Bug #18480 Windows file rename problems in archive storage engine

The problem was that the optimize code was not closing both the reader and writer streams before attempting
to rename the file.  This will not work on Windows where all file handles have to be closed before the
file can be renamed, moved, or deleted.  The fix was to move the close calls before the rename.
We return the error code from my_rename in case of failure but we attempt to reopen the writers and readers
even in the case of failure so that the table can still be usable.

storage/archive/ha_archive.cc

@@ -1239,7 +1239,7 @@ int ha_archive::repair(THD* thd, HA_CHECK_OPT* check_opt)
 int ha_archive::optimize(THD* thd, HA_CHECK_OPT* check_opt)
 {
   DBUG_ENTER("ha_archive::optimize");
-  int rc;
+  int rc= 0;
   azio_stream writer;
   char writer_filename[FN_REFLEN];
 
@@ -1342,7 +1342,20 @@ int ha_archive::optimize(THD* thd, HA_CHECK_OPT* check_opt)
   azclose(&writer);
   share->dirty= FALSE;
   share->forced_flushes= 0;
+  
+  // now we close both our writer and our reader for the rename
   azclose(&(share->archive_write));
+  azclose(&archive);
+
+  // make the file we just wrote be our data file
+  rc = my_rename(writer_filename,share->data_file_name,MYF(0));
+
+  /*
+    now open the shared writer back up
+    we don't check rc here because we want to open the file back up even
+    if the optimize failed but we will return rc below so that we will
+    know it failed.
+  */
   DBUG_PRINT("info", ("Reopening archive data file"));
   if (!(azopen(&(share->archive_write), share->data_file_name, 
                O_WRONLY|O_APPEND|O_BINARY)))
@@ -1352,21 +1365,15 @@ int ha_archive::optimize(THD* thd, HA_CHECK_OPT* check_opt)
     goto error;
   }
 
-  my_rename(writer_filename,share->data_file_name,MYF(0));
-
   /*
     Now we need to reopen our read descriptor since it has changed.
   */
-  azclose(&archive);
   if (!(azopen(&archive, share->data_file_name, O_RDONLY|O_BINARY)))
   {
     rc= HA_ERR_CRASHED_ON_USAGE;
     goto error;
   }
 
-
-  DBUG_RETURN(0); 
-
 error:
   azclose(&writer);