src/helper.h

   1 /*
   2  * DEBUG: section 84    Helper process maintenance
   3  * AUTHOR: Harvest Derived?
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  */
  32
  33 #ifndef SQUID_HELPER_H
  34 #define SQUID_HELPER_H
  35
  36 #include "squid.h"
  37 #include "cbdata.h"
  38 #include "comm/forward.h"
  39 #include "ip/Address.h"
  40 #include "HelperChildConfig.h"
  41
  42 class helper_request;
  43
  44 typedef void HLPSCB(void *, void *lastserver, char *buf);
  45
  46 class helper
  47 {
  48 public:
  49     inline helper(const char *name) : cmdline(NULL), id_name(name), eom('\n') {}
  50     ~helper();
  51
  52 public:
  53     wordlist *cmdline;
  54     dlink_list servers;
  55     dlink_list queue;
  56     const char *id_name;
  57     HelperChildConfig childs;    ///< Configuration settings for number running.
  58     int ipc_type;
  59     Ip::Address addr;
  60     time_t last_queue_warn;
  61     time_t last_restart;
  62     char eom;   ///< The char which marks the end of (response) message, normally '\n'
  63
  64     struct _stats {
  65         int requests;
  66         int replies;
  67         int queue_size;
  68         int avg_svc_time;
  69     } stats;
  70
  71 private:
  72     CBDATA_CLASS2(helper);
  73 };
  74
  75 class statefulhelper : public helper
  76 {
  77 public:
  78     inline statefulhelper(const char *name) : helper(name) {};
  79     inline ~statefulhelper() {};
  80
  81 public:
  82     MemAllocator *datapool;
  83     HLPSAVAIL *IsAvailable;
  84     HLPSONEQ *OnEmptyQueue;
  85
  86 private:
  87     CBDATA_CLASS2(statefulhelper);
  88 };
  89
  90 /*
  91  * Fields shared between stateless and stateful helper servers.
  92  */
  93 class HelperServerBase
  94 {
  95 public:
  96     /** Closes pipes to the helper safely.
  97      * Handles the case where the read and write pipes are the same FD.
  98      */
  99     void closePipesSafely();
 100
 101     /** Closes the reading pipe.
 102      * If the read and write sockets are the same the write pipe will
 103      * also be closed. Otherwise its left open for later handling.
 104      */
 105     void closeWritePipeSafely();
 106
 107 public:
 108     int index;
 109     int pid;
 110     Ip::Address addr;
 111     Comm::ConnectionPointer readPipe;
 112     Comm::ConnectionPointer writePipe;
 113     void *hIpc;
 114
 115     char *rbuf;
 116     size_t rbuf_sz;
 117     size_t roffset;
 118
 119     struct timeval dispatch_time;
 120     struct timeval answer_time;
 121
 122     dlink_node link;
 123
 124     struct _helper_flags {
 125         unsigned int busy:1;
 126         unsigned int writing:1;
 127         unsigned int closing:1;
 128         unsigned int shutdown:1;
 129         unsigned int reserved:1;
 130     } flags;
 131
 132 };
 133
 134 class helper_server : public HelperServerBase
 135 {
 136 public:
 137     MemBuf *wqueue;
 138     MemBuf *writebuf;
 139
 140     helper *parent;
 141     helper_request **requests;
 142
 143     struct {
 144         int uses;
 145         unsigned int pending;
 146     } stats;
 147 };
 148
 149 class helper_stateful_request;
 150
 151 class helper_stateful_server : public HelperServerBase
 152 {
 153 public:
 154     /* MemBuf wqueue; */
 155     /* MemBuf writebuf; */
 156
 157     statefulhelper *parent;
 158     helper_stateful_request *request;
 159
 160     struct {
 161         int uses;
 162         int submits;
 163         int releases;
 164     } stats;
 165     void *data;                 /* State data used by the calling routines */
 166 };
 167
 168 class helper_request
 169 {
 170
 171 public:
 172     MEMPROXY_CLASS(helper_request);
 173     char *buf;
 174     HLPCB *callback;
 175     void *data;
 176
 177     struct timeval dispatch_time;
 178 };
 179
 180 MEMPROXY_CLASS_INLINE(helper_request);
 181
 182 class helper_stateful_request
 183 {
 184
 185 public:
 186     MEMPROXY_CLASS(helper_stateful_request);
 187     char *buf;
 188     HLPSCB *callback;
 189     int placeholder;            /* if 1, this is a dummy request waiting for a stateful helper to become available */
 190     void *data;
 191 };
 192
 193 MEMPROXY_CLASS_INLINE(helper_stateful_request);
 194
 195 /* helper.c */
 196 SQUIDCEXTERN void helperOpenServers(helper * hlp);
 197 SQUIDCEXTERN void helperStatefulOpenServers(statefulhelper * hlp);
 198 SQUIDCEXTERN void helperSubmit(helper * hlp, const char *buf, HLPCB * callback, void *data);
 199 SQUIDCEXTERN void helperStatefulSubmit(statefulhelper * hlp, const char *buf, HLPSCB * callback, void *data, helper_stateful_server * lastserver);
 200 SQUIDCEXTERN void helperStats(StoreEntry * sentry, helper * hlp, const char *label = NULL);
 201 SQUIDCEXTERN void helperStatefulStats(StoreEntry * sentry, statefulhelper * hlp, const char *label = NULL);
 202 SQUIDCEXTERN void helperShutdown(helper * hlp);
 203 SQUIDCEXTERN void helperStatefulShutdown(statefulhelper * hlp);
 204 SQUIDCEXTERN void helperStatefulReleaseServer(helper_stateful_server * srv);
 205 SQUIDCEXTERN void *helperStatefulServerGetData(helper_stateful_server * srv);
 206
 207
 208 #endif /* SQUID_HELPER_H */