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     /// negative if unknown; otherwise, expected object_sz, expected endOffset
  68     /// maximum, and stored reply headers+body size (all three are the same)
  69     int64_t expectedReplySize() const;
  70     int64_t size() const;
  71     void reset();
  72     int64_t lowestMemReaderOffset() const;
  73     bool readAheadPolicyCanRead() const;
  74     void addClient(store_client *);
  75     /* XXX belongs in MemObject::swapout, once swaphdrsz is managed
  76      * better
  77      */
  78     int64_t objectBytesOnDisk() const;
  79     int64_t policyLowestOffsetToKeep(bool swap) const;
  80     void trimSwappable();
  81     void trimUnSwappable();
  82     bool isContiguous() const;
  83     int mostBytesWanted(int max) const;
  84     void setNoDelay(bool const newValue);
  85 #if USE_DELAY_POOLS
  86     DelayId mostBytesAllowed() const;
  87 #endif
  88
  89
  90 #if URL_CHECKSUM_DEBUG
  91
  92     void checkUrlChecksum() const;
  93 #endif
  94
  95     HttpRequestMethod method;
  96     char *url;
  97     mem_hdr data_hdr;
  98     int64_t inmem_lo;
  99     dlink_list clients;
 100
 101     /** \todo move into .cc or .cci */
 102     size_t clientCount() const {return nclients;}
 103
 104     bool clientIsFirst(void *sc) const {return (clients.head && sc == clients.head->data);}
 105
 106     int nclients;
 107
 108     class SwapOut
 109     {
 110
 111     public:
 112         int64_t queue_offset; ///< number of bytes sent to SwapDir for writing
 113         StoreIOState::Pointer sio;
 114     };
 115
 116     SwapOut swapout;
 117
 118     /* Read only - this reply must be preserved by store clients */
 119     /* The original reply. possibly with updated metadata. */
 120     HttpRequest *request;
 121
 122     struct timeval start_ping;
 123     IRCB *ping_reply_callback;
 124     void *ircb_data;
 125
 126     struct {
 127         STABH *callback;
 128         void *data;
 129     } abort;
 130     char *log_url;
 131     RemovalPolicyNode repl;
 132     int id;
 133     int64_t object_sz;
 134     size_t swap_hdr_sz;
 135 #if URL_CHECKSUM_DEBUG
 136
 137     unsigned int chksum;
 138 #endif
 139
 140     const char *vary_headers;
 141
 142     void delayRead(DeferredRead const &);
 143     void kickReads();
 144
 145 private:
 146     HttpReply *_reply;
 147
 148     DeferredReadManager deferredReads;
 149 };
 150
 151 MEMPROXY_CLASS_INLINE(MemObject);
 152
 153 /** global current memory removal policy */
 154 extern RemovalPolicy *mem_policy;
 155
 156 #endif /* SQUID_MEMOBJECT_H */