1 files changed, 54 insertions, 28 deletions

diff --git a/mysys/mf_iocache.c b/mysys/mf_iocache.c
index 1a761fa5ed8..6e0a267165b 100644
--- a/mysys/mf_iocache.c
+++ b/mysys/mf_iocache.c
@@ -424,32 +424,62 @@ int _my_b_read(register IO_CACHE *info, byte *Buffer, uint Count)
   DBUG_RETURN(0);
 }
 
+
 #ifdef THREAD
-int init_io_cache_share(IO_CACHE *info, IO_CACHE_SHARE *s, uint num_threads)
+
+/* Initialzie multi-thread usage of the IO cache */
+
+void init_io_cache_share(IO_CACHE *info, IO_CACHE_SHARE *s, uint num_threads)
 {
   DBUG_ASSERT(info->type == READ_CACHE);
-  pthread_mutex_init(& s->mutex, MY_MUTEX_INIT_FAST);
-  pthread_cond_init (& s->cond, 0);
+  pthread_mutex_init(&s->mutex, MY_MUTEX_INIT_FAST);
+  pthread_cond_init(&s->cond, 0);
   s->count=num_threads;
   s->active=0; /* to catch errors */
   info->share=s;
   info->read_function=_my_b_read_r;
 }
 
-int remove_io_thread(IO_CACHE *info)
+void remove_io_thread(IO_CACHE *info)
 {
-  if (errno=pthread_mutex_lock(& info->share->mutex))
-    return -1;
+  pthread_mutex_lock(&info->share->mutex);
   if (! info->share->count--)
-    pthread_cond_signal(& info->share->cond);
-  pthread_mutex_unlock(& info->share->mutex);
+    pthread_cond_signal(&info->share->cond);
+  pthread_mutex_unlock(&info->share->mutex);
+}
+
+
+int lock_io_cache(IO_CACHE *info)
+{
+  pthread_mutex_lock(&info->share->mutex);
+  if (!info->share->count)
+    return 1;
+  info->share->count--;
+  pthread_cond_wait(&((info)->share->cond), &((info)->share->mutex));
+  if (!++info->share->count)
+    return 1;
+  pthread_mutex_unlock(&info->share->mutex);
   return 0;
 }
 
+void unlock_io_cache(IO_CACHE *info)
+{
+  pthread_cond_broadcast(&info->share->cond);
+  pthread_mutex_unlock(&info->share->mutex);
+}
+
+/*
+  Read from the io cache in a thread safe manner
+*/
+
+#define IO_ROUND_UP(X) (((X)+IO_SIZE-1) & ~(IO_SIZE-1))
+#define IO_ROUND_DN(X) ( (X)            & ~(IO_SIZE-1))
+
+
 int _my_b_read_r(register IO_CACHE *info, byte *Buffer, uint Count)
 {
   my_off_t pos_in_file;
-  int length,diff_length,read_len;
+  uint length,diff_length,read_len;
   DBUG_ENTER("_my_b_read_r");
 
   if ((read_len=(uint) (info->read_end-info->read_pos)))
@@ -459,26 +489,23 @@ int _my_b_read_r(register IO_CACHE *info, byte *Buffer, uint Count)
     Buffer+=read_len;
     Count-=read_len;
   }
-
-#define IO_ROUND_UP(X) (((X)+IO_SIZE-1) & ~(IO_SIZE-1))
-#define IO_ROUND_DN(X) ( (X)            & ~(IO_SIZE-1))
-
-  while (Count) {
-    int cnt, len;
+  while (Count)
+  {
+    uint cnt, len;
 
     pos_in_file= info->pos_in_file + (uint)(info->read_end - info->buffer);
-    diff_length= pos_in_file & (IO_SIZE-1);
+    diff_length= (uint) (pos_in_file & (IO_SIZE-1));
     length=IO_ROUND_UP(Count+diff_length)-diff_length;
-    length=(length <= info->read_length) ?
-                   length + IO_ROUND_DN(info->read_length - length) :
-                   length - IO_ROUND_UP(length - info->read_length) ;
+    length= ((length <= info->read_length) ?
+	     length + IO_ROUND_DN(info->read_length - length) :
+	     length - IO_ROUND_UP(length - info->read_length)) ;
     if (lock_io_cache(info))
     {
       info->share->active=info;
       if (info->seek_not_done)             /* File touched, do seek */
         VOID(my_seek(info->file,pos_in_file,MY_SEEK_SET,MYF(0)));
       len=my_read(info->file,info->buffer, length, info->myflags);
-      info->read_end=info->buffer + (len == -1 ? 0 : len);
+      info->read_end=info->buffer + (len == (uint) -1 ? 0 : len);
       info->error=(len == length ? 0 : len);
       info->pos_in_file=pos_in_file;
       unlock_io_cache(info);
@@ -494,7 +521,7 @@ int _my_b_read_r(register IO_CACHE *info, byte *Buffer, uint Count)
     info->seek_not_done=0;
     if (info->error)
     {
-      info->error=read_len;
+      info->error=(int) read_len;
       DBUG_RETURN(1);
     }
     cnt=(len > Count) ? Count : len;
@@ -508,6 +535,7 @@ int _my_b_read_r(register IO_CACHE *info, byte *Buffer, uint Count)
 }
 #endif
 
+
 /*
   Do sequential read from the SEQ_READ_APPEND cache
   we do this in three stages:
@@ -1072,13 +1100,11 @@ int end_io_cache(IO_CACHE *info)
 #ifdef THREAD
   /* simple protection against multi-close: destroying share first */
   if (info->share)
-    if (pthread_cond_destroy (& info->share->cond) |
-        pthread_mutex_destroy(& info->share->mutex))
-    {
-      DBUG_RETURN(1);
-    }
-    else
-      info->share=0;
+  {
+    pthread_cond_destroy(&info->share->cond);
+    pthread_mutex_destroy(&info->share->mutex);
+    info->share=0;
+  }
 #endif
 
   if ((pre_close=info->pre_close))