Added HANDLER support for MEMORY tables

Added key and file version numbers to MEMORY tables so that we can detect if someone has changed them between HANDLER calls.


mysql-test/suite/handler/aria.result:
  Fixed result after test changes
mysql-test/suite/handler/handler.inc:
  Changed test to use combined key to ensure rows are returned in a pre-determinated order.
mysql-test/suite/handler/heap.result:
  New result
mysql-test/suite/handler/heap.test:
  Added test for HANDLER + HEAP
mysql-test/suite/handler/innodb.result:
  Fixed result after test changes
mysql-test/suite/handler/myisam.result:
  Fixed result after test changes
sql/sql_handler.cc:
  Fixed wrong parameter to ha_index_next_same()
storage/heap/ha_heap.cc:
  Abort key scan if table has changed.
  Abort table scan if table has been recreated.
storage/heap/ha_heap.h:
  Added support for HANDLER
storage/heap/hp_clear.c:
  Increase version number so that we can notice changes if using HANDLER
storage/heap/hp_delete.c:
  Increase key data version number on key changes.
storage/heap/hp_rfirst.c:
  Remember version of key data
  Give error if using read-first on hash key.
storage/heap/hp_rkey.c:
  Remember version of key data
storage/heap/hp_rlast.c:
  Remember version of key data
  Give error if using read-last on hash key.
storage/heap/hp_rnext.c:
  Fixed that we get next key from last search.
storage/heap/hp_rprev.c:
  Fixed that we get previous key from last search.
storage/heap/hp_scan.c:
  Remember version of key and file data
storage/heap/hp_update.c:
  Increase key data version number on key changes.
storage/heap/hp_write.c:
  Increase key data version number on key changes.

12 files changed, 37 insertions, 16 deletions

diff --git a/storage/heap/ha_heap.cc b/storage/heap/ha_heap.cc
index 2d2c23a2ed6..6bb6936de9d 100644
--- a/storage/heap/ha_heap.cc
+++ b/storage/heap/ha_heap.cc
@@ -183,6 +183,19 @@ void ha_heap::set_keys_for_scanning(void)
 }
 
 
+int ha_heap::can_continue_handler_scan()
+{
+  int error= 0;
+  if ((file->key_version != file->s->key_version && inited == INDEX) ||
+      (file->file_version != file->s->file_version && inited == RND))
+  {
+    /* Data changed, not safe to do index or rnd scan */
+    error= HA_ERR_RECORD_CHANGED;
+  }
+  return error;
+}
+
+
 void ha_heap::update_key_stats()
 {
   for (uint i= 0; i < table->s->keys; i++)
diff --git a/storage/heap/ha_heap.h b/storage/heap/ha_heap.h
index 22722129f4c..49aa91a6caa 100644
--- a/storage/heap/ha_heap.h
+++ b/storage/heap/ha_heap.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2000-2006 MySQL AB
+/* Copyright (C) 2000-2006 MySQL AB, 2009-2011 Monty Program Ab
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -52,6 +52,7 @@ public:
   {
     return (HA_FAST_KEY_READ | HA_NO_BLOBS | HA_NULL_IN_KEY |
             HA_BINLOG_ROW_CAPABLE | HA_BINLOG_STMT_CAPABLE |
+            HA_CAN_SQL_HANDLER |
             HA_REC_NOT_IN_SEQ | HA_CAN_INSERT_DELAYED | HA_NO_TRANSACTIONS |
             HA_HAS_RECORDS | HA_STATS_RECORDS_IS_EXACT);
   }
@@ -93,6 +94,7 @@ public:
   int rnd_next(uchar *buf);
   int rnd_pos(uchar * buf, uchar *pos);
   void position(const uchar *record);
+  int can_continue_handler_scan();
   int info(uint);
   int extra(enum ha_extra_function operation);
   int reset();
diff --git a/storage/heap/hp_clear.c b/storage/heap/hp_clear.c
index babfcbd6f41..b999f1ff5e8 100644
--- a/storage/heap/hp_clear.c
+++ b/storage/heap/hp_clear.c
@@ -40,6 +40,8 @@ void hp_clear(HP_SHARE *info)
   info->blength=1;
   info->changed=0;
   info->del_link=0;
+  info->key_version++;
+  info->file_version++;
   DBUG_VOID_RETURN;
 }
 
diff --git a/storage/heap/hp_delete.c b/storage/heap/hp_delete.c
index 9e9e28da335..1af9cf26f8c 100644
--- a/storage/heap/hp_delete.c
+++ b/storage/heap/hp_delete.c
@@ -47,6 +47,7 @@ int heap_delete(HP_INFO *info, const uchar *record)
   share->del_link=pos;
   pos[share->reclength]=0;		/* Record deleted */
   share->deleted++;
+  share->key_version++;
   info->current_hash_ptr=0;
 #if !defined(DBUG_OFF) && defined(EXTRA_HEAP_DEBUG)
   DBUG_EXECUTE("check_heap",heap_check_heap(info, 0););
diff --git a/storage/heap/hp_rfirst.c b/storage/heap/hp_rfirst.c
index d0d2ec9b506..8e562983b02 100644
--- a/storage/heap/hp_rfirst.c
+++ b/storage/heap/hp_rfirst.c
@@ -24,6 +24,8 @@ int heap_rfirst(HP_INFO *info, uchar *record, int inx)
   
   DBUG_ENTER("heap_rfirst");
   info->lastinx= inx;
+  info->key_version= info->s->key_version;
+
   if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
   {
     uchar *pos;
@@ -57,15 +59,8 @@ int heap_rfirst(HP_INFO *info, uchar *record, int inx)
   }
   else
   {
-    if (!(info->s->records))
-    {
-      my_errno=HA_ERR_END_OF_FILE;
-      DBUG_RETURN(my_errno);
-    }
-    DBUG_ASSERT(0); /* TODO fix it */
-    info->current_record=0;
-    info->current_hash_ptr=0;
-    info->update=HA_STATE_PREV_FOUND;
-    DBUG_RETURN(heap_rnext(info,record));
+    /* We can't scan a non existing key value with hash index */
+    my_errno= HA_ERR_WRONG_COMMAND;
+    DBUG_RETURN(my_errno);
   }
 }
diff --git a/storage/heap/hp_rkey.c b/storage/heap/hp_rkey.c
index 27d1114770e..c2edf63f6f2 100644
--- a/storage/heap/hp_rkey.c
+++ b/storage/heap/hp_rkey.c
@@ -30,6 +30,7 @@ int heap_rkey(HP_INFO *info, uchar *record, int inx, const uchar *key,
   }
   info->lastinx= inx;
   info->current_record= (ulong) ~0L;		/* For heap_rrnd() */
+  info->key_version= info->s->key_version;
 
   if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
   {
diff --git a/storage/heap/hp_rlast.c b/storage/heap/hp_rlast.c
index 45ad7c21f49..0710401e5a5 100644
--- a/storage/heap/hp_rlast.c
+++ b/storage/heap/hp_rlast.c
@@ -25,6 +25,7 @@ int heap_rlast(HP_INFO *info, uchar *record, int inx)
 
   DBUG_ENTER("heap_rlast");
   info->lastinx= inx;
+  info->key_version= info->s->key_version;
   if (keyinfo->algorithm == HA_KEY_ALG_BTREE)
   {
     uchar *pos;
@@ -47,9 +48,8 @@ int heap_rlast(HP_INFO *info, uchar *record, int inx)
   }
   else
   {
-    info->current_ptr=0;
-    info->current_hash_ptr=0;
-    info->update=HA_STATE_NEXT_FOUND;
-    DBUG_RETURN(heap_rprev(info,record));
+    /* We can't scan a non existing key value with hash index */
+    my_errno= HA_ERR_WRONG_COMMAND;
+    DBUG_RETURN(my_errno);
   }
 }
diff --git a/storage/heap/hp_rnext.c b/storage/heap/hp_rnext.c
index 3d715f4e6d3..7a654850e0e 100644
--- a/storage/heap/hp_rnext.c
+++ b/storage/heap/hp_rnext.c
@@ -70,6 +70,7 @@ int heap_rnext(HP_INFO *info, uchar *record)
       custom_arg.keyseg = keyinfo->seg;
       custom_arg.key_length = info->lastkey_len;
       custom_arg.search_flag = SEARCH_SAME | SEARCH_FIND;
+      info->last_find_flag= HA_READ_KEY_OR_NEXT;
       pos = tree_search_key(&keyinfo->rb_tree, info->lastkey, info->parents, 
                            &info->last_pos, info->last_find_flag, &custom_arg);
     }
diff --git a/storage/heap/hp_rprev.c b/storage/heap/hp_rprev.c
index 63bfffffba9..1d71c20eef4 100644
--- a/storage/heap/hp_rprev.c
+++ b/storage/heap/hp_rprev.c
@@ -41,6 +41,7 @@ int heap_rprev(HP_INFO *info, uchar *record)
       custom_arg.keyseg = keyinfo->seg;
       custom_arg.key_length = keyinfo->length;
       custom_arg.search_flag = SEARCH_SAME;
+      info->last_find_flag= HA_READ_KEY_OR_PREV;
       pos = tree_search_key(&keyinfo->rb_tree, info->lastkey, info->parents, 
                            &info->last_pos, info->last_find_flag, &custom_arg);
     }
diff --git a/storage/heap/hp_scan.c b/storage/heap/hp_scan.c
index e8913e92c86..397dd8b54d4 100644
--- a/storage/heap/hp_scan.c
+++ b/storage/heap/hp_scan.c
@@ -31,6 +31,8 @@ int heap_scan_init(register HP_INFO *info)
   info->current_record= (ulong) ~0L;		/* No current record */
   info->update=0;
   info->next_block=0;
+  info->key_version= info->s->key_version;
+  info->file_version= info->s->file_version;
   DBUG_RETURN(0);
 }
 
diff --git a/storage/heap/hp_update.c b/storage/heap/hp_update.c
index 7f469af3c96..ab831382325 100644
--- a/storage/heap/hp_update.c
+++ b/storage/heap/hp_update.c
@@ -21,7 +21,7 @@ int heap_update(HP_INFO *info, const uchar *old, const uchar *heap_new)
 {
   HP_KEYDEF *keydef, *end, *p_lastinx;
   uchar *pos;
-  my_bool auto_key_changed= 0;
+  my_bool auto_key_changed= 0, key_changed= 0;
   HP_SHARE *share= info->s;
   DBUG_ENTER("heap_update");
 
@@ -54,6 +54,8 @@ int heap_update(HP_INFO *info, const uchar *old, const uchar *heap_new)
 #endif
   if (auto_key_changed)
     heap_update_auto_increment(info, heap_new);
+  if (key_changed)
+    share->key_version++;
   DBUG_RETURN(0);
 
  err:
diff --git a/storage/heap/hp_write.c b/storage/heap/hp_write.c
index 4e8fa7e3580..bf27503de9b 100644
--- a/storage/heap/hp_write.c
+++ b/storage/heap/hp_write.c
@@ -56,6 +56,7 @@ int heap_write(HP_INFO *info, const uchar *record)
   pos[share->reclength]=1;		/* Mark record as not deleted */
   if (++share->records == share->blength)
     share->blength+= share->blength;
+  info->s->key_version++;
   info->current_ptr=pos;
   info->current_hash_ptr=0;
   info->update|=HA_STATE_AKTIV;