tdb2: allow multiple opens of the same file.

[ccan] / ccan / tdb2 / lock.c

diff --git a/ccan/tdb2/lock.c b/ccan/tdb2/lock.c
index 82fcdf17d1e6dfd0126d17232826cc53391329ee..17e80d70caef02610af5fc76efcefc1556f614c6 100644 (file)
--- a/ccan/tdb2/lock.c
+++ b/ccan/tdb2/lock.c
@@ -30,14 +30,11 @@
 #include <ccan/build_assert/build_assert.h>
 
 /* If we were threaded, we could wait for unlock, but we're not, so fail. */
-static bool owner_conflict(struct tdb_context *tdb, struct tdb_lock *lock)
+static enum TDB_ERROR owner_conflict(struct tdb_context *tdb, const char *call)
 {
-       if (lock->owner != tdb) {
-               tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
-                          "Lock already owned by another opener");
-               return true;
-       }
-       return false;
+       return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+                         "%s: lock owned by another tdb in this process.",
+                         call);
 }
 
 static int fcntl_lock(struct tdb_context *tdb,
@@ -226,6 +223,10 @@ enum TDB_ERROR tdb_allrecord_upgrade(struct tdb_context *tdb)
                                  " already upgraded?");
        }
 
+       if (tdb->file->allrecord_lock.owner != tdb) {
+               return owner_conflict(tdb, "tdb_allrecord_upgrade");
+       }
+
        while (count--) {
                struct timeval tv;
                if (tdb_brlock(tdb, F_WRLCK,
@@ -306,8 +307,9 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
 
        new_lck = find_nestlock(tdb, offset, NULL);
        if (new_lck) {
-               if (owner_conflict(tdb, new_lck))
-                       return -1;
+               if (new_lck->owner != tdb) {
+                       return owner_conflict(tdb, "tdb_nest_lock");
+               }
 
                if (new_lck->ltype == F_RDLCK && ltype == F_WRLCK) {
                        return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
@@ -470,14 +472,17 @@ enum TDB_ERROR tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
        enum TDB_ERROR ecode;
        tdb_bool_err berr;
 
-       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->file->allrecord_lock.count) {
+               if (tdb->file->allrecord_lock.owner != tdb) {
+                       return owner_conflict(tdb, "tdb_allrecord_lock");
+               }
+
+               if (ltype == F_RDLCK
+                   || tdb->file->allrecord_lock.ltype == F_WRLCK) {
+                       tdb->file->allrecord_lock.count++;
+                       return TDB_SUCCESS;
+               }
+
                /* 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",
@@ -658,12 +663,14 @@ 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->file->allrecord_lock.count &&
-           (ltype == tdb->file->allrecord_lock.ltype || ltype == F_RDLCK)) {
-               return TDB_SUCCESS;
-       }
-
        if (tdb->file->allrecord_lock.count) {
+               if (tdb->file->allrecord_lock.owner != tdb)
+                       return owner_conflict(tdb, "tdb_lock_hashes");
+               if (ltype == tdb->file->allrecord_lock.ltype
+                   || ltype == F_RDLCK) {
+                       return TDB_SUCCESS;
+               }
+
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
                                  "tdb_lock_hashes:"
                                  " already have %s allrecordlock",