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