reorganize directories

[awesomized/libmemcached] / src / libmemcached / udp.cc

diff --git a/src/libmemcached/udp.cc b/src/libmemcached/udp.cc
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+++ b/src/libmemcached/udp.cc
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+/*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
+ * 
+ *  LibMemcached
+ *
+ *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
+ *  All rights reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions are
+ *  met:
+ *
+ *      * Redistributions of source code must retain the above copyright
+ *  notice, this list of conditions and the following disclaimer.
+ *
+ *      * Redistributions in binary form must reproduce the above
+ *  copyright notice, this list of conditions and the following disclaimer
+ *  in the documentation and/or other materials provided with the
+ *  distribution.
+ *
+ *      * The names of its contributors may not be used to endorse or
+ *  promote products derived from this software without specific prior
+ *  written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <libmemcached/common.h>
+
+/*
+ * The udp request id consists of two seperate sections
+ *   1) The thread id
+ *   2) The message number
+ * The thread id should only be set when the memcached_st struct is created
+ * and should not be changed.
+ *
+ * The message num is incremented for each new message we send, this function
+ * extracts the message number from message_id, increments it and then
+ * writes the new value back into the header
+ */
+void increment_udp_message_id(memcached_instance_st* ptr)
+{
+  struct udp_datagram_header_st *header= (struct udp_datagram_header_st *)ptr->write_buffer;
+  uint16_t cur_req= get_udp_datagram_request_id(header);
+  int msg_num= get_msg_num_from_request_id(cur_req);
+  int thread_id= get_thread_id_from_request_id(cur_req);
+
+  if (((++msg_num) & UDP_REQUEST_ID_THREAD_MASK) != 0)
+    msg_num= 0;
+
+  header->request_id= htons((uint16_t) (thread_id | msg_num));
+}
+
+bool memcached_io_init_udp_header(memcached_instance_st* ptr, const uint16_t thread_id)
+{
+  if (thread_id > UDP_REQUEST_ID_MAX_THREAD_ID)
+  {
+    return MEMCACHED_FAILURE;
+  }
+
+  struct udp_datagram_header_st *header= (struct udp_datagram_header_st *)ptr->write_buffer;
+  header->request_id= htons(uint16_t((generate_udp_request_thread_id(thread_id))));
+  header->num_datagrams= htons(1);
+  header->sequence_number= htons(0);
+
+  return MEMCACHED_SUCCESS;
+}