git.m6w6.name Git - m6w6/libmemcached/blob - libmemcachedprotocol/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 <libmemcachedprotocol-0.0/handler.h>
  46 #include <libmemcachedprotocol/cache.h>
  47 #include <libmemcached/byteorder.h>
  48 #include <libmemcached/close_socket.hpp>
  49
  50 /*
  51  * I don't really need the following two functions as function pointers
  52  * in the instance handle, but I don't want to put them in the global
  53  * namespace for those linking statically (personally I don't like that,
  54  * but some people still do). If it ever shows up as a performance thing
  55  * I'll look into optimizing this ;-)
  56  */
  57 typedef bool (*drain_func)(memcached_protocol_client_st *client);
  58 typedef protocol_binary_response_status (*spool_func)(memcached_protocol_client_st *client,
  59                                                       const void *data,
  60                                                       size_t length);
  61
  62 /**
  63  * Definition of the per instance structure.
  64  */
  65 struct memcached_protocol_st {
  66   memcached_binary_protocol_callback_st *callback;
  67   memcached_protocol_recv_func recv;
  68   memcached_protocol_send_func send;
  69
  70   /*
  71    * I really don't need these as funciton pointers, but I don't want
  72    * to clutter the namespace if someone links statically.
  73    */
  74   drain_func drain;
  75   spool_func spool;
  76
  77   /*
  78    * To avoid keeping a buffer in each client all the time I have a
  79    * bigger buffer in the instance that I read to initially, and then
  80    * I try to parse and execute as much from the buffer. If I wasn't able
  81    * to process all data I'll keep that in a per-connection buffer until
  82    * the next time I can read from the socket.
  83    */
  84   uint8_t *input_buffer;
  85   size_t input_buffer_size;
  86
  87   bool pedantic;
  88   /* @todo use multiple sized buffers */
  89   cache_t *buffer_cache;
  90 };
  91
  92 struct chunk_st {
  93   /* Pointer to the data */
  94   char *data;
  95   /* The offset to the first byte into the buffer that is used */
  96   size_t offset;
  97   /* The offset into the buffer for the first free byte */
  98   size_t nbytes;
  99   /* The number of bytes in the buffer */
 100   size_t size;
 101   /* Pointer to the next buffer in the chain */
 102   struct chunk_st *next;
 103 };
 104
 105 #define CHUNK_BUFFERSIZE 2048
 106
 107 typedef memcached_protocol_event_t (*process_data)(struct memcached_protocol_client_st *client, ssize_t *length, void **endptr);
 108
 109 enum ascii_cmd {
 110   GET_CMD,
 111   GETS_CMD,
 112   SET_CMD,
 113   ADD_CMD,
 114   REPLACE_CMD,
 115   CAS_CMD,
 116   APPEND_CMD,
 117   PREPEND_CMD,
 118   DELETE_CMD,
 119   INCR_CMD,
 120   DECR_CMD,
 121   STATS_CMD,
 122   FLUSH_ALL_CMD,
 123   VERSION_CMD,
 124   QUIT_CMD,
 125   VERBOSITY_CMD,
 126   UNKNOWN_CMD
 127 };
 128
 129 struct memcached_protocol_client_st {
 130   memcached_protocol_st *root;
 131   memcached_socket_t sock;
 132   int error;
 133
 134   /* Linked list of data to send */
 135   struct chunk_st *output;
 136   struct chunk_st *output_tail;
 137
 138   /*
 139    * While we process input data, this is where we spool incomplete commands
 140    * if we need to receive more data....
 141    * @todo use the buffercace
 142    */
 143   uint8_t *input_buffer;
 144   size_t input_buffer_size;
 145   size_t input_buffer_offset;
 146
 147   /* The callback to the protocol handler to use (ascii or binary) */
 148   process_data work;
 149
 150   /*
 151    * Should the spool data discard the data to send or not? (aka noreply in
 152    * the ascii protocol..
 153    */
 154   bool mute;
 155
 156   /* Members used by the binary protocol */
 157   protocol_binary_request_header *current_command;
 158
 159   /* Members used by the ascii protocol */
 160   enum ascii_cmd ascii_command;
 161 };
 162
 163 #include "ascii_handler.h"
 164 #include "binary_handler.h"