git.m6w6.name Git - awesomized/libmemcached/blob - clients/ms_conn.h

   1 /*
   2  * File:   ms_conn.h
   3  * Author: Mingqiang Zhuang
   4  *
   5  * Created on February 10, 2009
   6  *
   7  * (c) Copyright 2009, Schooner Information Technology, Inc.
   8  * http://www.schoonerinfotech.com/
   9  *
  10  */
  11 #ifndef MS_CONN_H
  12 #define MS_CONN_H
  13
  14 #include <sys/socket.h>
  15 #include <netinet/in.h>
  16 #include <event.h>
  17 #include <netdb.h>
  18
  19 #include "ms_task.h"
  20 #include <libmemcached/memcached/protocol_binary.h>
  21
  22 #ifdef __cplusplus
  23 extern "C" {
  24 #endif
  25
  26 #define DATA_BUFFER_SIZE             (1024 * 1024 + 2048) /* read buffer, 1M + 2k, enough for the max value(1M) */
  27 #define WRITE_BUFFER_SIZE            (32 * 1024)          /* write buffer, 32k */
  28 #define UDP_DATA_BUFFER_SIZE         (1 * 1024 * 1024)    /* read buffer for UDP, 1M */
  29 #define UDP_MAX_PAYLOAD_SIZE         1400                 /* server limit UDP payload size */
  30 #define UDP_MAX_SEND_PAYLOAD_SIZE    1400                 /* mtu size is 1500 */
  31 #define UDP_HEADER_SIZE              8                    /* UDP header size */
  32 #define MAX_SENDBUF_SIZE             (256 * 1024 * 1024)  /* Maximum socket buffer size */
  33 #define SOCK_WAIT_TIMEOUT            30                   /* maximum waiting time of UDP, 30s */
  34 #define MAX_UDP_PACKET               (1 << 16)            /* maximum UDP packets, 65536 */
  35
  36 /* Initial size of the sendmsg() scatter/gather array. */
  37 #define IOV_LIST_INITIAL             400
  38
  39 /* Initial number of sendmsg() argument structures to allocate. */
  40 #define MSG_LIST_INITIAL             10
  41
  42 /* High water marks for buffer shrinking */
  43 #define READ_BUFFER_HIGHWAT          (2 * DATA_BUFFER_SIZE)
  44 #define UDP_DATA_BUFFER_HIGHWAT      (4 * UDP_DATA_BUFFER_SIZE)
  45 #define IOV_LIST_HIGHWAT             600
  46 #define MSG_LIST_HIGHWAT             100
  47
  48 /* parse udp header */
  49 #define HEADER_TO_REQID(ptr)      ((uint16_t)*ptr * 256 \
  50                                    + (uint16_t)*(ptr + 1))
  51 #define HEADER_TO_SEQNUM(ptr)     ((uint16_t)*(ptr        \
  52                                                + 2) * 256 \
  53                                    + (uint16_t)*(ptr + 3))
  54 #define HEADER_TO_PACKETS(ptr)    ((uint16_t)*(ptr        \
  55                                                + 4) * 256 \
  56                                    + (uint16_t)*(ptr + 5))
  57
  58 /* states of connection */
  59 enum conn_states
  60 {
  61   conn_read,         /* reading in a command line */
  62   conn_write,        /* writing out a simple response */
  63   conn_closing      /* closing this connection */
  64 };
  65
  66 /* returned states of memcached command */
  67 enum mcd_ret
  68 {
  69   MCD_SUCCESS,                      /* command success */
  70   MCD_FAILURE,                      /* command failure */
  71   MCD_UNKNOWN_READ_FAILURE,         /* unknown read failure */
  72   MCD_PROTOCOL_ERROR,               /* protocol error */
  73   MCD_CLIENT_ERROR,                 /* client error, wrong command */
  74   MCD_SERVER_ERROR,                 /* server error, server run command failed */
  75   MCD_DATA_EXISTS,                  /* object is existent in server */
  76   MCD_NOTSTORED,                    /* server doesn't set the object successfully */
  77   MCD_STORED,                       /* server set the object successfully */
  78   MCD_NOTFOUND,                     /* server not find the object */
  79   MCD_END,                          /* end of the response of get command */
  80   MCD_DELETED,                      /* server delete the object successfully */
  81   MCD_STAT                         /* response of stats command */
  82 };
  83
  84 /* used to store the current or previous running command state */
  85 typedef struct cmdstat
  86 {
  87   int cmd;                  /* command name */
  88   int retstat;              /* return state of this command */
  89   bool isfinish;            /* if it read all the response data */
  90   uint64_t key_prefix;      /* key prefix */
  91 } ms_cmdstat_t;
  92
  93 /* udp packet structure */
  94 typedef struct udppkt
  95 {
  96   uint8_t *header;          /* udp header of the packet */
  97   char *data;               /* udp data of the packet */
  98   int rbytes;               /* number of data in the packet */
  99   int copybytes;            /* number of copied data in the packet */
 100 } ms_udppkt_t;
 101
 102 /* three protocols supported */
 103 enum protocol
 104 {
 105   ascii_prot = 3,           /* ASCII protocol */
 106   binary_prot              /* binary protocol */
 107 };
 108
 109 /**
 110  *  concurrency structure
 111  *
 112  *  Each thread has a libevent to manage the events of network.
 113  *  Each thread has one or more self-governed concurrencies;
 114  *  each concurrency has one or more socket connections. This
 115  *  concurrency structure includes all the private variables of
 116  *  the concurrency.
 117  */
 118 typedef struct conn
 119 {
 120   uint32_t conn_idx;             /* connection index in the thread */
 121   int sfd;                  /* current tcp sock handler of the connection structure */
 122   int udpsfd;               /* current udp sock handler of the connection structure*/
 123   int state;                /* state of the connection */
 124   struct event event;       /* event for libevent */
 125   short ev_flags;           /* event flag for libevent */
 126   short which;              /* which events were just triggered */
 127   bool change_sfd;          /* whether change sfd */
 128
 129   int *tcpsfd;              /* TCP sock array */
 130   uint32_t total_sfds;           /* how many socks in the tcpsfd array */
 131   uint32_t alive_sfds;           /* alive socks */
 132   uint32_t cur_idx;              /* current sock index in tcpsfd array */
 133
 134   ms_cmdstat_t precmd;      /* previous command state */
 135   ms_cmdstat_t currcmd;     /* current command state */
 136
 137   char *rbuf;               /* buffer to read commands into */
 138   char *rcurr;              /* but if we parsed some already, this is where we stopped */
 139   int rsize;                /* total allocated size of rbuf */
 140   int rbytes;               /* how much data, starting from rcur, do we have unparsed */
 141
 142   bool readval;             /* read value state, read known data size */
 143   int rvbytes;              /* total value size need to read */
 144
 145   char *wbuf;               /* buffer to write commands out */
 146   char *wcurr;              /* for multi-get, where we stopped */
 147   int wsize;                /* total allocated size of wbuf */
 148   bool ctnwrite;            /* continue to write */
 149
 150   /* data for the mwrite state */
 151   struct iovec *iov;
 152   int iovsize;              /* number of elements allocated in iov[] */
 153   int iovused;              /* number of elements used in iov[] */
 154
 155   struct msghdr *msglist;
 156   int msgsize;              /* number of elements allocated in msglist[] */
 157   int msgused;              /* number of elements used in msglist[] */
 158   int msgcurr;              /* element in msglist[] being transmitted now */
 159   int msgbytes;             /* number of bytes in current msg */
 160
 161   /* data for UDP clients */
 162   bool udp;                          /* is this is a UDP "connection" */
 163   uint32_t request_id;                   /* UDP request ID of current operation, if this is a UDP "connection" */
 164   uint8_t *hdrbuf;                  /* udp packet headers */
 165   int hdrsize;                      /* number of headers' worth of space is allocated */
 166   struct  sockaddr srv_recv_addr;   /* Sent the most recent request to which server */
 167   socklen_t srv_recv_addr_size;
 168
 169   /* udp read buffer */
 170   char *rudpbuf;                    /* buffer to read commands into for udp */
 171   int rudpsize;                     /* total allocated size of rudpbuf */
 172   int rudpbytes;                    /* how much data, starting from rudpbuf */
 173
 174   /* order udp packet */
 175   ms_udppkt_t *udppkt;              /* the offset of udp packet in rudpbuf */
 176   int packets;                      /* number of total packets need to read */
 177   int recvpkt;                      /* number of received packets */
 178   int pktcurr;                      /* current packet in rudpbuf being ordered */
 179   int ordcurr;                      /* current ordered packet */
 180
 181   ms_task_item_t *item_win;         /* task sequence */
 182   int win_size;                     /* current task window size */
 183   uint64_t set_cursor;              /* current set item index in the item window */
 184   ms_task_t curr_task;              /* current running task */
 185   ms_mlget_task_t mlget_task;       /* multi-get task */
 186
 187   int warmup_num;                   /* to run how many warm up operations*/
 188   int remain_warmup_num;            /* left how many warm up operations to run */
 189   int64_t exec_num;                 /* to run how many task operations */
 190   int64_t remain_exec_num;          /* how many remained task operations to run */
 191
 192   /* response time statistic and time out control */
 193   struct timeval start_time;        /* start time of current operation(s) */
 194   struct timeval end_time;          /* end time of current operation(s) */
 195
 196   /* Binary protocol stuff */
 197   protocol_binary_response_header binary_header;    /* local temporary binary header */
 198   enum protocol protocol;                           /* which protocol this connection speaks */
 199 } ms_conn_t;
 200
 201 /* used to generate the key prefix */
 202 uint64_t ms_get_key_prefix(void);
 203
 204
 205 /**
 206  * setup a connection, each connection structure of each
 207  * thread must call this function to initialize.
 208  */
 209 int ms_setup_conn(ms_conn_t *c);
 210
 211
 212 /* after one operation completes, reset the connection */
 213 void ms_reset_conn(ms_conn_t *c, bool timeout);
 214
 215
 216 /**
 217  *  reconnect several disconnected socks in the connection
 218  *  structure, the ever-1-second timer of the thread will check
 219  *  whether some socks in the connections disconnect. if
 220  *  disconnect, reconnect the sock.
 221  */
 222 int ms_reconn_socks(ms_conn_t *c);
 223
 224
 225 /* used to send set command to server */
 226 int ms_mcd_set(ms_conn_t *c, ms_task_item_t *item);
 227
 228
 229 /* used to send the get command to server */
 230 int ms_mcd_get(ms_conn_t *c, ms_task_item_t *item);
 231
 232
 233 /* used to send the multi-get command to server */
 234 int ms_mcd_mlget(ms_conn_t *c);
 235
 236
 237 #ifdef __cplusplus
 238 }
 239 #endif
 240
 241 #endif /* end of MS_CONN_H */