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+/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+
+ 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
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+/**
+ @file
+
+ @details
+ Caching of files with only does (sequential) read or writes of fixed-
+ length records. A read isn't allowed to go over file-length. A read is ok
+ if it ends at file-length and next read can try to read after file-length
+ (and get a EOF-error).
+ Possibly use of asyncronic io.
+ macros for read and writes for faster io.
+ Used instead of FILE when reading or writing whole files.
+ This will make mf_rec_cache obsolete.
+ One can change info->pos_in_file to a higher value to skip bytes in file if
+ also info->read_pos is set to info->read_end.
+ If called through open_cached_file(), then the temporary file will
+ only be created if a write exeeds the file buffer or if one calls
+ flush_io_cache().
+*/
+
+#include "mariadb.h"
+#include "sql_priv.h"
+#include "sql_class.h" // THD
+#ifdef HAVE_REPLICATION
+
+extern "C" {
+
+/**
+ Read buffered from the net.
+
+ @retval
+ 1 if can't read requested characters
+ @retval
+ 0 if record read
+*/
+
+
+int _my_b_net_read(IO_CACHE *info, uchar *Buffer, size_t)
+{
+ ulong read_length;
+ NET *net= &(current_thd)->net;
+ DBUG_ENTER("_my_b_net_read");
+
+ if (!info->end_of_file)
+ DBUG_RETURN(1); /* because my_b_get (no _) takes 1 byte at a time */
+ read_length= my_net_read_packet(net, 0);
+ if (unlikely(read_length == packet_error))
+ {
+ info->error= -1;
+ DBUG_RETURN(1);
+ }
+ if (unlikely(read_length == 0))
+ {
+ info->end_of_file= 0; /* End of file from client */
+ DBUG_RETURN(1);
+ }
+ /* to set up stuff for my_b_get (no _) */
+ info->read_end = (info->read_pos = (uchar*) net->read_pos) + read_length;
+ Buffer[0] = info->read_pos[0]; /* length is always 1 */
+
+ /*
+ info->request_pos is used by log_loaded_block() to know the size
+ of the current block.
+ info->pos_in_file is used by log_loaded_block() too.
+ */
+ info->pos_in_file+= read_length;
+ info->request_pos=info->read_pos;
+
+ info->read_pos++;
+
+ DBUG_RETURN(0);
+}
+
+} /* extern "C" */
+
+#elif defined(_WIN32)
+
+// Remove linker warning 4221 about empty file
+namespace { char dummy; };
+
+#endif /* HAVE_REPLICATION */
+
+