Fixes for dbi_open/close, ITS#7515

diff --git a/libraries/liblmdb/lmdb.h b/libraries/liblmdb/lmdb.h
index 57c3f886f4396a725d3ae3b4ba4f075d69899337..5cf8bd75ec0c2d1220eb3641eb9f150705fe5ff3 100644 (file)
--- a/libraries/liblmdb/lmdb.h
+++ b/libraries/liblmdb/lmdb.h
@@ -767,14 +767,18 @@ int  mdb_txn_renew(MDB_txn *txn);
        /** @brief Open a database in the environment.
         *
         * The database handle may be discarded by calling #mdb_dbi_close().
-        * It denotes the name and parameters of a database, independently of
-        * whether such a database exists. It will not exist if the transaction
-        * which created it aborted, nor if another process deleted it. The
-        * database handle resides in the shared environment, it is not owned
-        * by the given transaction. Only one thread should call this function;
-        * it is not mutex-protected in a read-only transaction.
-        * Preexisting transactions, other than the current transaction and
-        * any parents, must not use the new handle. Nor must their children.
+        * The old database handle is returned if the database was already open.
+        * The handle must only be closed once.
+        * The database handle will be private to the current transaction until
+        * the transaction is successfully committed. If the transaction is
+        * aborted the handle will be closed automatically.
+        * After a successful commit the
+        * handle will reside in the shared environment, and may be used
+        * by other transactions. This function must not be called from
+        * multiple concurrent transactions. A transaction that uses this function
+        * must finish (either commit or abort) before any other transaction may
+        * use this function.
+        *
         * To use named databases (with name != NULL), #mdb_env_set_maxdbs()
         * must be called before opening the environment.
         * @param[in] txn A transaction handle returned by #mdb_txn_begin()

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 04c8eb8721b7359a80bd11c0241256c0fd04efdb..809b39fab9bc76b776e83cc2a58e79ac10b7fd57 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -745,6 +745,11 @@ typedef struct MDB_db {
        pgno_t          md_root;                /**< the root page of this tree */
 } MDB_db;
 
+       /** mdb_dbi_open flags */
+#define PERSISTENT_FLAGS       0x7fff
+#define VALID_FLAGS    (MDB_REVERSEKEY|MDB_DUPSORT|MDB_INTEGERKEY|MDB_DUPFIXED|\
+       MDB_INTEGERDUP|MDB_REVERSEDUP|MDB_CREATE)
+
        /** Handle for the DB used to track free pages. */
 #define        FREE_DBI        0
        /** Handle for the default DB. */
@@ -824,6 +829,9 @@ struct MDB_txn {
  */
 #define DB_DIRTY       0x01            /**< DB was written in this txn */
 #define DB_STALE       0x02            /**< DB record is older than txnID */
+#define DB_NEW         0x04            /**< DB handle opened in this txn */
+#define DB_VALID       0x08            /**< DB handle is valid */
+#define MDB_VALID      0x8000          /**< DB handle is valid, for me_dbflags */
 /** @} */
        /** In write txns, array of cursors for each DB */
        MDB_cursor      **mt_cursors;
@@ -1770,6 +1778,7 @@ mdb_txn_renew0(MDB_txn *txn)
 {
        MDB_env *env = txn->mt_env;
        unsigned int i;
+       uint16_t x;
        int rc;
 
        /* Setup db info */
@@ -1834,11 +1843,11 @@ mdb_txn_renew0(MDB_txn *txn)
 
        /* Copy the DB info and flags */
        memcpy(txn->mt_dbs, env->me_metas[txn->mt_toggle]->mm_dbs, 2 * sizeof(MDB_db));
-       for (i=2; i<txn->mt_numdbs; i++)
-               txn->mt_dbs[i].md_flags = env->me_dbflags[i];
-       txn->mt_dbflags[0] = txn->mt_dbflags[1] = 0;
-       if (txn->mt_numdbs > 2)
-               memset(txn->mt_dbflags+2, DB_STALE, txn->mt_numdbs-2);
+       for (i=2; i<txn->mt_numdbs; i++) {
+               txn->mt_dbs[i].md_flags = x = env->me_dbflags[i];
+               txn->mt_dbflags[i] = (x & MDB_VALID) ? DB_VALID|DB_STALE : 0;
+       }
+       txn->mt_dbflags[0] = txn->mt_dbflags[1] = DB_VALID;
 
        if (env->me_maxpg < txn->mt_next_pgno) {
                mdb_txn_reset0(txn);
@@ -1912,6 +1921,7 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
        txn->mt_env = env;
 
        if (parent) {
+               unsigned int i;
                txn->mt_free_pgs = mdb_midl_alloc();
                if (!txn->mt_free_pgs) {
                        free(txn);
@@ -1934,7 +1944,9 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
                txn->mt_numdbs = parent->mt_numdbs;
                txn->mt_dbxs = parent->mt_dbxs;
                memcpy(txn->mt_dbs, parent->mt_dbs, txn->mt_numdbs * sizeof(MDB_db));
-               memcpy(txn->mt_dbflags, parent->mt_dbflags, txn->mt_numdbs);
+               /* Copy parent's mt_dbflags, but clear DB_NEW */
+               for (i=0; i<txn->mt_numdbs; i++)
+                       txn->mt_dbflags[i] = parent->mt_dbflags[i] & ~DB_NEW;
                rc = 0;
                ntxn = (MDB_ntxn *)txn;
                ntxn->mnt_pgstate = env->me_pgstate; /* save parent me_pghead & co */
@@ -1973,13 +1985,23 @@ static void
 mdb_txn_reset0(MDB_txn *txn)
 {
        MDB_env *env = txn->mt_env;
+       unsigned int i;
+
+       /* Close any DBI handles opened in this txn */
+       for (i=2; i<txn->mt_numdbs; i++) {
+               if (txn->mt_dbflags[i] & DB_NEW) {
+                       char *ptr = env->me_dbxs[i].md_name.mv_data;
+                       env->me_dbxs[i].md_name.mv_data = NULL;
+                       env->me_dbxs[i].md_name.mv_size = 0;
+                       free(ptr);
+               }
+       }
 
        if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
                if (!(env->me_flags & MDB_ROFS))
                        txn->mt_u.reader->mr_txnid = (txnid_t)-1;
        } else {
                MDB_page *dp;
-               unsigned int i;
 
                /* close(free) all cursors */
                for (i=0; i<txn->mt_numdbs; i++) {
@@ -2083,13 +2105,14 @@ mdb_txn_commit(MDB_txn *txn)
        env = txn->mt_env;
 
        if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
-               if (txn->mt_numdbs > env->me_numdbs) {
-                       /* update the DB flags */
-                       MDB_dbi i;
-                       for (i = env->me_numdbs; i<txn->mt_numdbs; i++)
-                               env->me_dbflags[i] = txn->mt_dbs[i].md_flags;
-                       env->me_numdbs = i;
+               /* update the DB flags */
+               for (i = 2; i<txn->mt_numdbs; i++) {
+                       if (txn->mt_dbflags[i] & DB_NEW)
+                               env->me_dbflags[i] = txn->mt_dbs[i].md_flags | MDB_VALID;
                }
+               if (txn->mt_numdbs > env->me_numdbs)
+                       env->me_numdbs = txn->mt_numdbs;
+               txn->mt_numdbs = 2; /* so txn_abort() doesn't close any new handles */
                mdb_txn_abort(txn);
                return MDB_SUCCESS;
        }
@@ -2122,8 +2145,14 @@ mdb_txn_commit(MDB_txn *txn)
 
                /* Update parent's DB table. */
                memcpy(parent->mt_dbs, txn->mt_dbs, txn->mt_numdbs * sizeof(MDB_db));
-               memcpy(parent->mt_dbflags, txn->mt_dbflags, txn->mt_numdbs);
                txn->mt_parent->mt_numdbs = txn->mt_numdbs;
+               txn->mt_parent->mt_dbflags[0] = txn->mt_dbflags[0];
+               txn->mt_parent->mt_dbflags[1] = txn->mt_dbflags[1];
+               for (i=2; i<txn->mt_numdbs; i++) {
+                       /* preserve parent's DB_NEW status */
+                       x = txn->mt_parent->mt_dbflags[i] & DB_NEW;
+                       txn->mt_parent->mt_dbflags[i] = txn->mt_dbflags[i] | x;
+               }
 
                dst = txn->mt_parent->mt_u.dirty_list;
                src = txn->mt_u.dirty_list;
@@ -2466,13 +2495,13 @@ sync:
 done:
        env->me_pglast = 0;
        env->me_txn = NULL;
-       if (txn->mt_numdbs > env->me_numdbs) {
-               /* update the DB flags */
-               MDB_dbi i;
-               for (i = env->me_numdbs; i<txn->mt_numdbs; i++)
-                       env->me_dbflags[i] = txn->mt_dbs[i].md_flags;
-               env->me_numdbs = i;
+       /* update the DB flags */
+       for (i = 2; i<txn->mt_numdbs; i++) {
+               if (txn->mt_dbflags[i] & DB_NEW)
+                       env->me_dbflags[i] = txn->mt_dbs[i].md_flags | MDB_VALID;
        }
+       if (txn->mt_numdbs > env->me_numdbs)
+               env->me_numdbs = txn->mt_numdbs;
 
        UNLOCK_MUTEX_W(env);
        free(txn);
@@ -4130,13 +4159,14 @@ mdb_page_search(MDB_cursor *mc, MDB_val *key, int flags)
                                        /* The txn may not know this DBI, or another process may
                                         * have dropped and recreated the DB with other flags.
                                         */
-                                       if (mc->mc_db->md_flags != flags)
+                                       if ((mc->mc_db->md_flags & PERSISTENT_FLAGS) != flags)
                                                return MDB_INCOMPATIBLE;
                                        memcpy(mc->mc_db, data.mv_data, sizeof(MDB_db));
                                }
                                if (flags & MDB_PS_MODIFY)
                                        dbflag = DB_DIRTY;
-                               *mc->mc_dbflag = dbflag;
+                               *mc->mc_dbflag &= ~DB_STALE;
+                               *mc->mc_dbflag |= dbflag;
                        }
                }
                root = mc->mc_db->md_root;
@@ -4214,7 +4244,7 @@ mdb_get(MDB_txn *txn, MDB_dbi dbi,
        assert(data);
        DPRINTF("===> get db %u key [%s]", dbi, DKEY(key));
 
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        if (key->mv_size == 0 || key->mv_size > MDB_MAXKEYSIZE) {
@@ -4858,7 +4888,7 @@ mdb_cursor_touch(MDB_cursor *mc)
                rc = mdb_page_search(&mc2, &mc->mc_dbx->md_name, MDB_PS_MODIFY);
                if (rc)
                         return rc;
-               *mc->mc_dbflag = DB_DIRTY;
+               *mc->mc_dbflag |= DB_DIRTY;
        }
        for (mc->mc_top = 0; mc->mc_top < mc->mc_snum; mc->mc_top++) {
                rc = mdb_page_touch(mc);
@@ -4920,7 +4950,7 @@ mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
                mdb_cursor_push(mc, np);
                mc->mc_db->md_root = np->mp_pgno;
                mc->mc_db->md_depth++;
-               *mc->mc_dbflag = DB_DIRTY;
+               *mc->mc_dbflag |= DB_DIRTY;
                if ((mc->mc_db->md_flags & (MDB_DUPSORT|MDB_DUPFIXED))
                        == MDB_DUPFIXED)
                        np->mp_flags |= P_LEAF2;
@@ -5714,8 +5744,8 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node)
        }
        DPRINTF("Sub-db %u for db %u root page %zu", mx->mx_cursor.mc_dbi, mc->mc_dbi,
                mx->mx_db.md_root);
-       mx->mx_dbflag = (F_ISSET(mc->mc_pg[mc->mc_top]->mp_flags, P_DIRTY)) ?
-               DB_DIRTY : 0;
+       mx->mx_dbflag = DB_VALID | (F_ISSET(mc->mc_pg[mc->mc_top]->mp_flags, P_DIRTY) ?
+               DB_DIRTY : 0);
        mx->mx_dbx.md_name.mv_data = NODEKEY(node);
        mx->mx_dbx.md_name.mv_size = node->mn_ksize;
 #if UINT_MAX < SIZE_MAX
@@ -5761,7 +5791,7 @@ mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret)
        MDB_xcursor     *mx = NULL;
        size_t size = sizeof(MDB_cursor);
 
-       if (txn == NULL || ret == NULL || dbi >= txn->mt_numdbs)
+       if (txn == NULL || ret == NULL || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        /* Allow read access to the freelist */
@@ -6457,7 +6487,7 @@ mdb_del(MDB_txn *txn, MDB_dbi dbi,
 
        DPRINTF("====> delete db %u key [%s]", dbi, DKEY(key));
 
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
@@ -6908,7 +6938,7 @@ mdb_put(MDB_txn *txn, MDB_dbi dbi,
        assert(key != NULL);
        assert(data != NULL);
 
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
@@ -7030,15 +7060,11 @@ mdb_default_cmp(MDB_txn *txn, MDB_dbi dbi)
                 : ((f & MDB_REVERSEDUP) ? mdb_cmp_memnr : mdb_cmp_memn));
 }
 
-#define PERSISTENT_FLAGS       0xffff
-#define VALID_FLAGS    (MDB_REVERSEKEY|MDB_DUPSORT|MDB_INTEGERKEY|MDB_DUPFIXED|\
-       MDB_INTEGERDUP|MDB_REVERSEDUP|MDB_CREATE)
 int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
 {
        MDB_val key, data;
        MDB_dbi i;
        MDB_cursor mc;
-       uint16_t mdflags;
        int rc, dbflag, exact;
        unsigned int unused = 0;
        size_t len;
@@ -7089,7 +7115,7 @@ int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *db
                return MDB_DBS_FULL;
 
        /* Find the DB info */
-       dbflag = 0;
+       dbflag = DB_NEW|DB_VALID;
        exact = 0;
        key.mv_size = len;
        key.mv_data = (void *)name;
@@ -7109,7 +7135,7 @@ int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *db
                dummy.md_root = P_INVALID;
                dummy.md_flags = flags & PERSISTENT_FLAGS;
                rc = mdb_cursor_put(&mc, &key, &data, F_SUBDATA);
-               dbflag = DB_DIRTY;
+               dbflag |= DB_DIRTY;
        }
 
        /* OK, got info, add to table */
@@ -7121,18 +7147,10 @@ int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *db
                txn->mt_dbflags[slot] = dbflag;
                memcpy(&txn->mt_dbs[slot], data.mv_data, sizeof(MDB_db));
                *dbi = slot;
-               txn->mt_env->me_dbflags[slot] = mdflags = txn->mt_dbs[slot].md_flags;
+               txn->mt_env->me_dbflags[slot] = txn->mt_dbs[slot].md_flags;
                mdb_default_cmp(txn, slot);
                if (!unused) {
                        txn->mt_numdbs++;
-                       txn->mt_env->me_numdbs++;
-               }
-               /* Open the DB in parent txns as well */
-               while ((txn = txn->mt_parent) != NULL) {
-                       txn->mt_dbflags[slot] = DB_STALE;
-                       txn->mt_dbs[slot].md_flags = mdflags;
-                       if (!unused)
-                               txn->mt_numdbs++;
                }
        }
 
@@ -7235,7 +7253,7 @@ int mdb_drop(MDB_txn *txn, MDB_dbi dbi, int del)
        MDB_cursor *mc;
        int rc;
 
-       if (!txn || !dbi || dbi >= txn->mt_numdbs || (unsigned)del > 1)
+       if (!txn || !dbi || dbi >= txn->mt_numdbs || (unsigned)del > 1 || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
@@ -7275,7 +7293,7 @@ leave:
 
 int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
 {
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        txn->mt_dbxs[dbi].md_cmp = cmp;
@@ -7284,7 +7302,7 @@ int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
 
 int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
 {
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        txn->mt_dbxs[dbi].md_dcmp = cmp;
@@ -7293,7 +7311,7 @@ int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
 
 int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel)
 {
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        txn->mt_dbxs[dbi].md_rel = rel;
@@ -7302,7 +7320,7 @@ int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel)
 
 int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx)
 {
-       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+       if (txn == NULL || !dbi || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
                return EINVAL;
 
        txn->mt_dbxs[dbi].md_relctx = ctx;