src/esi/Context.h

   1 /*
   2  *
   3  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   4  * ----------------------------------------------------------
   5  *
   6  *  Squid is the result of efforts by numerous individuals from
   7  *  the Internet community; see the CONTRIBUTORS file for full
   8  *  details.   Many organizations have provided support for Squid's
   9  *  development; see the SPONSORS file for full details.  Squid is
  10  *  Copyrighted (C) 2001 by the Regents of the University of
  11  *  California; see the COPYRIGHT file for full details.  Squid
  12  *  incorporates software developed and/or copyrighted by other
  13  *  sources; see the CREDITS file for full details.
  14  *
  15  *  This program is free software; you can redistribute it and/or modify
  16  *  it under the terms of the GNU General Public License as published by
  17  *  the Free Software Foundation; either version 2 of the License, or
  18  *  (at your option) any later version.
  19  *
  20  *  This program is distributed in the hope that it will be useful,
  21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *  GNU General Public License for more details.
  24  *
  25  *  You should have received a copy of the GNU General Public License
  26  *  along with this program; if not, write to the Free Software
  27  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  28  *
  29  * Copyright (c) 2003, Robert Collins <robertc@squid-cache.org>
  30  */
  31
  32 #ifndef SQUID_ESICONTEXT_H
  33 #define SQUID_ESICONTEXT_H
  34
  35 #include "esi/Parser.h"
  36 #include "esi/Element.h"
  37 #include "clientStream.h"
  38 #include "err_type.h"
  39 #include "HttpStatusCode.h"
  40
  41 class ESIVarState;
  42 class ClientHttpRequest;
  43
  44 /* ESIContext */
  45
  46 class ESIContext : public esiTreeParent, public ESIParserClient
  47 {
  48
  49 public:
  50     typedef RefCount<ESIContext> Pointer;
  51     void *operator new (size_t byteCount);
  52     void operator delete (void *address);
  53     ESIContext():reading_(true) {}
  54
  55     ~ESIContext();
  56
  57     enum esiKick_t {
  58         ESI_KICK_FAILED,
  59         ESI_KICK_PENDING,
  60         ESI_KICK_SENT,
  61         ESI_KICK_INPROGRESS
  62     };
  63
  64     /* when esi processing completes */
  65     void provideData(ESISegment::Pointer, ESIElement *source);
  66     void fail (ESIElement *source, char const*anError = NULL);
  67     void startRead();
  68     void finishRead();
  69     bool reading() const;
  70     void setError();
  71     void setErrorMessage(char const *);
  72
  73     void addStackElement (ESIElement::Pointer element);
  74     void addLiteral (const char *s, int len);
  75
  76     void finishChildren ();
  77
  78     clientStreamNode *thisNode; /* our stream node */
  79     /* the request we are processing. HMM: cbdataReferencing this will result
  80      * in a circular reference, so we don't. Note: we are automatically freed
  81      * when it is, so thats ok. */
  82     ClientHttpRequest *http;
  83
  84     struct {
  85         int passthrough:1;
  86         int oktosend:1;
  87         int finished:1;
  88
  89         /* an error has occured, send full body replies
  90          * regardless. Note that we don't fail midstream
  91          * because we buffer until we can not fail
  92          */
  93         int error:1;
  94
  95         int finishedtemplate:1; /* we've read the entire template */
  96         int clientwantsdata:1; /* we need to satisfy a read request */
  97         int kicked:1; /* note on reentering the kick routine */
  98         int detached:1; /* our downstream has detached */
  99     } flags;
 100
 101     err_type errorpage; /* if we error what page to use */
 102     http_status errorstatus; /* if we error, what code to return */
 103     char *errormessage; /* error to pass to error page */
 104     HttpReply *rep; /* buffered until we pass data downstream */
 105     ESISegment::Pointer buffered; /* unprocessed data - for whatever reason */
 106     ESISegment::Pointer incoming;
 107     /* processed data we are waiting to send, or for
 108      * potential errors to be resolved
 109      */
 110     ESISegment::Pointer outbound;
 111     ESISegment::Pointer outboundtail; /* our write segment */
 112     /* the offset to the next character to send -
 113      * non zero if we haven't sent the entire segment
 114      * for some reason
 115      */
 116     size_t outbound_offset;
 117     int64_t readpos; /* the logical position we are reading from */
 118     int64_t pos; /* the logical position of outbound_offset in the data stream */
 119
 120     class ParserState
 121     {
 122
 123     public:
 124         ESIElement::Pointer stack[10]; /* a stack of esi elements that are open */
 125         int stackdepth; /* self explanatory */
 126         ESIParser::Pointer theParser;
 127         ESIElement::Pointer top();
 128         void init (ESIParserClient *);
 129         bool inited() const;
 130         ParserState();
 131         void freeResources();
 132         void popAll();
 133         int parsing:1; /* libexpat is not reentrant on the same context */
 134
 135     private:
 136         bool inited_;
 137     }
 138
 139     parserState; /* todo factor this off somewhere else; */
 140     ESIVarState *varState;
 141     ESIElement::Pointer tree;
 142
 143     esiKick_t kick ();
 144     RefCount<ESIContext> cbdataLocker;
 145     bool failed() const {return flags.error != 0;}
 146
 147     bool cachedASTInUse;
 148
 149 private:
 150     void fail ();
 151     void freeResources();
 152     void fixupOutboundTail();
 153     void trimBlanks();
 154     size_t send ();
 155     bool reading_;
 156     void appendOutboundData(ESISegment::Pointer theData);
 157     esiProcessResult_t process ();
 158     void parse();
 159     void parseOneBuffer();
 160     void updateCachedAST();
 161     bool hasCachedAST() const;
 162     void getCachedAST();
 163     virtual void start(const char *el, const char **attr, size_t attrCount);
 164     virtual void end(const char *el);
 165     virtual void parserDefault (const char *s, int len);
 166     virtual void parserComment (const char *s);
 167     bool processing;
 168
 169     CBDATA_CLASS(ESIContext);
 170 };
 171
 172 #endif /* SQUID_ESICONTEXT_H */