]> git.ozlabs.org Git - ccan/blobdiff - ccan/tdb2/lock.c
tdb2: rename tdb_lock_type to tdb_lock
[ccan] / ccan / tdb2 / lock.c
index c5dd084e82bf04af7c1dee6b12996f25749276cc..8e73c253cb5ba4eac0ba9cc3c54fbe62ecbc9132 100644 (file)
@@ -42,10 +42,10 @@ static int fcntl_lock(struct tdb_context *tdb,
 
        add_stat(tdb, lock_lowlevel, 1);
        if (waitflag)
-               return fcntl(tdb->fd, F_SETLKW, &fl);
+               return fcntl(tdb->file->fd, F_SETLKW, &fl);
        else {
                add_stat(tdb, lock_nonblock, 1);
-               return fcntl(tdb->fd, F_SETLK, &fl);
+               return fcntl(tdb->file->fd, F_SETLK, &fl);
        }
 }
 
@@ -116,11 +116,11 @@ static int fcntl_unlock(struct tdb_context *tdb, int rw, off_t off, off_t len)
        fl.l_len = len;
        fl.l_pid = 0;
 
-       return fcntl(tdb->fd, F_SETLKW, &fl);
+       return fcntl(tdb->file->fd, F_SETLKW, &fl);
 }
 
 /* a byte range locking function - return 0 on success
-   this functions locks/unlocks 1 byte at the specified offset.
+   this functions locks len bytes at the specified offset.
 
    note that a len of zero means lock to end of file
 */
@@ -161,7 +161,7 @@ static enum TDB_ERROR tdb_brlock(struct tdb_context *tdb,
                                   "tdb_brlock failed (fd=%d) at"
                                   " offset %zu rw_type=%d flags=%d len=%zu:"
                                   " %s",
-                                  tdb->fd, (size_t)offset, rw_type,
+                                  tdb->file->fd, (size_t)offset, rw_type,
                                   flags, (size_t)len, strerror(errno));
                }
                return TDB_ERR_LOCK;
@@ -186,7 +186,7 @@ static enum TDB_ERROR tdb_brunlock(struct tdb_context *tdb,
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_brunlock failed (fd=%d) at offset %zu"
                                  " rw_type=%d len=%zu",
-                                 tdb->fd, (size_t)offset, rw_type,
+                                 tdb->file->fd, (size_t)offset, rw_type,
                                  (size_t)len);
        }
        return TDB_SUCCESS;
@@ -202,14 +202,14 @@ enum TDB_ERROR tdb_allrecord_upgrade(struct tdb_context *tdb)
 {
        int count = 1000;
 
-       if (tdb->allrecord_lock.count != 1) {
+       if (tdb->file->allrecord_lock.count != 1) {
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_allrecord_upgrade failed:"
                                  " count %u too high",
-                                 tdb->allrecord_lock.count);
+                                 tdb->file->allrecord_lock.count);
        }
 
-       if (tdb->allrecord_lock.off != 1) {
+       if (tdb->file->allrecord_lock.off != 1) {
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_allrecord_upgrade failed:"
                                  " already upgraded?");
@@ -220,8 +220,8 @@ enum TDB_ERROR tdb_allrecord_upgrade(struct tdb_context *tdb)
                if (tdb_brlock(tdb, F_WRLCK,
                               TDB_HASH_LOCK_START, 0,
                               TDB_LOCK_WAIT|TDB_LOCK_PROBE) == TDB_SUCCESS) {
-                       tdb->allrecord_lock.ltype = F_WRLCK;
-                       tdb->allrecord_lock.off = 0;
+                       tdb->file->allrecord_lock.ltype = F_WRLCK;
+                       tdb->file->allrecord_lock.off = 0;
                        return TDB_SUCCESS;
                }
                if (errno != EDEADLK) {
@@ -236,14 +236,13 @@ enum TDB_ERROR tdb_allrecord_upgrade(struct tdb_context *tdb)
                          "tdb_allrecord_upgrade failed");
 }
 
-static struct tdb_lock_type *find_nestlock(struct tdb_context *tdb,
-                                          tdb_off_t offset)
+static struct tdb_lock *find_nestlock(struct tdb_context *tdb, tdb_off_t offset)
 {
        unsigned int i;
 
-       for (i=0; i<tdb->num_lockrecs; i++) {
-               if (tdb->lockrecs[i].off == offset) {
-                       return &tdb->lockrecs[i];
+       for (i=0; i<tdb->file->num_lockrecs; i++) {
+               if (tdb->file->lockrecs[i].off == offset) {
+                       return &tdb->file->lockrecs[i];
                }
        }
        return NULL;
@@ -276,10 +275,11 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
                                    tdb_off_t offset, int ltype,
                                    enum tdb_lock_flags flags)
 {
-       struct tdb_lock_type *new_lck;
+       struct tdb_lock *new_lck;
        enum TDB_ERROR ecode;
 
-       if (offset > TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE + tdb->map_size / 8) {
+       if (offset > (TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE
+                     + tdb->file->map_size / 8)) {
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_nest_lock: invalid offset %zu ltype=%d",
                                  (size_t)offset, ltype);
@@ -303,23 +303,23 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
                return TDB_SUCCESS;
        }
 
-       if (tdb->num_lockrecs
+       if (tdb->file->num_lockrecs
            && offset >= TDB_HASH_LOCK_START
            && offset < TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE) {
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_nest_lock: already have a hash lock?");
        }
 
-       new_lck = (struct tdb_lock_type *)realloc(
-               tdb->lockrecs,
-               sizeof(*tdb->lockrecs) * (tdb->num_lockrecs+1));
+       new_lck = (struct tdb_lock *)realloc(
+               tdb->file->lockrecs,
+               sizeof(*tdb->file->lockrecs) * (tdb->file->num_lockrecs+1));
        if (new_lck == NULL) {
                return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
                                  "tdb_nest_lock:"
                                  " unable to allocate %zu lock struct",
-                                 tdb->num_lockrecs + 1);
+                                 tdb->file->num_lockrecs + 1);
        }
-       tdb->lockrecs = new_lck;
+       tdb->file->lockrecs = new_lck;
 
        /* Since fcntl locks don't nest, we do a lock for the first one,
           and simply bump the count for future ones */
@@ -330,7 +330,7 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
 
        /* First time we grab a lock, perhaps someone died in commit? */
        if (!(flags & TDB_LOCK_NOCHECK)
-           && tdb->num_lockrecs == 0) {
+           && tdb->file->num_lockrecs == 0) {
                tdb_bool_err berr = tdb_needs_recovery(tdb);
                if (berr != false) {
                        tdb_brunlock(tdb, ltype, offset, 1);
@@ -348,10 +348,10 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
                }
        }
 
-       tdb->lockrecs[tdb->num_lockrecs].off = offset;
-       tdb->lockrecs[tdb->num_lockrecs].count = 1;
-       tdb->lockrecs[tdb->num_lockrecs].ltype = ltype;
-       tdb->num_lockrecs++;
+       tdb->file->lockrecs[tdb->file->num_lockrecs].off = offset;
+       tdb->file->lockrecs[tdb->file->num_lockrecs].count = 1;
+       tdb->file->lockrecs[tdb->file->num_lockrecs].ltype = ltype;
+       tdb->file->num_lockrecs++;
 
        return TDB_SUCCESS;
 }
@@ -359,7 +359,7 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
 static enum TDB_ERROR tdb_nest_unlock(struct tdb_context *tdb,
                                      tdb_off_t off, int ltype)
 {
-       struct tdb_lock_type *lck;
+       struct tdb_lock *lck;
        enum TDB_ERROR ecode;
 
        if (tdb->flags & TDB_NOLOCK)
@@ -389,7 +389,7 @@ static enum TDB_ERROR tdb_nest_unlock(struct tdb_context *tdb,
         * Shrink the array by overwriting the element just unlocked with the
         * last array element.
         */
-       *lck = tdb->lockrecs[--tdb->num_lockrecs];
+       *lck = tdb->file->lockrecs[--tdb->file->num_lockrecs];
 
        return ecode;
 }
@@ -452,23 +452,18 @@ enum TDB_ERROR tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
        enum TDB_ERROR ecode;
        tdb_bool_err berr;
 
-       /* FIXME: There are no locks on read-only dbs */
-       if (tdb->read_only) {
-               return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
-                                 "tdb_allrecord_lock: read-only");
-       }
-
-       if (tdb->allrecord_lock.count
-           && (ltype == F_RDLCK || tdb->allrecord_lock.ltype == F_WRLCK)) {
-               tdb->allrecord_lock.count++;
+       if (tdb->file->allrecord_lock.count
+           && (ltype == F_RDLCK
+               || tdb->file->allrecord_lock.ltype == F_WRLCK)) {
+               tdb->file->allrecord_lock.count++;
                return TDB_SUCCESS;
        }
 
-       if (tdb->allrecord_lock.count) {
+       if (tdb->file->allrecord_lock.count) {
                /* a global lock of a different type exists */
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
                                  "tdb_allrecord_lock: already have %s lock",
-                                 tdb->allrecord_lock.ltype == F_RDLCK
+                                 tdb->file->allrecord_lock.ltype == F_RDLCK
                                  ? "read" : "write");
        }
 
@@ -513,11 +508,11 @@ again:
                return ecode;
        }
 
-       tdb->allrecord_lock.count = 1;
+       tdb->file->allrecord_lock.count = 1;
        /* If it's upgradable, it's actually exclusive so we can treat
         * it as a write lock. */
-       tdb->allrecord_lock.ltype = upgradable ? F_WRLCK : ltype;
-       tdb->allrecord_lock.off = upgradable;
+       tdb->file->allrecord_lock.ltype = upgradable ? F_WRLCK : ltype;
+       tdb->file->allrecord_lock.off = upgradable;
 
        /* Now check for needing recovery. */
        if (flags & TDB_LOCK_NOCHECK)
@@ -549,7 +544,8 @@ void tdb_unlock_open(struct tdb_context *tdb)
 
 bool tdb_has_open_lock(struct tdb_context *tdb)
 {
-       return find_nestlock(tdb, TDB_OPEN_LOCK) != NULL;
+       return !(tdb->flags & TDB_NOLOCK)
+               && find_nestlock(tdb, TDB_OPEN_LOCK) != NULL;
 }
 
 enum TDB_ERROR tdb_lock_expand(struct tdb_context *tdb, int ltype)
@@ -567,29 +563,29 @@ void tdb_unlock_expand(struct tdb_context *tdb, int ltype)
 /* unlock entire db */
 void tdb_allrecord_unlock(struct tdb_context *tdb, int ltype)
 {
-       if (tdb->allrecord_lock.count == 0) {
+       if (tdb->file->allrecord_lock.count == 0) {
                tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
                           "tdb_allrecord_unlock: not locked!");
                return;
        }
 
        /* Upgradable locks are marked as write locks. */
-       if (tdb->allrecord_lock.ltype != ltype
-           && (!tdb->allrecord_lock.off || ltype != F_RDLCK)) {
+       if (tdb->file->allrecord_lock.ltype != ltype
+           && (!tdb->file->allrecord_lock.off || ltype != F_RDLCK)) {
                tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                           "tdb_allrecord_unlock: have %s lock",
-                          tdb->allrecord_lock.ltype == F_RDLCK
+                          tdb->file->allrecord_lock.ltype == F_RDLCK
                           ? "read" : "write");
                return;
        }
 
-       if (tdb->allrecord_lock.count > 1) {
-               tdb->allrecord_lock.count--;
+       if (tdb->file->allrecord_lock.count > 1) {
+               tdb->file->allrecord_lock.count--;
                return;
        }
 
-       tdb->allrecord_lock.count = 0;
-       tdb->allrecord_lock.ltype = 0;
+       tdb->file->allrecord_lock.count = 0;
+       tdb->file->allrecord_lock.ltype = 0;
 
        tdb_brunlock(tdb, ltype, TDB_HASH_LOCK_START, 0);
 }
@@ -603,10 +599,10 @@ bool tdb_has_hash_locks(struct tdb_context *tdb)
 {
        unsigned int i;
 
-       for (i=0; i<tdb->num_lockrecs; i++) {
-               if (tdb->lockrecs[i].off >= TDB_HASH_LOCK_START
-                   && tdb->lockrecs[i].off < (TDB_HASH_LOCK_START
-                                              + TDB_HASH_LOCK_RANGE))
+       for (i=0; i<tdb->file->num_lockrecs; i++) {
+               if (tdb->file->lockrecs[i].off >= TDB_HASH_LOCK_START
+                   && tdb->file->lockrecs[i].off < (TDB_HASH_LOCK_START
+                                                    + TDB_HASH_LOCK_RANGE))
                        return true;
        }
        return false;
@@ -616,8 +612,11 @@ static bool tdb_has_free_lock(struct tdb_context *tdb)
 {
        unsigned int i;
 
-       for (i=0; i<tdb->num_lockrecs; i++) {
-               if (tdb->lockrecs[i].off
+       if (tdb->flags & TDB_NOLOCK)
+               return false;
+
+       for (i=0; i<tdb->file->num_lockrecs; i++) {
+               if (tdb->file->lockrecs[i].off
                    > TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE)
                        return true;
        }
@@ -634,16 +633,16 @@ enum TDB_ERROR tdb_lock_hashes(struct tdb_context *tdb,
                + (hash_lock >> (64 - TDB_HASH_LOCK_RANGE_BITS));
 
        /* a allrecord lock allows us to avoid per chain locks */
-       if (tdb->allrecord_lock.count &&
-           (ltype == tdb->allrecord_lock.ltype || ltype == F_RDLCK)) {
+       if (tdb->file->allrecord_lock.count &&
+           (ltype == tdb->file->allrecord_lock.ltype || ltype == F_RDLCK)) {
                return TDB_SUCCESS;
        }
 
-       if (tdb->allrecord_lock.count) {
+       if (tdb->file->allrecord_lock.count) {
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
                                  "tdb_lock_hashes:"
                                  " already have %s allrecordlock",
-                                 tdb->allrecord_lock.ltype == F_RDLCK
+                                 tdb->file->allrecord_lock.ltype == F_RDLCK
                                  ? "read" : "write");
        }
 
@@ -668,9 +667,12 @@ enum TDB_ERROR tdb_unlock_hashes(struct tdb_context *tdb,
        unsigned lock = TDB_HASH_LOCK_START
                + (hash_lock >> (64 - TDB_HASH_LOCK_RANGE_BITS));
 
+       if (tdb->flags & TDB_NOLOCK)
+               return 0;
+
        /* a allrecord lock allows us to avoid per chain locks */
-       if (tdb->allrecord_lock.count) {
-               if (tdb->allrecord_lock.ltype == F_RDLCK
+       if (tdb->file->allrecord_lock.count) {
+               if (tdb->file->allrecord_lock.ltype == F_RDLCK
                    && ltype == F_WRLCK) {
                        return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                          "tdb_unlock_hashes RO allrecord!");
@@ -697,9 +699,12 @@ enum TDB_ERROR tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
 {
        assert(b_off >= sizeof(struct tdb_header));
 
+       if (tdb->flags & TDB_NOLOCK)
+               return 0;
+
        /* a allrecord lock allows us to avoid per chain locks */
-       if (tdb->allrecord_lock.count) {
-               if (tdb->allrecord_lock.ltype == F_WRLCK)
+       if (tdb->file->allrecord_lock.count) {
+               if (tdb->file->allrecord_lock.ltype == F_WRLCK)
                        return 0;
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_lock_free_bucket with"
@@ -719,15 +724,8 @@ enum TDB_ERROR tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
 
 void tdb_unlock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off)
 {
-       if (tdb->allrecord_lock.count)
+       if (tdb->file->allrecord_lock.count)
                return;
 
        tdb_nest_unlock(tdb, free_lock_off(b_off), F_WRLCK);
 }
-
-void tdb_lock_init(struct tdb_context *tdb)
-{
-       tdb->num_lockrecs = 0;
-       tdb->lockrecs = NULL;
-       tdb->allrecord_lock.count = 0;
-}