src/StoreMeta.cc

   1
   2 /*
   3  * $Id: StoreMeta.cc,v 1.6 2007/09/19 08:54:51 hno Exp $
   4  *
   5  * DEBUG: section 20    Storage Manager Swapfile Metadata
   6  * AUTHOR: Kostas Anagnostakis
   7  *
   8  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   9  * ----------------------------------------------------------
  10  *
  11  *  Squid is the result of efforts by numerous individuals from
  12  *  the Internet community; see the CONTRIBUTORS file for full
  13  *  details.   Many organizations have provided support for Squid's
  14  *  development; see the SPONSORS file for full details.  Squid is
  15  *  Copyrighted (C) 2001 by the Regents of the University of
  16  *  California; see the COPYRIGHT file for full details.  Squid
  17  *  incorporates software developed and/or copyrighted by other
  18  *  sources; see the CREDITS file for full details.
  19  *
  20  *  This program is free software; you can redistribute it and/or modify
  21  *  it under the terms of the GNU General Public License as published by
  22  *  the Free Software Foundation; either version 2 of the License, or
  23  *  (at your option) any later version.
  24  *
  25  *  This program is distributed in the hope that it will be useful,
  26  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28  *  GNU General Public License for more details.
  29  *
  30  *  You should have received a copy of the GNU General Public License
  31  *  along with this program; if not, write to the Free Software
  32  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  33  *
  34  */
  35
  36 #include "squid.h"
  37 #include "StoreMeta.h"
  38 #include "Store.h"
  39 #include "MemObject.h"
  40 #include "StoreMetaMD5.h"
  41 #include "StoreMetaURL.h"
  42 #include "StoreMetaSTD.h"
  43 #include "StoreMetaSTDLFS.h"
  44 #include "StoreMetaVary.h"
  45 #include "StoreMetaObjSize.h"
  46
  47 bool
  48 StoreMeta::validType(char type)
  49 {
  50     /* VOID is reserved, and new types have to be added as classes */
  51
  52     if (type <= STORE_META_VOID || type >= STORE_META_END) {
  53         debugs(20, 0, "storeSwapMetaUnpack: bad type (" << type << ")!");
  54         return false;
  55     }
  56
  57     /* Unused in any current squid code */
  58     if (type == STORE_META_KEY_URL ||
  59             type == STORE_META_KEY_SHA ||
  60             type == STORE_META_HITMETERING ||
  61             type == STORE_META_VALID) {
  62         debugs(20, 0, "Obsolete and unused type (" << type << ") in disk metadata");
  63         return false;
  64     }
  65
  66     return true;
  67 }
  68
  69 class IntRange
  70 {
  71
  72 public:
  73     IntRange (int minimum, int maximum) : _min (minimum), _max (maximum)
  74     {
  75         if (_min > _max) {
  76             int temp = _min;
  77             _min = _max;
  78             _max = temp;
  79         }
  80     }
  81
  82     bool includes (int anInt) const
  83     {
  84         if (anInt < _min || anInt > _max)
  85             return false;
  86
  87         return true;
  88     }
  89
  90 private:
  91     int _min;
  92     int _max;
  93 };
  94
  95 const int StoreMeta::MinimumTLVLength = 0;
  96 const int StoreMeta::MaximumTLVLength = 1 << 16;
  97
  98 bool
  99 StoreMeta::validLength(int length) const
 100 {
 101     if (!IntRange (MinimumTLVLength, MaximumTLVLength).includes(length)) {
 102         debugs(20, 0, "storeSwapMetaUnpack: insane length (" << length << ")!");
 103         return false;
 104     }
 105
 106     return true;
 107 }
 108
 109
 110 StoreMeta *
 111 StoreMeta::Factory (char type, size_t len, void const *value)
 112 {
 113     if (!validType(type))
 114         return NULL;
 115
 116     StoreMeta *result;
 117
 118     switch (type) {
 119
 120     case STORE_META_KEY:
 121         result = new StoreMetaMD5;
 122         break;
 123
 124     case STORE_META_URL:
 125         result = new StoreMetaURL;
 126         break;
 127
 128     case STORE_META_STD:
 129         result = new StoreMetaSTD;
 130         break;
 131
 132     case STORE_META_STD_LFS:
 133         result = new StoreMetaSTDLFS;
 134         break;
 135
 136      case STORE_META_OBJSIZE:
 137         result = new StoreMetaObjSize;
 138         break;
 139
 140     case STORE_META_VARY_HEADERS:
 141         result = new StoreMetaVary;
 142         break;
 143
 144     default:
 145         debugs(20, 0, "Attempt to create unknown concrete StoreMeta");
 146         return NULL;
 147     }
 148
 149     if (!result->validLength(len)) {
 150         delete result;
 151         return NULL;
 152     }
 153
 154     result->length = len;
 155     result->value = xmalloc(len);
 156     xmemcpy(result->value, value, len);
 157     return result;
 158 }
 159
 160 void
 161 StoreMeta::FreeList(StoreMeta **head)
 162 {
 163     StoreMeta *node;
 164
 165     while ((node = *head) != NULL) {
 166         *head = node->next;
 167         xfree(node->value);
 168         delete node;
 169     }
 170 }
 171
 172 StoreMeta **
 173 StoreMeta::Add(StoreMeta **tail, StoreMeta *aNode)
 174 {
 175     assert (*tail == NULL);
 176     *tail = aNode;
 177     return &aNode->next;                /* return new tail pointer */
 178 }
 179
 180 bool
 181 StoreMeta::checkConsistency(StoreEntry *e) const
 182 {
 183     switch (getType()) {
 184
 185     case STORE_META_KEY:
 186
 187     case STORE_META_URL:
 188
 189     case STORE_META_VARY_HEADERS:
 190         assert(0);
 191         break;
 192
 193     case STORE_META_STD:
 194         break;
 195
 196     case STORE_META_STD_LFS:
 197         break;
 198
 199     case STORE_META_OBJSIZE:
 200         break;
 201
 202     default:
 203         debugs(20, 1, "WARNING: got unused STORE_META type " << getType());
 204         break;
 205     }
 206
 207     return true;
 208 }