3 * DEBUG: section 72 Peer Digest Routines
4 * AUTHOR: Alex Rousskov
6 * SQUID Web Proxy Cache http://www.squid-cache.org/
7 * ----------------------------------------------------------
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18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License as published by
20 * the Free Software Foundation; either version 2 of the License, or
21 * (at your option) any later version.
23 * This program is distributed in the hope that it will be useful,
24 * but WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 * GNU General Public License for more details.
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30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
36 #include "CacheDigest.h"
37 #include "CachePeer.h"
41 #include "HttpReply.h"
42 #include "HttpRequest.h"
44 #include "MemObject.h"
45 #include "neighbors.h"
46 #include "mime_header.h"
47 #include "PeerDigest.h"
48 #include "SquidTime.h"
50 #include "store_key_md5.h"
51 #include "StoreClient.h"
56 /* local prototypes */
57 static time_t peerDigestIncDelay(const PeerDigest
* pd
);
58 static time_t peerDigestNewDelay(const StoreEntry
* e
);
59 static void peerDigestSetCheck(PeerDigest
* pd
, time_t delay
);
60 static void peerDigestClean(PeerDigest
*);
61 static EVH peerDigestCheck
;
62 static void peerDigestRequest(PeerDigest
* pd
);
63 static STCB peerDigestHandleReply
;
64 static int peerDigestFetchReply(void *, char *, ssize_t
);
65 int peerDigestSwapInHeaders(void *, char *, ssize_t
);
66 int peerDigestSwapInCBlock(void *, char *, ssize_t
);
67 int peerDigestSwapInMask(void *, char *, ssize_t
);
68 static int peerDigestFetchedEnough(DigestFetchState
* fetch
, char *buf
, ssize_t size
, const char *step_name
);
69 static void peerDigestFetchStop(DigestFetchState
* fetch
, char *buf
, const char *reason
);
70 static void peerDigestFetchAbort(DigestFetchState
* fetch
, char *buf
, const char *reason
);
71 static void peerDigestReqFinish(DigestFetchState
* fetch
, char *buf
, int, int, int, const char *reason
, int err
);
72 static void peerDigestPDFinish(DigestFetchState
* fetch
, int pcb_valid
, int err
);
73 static void peerDigestFetchFinish(DigestFetchState
* fetch
, int err
);
74 static void peerDigestFetchSetStats(DigestFetchState
* fetch
);
75 static int peerDigestSetCBlock(PeerDigest
* pd
, const char *buf
);
76 static int peerDigestUseful(const PeerDigest
* pd
);
79 Version
const CacheDigestVer
= { 5, 3 };
81 #define StoreDigestCBlockSize sizeof(StoreDigestCBlock)
83 /* min interval for requesting digests from a given peer */
84 static const time_t PeerDigestReqMinGap
= 5 * 60; /* seconds */
85 /* min interval for requesting digests (cumulative request stream) */
86 static const time_t GlobDigestReqMinGap
= 1 * 60; /* seconds */
90 static time_t pd_last_req_time
= 0; /* last call to Check */
92 /* initialize peer digest */
94 peerDigestInit(PeerDigest
* pd
, CachePeer
* p
)
98 memset(pd
, 0, sizeof(*pd
));
101 * Lock on to the peer here. The corresponding cbdataReferenceDone()
102 * is in peerDigestDestroy().
104 pd
->peer
= cbdataReference(p
);
105 /* if peer disappears, we will know it's name */
108 pd
->times
.initialized
= squid_curtime
;
112 peerDigestClean(PeerDigest
* pd
)
117 cacheDigestDestroy(pd
->cd
);
122 CBDATA_CLASS_INIT(PeerDigest
);
125 PeerDigest::operator new (size_t)
127 CBDATA_INIT_TYPE(PeerDigest
);
128 PeerDigest
*result
= cbdataAlloc(PeerDigest
);
133 PeerDigest::operator delete (void *address
)
135 PeerDigest
*t
= static_cast<PeerDigest
*>(address
);
139 /* allocate new peer digest, call Init, and lock everything */
141 peerDigestCreate(CachePeer
* p
)
147 peerDigestInit(pd
, p
);
149 /* XXX This does not look right, and the same thing again in the caller */
150 return cbdataReference(pd
);
153 /* call Clean and free/unlock everything */
155 peerDigestDestroy(PeerDigest
* pd
)
159 void * peerTmp
= pd
->peer
;
163 * We locked the peer in peerDigestInit(), this is
164 * where we unlock it. If the peer is still valid,
165 * tell it that the digest is gone.
167 if (cbdataReferenceValidDone(peerTmp
, &p
))
168 peerNoteDigestGone((CachePeer
*)p
);
175 /* called by peer to indicate that somebody actually needs this digest */
177 peerDigestNeeded(PeerDigest
* pd
)
180 assert(!pd
->flags
.needed
);
183 pd
->flags
.needed
= true;
184 pd
->times
.needed
= squid_curtime
;
185 peerDigestSetCheck(pd
, 0); /* check asap */
188 /* currently we do not have a reason to disable without destroying */
190 /* disables peer for good */
192 peerDigestDisable(PeerDigest
* pd
)
194 debugs(72, 2, "peerDigestDisable: peer " << pd
->host
.buf() << " disabled for good");
195 pd
->times
.disabled
= squid_curtime
;
196 pd
->times
.next_check
= -1; /* never */
197 pd
->flags
.usable
= 0;
200 cacheDigestDestroy(pd
->cd
);
204 /* we do not destroy the pd itself to preserve its "history" and stats */
209 /* increment retry delay [after an unsuccessful attempt] */
211 peerDigestIncDelay(const PeerDigest
* pd
)
214 return pd
->times
.retry_delay
> 0 ?
215 2 * pd
->times
.retry_delay
: /* exponential backoff */
216 PeerDigestReqMinGap
; /* minimal delay */
219 /* artificially increases Expires: setting to avoid race conditions
220 * returns the delay till that [increased] expiration time */
222 peerDigestNewDelay(const StoreEntry
* e
)
227 return e
->expires
+ PeerDigestReqMinGap
- squid_curtime
;
229 return PeerDigestReqMinGap
;
232 /* registers next digest verification */
234 peerDigestSetCheck(PeerDigest
* pd
, time_t delay
)
236 eventAdd("peerDigestCheck", peerDigestCheck
, pd
, (double) delay
, 1);
237 pd
->times
.next_check
= squid_curtime
+ delay
;
238 debugs(72, 3, "peerDigestSetCheck: will check peer " << pd
->host
<< " in " << delay
<< " secs");
242 * called when peer is about to disappear or have already disappeared
245 peerDigestNotePeerGone(PeerDigest
* pd
)
247 if (pd
->flags
.requested
) {
248 debugs(72, 2, "peerDigest: peer " << pd
->host
<< " gone, will destroy after fetch.");
249 /* do nothing now, the fetching chain will notice and take action */
251 debugs(72, 2, "peerDigest: peer " << pd
->host
<< " is gone, destroying now.");
252 peerDigestDestroy(pd
);
256 /* callback for eventAdd() (with peer digest locked)
257 * request new digest if our copy is too old or if we lack one;
258 * schedule next check otherwise */
260 peerDigestCheck(void *data
)
262 PeerDigest
*pd
= (PeerDigest
*)data
;
265 assert(!pd
->flags
.requested
);
267 pd
->times
.next_check
= 0; /* unknown */
269 if (!cbdataReferenceValid(pd
->peer
)) {
270 peerDigestNotePeerGone(pd
);
274 debugs(72, 3, "peerDigestCheck: peer " << pd
->peer
->host
<< ":" << pd
->peer
->http_port
);
275 debugs(72, 3, "peerDigestCheck: time: " << squid_curtime
<<
276 ", last received: " << (long int) pd
->times
.received
<< " (" <<
277 std::showpos
<< (int) (squid_curtime
- pd
->times
.received
) << ")");
279 /* decide when we should send the request:
280 * request now unless too close to other requests */
281 req_time
= squid_curtime
;
285 if (req_time
- pd
->times
.received
< PeerDigestReqMinGap
) {
286 debugs(72, 2, "peerDigestCheck: " << pd
->host
<<
287 ", avoiding close peer requests (" <<
288 (int) (req_time
- pd
->times
.received
) << " < " <<
289 (int) PeerDigestReqMinGap
<< " secs).");
291 req_time
= pd
->times
.received
+ PeerDigestReqMinGap
;
295 if (req_time
- pd_last_req_time
< GlobDigestReqMinGap
) {
296 debugs(72, 2, "peerDigestCheck: " << pd
->host
<<
297 ", avoiding close requests (" <<
298 (int) (req_time
- pd_last_req_time
) << " < " <<
299 (int) GlobDigestReqMinGap
<< " secs).");
301 req_time
= pd_last_req_time
+ GlobDigestReqMinGap
;
304 if (req_time
<= squid_curtime
)
305 peerDigestRequest(pd
); /* will set pd->flags.requested */
307 peerDigestSetCheck(pd
, req_time
- squid_curtime
);
310 CBDATA_TYPE(DigestFetchState
);
312 /* ask store for a digest */
314 peerDigestRequest(PeerDigest
* pd
)
316 CachePeer
*p
= pd
->peer
;
317 StoreEntry
*e
, *old_e
;
319 const cache_key
*key
;
321 DigestFetchState
*fetch
= NULL
;
322 StoreIOBuffer tempBuffer
;
324 pd
->req_result
= NULL
;
325 pd
->flags
.requested
= true;
327 /* compute future request components */
330 url
= xstrdup(p
->digest_url
);
332 url
= internalRemoteUri(p
->host
, p
->http_port
,
333 "/squid-internal-periodic/", StoreDigestFileName
);
335 req
= HttpRequest::CreateFromUrl(url
);
339 key
= storeKeyPublicByRequest(req
);
341 debugs(72, 2, "peerDigestRequest: " << url
<< " key: " << storeKeyText(key
));
343 /* add custom headers */
344 assert(!req
->header
.len
);
346 req
->header
.putStr(HDR_ACCEPT
, StoreDigestMimeStr
);
348 req
->header
.putStr(HDR_ACCEPT
, "text/html");
351 xstrncpy(req
->login
, p
->login
, MAX_LOGIN_SZ
);
353 /* create fetch state structure */
354 CBDATA_INIT_TYPE(DigestFetchState
);
356 fetch
= cbdataAlloc(DigestFetchState
);
358 fetch
->request
= HTTPMSGLOCK(req
);
360 fetch
->pd
= cbdataReference(pd
);
364 fetch
->state
= DIGEST_READ_REPLY
;
366 /* update timestamps */
367 fetch
->start_time
= squid_curtime
;
369 pd
->times
.requested
= squid_curtime
;
371 pd_last_req_time
= squid_curtime
;
373 req
->flags
.cachable
= true;
375 /* the rest is based on clientProcessExpired() */
376 req
->flags
.refresh
= true;
378 old_e
= fetch
->old_entry
= Store::Root().get(key
);
381 debugs(72, 5, "peerDigestRequest: found old entry");
384 old_e
->createMemObject(url
, url
);
386 fetch
->old_sc
= storeClientListAdd(old_e
, fetch
);
389 e
= fetch
->entry
= storeCreateEntry(url
, url
, req
->flags
, req
->method
);
390 assert(EBIT_TEST(e
->flags
, KEY_PRIVATE
));
391 fetch
->sc
= storeClientListAdd(e
, fetch
);
392 /* set lastmod to trigger IMS request if possible */
395 e
->lastmod
= old_e
->lastmod
;
397 /* push towards peer cache */
398 debugs(72, 3, "peerDigestRequest: forwarding to fwdStart...");
400 FwdState::fwdStart(Comm::ConnectionPointer(), e
, req
);
402 tempBuffer
.offset
= 0;
404 tempBuffer
.length
= SM_PAGE_SIZE
;
406 tempBuffer
.data
= fetch
->buf
;
408 storeClientCopy(fetch
->sc
, e
, tempBuffer
,
409 peerDigestHandleReply
, fetch
);
412 /* Handle the data copying .. */
415 * This routine handles the copy data and then redirects the
416 * copy to a bunch of subfunctions depending upon the copy state.
417 * It also tracks the buffer offset and "seen", since I'm actually
418 * not interested in rewriting everything to suit my little idea.
421 peerDigestHandleReply(void *data
, StoreIOBuffer receivedData
)
423 DigestFetchState
*fetch
= (DigestFetchState
*)data
;
425 digest_read_state_t prevstate
;
428 assert(fetch
->pd
&& receivedData
.data
);
429 /* The existing code assumes that the received pointer is
430 * where we asked the data to be put
432 assert(fetch
->buf
+ fetch
->bufofs
== receivedData
.data
);
434 /* Update the buffer size */
435 fetch
->bufofs
+= receivedData
.length
;
437 assert(fetch
->bufofs
<= SM_PAGE_SIZE
);
439 /* If we've fetched enough, return */
441 if (peerDigestFetchedEnough(fetch
, fetch
->buf
, fetch
->bufofs
, "peerDigestHandleReply"))
444 /* Call the right function based on the state */
445 /* (Those functions will update the state if needed) */
447 /* Give us a temporary reference. Some of the calls we make may
448 * try to destroy the fetch structure, and we like to know if they
451 fetch
= cbdataReference(fetch
);
453 /* Repeat this loop until we're out of data OR the state changes */
454 /* (So keep going if the state has changed and we still have data */
456 prevstate
= fetch
->state
;
458 switch (fetch
->state
) {
460 case DIGEST_READ_REPLY
:
461 retsize
= peerDigestFetchReply(fetch
, fetch
->buf
, fetch
->bufofs
);
464 case DIGEST_READ_HEADERS
:
465 retsize
= peerDigestSwapInHeaders(fetch
, fetch
->buf
, fetch
->bufofs
);
468 case DIGEST_READ_CBLOCK
:
469 retsize
= peerDigestSwapInCBlock(fetch
, fetch
->buf
, fetch
->bufofs
);
472 case DIGEST_READ_MASK
:
473 retsize
= peerDigestSwapInMask(fetch
, fetch
->buf
, fetch
->bufofs
);
476 case DIGEST_READ_NONE
:
479 case DIGEST_READ_DONE
:
484 fatal("Bad digest transfer mode!\n");
491 * The returned size indicates how much of the buffer was read -
492 * so move the remainder of the buffer to the beginning
493 * and update the bufofs / bufsize
495 newsize
= fetch
->bufofs
- retsize
;
497 memmove(fetch
->buf
, fetch
->buf
+ retsize
, fetch
->bufofs
- newsize
);
499 fetch
->bufofs
= newsize
;
501 } while (cbdataReferenceValid(fetch
) && prevstate
!= fetch
->state
&& fetch
->bufofs
> 0);
503 /* Update the copy offset */
504 fetch
->offset
+= receivedData
.length
;
506 /* Schedule another copy */
507 if (cbdataReferenceValid(fetch
)) {
508 StoreIOBuffer tempBuffer
;
509 tempBuffer
.offset
= fetch
->offset
;
510 tempBuffer
.length
= SM_PAGE_SIZE
- fetch
->bufofs
;
511 tempBuffer
.data
= fetch
->buf
+ fetch
->bufofs
;
512 storeClientCopy(fetch
->sc
, fetch
->entry
, tempBuffer
,
513 peerDigestHandleReply
, fetch
);
517 /* Get rid of our reference, we've finished with it for now */
518 cbdataReferenceDone(fetch
);
521 /* wait for full http headers to be received then parse them */
523 * This routine handles parsing the reply line.
524 * If the reply line indicates an OK, the same data is thrown
525 * to SwapInHeaders(). If the reply line is a NOT_MODIFIED,
526 * we simply stop parsing.
529 peerDigestFetchReply(void *data
, char *buf
, ssize_t size
)
531 DigestFetchState
*fetch
= (DigestFetchState
*)data
;
532 PeerDigest
*pd
= fetch
->pd
;
535 assert(!fetch
->offset
);
537 assert(fetch
->state
== DIGEST_READ_REPLY
);
539 if (peerDigestFetchedEnough(fetch
, buf
, size
, "peerDigestFetchReply"))
542 if ((hdr_size
= headersEnd(buf
, size
))) {
544 HttpReply
const *reply
= fetch
->entry
->getReply();
546 assert (reply
->sline
.status
!= 0);
547 status
= reply
->sline
.status
;
548 debugs(72, 3, "peerDigestFetchReply: " << pd
->host
<< " status: " << status
<<
549 ", expires: " << (long int) reply
->expires
<< " (" << std::showpos
<<
550 (int) (reply
->expires
- squid_curtime
) << ")");
552 /* this "if" is based on clientHandleIMSReply() */
554 if (status
== HTTP_NOT_MODIFIED
) {
555 /* our old entry is fine */
556 assert(fetch
->old_entry
);
558 if (!fetch
->old_entry
->mem_obj
->request
)
559 fetch
->old_entry
->mem_obj
->request
= HTTPMSGLOCK(fetch
->entry
->mem_obj
->request
);
561 assert(fetch
->old_entry
->mem_obj
->request
);
563 HttpReply
*old_rep
= (HttpReply
*) fetch
->old_entry
->getReply();
565 old_rep
->updateOnNotModified(reply
);
567 fetch
->old_entry
->timestampsSet();
569 /* get rid of 304 reply */
570 storeUnregister(fetch
->sc
, fetch
->entry
, fetch
);
572 fetch
->entry
->unlock();
574 fetch
->entry
= fetch
->old_entry
;
576 fetch
->old_entry
= NULL
;
578 /* preserve request -- we need its size to update counters */
579 /* requestUnlink(r); */
580 /* fetch->entry->mem_obj->request = NULL; */
581 } else if (status
== HTTP_OK
) {
582 /* get rid of old entry if any */
584 if (fetch
->old_entry
) {
585 debugs(72, 3, "peerDigestFetchReply: got new digest, releasing old one");
586 storeUnregister(fetch
->old_sc
, fetch
->old_entry
, fetch
);
587 fetch
->old_entry
->releaseRequest();
588 fetch
->old_entry
->unlock();
589 fetch
->old_entry
= NULL
;
592 /* some kind of a bug */
593 peerDigestFetchAbort(fetch
, buf
, httpStatusLineReason(&reply
->sline
));
594 return -1; /* XXX -1 will abort stuff in ReadReply! */
597 /* must have a ready-to-use store entry if we got here */
598 /* can we stay with the old in-memory digest? */
599 if (status
== HTTP_NOT_MODIFIED
&& fetch
->pd
->cd
) {
600 peerDigestFetchStop(fetch
, buf
, "Not modified");
601 fetch
->state
= DIGEST_READ_DONE
;
603 fetch
->state
= DIGEST_READ_HEADERS
;
606 /* need more data, do we have space? */
608 if (size
>= SM_PAGE_SIZE
)
609 peerDigestFetchAbort(fetch
, buf
, "reply header too big");
612 /* We don't want to actually ack that we've handled anything,
613 * otherwise SwapInHeaders() won't get the reply line .. */
617 /* fetch headers from disk, pass on to SwapInCBlock */
619 peerDigestSwapInHeaders(void *data
, char *buf
, ssize_t size
)
621 DigestFetchState
*fetch
= (DigestFetchState
*)data
;
624 assert(fetch
->state
== DIGEST_READ_HEADERS
);
626 if (peerDigestFetchedEnough(fetch
, buf
, size
, "peerDigestSwapInHeaders"))
629 assert(!fetch
->offset
);
631 if ((hdr_size
= headersEnd(buf
, size
))) {
632 assert(fetch
->entry
->getReply());
633 assert (fetch
->entry
->getReply()->sline
.status
!= 0);
635 if (fetch
->entry
->getReply()->sline
.status
!= HTTP_OK
) {
636 debugs(72, DBG_IMPORTANT
, "peerDigestSwapInHeaders: " << fetch
->pd
->host
<<
637 " status " << fetch
->entry
->getReply()->sline
.status
<<
640 peerDigestFetchAbort(fetch
, buf
, "internal status error");
644 fetch
->state
= DIGEST_READ_CBLOCK
;
645 return hdr_size
; /* Say how much data we read */
647 /* need more data, do we have space? */
649 if (size
>= SM_PAGE_SIZE
) {
650 peerDigestFetchAbort(fetch
, buf
, "stored header too big");
653 return 0; /* We need to read more to parse .. */
657 fatal("peerDigestSwapInHeaders() - shouldn't get here!\n");
658 return 0; /* keep gcc happy */
662 peerDigestSwapInCBlock(void *data
, char *buf
, ssize_t size
)
664 DigestFetchState
*fetch
= (DigestFetchState
*)data
;
666 assert(fetch
->state
== DIGEST_READ_CBLOCK
);
668 if (peerDigestFetchedEnough(fetch
, buf
, size
, "peerDigestSwapInCBlock"))
671 if (size
>= (ssize_t
)StoreDigestCBlockSize
) {
672 PeerDigest
*pd
= fetch
->pd
;
674 assert(pd
&& fetch
->entry
->getReply());
676 if (peerDigestSetCBlock(pd
, buf
)) {
677 /* XXX: soon we will have variable header size */
678 /* switch to CD buffer and fetch digest guts */
680 assert(pd
->cd
->mask
);
681 fetch
->state
= DIGEST_READ_MASK
;
682 return StoreDigestCBlockSize
;
684 peerDigestFetchAbort(fetch
, buf
, "invalid digest cblock");
688 /* need more data, do we have space? */
690 if (size
>= SM_PAGE_SIZE
) {
691 peerDigestFetchAbort(fetch
, buf
, "digest cblock too big");
694 return 0; /* We need more data */
698 fatal("peerDigestSwapInCBlock(): shouldn't get here!\n");
699 return 0; /* keep gcc happy */
703 peerDigestSwapInMask(void *data
, char *buf
, ssize_t size
)
705 DigestFetchState
*fetch
= (DigestFetchState
*)data
;
709 assert(pd
->cd
&& pd
->cd
->mask
);
712 * NOTENOTENOTENOTENOTE: buf doesn't point to pd->cd->mask anymore!
713 * we need to do the copy ourselves!
715 memcpy(pd
->cd
->mask
+ fetch
->mask_offset
, buf
, size
);
717 /* NOTE! buf points to the middle of pd->cd->mask! */
719 if (peerDigestFetchedEnough(fetch
, NULL
, size
, "peerDigestSwapInMask"))
722 fetch
->mask_offset
+= size
;
724 if (fetch
->mask_offset
>= pd
->cd
->mask_size
) {
725 debugs(72, 2, "peerDigestSwapInMask: Done! Got " <<
726 fetch
->mask_offset
<< ", expected " << pd
->cd
->mask_size
);
727 assert(fetch
->mask_offset
== pd
->cd
->mask_size
);
728 assert(peerDigestFetchedEnough(fetch
, NULL
, 0, "peerDigestSwapInMask"));
729 return -1; /* XXX! */
731 /* We always read everything, so return so */
735 fatal("peerDigestSwapInMask(): shouldn't get here!\n");
736 return 0; /* keep gcc happy */
740 peerDigestFetchedEnough(DigestFetchState
* fetch
, char *buf
, ssize_t size
, const char *step_name
)
742 PeerDigest
*pd
= NULL
;
743 const char *host
= "<unknown>"; /* peer host */
744 const char *reason
= NULL
; /* reason for completion */
745 const char *no_bug
= NULL
; /* successful completion if set */
746 const int pdcb_valid
= cbdataReferenceValid(fetch
->pd
);
747 const int pcb_valid
= cbdataReferenceValid(fetch
->pd
->peer
);
749 /* test possible exiting conditions (the same for most steps!)
750 * cases marked with '?!' should not happen */
753 if (!(pd
= fetch
->pd
))
754 reason
= "peer digest disappeared?!";
756 #if DONT /* WHY NOT? /HNO */
758 else if (!cbdataReferenceValid(pd
))
759 reason
= "invalidated peer digest?!";
764 host
= pd
->host
.termedBuf();
767 debugs(72, 6, step_name
<< ": peer " << host
<< ", offset: " <<
768 fetch
->offset
<< " size: " << size
<< ".");
770 /* continue checking (with pd and host known and valid) */
773 if (!cbdataReferenceValid(pd
->peer
))
774 reason
= "peer disappeared";
776 reason
= "swap failure";
777 else if (!fetch
->entry
)
778 reason
= "swap aborted?!";
779 else if (EBIT_TEST(fetch
->entry
->flags
, ENTRY_ABORTED
))
780 reason
= "swap aborted";
783 /* continue checking (maybe-successful eof case) */
784 if (!reason
&& !size
) {
786 reason
= "null digest?!";
787 else if (fetch
->mask_offset
!= (int)pd
->cd
->mask_size
)
788 reason
= "premature end of digest?!";
789 else if (!peerDigestUseful(pd
))
790 reason
= "useless digest";
792 reason
= no_bug
= "success";
795 /* finish if we have a reason */
797 const int level
= strstr(reason
, "?!") ? 1 : 3;
798 debugs(72, level
, "" << step_name
<< ": peer " << host
<< ", exiting after '" << reason
<< "'");
799 peerDigestReqFinish(fetch
, buf
,
800 1, pdcb_valid
, pcb_valid
, reason
, !no_bug
);
803 assert(pdcb_valid
&& pcb_valid
);
806 return reason
!= NULL
;
809 /* call this when all callback data is valid and fetch must be stopped but
810 * no error has occurred (e.g. we received 304 reply and reuse old digest) */
812 peerDigestFetchStop(DigestFetchState
* fetch
, char *buf
, const char *reason
)
815 debugs(72, 2, "peerDigestFetchStop: peer " << fetch
->pd
->host
<< ", reason: " << reason
);
816 peerDigestReqFinish(fetch
, buf
, 1, 1, 1, reason
, 0);
819 /* call this when all callback data is valid but something bad happened */
821 peerDigestFetchAbort(DigestFetchState
* fetch
, char *buf
, const char *reason
)
824 debugs(72, 2, "peerDigestFetchAbort: peer " << fetch
->pd
->host
<< ", reason: " << reason
);
825 peerDigestReqFinish(fetch
, buf
, 1, 1, 1, reason
, 1);
828 /* complete the digest transfer, update stats, unlock/release everything */
830 peerDigestReqFinish(DigestFetchState
* fetch
, char *buf
,
831 int fcb_valid
, int pdcb_valid
, int pcb_valid
,
832 const char *reason
, int err
)
836 /* must go before peerDigestPDFinish */
839 fetch
->pd
->flags
.requested
= false;
840 fetch
->pd
->req_result
= reason
;
843 /* schedule next check if peer is still out there */
845 PeerDigest
*pd
= fetch
->pd
;
848 pd
->times
.retry_delay
= peerDigestIncDelay(pd
);
849 peerDigestSetCheck(pd
, pd
->times
.retry_delay
);
851 pd
->times
.retry_delay
= 0;
852 peerDigestSetCheck(pd
, peerDigestNewDelay(fetch
->entry
));
856 /* note: order is significant */
858 peerDigestFetchSetStats(fetch
);
861 peerDigestPDFinish(fetch
, pcb_valid
, err
);
864 peerDigestFetchFinish(fetch
, err
);
867 /* destroys digest if peer disappeared
868 * must be called only when fetch and pd cbdata are valid */
870 peerDigestPDFinish(DigestFetchState
* fetch
, int pcb_valid
, int err
)
872 PeerDigest
*pd
= fetch
->pd
;
873 const char *host
= pd
->host
.termedBuf();
875 pd
->times
.received
= squid_curtime
;
876 pd
->times
.req_delay
= fetch
->resp_time
;
877 kb_incr(&pd
->stats
.sent
.kbytes
, (size_t) fetch
->sent
.bytes
);
878 kb_incr(&pd
->stats
.recv
.kbytes
, (size_t) fetch
->recv
.bytes
);
879 pd
->stats
.sent
.msgs
+= fetch
->sent
.msg
;
880 pd
->stats
.recv
.msgs
+= fetch
->recv
.msg
;
883 debugs(72, DBG_IMPORTANT
, "" << (pcb_valid
? "temporary " : "" ) << "disabling (" << pd
->req_result
<< ") digest from " << host
);
886 cacheDigestDestroy(pd
->cd
);
890 pd
->flags
.usable
= false;
893 peerDigestNotePeerGone(pd
);
897 pd
->flags
.usable
= true;
899 /* XXX: ugly condition, but how? */
901 if (fetch
->entry
->store_status
== STORE_OK
)
902 debugs(72, 2, "re-used old digest from " << host
);
904 debugs(72, 2, "received valid digest from " << host
);
907 cbdataReferenceDone(fetch
->pd
);
910 /* free fetch state structures
911 * must be called only when fetch cbdata is valid */
913 peerDigestFetchFinish(DigestFetchState
* fetch
, int err
)
915 assert(fetch
->entry
&& fetch
->request
);
917 if (fetch
->old_entry
) {
918 debugs(72, 3, "peerDigestFetchFinish: deleting old entry");
919 storeUnregister(fetch
->old_sc
, fetch
->old_entry
, fetch
);
920 fetch
->old_entry
->releaseRequest();
921 fetch
->old_entry
->unlock();
922 fetch
->old_entry
= NULL
;
925 /* update global stats */
926 kb_incr(&statCounter
.cd
.kbytes_sent
, (size_t) fetch
->sent
.bytes
);
928 kb_incr(&statCounter
.cd
.kbytes_recv
, (size_t) fetch
->recv
.bytes
);
930 statCounter
.cd
.msgs_sent
+= fetch
->sent
.msg
;
932 statCounter
.cd
.msgs_recv
+= fetch
->recv
.msg
;
934 /* unlock everything */
935 storeUnregister(fetch
->sc
, fetch
->entry
, fetch
);
937 fetch
->entry
->unlock();
939 HTTPMSGUNLOCK(fetch
->request
);
943 assert(fetch
->pd
== NULL
);
948 /* calculate fetch stats after completion */
950 peerDigestFetchSetStats(DigestFetchState
* fetch
)
953 assert(fetch
->entry
&& fetch
->request
);
955 mem
= fetch
->entry
->mem_obj
;
958 /* XXX: outgoing numbers are not precise */
959 /* XXX: we must distinguish between 304 hits and misses here */
960 fetch
->sent
.bytes
= fetch
->request
->prefixLen();
961 /* XXX: this is slightly wrong: we don't KNOW that the entire memobject
962 * was fetched. We only know how big it is
964 fetch
->recv
.bytes
= mem
->size();
965 fetch
->sent
.msg
= fetch
->recv
.msg
= 1;
966 fetch
->expires
= fetch
->entry
->expires
;
967 fetch
->resp_time
= squid_curtime
- fetch
->start_time
;
969 debugs(72, 3, "peerDigestFetchFinish: recv " << fetch
->recv
.bytes
<<
970 " bytes in " << (int) fetch
->resp_time
<< " secs");
972 debugs(72, 3, "peerDigestFetchFinish: expires: " <<
973 (long int) fetch
->expires
<< " (" << std::showpos
<<
974 (int) (fetch
->expires
- squid_curtime
) << "), lmt: " <<
975 std::noshowpos
<< (long int) fetch
->entry
->lastmod
<< " (" <<
976 std::showpos
<< (int) (fetch
->entry
->lastmod
- squid_curtime
) <<
982 peerDigestSetCBlock(PeerDigest
* pd
, const char *buf
)
984 StoreDigestCBlock cblock
;
986 const char *host
= pd
->host
.termedBuf();
988 memcpy(&cblock
, buf
, sizeof(cblock
));
989 /* network -> host conversions */
990 cblock
.ver
.current
= ntohs(cblock
.ver
.current
);
991 cblock
.ver
.required
= ntohs(cblock
.ver
.required
);
992 cblock
.capacity
= ntohl(cblock
.capacity
);
993 cblock
.count
= ntohl(cblock
.count
);
994 cblock
.del_count
= ntohl(cblock
.del_count
);
995 cblock
.mask_size
= ntohl(cblock
.mask_size
);
996 debugs(72, 2, "got digest cblock from " << host
<< "; ver: " <<
997 (int) cblock
.ver
.current
<< " (req: " << (int) cblock
.ver
.required
<<
1000 debugs(72, 2, "\t size: " <<
1001 cblock
.mask_size
<< " bytes, e-cnt: " <<
1002 cblock
.count
<< ", e-util: " <<
1003 xpercentInt(cblock
.count
, cblock
.capacity
) << "%" );
1004 /* check version requirements (both ways) */
1006 if (cblock
.ver
.required
> CacheDigestVer
.current
) {
1007 debugs(72, DBG_IMPORTANT
, "" << host
<< " digest requires version " <<
1008 cblock
.ver
.required
<< "; have: " << CacheDigestVer
.current
);
1013 if (cblock
.ver
.current
< CacheDigestVer
.required
) {
1014 debugs(72, DBG_IMPORTANT
, "" << host
<< " digest is version " <<
1015 cblock
.ver
.current
<< "; we require: " <<
1016 CacheDigestVer
.required
);
1021 /* check consistency */
1022 if (cblock
.ver
.required
> cblock
.ver
.current
||
1023 cblock
.mask_size
<= 0 || cblock
.capacity
<= 0 ||
1024 cblock
.bits_per_entry
<= 0 || cblock
.hash_func_count
<= 0) {
1025 debugs(72, DBG_CRITICAL
, "" << host
<< " digest cblock is corrupted.");
1029 /* check consistency further */
1030 if ((size_t)cblock
.mask_size
!= cacheDigestCalcMaskSize(cblock
.capacity
, cblock
.bits_per_entry
)) {
1031 debugs(72, DBG_CRITICAL
, host
<< " digest cblock is corrupted " <<
1032 "(mask size mismatch: " << cblock
.mask_size
<< " ? " <<
1033 cacheDigestCalcMaskSize(cblock
.capacity
, cblock
.bits_per_entry
)
1038 /* there are some things we cannot do yet */
1039 if (cblock
.hash_func_count
!= CacheDigestHashFuncCount
) {
1040 debugs(72, DBG_CRITICAL
, "" << host
<< " digest: unsupported #hash functions: " <<
1041 cblock
.hash_func_count
<< " ? " << CacheDigestHashFuncCount
<< ".");
1046 * no cblock bugs below this point
1048 /* check size changes */
1049 if (pd
->cd
&& cblock
.mask_size
!= (ssize_t
)pd
->cd
->mask_size
) {
1050 debugs(72, 2, host
<< " digest changed size: " << cblock
.mask_size
<<
1051 " -> " << pd
->cd
->mask_size
);
1052 freed_size
= pd
->cd
->mask_size
;
1053 cacheDigestDestroy(pd
->cd
);
1058 debugs(72, 2, "creating " << host
<< " digest; size: " << cblock
.mask_size
<< " (" <<
1059 std::showpos
<< (int) (cblock
.mask_size
- freed_size
) << ") bytes");
1060 pd
->cd
= cacheDigestCreate(cblock
.capacity
, cblock
.bits_per_entry
);
1062 if (cblock
.mask_size
>= freed_size
)
1063 kb_incr(&statCounter
.cd
.memory
, cblock
.mask_size
- freed_size
);
1067 /* these assignments leave us in an inconsistent state until we finish reading the digest */
1068 pd
->cd
->count
= cblock
.count
;
1069 pd
->cd
->del_count
= cblock
.del_count
;
1074 peerDigestUseful(const PeerDigest
* pd
)
1076 /* TODO: we should calculate the prob of a false hit instead of bit util */
1077 const int bit_util
= cacheDigestBitUtil(pd
->cd
);
1079 if (bit_util
> 65) {
1080 debugs(72, DBG_CRITICAL
, "Warning: " << pd
->host
<<
1081 " peer digest has too many bits on (" << bit_util
<< "%%).");
1090 saneDiff(time_t diff
)
1092 return abs((int) diff
) > squid_curtime
/ 2 ? 0 : diff
;
1096 peerDigestStatsReport(const PeerDigest
* pd
, StoreEntry
* e
)
1098 #define f2s(flag) (pd->flags.flag ? "yes" : "no")
1099 #define appendTime(tm) storeAppendPrintf(e, "%s\t %10ld\t %+d\t %+d\n", \
1100 ""#tm, (long int)pd->times.tm, \
1101 saneDiff(pd->times.tm - squid_curtime), \
1102 saneDiff(pd->times.tm - pd->times.initialized))
1106 const char *host
= pd
->host
.termedBuf();
1107 storeAppendPrintf(e
, "\npeer digest from %s\n", host
);
1109 cacheDigestGuessStatsReport(&pd
->stats
.guess
, e
, host
);
1111 storeAppendPrintf(e
, "\nevent\t timestamp\t secs from now\t secs from init\n");
1112 appendTime(initialized
);
1114 appendTime(requested
);
1115 appendTime(received
);
1116 appendTime(next_check
);
1118 storeAppendPrintf(e
, "peer digest state:\n");
1119 storeAppendPrintf(e
, "\tneeded: %3s, usable: %3s, requested: %3s\n",
1120 f2s(needed
), f2s(usable
), f2s(requested
));
1121 storeAppendPrintf(e
, "\n\tlast retry delay: %d secs\n",
1122 (int) pd
->times
.retry_delay
);
1123 storeAppendPrintf(e
, "\tlast request response time: %d secs\n",
1124 (int) pd
->times
.req_delay
);
1125 storeAppendPrintf(e
, "\tlast request result: %s\n",
1126 pd
->req_result
? pd
->req_result
: "(none)");
1128 storeAppendPrintf(e
, "\npeer digest traffic:\n");
1129 storeAppendPrintf(e
, "\trequests sent: %d, volume: %d KB\n",
1130 pd
->stats
.sent
.msgs
, (int) pd
->stats
.sent
.kbytes
.kb
);
1131 storeAppendPrintf(e
, "\treplies recv: %d, volume: %d KB\n",
1132 pd
->stats
.recv
.msgs
, (int) pd
->stats
.recv
.kbytes
.kb
);
1134 storeAppendPrintf(e
, "\npeer digest structure:\n");
1137 cacheDigestReport(pd
->cd
, host
, e
);
1139 storeAppendPrintf(e
, "\tno in-memory copy\n");