ITS#7825 more

Set read txn's dbiseqs to env's. Set child txn's dbiseqs to parent's.
Simplify DBI_CHANGED test, no need to check md_name. No-op dbi_close
of already closed handle.

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 0520eb72d51dd55fdc55abca99d05066997e64e2..96e37bcbb831acdb56d805a109d8dccc6b2518d6 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -1149,8 +1149,8 @@ typedef struct MDB_ntxn {
        ((txn) && (dbi) < (txn)->mt_numdbs && ((txn)->mt_dbflags[dbi] & DB_VALID))
 
        /** Check for misused \b dbi handles */
-#define TXN_DBI_CHANGED(txn, md_name, dbi) \
-       (!(md_name).mv_size || (txn)->mt_dbiseqs[dbi] != (txn)->mt_env->me_dbiseqs[dbi])
+#define TXN_DBI_CHANGED(txn, dbi) \
+       ((txn)->mt_dbiseqs[dbi] != (txn)->mt_env->me_dbiseqs[dbi])
 
 static int  mdb_page_alloc(MDB_cursor *mc, int num, MDB_page **mp);
 static int  mdb_page_new(MDB_cursor *mc, uint32_t flags, int num, MDB_page **mp);
@@ -2564,8 +2564,12 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
                tsize = sizeof(MDB_ntxn);
        }
        size = tsize + env->me_maxdbs * (sizeof(MDB_db)+1);
-       if (!(flags & MDB_RDONLY))
-               size += env->me_maxdbs * (sizeof(MDB_cursor *)+sizeof(unsigned int));
+       if (!(flags & MDB_RDONLY)) {
+               size += env->me_maxdbs * sizeof(MDB_cursor *);
+               /* child txns use parent's dbiseqs */
+               if (!parent)
+                       size += env->me_maxdbs * sizeof(unsigned int);
+       }
 
        if ((txn = calloc(1, size)) == NULL) {
                DPRINTF(("calloc: %s", strerror(ErrCode())));
@@ -2575,10 +2579,16 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
        if (flags & MDB_RDONLY) {
                txn->mt_flags |= MDB_TXN_RDONLY;
                txn->mt_dbflags = (unsigned char *)(txn->mt_dbs + env->me_maxdbs);
+               txn->mt_dbiseqs = env->me_dbiseqs;
        } else {
                txn->mt_cursors = (MDB_cursor **)(txn->mt_dbs + env->me_maxdbs);
-               txn->mt_dbiseqs = (unsigned int *)(txn->mt_cursors + env->me_maxdbs);
-               txn->mt_dbflags = (unsigned char *)(txn->mt_dbiseqs + env->me_maxdbs);
+               if (parent) {
+                       txn->mt_dbiseqs = parent->mt_dbiseqs;
+                       txn->mt_dbflags = (unsigned char *)(txn->mt_cursors + env->me_maxdbs);
+               } else {
+                       txn->mt_dbiseqs = (unsigned int *)(txn->mt_cursors + env->me_maxdbs);
+                       txn->mt_dbflags = (unsigned char *)(txn->mt_dbiseqs + env->me_maxdbs);
+               }
        }
        txn->mt_env = env;
 
@@ -2658,11 +2668,13 @@ mdb_dbis_update(MDB_txn *txn, int keep)
                                env->me_dbflags[i] = txn->mt_dbs[i].md_flags | MDB_VALID;
                        } else {
                                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;
-                               env->me_dbflags[i] = 0;
-                               env->me_dbiseqs[i]++;
-                               free(ptr);
+                               if (ptr) {
+                                       env->me_dbxs[i].md_name.mv_data = NULL;
+                                       env->me_dbxs[i].md_name.mv_size = 0;
+                                       env->me_dbflags[i] = 0;
+                                       env->me_dbiseqs[i]++;
+                                       free(ptr);
+                               }
                        }
                }
        }
@@ -3252,7 +3264,7 @@ mdb_txn_commit(MDB_txn *txn)
                mdb_cursor_init(&mc, txn, MAIN_DBI, NULL);
                for (i = 2; i < txn->mt_numdbs; i++) {
                        if (txn->mt_dbflags[i] & DB_DIRTY) {
-                               if (TXN_DBI_CHANGED(txn, txn->mt_dbxs[i].md_name, i)) {
+                               if (TXN_DBI_CHANGED(txn, i)) {
                                        rc = MDB_BAD_DBI;
                                        goto fail;
                                }
@@ -4976,7 +4988,7 @@ mdb_page_search(MDB_cursor *mc, MDB_val *key, int flags)
                /* Make sure we're using an up-to-date root */
                if (*mc->mc_dbflag & DB_STALE) {
                                MDB_cursor mc2;
-                               if (TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbx->md_name, mc->mc_dbi))
+                               if (TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi))
                                        return MDB_BAD_DBI;
                                mdb_cursor_init(&mc2, mc->mc_txn, MAIN_DBI, NULL);
                                rc = mdb_page_search(&mc2, &mc->mc_dbx->md_name, 0);
@@ -5832,7 +5844,7 @@ mdb_cursor_touch(MDB_cursor *mc)
        if (mc->mc_dbi > MAIN_DBI && !(*mc->mc_dbflag & DB_DIRTY)) {
                MDB_cursor mc2;
                MDB_xcursor mcx;
-               if (TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbx->md_name, mc->mc_dbi))
+               if (TXN_DBI_CHANGED(mc->mc_txn, mc->mc_dbi))
                        return MDB_BAD_DBI;
                mdb_cursor_init(&mc2, mc->mc_txn, MAIN_DBI, &mcx);
                rc = mdb_page_search(&mc2, &mc->mc_dbx->md_name, MDB_PS_MODIFY);
@@ -8808,7 +8820,7 @@ int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *db
        MDB_dbi i;
        MDB_cursor mc;
        int rc, dbflag, exact;
-       unsigned int unused = 0;
+       unsigned int unused = 0, seq;
        size_t len;
 
        if (txn->mt_dbxs[FREE_DBI].md_cmp == NULL) {
@@ -8893,9 +8905,12 @@ int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *db
                txn->mt_dbxs[slot].md_name.mv_size = len;
                txn->mt_dbxs[slot].md_rel = NULL;
                txn->mt_dbflags[slot] = dbflag;
-               /* read txns don't track sequence numbers */
-               if (!(txn->mt_flags & MDB_TXN_RDONLY))
-                       txn->mt_dbiseqs[slot] = ++txn->mt_env->me_dbiseqs[slot];
+               /* txn-> and env-> are the same in read txns, use
+                * tmp variable to avoid undefined assignment
+                */
+               seq = ++txn->mt_env->me_dbiseqs[slot];
+               txn->mt_dbiseqs[slot] = seq;
+
                memcpy(&txn->mt_dbs[slot], data.mv_data, sizeof(MDB_db));
                *dbi = slot;
                mdb_default_cmp(txn, slot);
@@ -8930,11 +8945,14 @@ void mdb_dbi_close(MDB_env *env, MDB_dbi dbi)
        if (dbi <= MAIN_DBI || dbi >= env->me_maxdbs)
                return;
        ptr = env->me_dbxs[dbi].md_name.mv_data;
-       env->me_dbxs[dbi].md_name.mv_data = NULL;
-       env->me_dbxs[dbi].md_name.mv_size = 0;
-       env->me_dbflags[dbi] = 0;
-       env->me_dbiseqs[dbi]++;
-       free(ptr);
+       /* If there was no name, this was already closed */
+       if (ptr) {
+               env->me_dbxs[dbi].md_name.mv_data = NULL;
+               env->me_dbxs[dbi].md_name.mv_size = 0;
+               env->me_dbflags[dbi] = 0;
+               env->me_dbiseqs[dbi]++;
+               free(ptr);
+       }
 }
 
 int mdb_dbi_flags(MDB_txn *txn, MDB_dbi dbi, unsigned int *flags)
@@ -9044,7 +9062,7 @@ int mdb_drop(MDB_txn *txn, MDB_dbi dbi, int del)
        if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
                return EACCES;
 
-       if (dbi > MAIN_DBI && TXN_DBI_CHANGED(txn, txn->mt_dbxs[dbi].md_name, dbi))
+       if (dbi > MAIN_DBI && TXN_DBI_CHANGED(txn, dbi))
                return MDB_BAD_DBI;
 
        rc = mdb_cursor_open(txn, dbi, &mc);