src/HttpHdrSc.cc

   1
   2 /*
   3  * DEBUG: section 90    HTTP Cache Control Header
   4  * AUTHOR: Alex Rousskov
   5  *         Robert Collins (Surrogate-Control is derived from
   6  *                         Cache-Control).
   7  *         Francesco Chemolli (c++ refactoring)
   8  *
   9  * SQUID Web Proxy Cache          http://www.squid-cache.org/
  10  * ----------------------------------------------------------
  11  *
  12  *  Squid is the result of efforts by numerous individuals from
  13  *  the Internet community; see the CONTRIBUTORS file for full
  14  *  details.   Many organizations have provided support for Squid's
  15  *  development; see the SPONSORS file for full details.  Squid is
  16  *  Copyrighted (C) 2001 by the Regents of the University of
  17  *  California; see the COPYRIGHT file for full details.  Squid
  18  *  incorporates software developed and/or copyrighted by other
  19  *  sources; see the CREDITS file for full details.
  20  *
  21  *  This program is free software; you can redistribute it and/or modify
  22  *  it under the terms of the GNU General Public License as published by
  23  *  the Free Software Foundation; either version 2 of the License, or
  24  *  (at your option) any later version.
  25  *
  26  *  This program is distributed in the hope that it will be useful,
  27  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  29  *  GNU General Public License for more details.
  30  *
  31  *  You should have received a copy of the GNU General Public License
  32  *  along with this program; if not, write to the Free Software
  33  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  34  *
  35  */
  36
  37 #include "squid.h"
  38 #include "HttpHdrSc.h"
  39 #include "HttpHeader.h"
  40 #include "HttpHeaderFieldInfo.h"
  41 #include "HttpHeaderFieldStat.h"
  42 #include "HttpHeaderStat.h"
  43 #include "HttpHeaderTools.h"
  44 #include "Store.h"
  45 #include "StrList.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
 201                 if ((p = strchr (p, '+'))) {
 202                     int ms;
 203                     ++p; //skip the + char
 204                     if (httpHeaderParseInt(p, &ms)) {
 205                         sct->maxStale(ms);
 206                     } else {
 207                         debugs(90, 2, "sc: invalid max-stale specs near '" << item << "'");
 208                         sct->clearMaxStale();
 209                         /* leave the max-age alone */
 210                     }
 211                 }
 212             } else {
 213                 debugs(90, 2, "sc: invalid max-age specs near '" << item << "'");
 214                 sct->clearMaxAge();
 215             }
 216
 217             break;
 218         }
 219
 220         case SC_CONTENT:
 221
 222             if ( p && httpHeaderParseQuotedString(p, vlen, &sct->content_)) {
 223                 sct->setMask(SC_CONTENT,true); // ugly but saves a copy
 224             } else {
 225                 debugs(90, 2, "sc: invalid content= quoted string near '" << item << "'");
 226                 sct->clearContent();
 227             }
 228             break;
 229
 230         case SC_OTHER:
 231         default:
 232             break;
 233         }
 234     }
 235
 236     return sc->targets.head != NULL;
 237 }
 238
 239 HttpHdrSc::~HttpHdrSc()
 240 {
 241     if (targets.head) {
 242         dlink_node *sct = targets.head;
 243
 244         while (sct) {
 245             HttpHdrScTarget *t = static_cast<HttpHdrScTarget *>(sct->data);
 246             sct = sct->next;
 247             dlinkDelete (&t->node, &targets);
 248             delete t;
 249         }
 250     }
 251 }
 252
 253 HttpHdrSc::HttpHdrSc(const HttpHdrSc &sc)
 254 {
 255     dlink_node *node = sc.targets.head;
 256
 257     while (node) {
 258         HttpHdrScTarget *dupsct = new HttpHdrScTarget(*static_cast<HttpHdrScTarget *>(node->data));
 259         addTargetAtTail(dupsct);
 260         node = node->next;
 261     }
 262 }
 263
 264 void
 265 HttpHdrScTarget::packInto(Packer * p) const
 266 {
 267     http_hdr_sc_type flag;
 268     int pcount = 0;
 269     assert (p);
 270
 271     for (flag = SC_NO_STORE; flag < SC_ENUM_END; ++flag) {
 272         if (isSet(flag) && flag != SC_OTHER) {
 273
 274             /* print option name */
 275             packerPrintf(p, (pcount ? ", " SQUIDSTRINGPH : SQUIDSTRINGPH),
 276                          SQUIDSTRINGPRINT(ScFieldsInfo[flag].name));
 277
 278             /* handle options with values */
 279
 280             if (flag == SC_MAX_AGE)
 281                 packerPrintf(p, "=%d", (int) max_age);
 282
 283             if (flag == SC_CONTENT)
 284                 packerPrintf(p, "=\"" SQUIDSTRINGPH "\"", SQUIDSTRINGPRINT(content_));
 285
 286             ++pcount;
 287         }
 288     }
 289
 290     if (hasTarget())
 291         packerPrintf (p, ";" SQUIDSTRINGPH, SQUIDSTRINGPRINT(target));
 292 }
 293
 294 void
 295 HttpHdrSc::packInto(Packer * p) const
 296 {
 297     dlink_node *node;
 298     assert(p);
 299     node = targets.head;
 300
 301     while (node) {
 302         static_cast<HttpHdrScTarget *>(node->data)->packInto(p);
 303         node = node->next;
 304     }
 305 }
 306
 307 /* negative max_age will clean old max_Age setting */
 308 void
 309 HttpHdrSc::setMaxAge(char const *target, int max_age)
 310 {
 311     HttpHdrScTarget *sct = findTarget(target);
 312
 313     if (!sct) {
 314         sct = new HttpHdrScTarget(target);
 315         dlinkAddTail (sct, &sct->node, &targets);
 316     }
 317
 318     sct->maxAge(max_age);
 319 }
 320
 321 void
 322 HttpHdrSc::updateStats(StatHist * hist) const
 323 {
 324     dlink_node *sct = targets.head;
 325
 326     while (sct) {
 327         static_cast<HttpHdrScTarget *>(sct->data)->updateStats(hist);
 328         sct = sct->next;
 329     }
 330 }
 331
 332 void
 333 httpHdrScTargetStatDumper(StoreEntry * sentry, int idx, double val, double size, int count)
 334 {
 335     extern const HttpHeaderStat *dump_stat;     /* argh! */
 336     const int id = (int) val;
 337     const int valid_id = id >= 0 && id < SC_ENUM_END;
 338     const char *name = valid_id ? ScFieldsInfo[id].name.termedBuf() : "INVALID";
 339
 340     if (count || valid_id)
 341         storeAppendPrintf(sentry, "%2d\t %-20s\t %5d\t %6.2f\n",
 342                           id, name, count, xdiv(count, dump_stat->scParsedCount));
 343 }
 344
 345 void
 346 httpHdrScStatDumper(StoreEntry * sentry, int idx, double val, double size, int count)
 347 {
 348     extern const HttpHeaderStat *dump_stat;     /* argh! */
 349     const int id = (int) val;
 350     const int valid_id = id >= 0 && id < SC_ENUM_END;
 351     const char *name = valid_id ? ScFieldsInfo[id].name.termedBuf() : "INVALID";
 352
 353     if (count || valid_id)
 354         storeAppendPrintf(sentry, "%2d\t %-20s\t %5d\t %6.2f\n",
 355                           id, name, count, xdiv(count, dump_stat->scParsedCount));
 356 }
 357
 358 HttpHdrScTarget *
 359 HttpHdrSc::findTarget(const char *target)
 360 {
 361     dlink_node *node;
 362     node = targets.head;
 363
 364     while (node) {
 365         HttpHdrScTarget *sct = (HttpHdrScTarget *)node->data;
 366
 367         if (target && sct->target.size() > 0 && !strcmp(target, sct->target.termedBuf()))
 368             return sct;
 369         else if (!target && sct->target.size() == 0)
 370             return sct;
 371
 372         node = node->next;
 373     }
 374
 375     return NULL;
 376 }
 377
 378 HttpHdrScTarget *
 379 HttpHdrSc::getMergedTarget(const char *ourtarget)
 380 {
 381     HttpHdrScTarget *sctus = findTarget(ourtarget);
 382     HttpHdrScTarget *sctgeneric = findTarget(NULL);
 383
 384     if (sctgeneric || sctus) {
 385         HttpHdrScTarget *sctusable = new HttpHdrScTarget(NULL);
 386
 387         if (sctgeneric)
 388             sctusable->mergeWith(sctgeneric);
 389
 390         if (sctus)
 391             sctusable->mergeWith(sctus);
 392
 393         return sctusable;
 394     }
 395
 396     return NULL;
 397 }