git.m6w6.name Git - awesomized/libmemcached/blob - libmemcached/protocol/common.h

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  Libmemcached library
   4  *
   5  *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
   6  *
   7  *  Redistribution and use in source and binary forms, with or without
   8  *  modification, are permitted provided that the following conditions are
   9  *  met:
  10  *
  11  *      * Redistributions of source code must retain the above copyright
  12  *  notice, this list of conditions and the following disclaimer.
  13  *
  14  *      * Redistributions in binary form must reproduce the above
  15  *  copyright notice, this list of conditions and the following disclaimer
  16  *  in the documentation and/or other materials provided with the
  17  *  distribution.
  18  *
  19  *      * The names of its contributors may not be used to endorse or
  20  *  promote products derived from this software without specific prior
  21  *  written permission.
  22  *
  23  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  26  *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  29  *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  30  *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  31  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  32  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  33  *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  *
  35  */
  36
  37 #pragma once
  38
  39 #include "config.h"
  40 #if !defined(__cplusplus)
  41 # include <stdbool.h>
  42 #endif
  43 #include <assert.h>
  44
  45 #include <libmemcached/visibility.h>
  46 #include <libmemcached/protocol_handler.h>
  47 #include <libmemcached/protocol/cache.h>
  48
  49 /*
  50  * I don't really need the following two functions as function pointers
  51  * in the instance handle, but I don't want to put them in the global
  52  * namespace for those linking statically (personally I don't like that,
  53  * but some people still do). If it ever shows up as a performance thing
  54  * I'll look into optimizing this ;-)
  55  */
  56 typedef bool (*drain_func)(memcached_protocol_client_st *client);
  57 typedef protocol_binary_response_status (*spool_func)(memcached_protocol_client_st *client,
  58                                                       const void *data,
  59                                                       size_t length);
  60
  61 /**
  62  * Definition of the per instance structure.
  63  */
  64 struct memcached_protocol_st {
  65   memcached_binary_protocol_callback_st *callback;
  66   memcached_protocol_recv_func recv;
  67   memcached_protocol_send_func send;
  68
  69   /*
  70    * I really don't need these as funciton pointers, but I don't want
  71    * to clutter the namespace if someone links statically.
  72    */
  73   drain_func drain;
  74   spool_func spool;
  75
  76   /*
  77    * To avoid keeping a buffer in each client all the time I have a
  78    * bigger buffer in the instance that I read to initially, and then
  79    * I try to parse and execute as much from the buffer. If I wasn't able
  80    * to process all data I'll keep that in a per-connection buffer until
  81    * the next time I can read from the socket.
  82    */
  83   uint8_t *input_buffer;
  84   size_t input_buffer_size;
  85
  86   bool pedantic;
  87   /* @todo use multiple sized buffers */
  88   cache_t *buffer_cache;
  89 };
  90
  91 struct chunk_st {
  92   /* Pointer to the data */
  93   char *data;
  94   /* The offset to the first byte into the buffer that is used */
  95   size_t offset;
  96   /* The offset into the buffer for the first free byte */
  97   size_t nbytes;
  98   /* The number of bytes in the buffer */
  99   size_t size;
 100   /* Pointer to the next buffer in the chain */
 101   struct chunk_st *next;
 102 };
 103
 104 #define CHUNK_BUFFERSIZE 2048
 105
 106 typedef memcached_protocol_event_t (*process_data)(struct memcached_protocol_client_st *client, ssize_t *length, void **endptr);
 107
 108 enum ascii_cmd {
 109   GET_CMD,
 110   GETS_CMD,
 111   SET_CMD,
 112   ADD_CMD,
 113   REPLACE_CMD,
 114   CAS_CMD,
 115   APPEND_CMD,
 116   PREPEND_CMD,
 117   DELETE_CMD,
 118   INCR_CMD,
 119   DECR_CMD,
 120   STATS_CMD,
 121   FLUSH_ALL_CMD,
 122   VERSION_CMD,
 123   QUIT_CMD,
 124   VERBOSITY_CMD,
 125   UNKNOWN_CMD
 126 };
 127
 128 struct memcached_protocol_client_st {
 129   memcached_protocol_st *root;
 130   memcached_socket_t sock;
 131   int error;
 132
 133   /* Linked list of data to send */
 134   struct chunk_st *output;
 135   struct chunk_st *output_tail;
 136
 137   /*
 138    * While we process input data, this is where we spool incomplete commands
 139    * if we need to receive more data....
 140    * @todo use the buffercace
 141    */
 142   uint8_t *input_buffer;
 143   size_t input_buffer_size;
 144   size_t input_buffer_offset;
 145
 146   /* The callback to the protocol handler to use (ascii or binary) */
 147   process_data work;
 148
 149   /*
 150    * Should the spool data discard the data to send or not? (aka noreply in
 151    * the ascii protocol..
 152    */
 153   bool mute;
 154
 155   /* Members used by the binary protocol */
 156   protocol_binary_request_header *current_command;
 157
 158   /* Members used by the ascii protocol */
 159   enum ascii_cmd ascii_command;
 160 };
 161
 162 #include "ascii_handler.h"
 163 #include "binary_handler.h"