s", err.buf);
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
return 1;
- ret |= delete_ref_loose(lock, flag);
-
- /* removing the loose one could have resurrected an earlier
- * packed one. Also, if it was not loose we need to repack
- * without it.
- */
- ret |= repack_without_ref(lock->ref_name);
-
- unlink_or_warn(git_path("logs/%s", lock->ref_name));
- clear_loose_ref_cache(&ref_cache);
- unlock_ref(lock);
- return ret;
+ }
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
+ return 0;
}
/*
return cp - buf;
}
+/* This function must set a meaningful errno on failure */
int log_ref_setup(const char *refname, char *logfile, int bufsize)
{
int logfd, oflags = O_APPEND | O_WRONLY;
starts_with(refname, "refs/remotes/") ||
starts_with(refname, "refs/notes/") ||
!strcmp(refname, "HEAD"))) {
- if (safe_create_leading_directories(logfile) < 0)
- return error("unable to create directory for %s",
- logfile);
+ if (safe_create_leading_directories(logfile) < 0) {
+ int save_errno = errno;
+ error("unable to create directory for %s", logfile);
+ errno = save_errno;
+ return -1;
+ }
oflags |= O_CREAT;
}
if ((oflags & O_CREAT) && errno == EISDIR) {
if (remove_empty_directories(logfile)) {
- return error("There are still logs under '%s'",
- logfile);
+ int save_errno = errno;
+ error("There are still logs under '%s'",
+ logfile);
+ errno = save_errno;
+ return -1;
}
logfd = open(logfile, oflags, 0666);
}
- if (logfd < 0)
- return error("Unable to append to %s: %s",
- logfile, strerror(errno));
+ if (logfd < 0) {
+ int save_errno = errno;
+ error("Unable to append to %s: %s", logfile,
+ strerror(errno));
+ errno = save_errno;
+ return -1;
+ }
}
adjust_shared_perm(logfile);
len += copy_msg(logrec + len - 1, msg) - 1;
written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
free(logrec);
- if (close(logfd) != 0 || written != len)
- return error("Unable to append to %s", log_file);
+ if (written != len) {
+ int save_errno = errno;
+ close(logfd);
+ error("Unable to append to %s", log_file);
+ errno = save_errno;
+ return -1;
+ }
+ if (close(logfd)) {
+ int save_errno = errno;
+ error("Unable to append to %s", log_file);
+ errno = save_errno;
+ return -1;
+ }
return 0;
}
-static int is_branch(const char *refname)
+int is_branch(const char *refname)
{
return !strcmp(refname, "HEAD") || starts_with(refname, "refs/heads/");
}
+/* This function must return a meaningful errno */
int write_ref_sha1(struct ref_lock *lock,
const unsigned char *sha1, const char *logmsg)
{
static char term = '\n';
struct object *o;
- if (!lock)
+ if (!lock) {
+ errno = EINVAL;
return -1;
+ }
if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
unlock_ref(lock);
return 0;
error("Trying to write ref %s with nonexistent object %s",
lock->ref_name, sha1_to_hex(sha1));
unlock_ref(lock);
+ errno = EINVAL;
return -1;
}
if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
error("Trying to write non-commit object %s to branch %s",
sha1_to_hex(sha1), lock->ref_name);
unlock_ref(lock);
+ errno = EINVAL;
return -1;
}
if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
- write_in_full(lock->lock_fd, &term, 1) != 1
- || close_ref(lock) < 0) {
+ write_in_full(lock->lock_fd, &term, 1) != 1 ||
+ close_ref(lock) < 0) {
+ int save_errno = errno;
error("Couldn't write %s", lock->lk->filename);
unlock_ref(lock);
+ errno = save_errno;
return -1;
}
clear_loose_ref_cache(&ref_cache);
return 0;
}
-static char *ref_msg(const char *line, const char *endp)
-{
- const char *ep;
- line += 82;
- ep = memchr(line, '\n', endp - line);
- if (!ep)
- ep = endp;
- return xmemdupz(line, ep - line);
+struct read_ref_at_cb {
+ const char *refname;
+ unsigned long at_time;
+ int cnt;
+ int reccnt;
+ unsigned char *sha1;
+ int found_it;
+
+ unsigned char osha1[20];
+ unsigned char nsha1[20];
+ int tz;
+ unsigned long date;
+ char **msg;
+ unsigned long *cutoff_time;
+ int *cutoff_tz;
+ int *cutoff_cnt;
+};
+
+static int read_ref_at_ent(unsigned char *osha1, unsigned char *nsha1,
+ const char *email, unsigned long timestamp, int tz,
+ const char *message, void *cb_data)
+{
+ struct read_ref_at_cb *cb = cb_data;
+
+ cb->reccnt++;
+ cb->tz = tz;
+ cb->date = timestamp;
+
+ if (timestamp <= cb->at_time || cb->cnt == 0) {
+ if (cb->msg)
+ *cb->msg = xstrdup(message);
+ if (cb->cutoff_time)
+ *cb->cutoff_time = timestamp;
+ if (cb->cutoff_tz)
+ *cb->cutoff_tz = tz;
+ if (cb->cutoff_cnt)
+ *cb->cutoff_cnt = cb->reccnt - 1;
+ /*
+ * we have not yet updated cb->[n|o]sha1 so they still
+ * hold the values for the previous record.
+ */
+ if (!is_null_sha1(cb->osha1)) {
+ hashcpy(cb->sha1, nsha1);
+ if (hashcmp(cb->osha1, nsha1))
+ warning("Log for ref %s has gap after %s.",
+ cb->refname, show_date(cb->date, cb->tz, DATE_RFC2822));
+ }
+ else if (cb->date == cb->at_time)
+ hashcpy(cb->sha1, nsha1);
+ else if (hashcmp(nsha1, cb->sha1))
+ warning("Log for ref %s unexpectedly ended on %s.",
+ cb->refname, show_date(cb->date, cb->tz,
+ DATE_RFC2822));
+ hashcpy(cb->osha1, osha1);
+ hashcpy(cb->nsha1, nsha1);
+ cb->found_it = 1;
+ return 1;
+ }
+ hashcpy(cb->osha1, osha1);
+ hashcpy(cb->nsha1, nsha1);
+ if (cb->cnt > 0)
+ cb->cnt--;
+ return 0;
+}
+
+static int read_ref_at_ent_oldest(unsigned char *osha1, unsigned char *nsha1,
+ const char *email, unsigned long timestamp,
+ int tz, const char *message, void *cb_data)
+{
+ struct read_ref_at_cb *cb = cb_data;
+
+ if (cb->msg)
+ *cb->msg = xstrdup(message);
+ if (cb->cutoff_time)
+ *cb->cutoff_time = timestamp;
+ if (cb->cutoff_tz)
+ *cb->cutoff_tz = tz;
+ if (cb->cutoff_cnt)
+ *cb->cutoff_cnt = cb->reccnt;
+ hashcpy(cb->sha1, osha1);
+ if (is_null_sha1(cb->sha1))
+ hashcpy(cb->sha1, nsha1);
+ /* We just want the first entry */
+ return 1;
}
int read_ref_at(const char *refname, unsigned long at_time, int cnt,
unsigned char *sha1, char **msg,
unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
{
- const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
- char *tz_c;
- int logfd, tz, reccnt = 0;
- struct stat st;
- unsigned long date;
- unsigned char logged_sha1[20];
- void *log_mapped;
- size_t mapsz;
+ struct read_ref_at_cb cb;
- logfile = git_path("logs/%s", refname);
- logfd = open(logfile, O_RDONLY, 0);
- if (logfd < 0)
- die_errno("Unable to read log '%s'", logfile);
- fstat(logfd, &st);
- if (!st.st_size)
- die("Log %s is empty.", logfile);
- mapsz = xsize_t(st.st_size);
- log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
- logdata = log_mapped;
- close(logfd);
+ memset(&cb, 0, sizeof(cb));
+ cb.refname = refname;
+ cb.at_time = at_time;
+ cb.cnt = cnt;
+ cb.msg = msg;
+ cb.cutoff_time = cutoff_time;
+ cb.cutoff_tz = cutoff_tz;
+ cb.cutoff_cnt = cutoff_cnt;
+ cb.sha1 = sha1;
+
+ for_each_reflog_ent_reverse(refname, read_ref_at_ent, &cb);
+
+ if (!cb.reccnt)
+ die("Log for %s is empty.", refname);
+ if (cb.found_it)
+ return 0;
+
+ for_each_reflog_ent(refname, read_ref_at_ent_oldest, &cb);
- lastrec = NULL;
- rec = logend = logdata + st.st_size;
- while (logdata < rec) {
- reccnt++;
- if (logdata < rec && *(rec-1) == '\n')
- rec--;
- lastgt = NULL;
- while (logdata < rec && *(rec-1) != '\n') {
- rec--;
- if (*rec == '>')
- lastgt = rec;
- }
- if (!lastgt)
- die("Log %s is corrupt.", logfile);
- date = strtoul(lastgt + 1, &tz_c, 10);
- if (date <= at_time || cnt == 0) {
- tz = strtoul(tz_c, NULL, 10);
- if (msg)
- *msg = ref_msg(rec, logend);
- if (cutoff_time)
- *cutoff_time = date;
- if (cutoff_tz)
- *cutoff_tz = tz;
- if (cutoff_cnt)
- *cutoff_cnt = reccnt - 1;
- if (lastrec) {
- if (get_sha1_hex(lastrec, logged_sha1))
- die("Log %s is corrupt.", logfile);
- if (get_sha1_hex(rec + 41, sha1))
- die("Log %s is corrupt.", logfile);
- if (hashcmp(logged_sha1, sha1)) {
- warning("Log %s has gap after %s.",
- logfile, show_date(date, tz, DATE_RFC2822));
- }
- }
- else if (date == at_time) {
- if (get_sha1_hex(rec + 41, sha1))
- die("Log %s is corrupt.", logfile);
- }
- else {
- if (get_sha1_hex(rec + 41, logged_sha1))
- die("Log %s is corrupt.", logfile);
- if (hashcmp(logged_sha1, sha1)) {
- warning("Log %s unexpectedly ended on %s.",
- logfile, show_date(date, tz, DATE_RFC2822));
- }
- }
- munmap(log_mapped, mapsz);
- return 0;
- }
- lastrec = rec;
- if (cnt > 0)
- cnt--;
- }
-
- rec = logdata;
- while (rec < logend && *rec != '>' && *rec != '\n')
- rec++;
- if (rec == logend || *rec == '\n')
- die("Log %s is corrupt.", logfile);
- date = strtoul(rec + 1, &tz_c, 10);
- tz = strtoul(tz_c, NULL, 10);
- if (get_sha1_hex(logdata, sha1))
- die("Log %s is corrupt.", logfile);
- if (is_null_sha1(sha1)) {
- if (get_sha1_hex(logdata + 41, sha1))
- die("Log %s is corrupt.", logfile);
- }
- if (msg)
- *msg = ref_msg(logdata, logend);
- munmap(log_mapped, mapsz);
-
- if (cutoff_time)
- *cutoff_time = date;
- if (cutoff_tz)
- *cutoff_tz = tz;
- if (cutoff_cnt)
- *cutoff_cnt = reccnt;
return 1;
}
+int reflog_exists(const char *refname)
+{
+ struct stat st;
+
+ return !lstat(git_path("logs/%s", refname), &st) &&
+ S_ISREG(st.st_mode);
+}
+
+int delete_reflog(const char *refname)
+{
+ return remove_path(git_path("logs/%s", refname));
+}
+
static int show_one_reflog_ent(struct strbuf *sb, each_reflog_ent_fn fn, void *cb_data)
{
unsigned char osha1[20], nsha1[20];
if (de->d_name[0] == '.')
continue;
- if (has_extension(de->d_name, ".lock"))
+ if (ends_with(de->d_name, ".lock"))
continue;
strbuf_addstr(name, de->d_name);
if (stat(git_path("logs/%s", name->buf), &st) < 0) {
return retval;
}
-static struct ref_lock *update_ref_lock(const char *refname,
- const unsigned char *oldval,
- int flags, int *type_p,
- enum action_on_err onerr)
-{
+/**
+ * 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.
+ */
+struct ref_update {
+ unsigned char new_sha1[20];
+ unsigned char old_sha1[20];
+ int flags; /* REF_NODEREF? */
+ int have_old; /* 1 if old_sha1 is valid, 0 otherwise */
struct ref_lock *lock;
- lock = lock_any_ref_for_update(refname, oldval, flags, type_p);
- if (!lock) {
- const char *str = "Cannot lock the ref '%s'.";
- switch (onerr) {
- case MSG_ON_ERR: error(str, refname); break;
- case DIE_ON_ERR: die(str, refname); break;
- case QUIET_ON_ERR: break;
- }
- }
- return lock;
+ int type;
+ const char refname[FLEX_ARRAY];
+};
+
+/*
+ * Transaction states.
+ * OPEN: The transaction is in a valid state and can accept new updates.
+ * An OPEN transaction can be committed.
+ * CLOSED: A closed transaction is no longer active and no other operations
+ * than free can be used on it in this state.
+ * A transaction can either become closed by successfully committing
+ * an active transaction or if there is a failure while building
+ * the transaction thus rendering it failed/inactive.
+ */
+enum ref_transaction_state {
+ REF_TRANSACTION_OPEN = 0,
+ REF_TRANSACTION_CLOSED = 1
+};
+
+/*
+ * Data structure for holding a reference transaction, which can
+ * consist of checks and updates to multiple references, carried out
+ * as atomically as possible. This structure is opaque to callers.
+ */
+struct ref_transaction {
+ struct ref_update **updates;
+ size_t alloc;
+ size_t nr;
+ enum ref_transaction_state state;
+};
+
+struct ref_transaction *ref_transaction_begin(struct strbuf *err)
+{
+ return xcalloc(1, sizeof(struct ref_transaction));
}
-static int update_ref_write(const char *action, const char *refname,
- const unsigned char *sha1, struct ref_lock *lock,
- enum action_on_err onerr)
+void ref_transaction_free(struct ref_transaction *transaction)
{
- if (write_ref_sha1(lock, sha1, action) < 0) {
- const char *str = "Cannot update the ref '%s'.";
- switch (onerr) {
- case MSG_ON_ERR: error(str, refname); break;
- case DIE_ON_ERR: die(str, refname); break;
- case QUIET_ON_ERR: break;
- }
- return 1;
+ int i;
+
+ if (!transaction)
+ return;
+
+ for (i = 0; i < transaction->nr; i++)
+ free(transaction->updates[i]);
+
+ free(transaction->updates);
+ free(transaction);
+}
+
+static struct ref_update *add_update(struct ref_transaction *transaction,
+ const char *refname)
+{
+ size_t len = strlen(refname);
+ struct ref_update *update = xcalloc(1, sizeof(*update) + len + 1);
+
+ strcpy((char *)update->refname, refname);
+ ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
+ transaction->updates[transaction->nr++] = update;
+ return update;
+}
+
+int ref_transaction_update(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *new_sha1,
+ const unsigned char *old_sha1,
+ int flags, int have_old,
+ 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");
+
+ update = add_update(transaction, refname);
+ hashcpy(update->new_sha1, new_sha1);
+ update->flags = flags;
+ update->have_old = have_old;
+ if (have_old)
+ hashcpy(update->old_sha1, old_sha1);
+ return 0;
+}
+
+int ref_transaction_create(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *new_sha1,
+ int flags,
+ struct strbuf *err)
+{
+ struct ref_update *update;
+
+ 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");
+
+ update = add_update(transaction, refname);
+
+ hashcpy(update->new_sha1, new_sha1);
+ hashclr(update->old_sha1);
+ update->flags = flags;
+ update->have_old = 1;
+ return 0;
+}
+
+int ref_transaction_delete(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *old_sha1,
+ int flags, int have_old,
+ struct strbuf *err)
+{
+ struct ref_update *update;
+
+ 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");
+
+ 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);
}
return 0;
}
const unsigned char *sha1, const unsigned char *oldval,
int flags, enum action_on_err onerr)
{
- struct ref_lock *lock;
- lock = update_ref_lock(refname, oldval, flags, NULL, onerr);
- if (!lock)
+ 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, &err) ||
+ ref_transaction_commit(t, action, &err)) {
+ 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);
+ break;
+ case UPDATE_REFS_DIE_ON_ERR:
+ die(str, refname, err.buf);
+ break;
+ case UPDATE_REFS_QUIET_ON_ERR:
+ break;
+ }
+ strbuf_release(&err);
return 1;
- return update_ref_write(action, refname, sha1, lock, onerr);
+ }
+ strbuf_release(&err);
+ ref_transaction_free(t);
+ 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)->ref_name, (*u2)->ref_name);
+ return strcmp((*u1)->refname, (*u2)->refname);
}
static int ref_update_reject_duplicates(struct ref_update **updates, int n,
- enum action_on_err onerr)
+ struct strbuf *err)
{
int i;
for (i = 1; i < n; i++)
- if (!strcmp(updates[i - 1]->ref_name, updates[i]->ref_name)) {
+ if (!strcmp(updates[i - 1]->refname, updates[i]->refname)) {
const char *str =
"Multiple updates for ref '%s' not allowed.";
- switch (onerr) {
- case MSG_ON_ERR:
- error(str, updates[i]->ref_name); break;
- case DIE_ON_ERR:
- die(str, updates[i]->ref_name); break;
- case QUIET_ON_ERR:
- break;
- }
+ if (err)
+ strbuf_addf(err, str, updates[i]->refname);
+
return 1;
}
return 0;
}
-int update_refs(const char *action, const struct ref_update **updates_orig,
- int n, enum action_on_err onerr)
+int ref_transaction_commit(struct ref_transaction *transaction,
+ const char *msg, struct strbuf *err)
{
int ret = 0, delnum = 0, i;
- struct ref_update **updates;
- int *types;
- struct ref_lock **locks;
const char **delnames;
+ int n = transaction->nr;
+ struct ref_update **updates = transaction->updates;
- if (!updates_orig || !n)
+ if (transaction->state != REF_TRANSACTION_OPEN)
+ die("BUG: commit called for transaction that is not open");
+
+ if (!n) {
+ transaction->state = REF_TRANSACTION_CLOSED;
return 0;
+ }
/* Allocate work space */
- updates = xmalloc(sizeof(*updates) * n);
- types = xmalloc(sizeof(*types) * n);
- locks = xcalloc(n, sizeof(*locks));
delnames = xmalloc(sizeof(*delnames) * n);
/* Copy, sort, and reject duplicate refs */
- memcpy(updates, updates_orig, sizeof(*updates) * n);
qsort(updates, n, sizeof(*updates), ref_update_compare);
- ret = ref_update_reject_duplicates(updates, n, onerr);
+ ret = ref_update_reject_duplicates(updates, n, err);
if (ret)
goto cleanup;
/* Acquire all locks while verifying old values */
for (i = 0; i < n; i++) {
- locks[i] = update_ref_lock(updates[i]->ref_name,
- (updates[i]->have_old ?
- updates[i]->old_sha1 : NULL),
- updates[i]->flags,
- &types[i], onerr);
- if (!locks[i]) {
+ struct ref_update *update = updates[i];
+
+ update->lock = lock_any_ref_for_update(update->refname,
+ (update->have_old ?
+ update->old_sha1 :
+ NULL),
+ update->flags,
+ &update->type);
+ if (!update->lock) {
+ if (err)
+ strbuf_addf(err, "Cannot lock the ref '%s'.",
+ update->refname);
ret = 1;
goto cleanup;
}
}
/* Perform updates first so live commits remain referenced */
- for (i = 0; i < n; i++)
- if (!is_null_sha1(updates[i]->new_sha1)) {
- ret = update_ref_write(action,
- updates[i]->ref_name,
- updates[i]->new_sha1,
- locks[i], onerr);
- locks[i] = NULL; /* freed by update_ref_write */
- if (ret)
+ for (i = 0; i < n; i++) {
+ struct ref_update *update = updates[i];
+
+ if (!is_null_sha1(update->new_sha1)) {
+ ret = write_ref_sha1(update->lock, update->new_sha1,
+ msg);
+ update->lock = NULL; /* freed by write_ref_sha1 */
+ if (ret) {
+ if (err)
+ strbuf_addf(err, "Cannot update the ref '%s'.",
+ update->refname);
goto cleanup;
+ }
}
+ }
/* Perform deletes now that updates are safely completed */
- for (i = 0; i < n; i++)
- if (locks[i]) {
- delnames[delnum++] = locks[i]->ref_name;
- ret |= delete_ref_loose(locks[i], types[i]);
+ for (i = 0; i < n; i++) {
+ struct ref_update *update = updates[i];
+
+ if (update->lock) {
+ ret |= delete_ref_loose(update->lock, update->type);
+ if (!(update->flags & REF_ISPRUNING))
+ delnames[delnum++] = update->lock->ref_name;
}
- ret |= repack_without_refs(delnames, delnum);
+ }
+
+ ret |= repack_without_refs(delnames, delnum, err);
for (i = 0; i < delnum; i++)
unlink_or_warn(git_path("logs/%s", delnames[i]));
clear_loose_ref_cache(&ref_cache);
cleanup:
+ transaction->state = REF_TRANSACTION_CLOSED;
+
for (i = 0; i < n; i++)
- if (locks[i])
- unlock_ref(locks[i]);
- free(updates);
- free(types);
- free(locks);
+ if (updates[i]->lock)
+ unlock_ref(updates[i]->lock);
free(delnames);
return ret;
}