src/PeerSelectState.h

   1 /*
   2  * AUTHOR: Robert Collins
   3  *
   4  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   5  * ----------------------------------------------------------
   6  *
   7  *  Squid is the result of efforts by numerous individuals from
   8  *  the Internet community; see the CONTRIBUTORS file for full
   9  *  details.   Many organizations have provided support for Squid's
  10  *  development; see the SPONSORS file for full details.  Squid is
  11  *  Copyrighted (C) 2001 by the Regents of the University of
  12  *  California; see the COPYRIGHT file for full details.  Squid
  13  *  incorporates software developed and/or copyrighted by other
  14  *  sources; see the CREDITS file for full details.
  15  *
  16  *  This program is free software; you can redistribute it and/or modify
  17  *  it under the terms of the GNU General Public License as published by
  18  *  the Free Software Foundation; either version 2 of the License, or
  19  *  (at your option) any later version.
  20  *
  21  *  This program is distributed in the hope that it will be useful,
  22  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  *  GNU General Public License for more details.
  25  *
  26  *  You should have received a copy of the GNU General Public License
  27  *  along with this program; if not, write to the Free Software
  28  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  29  *
  30  * Copyright (c) 2003, Robert Collins <robertc@squid-cache.org>
  31  */
  32
  33 #ifndef   SQUID_PEERSELECTSTATE_H
  34 #define   SQUID_PEERSELECTSTATE_H
  35
  36 #include "acl/Checklist.h"
  37 #include "Array.h"
  38 #include "cbdata.h"
  39 #include "comm/forward.h"
  40 #include "hier_code.h"
  41 #include "PingData.h"
  42 #include "ip/Address.h"
  43
  44 class HttpRequest;
  45 class StoreEntry;
  46 class ErrorState;
  47
  48 typedef void PSC(Comm::ConnectionList *, ErrorState *, void *);
  49
  50 SQUIDCEXTERN void peerSelect(Comm::ConnectionList *, HttpRequest *, StoreEntry *, PSC *, void *data);
  51 SQUIDCEXTERN void peerSelectInit(void);
  52
  53 /**
  54  * A CachePeer which has been selected as a possible destination.
  55  * Listed as pointers here so as to prevent duplicates being added but will
  56  * be converted to a set of IP address path options before handing back out
  57  * to the caller.
  58  *
  59  * Certain connection flags and outgoing settings will also be looked up and
  60  * set based on the received request and CachePeer settings before handing back.
  61  */
  62 class FwdServer
  63 {
  64 public:
  65     CachePeer *_peer;                /* NULL --> origin server */
  66     hier_code code;
  67     FwdServer *next;
  68 };
  69
  70 class ps_state
  71 {
  72
  73 public:
  74     void *operator new(size_t);
  75     ps_state();
  76     HttpRequest *request;
  77     StoreEntry *entry;
  78     allow_t always_direct;
  79     allow_t never_direct;
  80     int direct;   // TODO: fold always_direct/never_direct/prefer_direct into this now that ACL can do a multi-state result.
  81     PSC *callback;
  82     void *callback_data;
  83     ErrorState *lastError;
  84
  85     Comm::ConnectionList *paths;    ///< the callers paths array. to be filled with our final results.
  86     FwdServer *servers;    ///< temporary linked list of peers we will pass back.
  87
  88     /*
  89      * Why are these Ip::Address instead of CachePeer *?  Because a
  90      * CachePeer structure can become invalid during the CachePeer selection
  91      * phase, specifically after a reconfigure.  Thus we need to lookup
  92      * the CachePeer * based on the address when we are finally ready to
  93      * reference the CachePeer structure.
  94      */
  95
  96     Ip::Address first_parent_miss;
  97
  98     Ip::Address closest_parent_miss;
  99     /*
 100      * ->hit can be CachePeer* because it should only be
 101      * accessed during the thread when it is set
 102      */
 103     CachePeer *hit;
 104     peer_t hit_type;
 105     ping_data ping;
 106     ACLChecklist *acl_checklist;
 107 private:
 108     CBDATA_CLASS(ps_state);
 109 };
 110
 111 #endif /* SQUID_PEERSELECTSTATE_H */