changed to use IO_CACHE instead of FILE

5 files changed, 15 insertions, 4 deletions

diff --git a/myisam/mi_create.c b/myisam/mi_create.c
index 048bbb427a2..89bdcdf3fbc 100644
--- a/myisam/mi_create.c
+++ b/myisam/mi_create.c
@@ -417,6 +417,7 @@ int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
   share.state.dellink = HA_OFFSET_ERROR;
   share.state.process=	(ulong) getpid();
   share.state.unique=	(ulong) 0;
+  share.state.update_count=(ulong) 0;
   share.state.version=	(ulong) time((time_t*) 0);
   share.state.sortkey=  (ushort) ~0;
   share.state.auto_increment=ci->auto_increment;
diff --git a/myisam/mi_locking.c b/myisam/mi_locking.c
index 4797584627a..45bb2cd7164 100644
--- a/myisam/mi_locking.c
+++ b/myisam/mi_locking.c
@@ -70,6 +70,7 @@ int mi_lock_database(MI_INFO *info, int lock_type)
 	{
 	  share->state.process= share->last_process=share->this_process;
 	  share->state.unique=   info->last_unique=  info->this_unique;
+	  share->state.update_count= info->last_loop= ++info->this_loop;
 	  if (mi_state_info_write(share->kfile, &share->state, 1))
 	    error=my_errno;
 	  share->changed=0;
@@ -346,6 +347,7 @@ int _mi_writeinfo(register MI_INFO *info, uint operation)
     {					/* Two threads can't be here */
       share->state.process= share->last_process=   share->this_process;
       share->state.unique=  info->last_unique=	   info->this_unique;
+      share->state.update_count= info->last_loop= ++info->this_loop;
       if ((error=mi_state_info_write(share->kfile, &share->state, 1)))
 	olderror=my_errno;
 #ifdef __WIN__
@@ -377,12 +379,14 @@ int _mi_test_if_changed(register MI_INFO *info)
 {
   MYISAM_SHARE *share=info->s;
   if (share->state.process != share->last_process ||
-      share->state.unique  != info->last_unique)
+      share->state.unique  != info->last_unique ||
+      share->state.update_count != info->last_loop)
   {						/* Keyfile has changed */
     if (share->state.process != share->this_process)
       VOID(flush_key_blocks(share->kfile,FLUSH_RELEASE));
     share->last_process=share->state.process;
     info->last_unique=	share->state.unique;
+    info->last_loop=	share->state.update_count;
     info->update|=	HA_STATE_WRITTEN;	/* Must use file on next */
     info->data_changed= 1;			/* For mi_is_changed */
     return 1;
diff --git a/myisam/mi_open.c b/myisam/mi_open.c
index aeaf9e5e9b4..c29a4a843ca 100644
--- a/myisam/mi_open.c
+++ b/myisam/mi_open.c
@@ -445,8 +445,9 @@ MI_INFO *mi_open(const char *name, int mode, uint open_flags)
   info.this_unique= (ulong) info.dfile; /* Uniq number in process */
   if (share->data_file_type == COMPRESSED_RECORD)
     info.this_unique= share->state.unique;
-  info.this_loop=0;			/* Update counter */
+  info.this_loop=0;				/* Update counter */
   info.last_unique= share->state.unique;
+  info.last_loop=   share->state.update_count;
   if (mode == O_RDONLY)
     share->options|=HA_OPTION_READ_ONLY_DATA;
   info.lock_type=F_UNLCK;
@@ -669,7 +670,7 @@ uint mi_state_info_write(File file, MI_STATE_INFO *state, uint pWrite)
   mi_int4store(ptr,state->process);		ptr +=4;
   mi_int4store(ptr,state->unique);		ptr +=4;
   mi_int4store(ptr,state->status);		ptr +=4;
-  *ptr++=0; *ptr++=0;  *ptr++=0; *ptr++=0;	/* extra */
+  mi_int4store(ptr,state->update_count);	ptr +=4;
 
   ptr+=state->state_diff_length;
 
diff --git a/myisam/mi_search.c b/myisam/mi_search.c
index eead2a84c29..3ffc348ca5c 100644
--- a/myisam/mi_search.c
+++ b/myisam/mi_search.c
@@ -1214,7 +1214,11 @@ int _mi_search_next(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   DBUG_EXECUTE("key",_mi_print_key(DBUG_FILE,keyinfo->seg,key,key_length););
 
   /* Force full read if we are at last key or if we are not on a leaf
-     and the key tree has changed since we used it last time */
+     and the key tree has changed since we used it last time
+     Note that even if the key tree has changed since last read, we can use
+     the last read data from the leaf if we haven't used the buffer for
+     something else.
+  */
 
   if (((nextflag & SEARCH_BIGGER) && info->int_keypos >= info->int_maxpos) ||
       info->page_changed ||
diff --git a/myisam/myisamdef.h b/myisam/myisamdef.h
index a65694dbd94..ad153d58b70 100644
--- a/myisam/myisamdef.h
+++ b/myisam/myisamdef.h
@@ -64,6 +64,7 @@ typedef struct st_mi_state_info
   ulonglong auto_increment;
   ulong process;			/* process that updated table last */
   ulong unique;				/* Unique number for this process */
+  ulong update_count;			/* Updated for each write lock */
   ulong status;
   my_off_t *key_root;			/* Start of key trees */
   my_off_t *key_del;			/* delete links for trees */