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34 #ifndef SQUID_ICAPMODXACT_H
35 #define SQUID_ICAPMODXACT_H
38 #include "adaptation/icap/Xaction.h"
39 #include "adaptation/icap/InOut.h"
40 #include "adaptation/icap/Launcher.h"
43 * ICAPModXact implements ICAP REQMOD and RESPMOD transaction using
44 * ICAPXaction as the base. The ICAPModXact receives a virgin HTTP message
45 * from an ICAP vecoring point, (a.k.a., initiator), communicates with the
46 * ICAP server, and sends the adapted HTTP message headers back.
47 * Virgin/adapted HTTP message body is reveived/sent using BodyPipe
48 * interface. The initiator (or its associate) is expected to send and/or
49 * receive the HTTP body.
53 class ChunkedCodingParser
;
60 // estimated future presence and size of something (e.g., HTTP body)
66 SizedEstimate(); // not expected by default
67 void expect(int64_t aSize
); // expect with any, even unknown size
68 bool expected() const;
70 /* other members can be accessed iff expected() */
72 bool knownSize() const;
73 uint64_t size() const; // can be accessed iff knownSize()
76 enum { dtUnexpected
= -2, dtUnknown
= -1 };
77 int64_t theData
; // combines expectation and size info to save RAM
80 // Virgin body may be used for two activities: (a) writing preview or prime
81 // body to the ICAP server and (b) sending the body back in the echo mode.
82 // Both activities use the same BodyPipe and may be active at the same time.
83 // This class is used to maintain the state of body writing or sending
84 // activity and to coordinate consumption of the shared virgin body buffer.
91 void plan(); // the activity may happen; do not consume at or above offset
92 void disable(); // the activity wont continue; no consumption restrictions
94 bool active() const { return theState
== stActive
; }
95 bool disabled() const { return theState
== stDisabled
; }
97 // methods below require active()
99 uint64_t offset() const; // the absolute beginning of not-yet-acted-on data
100 void progress(size_t size
); // note processed body bytes
103 int64_t theStart
; // unprocessed virgin body data offset
105 typedef enum { stUndecided
, stActive
, stDisabled
} State
;
110 // maintains preview-related sizes
116 Preview(); // disabled
117 void enable(size_t anAd
); // enabled with advertised size
118 bool enabled() const;
120 /* other members can be accessed iff enabled() */
122 size_t ad() const; // advertised preview size
123 size_t debt() const; // remains to write
124 bool done() const; // wrote everything
125 bool ieof() const; // premature EOF
127 void wrote(size_t size
, bool wroteEof
);
132 enum State
{ stDisabled
, stWriting
, stIeof
, stDone
} theState
;
135 class ModXact
: public Xaction
, public BodyProducer
, public BodyConsumer
139 ModXact(Adaptation::Initiator
*anInitiator
, HttpMsg
*virginHeader
, HttpRequest
*virginCause
, ServiceRep::Pointer
&s
);
141 // BodyProducer methods
142 virtual void noteMoreBodySpaceAvailable(BodyPipe::Pointer
);
143 virtual void noteBodyConsumerAborted(BodyPipe::Pointer
);
145 // BodyConsumer methods
146 virtual void noteMoreBodyDataAvailable(BodyPipe::Pointer
);
147 virtual void noteBodyProductionEnded(BodyPipe::Pointer
);
148 virtual void noteBodyProducerAborted(BodyPipe::Pointer
);
151 virtual void handleCommConnected();
152 virtual void handleCommWrote(size_t size
);
153 virtual void handleCommRead(size_t size
);
154 void handleCommWroteHeaders();
155 void handleCommWroteBody();
158 void noteServiceReady();
165 // bypasses exceptions if needed and possible
166 virtual void callException(const std::exception
&e
);
169 virtual void start();
171 /// locates the request, either as a cause or as a virgin message itself
172 const HttpRequest
&virginRequest() const; // Must always be available
174 void estimateVirginBody();
175 void makeAdaptedBodyPipe(const char *what
);
177 void waitForService();
179 // will not send anything [else] on the adapted pipe
180 bool doneSending() const;
184 void writePreviewBody();
185 void writePrimeBody();
186 void writeSomeBody(const char *label
, size_t size
);
190 virtual bool doneReading() const { return commEof
|| state
.doneParsing(); }
191 virtual bool doneWriting() const { return state
.doneWriting(); }
193 size_t virginContentSize(const VirginBodyAct
&act
) const;
194 const char *virginContentData(const VirginBodyAct
&act
) const;
195 bool virginBodyEndReached(const VirginBodyAct
&act
) const;
197 void makeRequestHeaders(MemBuf
&buf
);
198 void makeUsernameHeader(const HttpRequest
*request
, MemBuf
&buf
);
199 void addLastRequestChunk(MemBuf
&buf
);
200 void openChunk(MemBuf
&buf
, size_t chunkSize
, bool ieof
);
201 void closeChunk(MemBuf
&buf
);
202 void virginConsume();
203 void finishNullOrEmptyBodyPreview(MemBuf
&buf
);
205 void decideOnPreview();
206 void decideOnRetries();
207 bool shouldAllow204();
208 bool canBackupEverything() const;
210 void prepBackup(size_t expectedSize
);
211 void backup(const MemBuf
&buf
);
216 void parseIcapHead();
217 void parseHttpHead();
218 bool parseHead(HttpMsg
*head
);
220 void decideOnParsingBody();
222 void maybeAllocateHttpMsg();
224 void handle100Continue();
225 bool validate200Ok();
227 void handle204NoContent();
228 void handleUnknownScode();
230 void bypassFailure();
233 void disableBypass(const char *reason
, bool includeGroupBypass
);
238 virtual bool doneAll() const;
239 virtual void swanSong();
241 void stopReceiving();
242 void stopSending(bool nicely
);
243 void stopWriting(bool nicely
);
247 virtual void fillPendingStatus(MemBuf
&buf
) const;
248 virtual void fillDoneStatus(MemBuf
&buf
) const;
249 virtual bool fillVirginHttpHeader(MemBuf
&) const;
252 void packHead(MemBuf
&httpBuf
, const HttpMsg
*head
);
253 void encapsulateHead(MemBuf
&icapBuf
, const char *section
, MemBuf
&httpBuf
, const HttpMsg
*head
);
254 bool gotEncapsulated(const char *section
) const;
255 void checkConsuming();
257 virtual void finalizeLogInfo();
259 SizedEstimate virginBody
;
260 VirginBodyAct virginBodyWriting
; // virgin body writing state
261 VirginBodyAct virginBodySending
; // virgin body sending state
262 uint64_t virginConsumed
; // virgin data consumed so far
263 Preview preview
; // use for creating (writing) the preview
265 ChunkedCodingParser
*bodyParser
; // ICAP response body parser
267 bool canStartBypass
; // enables bypass of transaction failures
268 bool protectGroupBypass
; // protects ServiceGroup-wide bypass of failures
270 uint64_t replyBodySize
; ///< dechunked ICAP reply body size
272 int adaptHistoryId
; ///< adaptation history slot reservation
282 bool serviceWaiting
; // waiting for ICAP service options
283 bool allowedPostview204
; // mmust handle 204 No Content outside preview
285 // will not write anything [else] to the ICAP server connection
286 bool doneWriting() const { return writing
== writingReallyDone
; }
288 // will not use virgin.body_pipe
289 bool doneConsumingVirgin() const {
290 return writing
>= writingAlmostDone
291 && (sending
== sendingAdapted
|| sending
== sendingDone
);
294 // parsed entire ICAP response from the ICAP server
295 bool doneParsing() const { return parsing
== psDone
; }
297 // is parsing ICAP or HTTP headers read from the ICAP server
298 bool parsingHeaders() const {
299 return parsing
== psIcapHeader
||
300 parsing
== psHttpHeader
;
303 enum Parsing
{ psIcapHeader
, psHttpHeader
, psBody
, psDone
} parsing
;
305 // measures ICAP request writing progress
306 enum Writing
{ writingInit
, writingConnect
, writingHeaders
,
307 writingPreview
, writingPaused
, writingPrime
,
308 writingAlmostDone
, // waiting for the last write() call to finish
312 enum Sending
{ sendingUndecided
, sendingVirgin
, sendingAdapted
,
317 CBDATA_CLASS2(ModXact
);
320 // An Launcher that stores ModXact construction info and
321 // creates ModXact when needed
322 class ModXactLauncher
: public Launcher
325 ModXactLauncher(Adaptation::Initiator
*anInitiator
, HttpMsg
*virginHeader
, HttpRequest
*virginCause
, Adaptation::ServicePointer s
);
328 virtual Xaction
*createXaction();
330 virtual void swanSong();
332 /// starts or stops transaction accounting in ICAP history
333 void updateHistory(bool start
);
338 CBDATA_CLASS2(ModXactLauncher
);
343 } // namespace Adaptation
345 #endif /* SQUID_ICAPMOD_XACT_H */