src/esi/Context.h

   1 /*
   2  * Copyright (C) 1996-2014 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #ifndef SQUID_ESICONTEXT_H
  10 #define SQUID_ESICONTEXT_H
  11
  12 #include "clientStream.h"
  13 #include "err_type.h"
  14 #include "esi/Element.h"
  15 #include "esi/Parser.h"
  16 #include "http/StatusCode.h"
  17
  18 class ESIVarState;
  19 class ClientHttpRequest;
  20
  21 /* ESIContext */
  22
  23 class ESIContext : public esiTreeParent, public ESIParserClient
  24 {
  25     CBDATA_CLASS(ESIContext);
  26
  27 public:
  28     typedef RefCount<ESIContext> Pointer;
  29     ESIContext() :
  30             thisNode(NULL),
  31             http(NULL),
  32             errorpage(ERR_NONE),
  33             errorstatus(Http::scNone),
  34             errormessage(NULL),
  35             rep(NULL),
  36             outbound_offset(0),
  37             readpos(0),
  38             pos(0),
  39             varState(NULL),
  40             cachedASTInUse(false),
  41             reading_(true),
  42             processing(false) {
  43         memset(&flags, 0, sizeof(flags));
  44     }
  45
  46     ~ESIContext();
  47
  48     enum esiKick_t {
  49         ESI_KICK_FAILED,
  50         ESI_KICK_PENDING,
  51         ESI_KICK_SENT,
  52         ESI_KICK_INPROGRESS
  53     };
  54
  55     /* when esi processing completes */
  56     void provideData(ESISegment::Pointer, ESIElement *source);
  57     void fail (ESIElement *source, char const*anError = NULL);
  58     void startRead();
  59     void finishRead();
  60     bool reading() const;
  61     void setError();
  62     void setErrorMessage(char const *);
  63
  64     void addStackElement (ESIElement::Pointer element);
  65     void addLiteral (const char *s, int len);
  66
  67     void finishChildren ();
  68
  69     clientStreamNode *thisNode; /* our stream node */
  70     /* the request we are processing. HMM: cbdataReferencing this will result
  71      * in a circular reference, so we don't. Note: we are automatically freed
  72      * when it is, so thats ok. */
  73     ClientHttpRequest *http;
  74
  75     struct {
  76         int passthrough:1;
  77         int oktosend:1;
  78         int finished:1;
  79
  80         /* an error has occured, send full body replies
  81          * regardless. Note that we don't fail midstream
  82          * because we buffer until we can not fail
  83          */
  84         int error:1;
  85
  86         int finishedtemplate:1; /* we've read the entire template */
  87         int clientwantsdata:1; /* we need to satisfy a read request */
  88         int kicked:1; /* note on reentering the kick routine */
  89         int detached:1; /* our downstream has detached */
  90     } flags;
  91
  92     err_type errorpage; /* if we error what page to use */
  93     Http::StatusCode errorstatus; /* if we error, what code to return */
  94     char *errormessage; /* error to pass to error page */
  95     HttpReply *rep; /* buffered until we pass data downstream */
  96     ESISegment::Pointer buffered; /* unprocessed data - for whatever reason */
  97     ESISegment::Pointer incoming;
  98     /* processed data we are waiting to send, or for
  99      * potential errors to be resolved
 100      */
 101     ESISegment::Pointer outbound;
 102     ESISegment::Pointer outboundtail; /* our write segment */
 103     /* the offset to the next character to send -
 104      * non zero if we haven't sent the entire segment
 105      * for some reason
 106      */
 107     size_t outbound_offset;
 108     int64_t readpos; /* the logical position we are reading from */
 109     int64_t pos; /* the logical position of outbound_offset in the data stream */
 110
 111     class ParserState
 112     {
 113
 114     public:
 115         ESIElement::Pointer stack[10]; /* a stack of esi elements that are open */
 116         int stackdepth; /* self explanatory */
 117         ESIParser::Pointer theParser;
 118         ESIElement::Pointer top();
 119         void init (ESIParserClient *);
 120         bool inited() const;
 121         ParserState();
 122         void freeResources();
 123         void popAll();
 124         int parsing:1; /* libexpat is not reentrant on the same context */
 125
 126     private:
 127         bool inited_;
 128     }
 129
 130     parserState; /* todo factor this off somewhere else; */
 131     ESIVarState *varState;
 132     ESIElement::Pointer tree;
 133
 134     esiKick_t kick ();
 135     RefCount<ESIContext> cbdataLocker;
 136     bool failed() const {return flags.error != 0;}
 137
 138     bool cachedASTInUse;
 139
 140 private:
 141     void fail ();
 142     void freeResources();
 143     void fixupOutboundTail();
 144     void trimBlanks();
 145     size_t send ();
 146     bool reading_;
 147     void appendOutboundData(ESISegment::Pointer theData);
 148     esiProcessResult_t process ();
 149     void parse();
 150     void parseOneBuffer();
 151     void updateCachedAST();
 152     bool hasCachedAST() const;
 153     void getCachedAST();
 154     virtual void start(const char *el, const char **attr, size_t attrCount);
 155     virtual void end(const char *el);
 156     virtual void parserDefault (const char *s, int len);
 157     virtual void parserComment (const char *s);
 158     bool processing;
 159 };
 160
 161 #endif /* SQUID_ESICONTEXT_H */