More subdb stuff, add cursor_last()

diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index 87d531964f8df99b541a9cc4bf2e9ac00d512fa7..d0e28d3215c25ac32cdeeff058cec57f7c1de207 100644 (file)
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -223,13 +223,12 @@ typedef struct MDB_db {
 } MDB_db;
 
 typedef struct MDB_dbx {
-       char            *md_name;
+       MDB_val         md_name;
        MDB_cmp_func    *md_cmp;                /* user compare function */
        MDB_cmp_func    *md_dcmp;               /* user dupsort function */
        MDB_rel_func    *md_rel;                /* user relocate function */
        MDB_db          *md_db;
        MDB_page        *md_page;
-       unsigned int    md_ki;                  /* cursor index on parent page */
 } MDB_dbx;
 
 struct MDB_txn {
@@ -331,6 +330,8 @@ static int           mdb_cursor_set(MDB_cursor *cursor,
                            MDB_val *key, MDB_val *data, int *exactp);
 static int              mdb_cursor_first(MDB_cursor *cursor,
                            MDB_val *key, MDB_val *data);
+static int              mdb_cursor_last(MDB_cursor *cursor,
+                           MDB_val *key, MDB_val *data);
 
 static size_t           mdb_leaf_size(MDB_env *env, MDB_val *key,
                            MDB_val *data);
@@ -1372,7 +1373,10 @@ mdb_search_page_root(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
 
                if (key == NULL)        /* Initialize cursor to first page. */
                        i = 0;
-               else {
+               else if (key->mv_size > MAXKEYSIZE && key->mv_data == NULL) {
+                                                       /* cursor to last page */
+                       i = NUMKEYS(mp)-1;
+               } else {
                        int      exact;
                        node = mdb_search_node(txn, dbi, mp, key, &exact, &i);
                        if (node == NULL)
@@ -1458,12 +1462,22 @@ mdb_search_page(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
 
        DPRINTF("root page has flags 0x%X", mpp->mp_page->mp_flags);
 
-       if (modify && !F_ISSET(mpp->mp_page->mp_flags, P_DIRTY)) {
-               mpp->mp_parent = NULL;
-               mpp->mp_pi = 0;
-               if ((rc = mdb_touch(txn, mpp)))
-                       return rc;
-               txn->mt_dbxs[dbi].md_db->md_root = mpp->mp_page->mp_pgno;
+       if (modify) {
+               /* For sub-databases, update main root first */
+               if (dbi && !F_ISSET(txn->mt_dbxs[dbi].md_page->mp_flags, P_DIRTY)) {
+                       MDB_pageparent mp2;
+                       rc = mdb_search_page(txn, 0, &txn->mt_dbxs[dbi].md_name,
+                               NULL, 1, &mp2);
+                       if (rc)
+                               return rc;
+               }
+               if (!F_ISSET(mpp->mp_page->mp_flags, P_DIRTY)) {
+                       mpp->mp_parent = NULL;
+                       mpp->mp_pi = 0;
+                       if ((rc = mdb_touch(txn, mpp)))
+                               return rc;
+                       txn->mt_dbxs[dbi].md_db->md_root = mpp->mp_page->mp_pgno;
+               }
        }
 
        return mdb_search_page_root(txn, dbi, key, cursor, modify, mpp);
@@ -1698,6 +1712,32 @@ mdb_cursor_first(MDB_cursor *cursor, MDB_val *key, MDB_val *data)
        return mdb_set_key(leaf, key);
 }
 
+static int
+mdb_cursor_last(MDB_cursor *cursor, MDB_val *key, MDB_val *data)
+{
+       int              rc;
+       MDB_pageparent  mpp;
+       MDB_node        *leaf;
+       MDB_val lkey;
+
+       lkey.mv_size = MAXKEYSIZE+1;
+       lkey.mv_data = NULL;
+
+       rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, &lkey, cursor, 0, &mpp);
+       if (rc != MDB_SUCCESS)
+               return rc;
+       assert(IS_LEAF(mpp.mp_page));
+
+       leaf = NODEPTR(mpp.mp_page, NUMKEYS(mpp.mp_page)-1);
+       cursor->mc_initialized = 1;
+       cursor->mc_eof = 1;
+
+       if (data && (rc = mdb_read_data(cursor->mc_txn->mt_env, leaf, data)) != MDB_SUCCESS)
+               return rc;
+
+       return mdb_set_key(leaf, key);
+}
+
 int
 mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
     MDB_cursor_op op)
@@ -1730,6 +1770,11 @@ mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
                        cursor_pop_page(cursor);
                rc = mdb_cursor_first(cursor, key, data);
                break;
+       case MDB_LAST:
+               while (CURSOR_TOP(cursor) != NULL)
+                       cursor_pop_page(cursor);
+               rc = mdb_cursor_last(cursor, key, data);
+               break;
        default:
                DPRINTF("unhandled/unimplemented cursor operation %u", op);
                rc = EINVAL;
@@ -2561,6 +2606,7 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
        MDB_val key, data;
        MDB_dbi i;
        int rc;
+       size_t len;
 
        /* main DB? */
        if (!name) {
@@ -2569,15 +2615,17 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
        }
 
        /* Is the DB already open? */
+       len = strlen(name);
        for (i=0; i<txn->mt_numdbs; i++) {
-               if (!strcmp(name, txn->mt_dbxs[i].md_name)) {
+               if (len == txn->mt_dbxs[i].md_name.mv_size &&
+                       !strcmp(name, txn->mt_dbxs[i].md_name.mv_data)) {
                        *dbi = i;
                        return MDB_SUCCESS;
                }
        }
 
        /* Find the DB info */
-       key.mv_size = strlen(name);
+       key.mv_size = len;
        key.mv_data = (void *)name;
        rc = mdb_get(txn, 0, &key, &data);
 
@@ -2606,7 +2654,8 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
                                return ENOMEM;
                        txn->mt_dbxs = p1;
                }
-               txn->mt_dbxs[txn->mt_numdbs].md_name = strdup(name);
+               txn->mt_dbxs[txn->mt_numdbs].md_name.mv_data = strdup(name);
+               txn->mt_dbxs[txn->mt_numdbs].md_name.mv_size = len;
                txn->mt_dbxs[txn->mt_numdbs].md_cmp = NULL;
                txn->mt_dbxs[txn->mt_numdbs].md_dcmp = NULL;
                txn->mt_dbxs[txn->mt_numdbs].md_rel = NULL;
@@ -2637,6 +2686,7 @@ void mdb_close(MDB_txn *txn, MDB_dbi dbi)
 {
        if (dbi >= txn->mt_numdbs)
                return;
-       free(txn->mt_dbxs[dbi].md_name);
-       txn->mt_dbxs[dbi].md_name = NULL;
+       free(txn->mt_dbxs[dbi].md_name.mv_data);
+       txn->mt_dbxs[dbi].md_name.mv_data = NULL;
+       txn->mt_dbxs[dbi].md_name.mv_size = 0;
 }