src/MemObject.h

   1 /*
   2  * $Id$
   3  *
   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_MEMOBJECT_H
  34 #define SQUID_MEMOBJECT_H
  35
  36 #include "StoreIOBuffer.h"
  37 #include "StoreIOState.h"
  38 #include "stmem.h"
  39 #include "CommRead.h"
  40 #include "RemovalPolicy.h"
  41 #include "HttpRequestMethod.h"
  42
  43 typedef void STMCB (void *data, StoreIOBuffer wroteBuffer);
  44
  45 class store_client;
  46 #if USE_DELAY_POOLS
  47 #include "DelayId.h"
  48 #endif
  49
  50 class MemObject
  51 {
  52
  53 public:
  54     static size_t inUseCount();
  55     MEMPROXY_CLASS(MemObject);
  56
  57     void dump() const;
  58     MemObject(char const *, char const *);
  59     ~MemObject();
  60
  61     void write(StoreIOBuffer, STMCB *, void *);
  62     void unlinkRequest();
  63     HttpReply const *getReply() const;
  64     void replaceHttpReply(HttpReply *newrep);
  65     void stat (MemBuf * mb) const;
  66     int64_t endOffset () const;
  67     int64_t size() const;
  68     void reset();
  69     int64_t lowestMemReaderOffset() const;
  70     bool readAheadPolicyCanRead() const;
  71     void addClient(store_client *);
  72     /* XXX belongs in MemObject::swapout, once swaphdrsz is managed
  73      * better
  74      */
  75     int64_t objectBytesOnDisk() const;
  76     int64_t policyLowestOffsetToKeep(bool swap) const;
  77     void trimSwappable();
  78     void trimUnSwappable();
  79     bool isContiguous() const;
  80     int mostBytesWanted(int max) const;
  81     void setNoDelay(bool const newValue);
  82 #if USE_DELAY_POOLS
  83     DelayId mostBytesAllowed() const;
  84 #endif
  85
  86
  87 #if URL_CHECKSUM_DEBUG
  88
  89     void checkUrlChecksum() const;
  90 #endif
  91
  92     HttpRequestMethod method;
  93     char *url;
  94     mem_hdr data_hdr;
  95     int64_t inmem_lo;
  96     dlink_list clients;
  97
  98     /** \todo move into .cc or .cci */
  99     size_t clientCount() const {return nclients;}
 100
 101     bool clientIsFirst(void *sc) const {return (clients.head && sc == clients.head->data);}
 102
 103     int nclients;
 104
 105     class SwapOut
 106     {
 107
 108     public:
 109         int64_t queue_offset;     /* relative to in-mem data */
 110         mem_node *memnode;      /* which node we're currently paging out */
 111         StoreIOState::Pointer sio;
 112     };
 113
 114     SwapOut swapout;
 115
 116     /* Read only - this reply must be preserved by store clients */
 117     /* The original reply. possibly with updated metadata. */
 118     HttpRequest *request;
 119
 120     struct timeval start_ping;
 121     IRCB *ping_reply_callback;
 122     void *ircb_data;
 123
 124     struct {
 125         STABH *callback;
 126         void *data;
 127     } abort;
 128     char *log_url;
 129     RemovalPolicyNode repl;
 130     int id;
 131     int64_t object_sz;
 132     size_t swap_hdr_sz;
 133 #if URL_CHECKSUM_DEBUG
 134
 135     unsigned int chksum;
 136 #endif
 137
 138     const char *vary_headers;
 139
 140     void delayRead(DeferredRead const &);
 141     void kickReads();
 142
 143 private:
 144     HttpReply *_reply;
 145
 146     DeferredReadManager deferredReads;
 147 };
 148
 149 MEMPROXY_CLASS_INLINE(MemObject);
 150
 151 /** global current memory removal policy */
 152 extern RemovalPolicy *mem_policy;
 153
 154 #endif /* SQUID_MEMOBJECT_H */