src/esi/Context.h

   1 /*
   2  * Copyright (C) 1996-2017 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/forward.h"
  17 #include "http/StatusCode.h"
  18
  19 class ESIVarState;
  20 class ClientHttpRequest;
  21
  22 /* ESIContext */
  23
  24 class ESIContext : public esiTreeParent, public ESIParserClient
  25 {
  26     CBDATA_CLASS(ESIContext);
  27
  28 public:
  29     typedef RefCount<ESIContext> Pointer;
  30     ESIContext() :
  31         thisNode(NULL),
  32         http(NULL),
  33         errorpage(ERR_NONE),
  34         errorstatus(Http::scNone),
  35         errormessage(NULL),
  36         rep(NULL),
  37         outbound_offset(0),
  38         readpos(0),
  39         pos(0),
  40         varState(NULL),
  41         cachedASTInUse(false),
  42         reading_(true),
  43         processing(false) {
  44         memset(&flags, 0, sizeof(flags));
  45     }
  46
  47     ~ESIContext();
  48
  49     enum esiKick_t {
  50         ESI_KICK_FAILED,
  51         ESI_KICK_PENDING,
  52         ESI_KICK_SENT,
  53         ESI_KICK_INPROGRESS
  54     };
  55
  56     /* when esi processing completes */
  57     void provideData(ESISegment::Pointer, ESIElement *source);
  58     void fail (ESIElement *source, char const*anError = NULL);
  59     void startRead();
  60     void finishRead();
  61     bool reading() const;
  62     void setError();
  63     void setErrorMessage(char const *);
  64
  65     void addStackElement (ESIElement::Pointer element);
  66     void addLiteral (const char *s, int len);
  67
  68     void finishChildren ();
  69
  70     clientStreamNode *thisNode; /* our stream node */
  71     /* the request we are processing. HMM: cbdataReferencing this will result
  72      * in a circular reference, so we don't. Note: we are automatically freed
  73      * when it is, so thats ok. */
  74     ClientHttpRequest *http;
  75
  76     struct {
  77         int passthrough:1;
  78         int oktosend:1;
  79         int finished:1;
  80
  81         /* an error has occured, send full body replies
  82          * regardless. Note that we don't fail midstream
  83          * because we buffer until we can not fail
  84          */
  85         int error:1;
  86
  87         int finishedtemplate:1; /* we've read the entire template */
  88         int clientwantsdata:1; /* we need to satisfy a read request */
  89         int kicked:1; /* note on reentering the kick routine */
  90         int detached:1; /* our downstream has detached */
  91     } flags;
  92
  93     err_type errorpage; /* if we error what page to use */
  94     Http::StatusCode errorstatus; /* if we error, what code to return */
  95     char *errormessage; /* error to pass to error page */
  96     HttpReplyPointer rep; /* buffered until we pass data downstream */
  97     ESISegment::Pointer buffered; /* unprocessed data - for whatever reason */
  98     ESISegment::Pointer incoming;
  99     /* processed data we are waiting to send, or for
 100      * potential errors to be resolved
 101      */
 102     ESISegment::Pointer outbound;
 103     ESISegment::Pointer outboundtail; /* our write segment */
 104     /* the offset to the next character to send -
 105      * non zero if we haven't sent the entire segment
 106      * for some reason
 107      */
 108     size_t outbound_offset;
 109     int64_t readpos; /* the logical position we are reading from */
 110     int64_t pos; /* the logical position of outbound_offset in the data stream */
 111
 112     class ParserState
 113     {
 114
 115     public:
 116         ESIElement::Pointer stack[10]; /* a stack of esi elements that are open */
 117         int stackdepth; /* self explanatory */
 118         ESIParser::Pointer theParser;
 119         ESIElement::Pointer top();
 120         void init (ESIParserClient *);
 121         bool inited() const;
 122         ParserState();
 123         void freeResources();
 124         void popAll();
 125         int parsing:1; /* libexpat is not reentrant on the same context */
 126
 127     private:
 128         bool inited_;
 129     }
 130
 131     parserState; /* todo factor this off somewhere else; */
 132     ESIVarState *varState;
 133     ESIElement::Pointer tree;
 134
 135     esiKick_t kick ();
 136     RefCount<ESIContext> cbdataLocker;
 137     bool failed() const {return flags.error != 0;}
 138
 139     bool cachedASTInUse;
 140
 141 private:
 142     void fail ();
 143     void freeResources();
 144     void fixupOutboundTail();
 145     void trimBlanks();
 146     size_t send ();
 147     bool reading_;
 148     void appendOutboundData(ESISegment::Pointer theData);
 149     esiProcessResult_t process ();
 150     void parse();
 151     void parseOneBuffer();
 152     void updateCachedAST();
 153     bool hasCachedAST() const;
 154     void getCachedAST();
 155     virtual void start(const char *el, const char **attr, size_t attrCount);
 156     virtual void end(const char *el);
 157     virtual void parserDefault (const char *s, int len);
 158     virtual void parserComment (const char *s);
 159     bool processing;
 160 };
 161
 162 #endif /* SQUID_ESICONTEXT_H */
 163