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Diffstat (limited to 'refs.c')
-rw-r--r--refs.c245
1 files changed, 140 insertions, 105 deletions
diff --git a/refs.c b/refs.c
index 27927f2..808e261 100644
--- a/refs.c
+++ b/refs.c
@@ -25,6 +25,11 @@ static unsigned char refname_disposition[256] = {
};
/*
+ * 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
@@ -2068,7 +2073,10 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
return logs_found;
}
-/* This function should make sure errno is meaningful on error */
+/*
+ * 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)
@@ -2169,15 +2177,6 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
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)
@@ -2387,13 +2386,25 @@ static void try_remove_empty_parents(char *name)
/* 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 + 5, 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)
@@ -2536,11 +2547,6 @@ int repack_without_refs(const char **refnames, int n, struct strbuf *err)
return ret;
}
-static int repack_without_ref(const char *refname)
-{
- return repack_without_refs(&refname, 1, NULL);
-}
-
static int delete_ref_loose(struct ref_lock *lock, int flag)
{
if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
@@ -2558,24 +2564,22 @@ 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;
}
/*
@@ -3332,43 +3336,6 @@ int for_each_reflog(each_ref_fn fn, void *cb_data)
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)
-{
- 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 UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;
- case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;
- case UPDATE_REFS_QUIET_ON_ERR: break;
- }
- }
- return lock;
-}
-
-static int update_ref_write(const char *action, const char *refname,
- const unsigned char *sha1, struct ref_lock *lock,
- struct strbuf *err, enum action_on_err onerr)
-{
- if (write_ref_sha1(lock, sha1, action) < 0) {
- const char *str = "Cannot update the ref '%s'.";
- if (err)
- strbuf_addf(err, str, refname);
-
- switch (onerr) {
- case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;
- case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;
- case UPDATE_REFS_QUIET_ON_ERR: break;
- }
- return 1;
- }
- return 0;
-}
-
/**
* 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
@@ -3386,6 +3353,21 @@ struct ref_update {
};
/*
+ * 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.
@@ -3394,9 +3376,10 @@ struct ref_transaction {
struct ref_update **updates;
size_t alloc;
size_t nr;
+ enum ref_transaction_state state;
};
-struct ref_transaction *ref_transaction_begin(void)
+struct ref_transaction *ref_transaction_begin(struct strbuf *err)
{
return xcalloc(1, sizeof(struct ref_transaction));
}
@@ -3436,6 +3419,9 @@ int ref_transaction_update(struct ref_transaction *transaction,
{
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");
@@ -3448,44 +3434,84 @@ int ref_transaction_update(struct ref_transaction *transaction,
return 0;
}
-void ref_transaction_create(struct ref_transaction *transaction,
- const char *refname,
- const unsigned char *new_sha1,
- int flags)
+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 = add_update(transaction, refname);
+ 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);
- assert(!is_null_sha1(new_sha1));
hashcpy(update->new_sha1, new_sha1);
hashclr(update->old_sha1);
update->flags = flags;
update->have_old = 1;
+ return 0;
}
-void ref_transaction_delete(struct ref_transaction *transaction,
- const char *refname,
- const unsigned char *old_sha1,
- int flags, int have_old)
+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 = add_update(transaction, refname);
+ 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;
}
int update_ref(const char *action, const char *refname,
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, NULL, onerr);
+ }
+ strbuf_release(&err);
+ ref_transaction_free(t);
+ return 0;
}
static int ref_update_compare(const void *r1, const void *r2)
@@ -3519,8 +3545,13 @@ int ref_transaction_commit(struct ref_transaction *transaction,
int n = transaction->nr;
struct ref_update **updates = transaction->updates;
- if (!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 */
delnames = xmalloc(sizeof(*delnames) * n);
@@ -3535,12 +3566,12 @@ int ref_transaction_commit(struct ref_transaction *transaction,
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
- update->lock = update_ref_lock(update->refname,
- (update->have_old ?
- update->old_sha1 : NULL),
- update->flags,
- &update->type,
- UPDATE_REFS_QUIET_ON_ERR);
+ 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'.",
@@ -3555,14 +3586,15 @@ int ref_transaction_commit(struct ref_transaction *transaction,
struct ref_update *update = updates[i];
if (!is_null_sha1(update->new_sha1)) {
- ret = update_ref_write(msg,
- update->refname,
- update->new_sha1,
- update->lock, err,
- UPDATE_REFS_QUIET_ON_ERR);
- update->lock = NULL; /* freed by update_ref_write */
- if (ret)
+ 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;
+ }
}
}
@@ -3571,8 +3603,9 @@ int ref_transaction_commit(struct ref_transaction *transaction,
struct ref_update *update = updates[i];
if (update->lock) {
- delnames[delnum++] = update->lock->ref_name;
ret |= delete_ref_loose(update->lock, update->type);
+ if (!(update->flags & REF_ISPRUNING))
+ delnames[delnum++] = update->lock->ref_name;
}
}
@@ -3582,6 +3615,8 @@ int ref_transaction_commit(struct ref_transaction *transaction,
clear_loose_ref_cache(&ref_cache);
cleanup:
+ transaction->state = REF_TRANSACTION_CLOSED;
+
for (i = 0; i < n; i++)
if (updates[i]->lock)
unlock_ref(updates[i]->lock);