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Re: HTHost: Pipeline recovery inherently broken [patch]

From: Richard Atterer <richard@list03.atterer.net>
Date: Sat, 22 Feb 2003 20:23:27 +0100
To: www-lib@w3.org
Message-ID: <20030222192327.GA4226@nenya.lan>

Hello,

here is your libwww patch of the day! :-)

My previous patch to disable pipeline recovery did not fix the issue
entirely - the replacement patch below does.

The fix for the "off by one" error I mentioned earlier enables some code
which was previously "dead", i.e. never called. That code contains another
bug: Because it is called in response to the connection being closed, it
must discard the persistent socket of the dropped connection with
HTHost_clearChannel().

Cheers,

  Richard

-- 
  __   _
  |_) /|  Richard Atterer     |  CS student at the Technische  |  GnuPG key:
  | \/¯|  http://atterer.net  |  Universität München, Germany  |  0x888354F7
  ¯ '` ¯

--- HTHost.c.orig	2003-02-19 01:12:17.000000000 +0100
+++ HTHost.c	2003-02-22 20:05:47.000000000 +0100
@@ -31,7 +31,7 @@
 #define TCP_IDLE_ACTIVE     60000L /* Active TTL in ms on an idle connection */
 
 #define MAX_PIPES		50   /* maximum number of pipelined requests */
-#define MAX_HOST_RECOVER	1	      /* Max number of auto recovery */
+#define MAX_HOST_RECOVER	0	      /* Max number of auto recovery */
 #define DEFAULT_DELAY		30	  /* Default write flush delay in ms */
 
 struct _HTInputStream {
@@ -824,8 +824,10 @@
 	/*
 	**  First check that we haven't already recovered more than we want
 	*/
-	if (host->recovered > MAX_HOST_RECOVER) {
+	if (host->recovered >= MAX_HOST_RECOVER) {
 	    HTTRACE(CORE_TRACE, "Host recover %p already %d times - not doing it anymore\n" _ host _ host->recovered);
+	    HTChannel_setSemaphore(host->channel, 0);
+	    HTHost_clearChannel(host, HT_INTERRUPTED);
 	    return NO;
 	}
 
@@ -958,7 +960,7 @@
     case HT_TP_SINGLE:
 	return count <= 0;
     case HT_TP_PIPELINE:
-	return (host->recovered < MAX_HOST_RECOVER) ?
+	return (host->recovered < MAX_HOST_RECOVER || MAX_HOST_RECOVER==0) ?
 	    (count < MaxPipelinedRequests) : (count <= 0);
     case HT_TP_INTERLEAVE:
 	return YES;
Received on Saturday, 22 February 2003 15:03:56 GMT

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