src/HttpHdrSc.cc

   1
   2 /*
   3  * $Id$
   4  *
   5  * DEBUG: section 90    HTTP Cache Control Header
   6  * AUTHOR: Alex Rousskov
   7  *         Robert Collins (Surrogate-Control is derived from
   8  *                         Cache-Control).
   9  *         Francesco Chemolli (c++ refactoring)
  10  *
  11  * SQUID Web Proxy Cache          http://www.squid-cache.org/
  12  * ----------------------------------------------------------
  13  *
  14  *  Squid is the result of efforts by numerous individuals from
  15  *  the Internet community; see the CONTRIBUTORS file for full
  16  *  details.   Many organizations have provided support for Squid's
  17  *  development; see the SPONSORS file for full details.  Squid is
  18  *  Copyrighted (C) 2001 by the Regents of the University of
  19  *  California; see the COPYRIGHT file for full details.  Squid
  20  *  incorporates software developed and/or copyrighted by other
  21  *  sources; see the CREDITS file for full details.
  22  *
  23  *  This program is free software; you can redistribute it and/or modify
  24  *  it under the terms of the GNU General Public License as published by
  25  *  the Free Software Foundation; either version 2 of the License, or
  26  *  (at your option) any later version.
  27  *
  28  *  This program is distributed in the hope that it will be useful,
  29  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  30  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  31  *  GNU General Public License for more details.
  32  *
  33  *  You should have received a copy of the GNU General Public License
  34  *  along with this program; if not, write to the Free Software
  35  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  36  *
  37  */
  38
  39 #include "squid.h"
  40 #include "HttpHdrSc.h"
  41 #include "HttpHeader.h"
  42 #include "HttpHeaderStat.h"
  43 #include "HttpHeaderTools.h"
  44 #include "Store.h"
  45 #include "protos.h"
  46
  47 #if HAVE_MAP
  48 #include <map>
  49 #endif
  50
  51 /* a row in the table used for parsing surrogate-control header and statistics */
  52 typedef struct {
  53     const char *name;
  54     http_hdr_sc_type id;
  55     HttpHeaderFieldStat stat;
  56 } HttpHeaderScFields;
  57
  58 /* this table is used for parsing surrogate control header */
  59 /* order must match that of enum http_hdr_sc_type. The constraint is verified at initialization time */
  60 //todo: implement constraint
  61 static const HttpHeaderFieldAttrs ScAttrs[SC_ENUM_END] = {
  62     {"no-store", (http_hdr_type)SC_NO_STORE},
  63     {"no-store-remote", (http_hdr_type)SC_NO_STORE_REMOTE},
  64     {"max-age", (http_hdr_type)SC_MAX_AGE},
  65     {"content", (http_hdr_type)SC_CONTENT},
  66     {"Other,", (http_hdr_type)SC_OTHER} /* ',' will protect from matches */
  67 };
  68
  69 HttpHeaderFieldInfo *ScFieldsInfo = NULL;
  70
  71 http_hdr_sc_type &operator++ (http_hdr_sc_type &aHeader)
  72 {
  73     int tmp = (int)aHeader;
  74     aHeader = (http_hdr_sc_type)(++tmp);
  75     return aHeader;
  76 }
  77
  78 int operator - (http_hdr_sc_type const &anSc, http_hdr_sc_type const &anSc2)
  79 {
  80     return (int)anSc - (int)anSc2;
  81 }
  82
  83 /* module initialization */
  84
  85 void
  86 httpHdrScInitModule(void)
  87 {
  88     ScFieldsInfo = httpHeaderBuildFieldsInfo(ScAttrs, SC_ENUM_END);
  89 }
  90
  91 void
  92 httpHdrScCleanModule(void)
  93 {
  94     httpHeaderDestroyFieldsInfo(ScFieldsInfo, SC_ENUM_END);
  95     ScFieldsInfo = NULL;
  96 }
  97
  98 /* implementation */
  99
 100 /* creates an sc object from a 0-terminating string */
 101 HttpHdrSc *
 102 httpHdrScParseCreate(const String & str)
 103 {
 104     HttpHdrSc *sc = new HttpHdrSc();
 105
 106     if (!sc->parse(&str)) {
 107         delete sc;
 108         sc = NULL;
 109     }
 110
 111     return sc;
 112 }
 113
 114 /* parses a 0-terminating string and inits sc */
 115 bool
 116 HttpHdrSc::parse(const String * str)
 117 {
 118     HttpHdrSc * sc=this;
 119     const char *item;
 120     const char *p;              /* '=' parameter */
 121     const char *pos = NULL;
 122     const char *target = NULL; /* ;foo */
 123     const char *temp = NULL; /* temp buffer */
 124     int type;
 125     int ilen, vlen;
 126     int initiallen;
 127     HttpHdrScTarget *sct;
 128     assert(str);
 129
 130     /* iterate through comma separated list */
 131
 132     while (strListGetItem(str, ',', &item, &ilen, &pos)) {
 133         initiallen = ilen;
 134         vlen = 0;
 135         /* decrease ilen to still match the token for  '=' statements */
 136
 137         if ((p = strchr(item, '=')) && (p - item < ilen)) {
 138             vlen = ilen - (p + 1 - item);
 139             ilen = p - item;
 140             ++p;
 141         }
 142
 143         /* decrease ilen to still match the token for ';' qualified non '=' statments */
 144         else if ((p = strchr(item, ';')) && (p - item < ilen)) {
 145             ilen = p - item;
 146             ++p;
 147         }
 148
 149         /* find type */
 150         /* TODO: use a type-safe map-based lookup */
 151         type = httpHeaderIdByName(item, ilen,
 152                                   ScFieldsInfo, SC_ENUM_END);
 153
 154         if (type < 0) {
 155             debugs(90, 2, "hdr sc: unknown control-directive: near '" << item << "' in '" << str << "'");
 156             type = SC_OTHER;
 157         }
 158
 159         /* Is this a targeted directive? */
 160         /* TODO: remove the temporary useage and use memrchr and the information we have instead */
 161         temp = xstrndup (item, initiallen + 1);
 162
 163         if (!((target = strrchr (temp, ';')) && !strchr (target, '"') && *(target + 1) != '\0'))
 164             target = NULL;
 165         else
 166             ++target;
 167
 168         sct = sc->findTarget(target);
 169
 170         if (!sct) {
 171             sct = new HttpHdrScTarget(target);
 172             addTarget(sct);
 173         }
 174
 175         safe_free (temp);
 176
 177         if (sct->isSet(static_cast<http_hdr_sc_type>(type))) {
 178             if (type != SC_OTHER)
 179                 debugs(90, 2, "hdr sc: ignoring duplicate control-directive: near '" << item << "' in '" << str << "'");
 180
 181             ++ ScFieldsInfo[type].stat.repCount;
 182
 183             continue;
 184         }
 185
 186         /* process directives */
 187         switch (type) {
 188         case SC_NO_STORE:
 189             sct->noStore(true);
 190             break;
 191
 192         case SC_NO_STORE_REMOTE:
 193             sct->noStoreRemote(true);
 194             break;
 195
 196         case SC_MAX_AGE: {
 197             int ma;
 198             if (p && httpHeaderParseInt(p, &ma)) {
 199                 sct->maxAge(ma);
 200             } else {
 201                 debugs(90, 2, "sc: invalid max-age specs near '" << item << "'");
 202                 sct->clearMaxAge();
 203             }
 204
 205             if ((p = strchr (p, '+'))) {
 206                 int ms;
 207                 ++p; //skip the + char
 208                 if (httpHeaderParseInt(p, &ms)) {
 209                     sct->maxStale(ms);
 210                 } else {
 211                     debugs(90, 2, "sc: invalid max-stale specs near '" << item << "'");
 212                     sct->clearMaxStale();
 213                     /* leave the max-age alone */
 214                 }
 215             }
 216             break;
 217         }
 218
 219         case SC_CONTENT:
 220
 221             if ( p && httpHeaderParseQuotedString(p, vlen, &sct->content_)) {
 222                 sct->setMask(SC_CONTENT,true); // ugly but saves a copy
 223             } else {
 224                 debugs(90, 2, "sc: invalid content= quoted string near '" << item << "'");
 225                 sct->clearContent();
 226             }
 227             break;
 228
 229         case SC_OTHER:
 230         default:
 231             break;
 232         }
 233     }
 234
 235     return sc->targets.head != NULL;
 236 }
 237
 238 HttpHdrSc::~HttpHdrSc()
 239 {
 240     if (targets.head) {
 241         dlink_node *sct = targets.head;
 242
 243         while (sct) {
 244             HttpHdrScTarget *t = static_cast<HttpHdrScTarget *>(sct->data);
 245             sct = sct->next;
 246             dlinkDelete (&t->node, &targets);
 247             delete t;
 248         }
 249     }
 250 }
 251
 252 HttpHdrSc::HttpHdrSc(const HttpHdrSc &sc)
 253 {
 254     dlink_node *node = sc.targets.head;
 255
 256     while (node) {
 257         HttpHdrScTarget *dupsct = new HttpHdrScTarget(*static_cast<HttpHdrScTarget *>(node->data));
 258         addTargetAtTail(dupsct);
 259         node = node->next;
 260     }
 261 }
 262
 263 void
 264 HttpHdrScTarget::packInto(Packer * p) const
 265 {
 266     http_hdr_sc_type flag;
 267     int pcount = 0;
 268     assert (p);
 269
 270     for (flag = SC_NO_STORE; flag < SC_ENUM_END; ++flag) {
 271         if (isSet(flag) && flag != SC_OTHER) {
 272
 273             /* print option name */
 274             packerPrintf(p, (pcount ? ", " SQUIDSTRINGPH : SQUIDSTRINGPH),
 275                          SQUIDSTRINGPRINT(ScFieldsInfo[flag].name));
 276
 277             /* handle options with values */
 278
 279             if (flag == SC_MAX_AGE)
 280                 packerPrintf(p, "=%d", (int) max_age);
 281
 282             if (flag == SC_CONTENT)
 283                 packerPrintf(p, "=\"" SQUIDSTRINGPH "\"", SQUIDSTRINGPRINT(content_));
 284
 285             ++pcount;
 286         }
 287     }
 288
 289     if (hasTarget())
 290         packerPrintf (p, ";" SQUIDSTRINGPH, SQUIDSTRINGPRINT(target));
 291 }
 292
 293 void
 294 HttpHdrSc::packInto(Packer * p) const
 295 {
 296     dlink_node *node;
 297     assert(p);
 298     node = targets.head;
 299
 300     while (node) {
 301         static_cast<HttpHdrScTarget *>(node->data)->packInto(p);
 302         node = node->next;
 303     }
 304 }
 305
 306 /* negative max_age will clean old max_Age setting */
 307 void
 308 HttpHdrSc::setMaxAge(char const *target, int max_age)
 309 {
 310     HttpHdrScTarget *sct = findTarget(target);
 311
 312     if (!sct) {
 313         sct = new HttpHdrScTarget(target);
 314         dlinkAddTail (sct, &sct->node, &targets);
 315     }
 316
 317     sct->maxAge(max_age);
 318 }
 319
 320 void
 321 HttpHdrSc::updateStats(StatHist * hist) const
 322 {
 323     dlink_node *sct = targets.head;
 324
 325     while (sct) {
 326         static_cast<HttpHdrScTarget *>(sct->data)->updateStats(hist);
 327         sct = sct->next;
 328     }
 329 }
 330
 331 void
 332 httpHdrScTargetStatDumper(StoreEntry * sentry, int idx, double val, double size, int count)
 333 {
 334     extern const HttpHeaderStat *dump_stat;     /* argh! */
 335     const int id = (int) val;
 336     const int valid_id = id >= 0 && id < SC_ENUM_END;
 337     const char *name = valid_id ? ScFieldsInfo[id].name.termedBuf() : "INVALID";
 338
 339     if (count || valid_id)
 340         storeAppendPrintf(sentry, "%2d\t %-20s\t %5d\t %6.2f\n",
 341                           id, name, count, xdiv(count, dump_stat->scParsedCount));
 342 }
 343
 344 void
 345 httpHdrScStatDumper(StoreEntry * sentry, int idx, double val, double size, int count)
 346 {
 347     extern const HttpHeaderStat *dump_stat;     /* argh! */
 348     const int id = (int) val;
 349     const int valid_id = id >= 0 && id < SC_ENUM_END;
 350     const char *name = valid_id ? ScFieldsInfo[id].name.termedBuf() : "INVALID";
 351
 352     if (count || valid_id)
 353         storeAppendPrintf(sentry, "%2d\t %-20s\t %5d\t %6.2f\n",
 354                           id, name, count, xdiv(count, dump_stat->scParsedCount));
 355 }
 356
 357 HttpHdrScTarget *
 358 HttpHdrSc::findTarget(const char *target)
 359 {
 360     dlink_node *node;
 361     node = targets.head;
 362
 363     while (node) {
 364         HttpHdrScTarget *sct = (HttpHdrScTarget *)node->data;
 365
 366         if (target && sct->target.defined() && !strcmp (target, sct->target.termedBuf()))
 367             return sct;
 368         else if (!target && sct->target.undefined())
 369             return sct;
 370
 371         node = node->next;
 372     }
 373
 374     return NULL;
 375 }
 376
 377 HttpHdrScTarget *
 378 HttpHdrSc::getMergedTarget(const char *ourtarget)
 379 {
 380     HttpHdrScTarget *sctus = findTarget(ourtarget);
 381     HttpHdrScTarget *sctgeneric = findTarget(NULL);
 382
 383     if (sctgeneric || sctus) {
 384         HttpHdrScTarget *sctusable = new HttpHdrScTarget(NULL);
 385
 386         if (sctgeneric)
 387             sctusable->mergeWith(sctgeneric);
 388
 389         if (sctus)
 390             sctusable->mergeWith(sctus);
 391
 392         return sctusable;
 393     }
 394
 395     return NULL;
 396 }