Received: (qmail 9880 invoked by uid 2012); 21 Oct 1997 22:22:57 -0000
Message-Id: <19971021222257.9879.qmail@hyperreal.org>
Date: 21 Oct 1997 22:22:57 -0000
From: David Chambers <davidc@flosun.salk.edu>
Reply-To: davidc@flosun.salk.edu
To: apbugs@hyperreal.org
Subject: Spurious mmap error messages?
X-Send-Pr-Version: 3.2

>Number:         1294
>Category:       os-sunos
>Synopsis:       Spurious mmap error messages?
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          closed
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Tue Oct 21 15:30:01 PDT 1997
>Last-Modified:  Thu Nov 13 20:00:59 PST 1997
>Originator:     davidc@flosun.salk.edu
>Organization:
>Release:        1.3b2
>Environment:
SunOS flosun 4.1.4 1 sun4c
gcc 2.7.2.2
>Description:
The server logs a [Crit] error for every file smaller than MMAP_THRESHOLD
 e.g. 
	[Tue Oct 21 14:01:36 1997] [crit] (2)No such file or directory: mmap_handler: mmap failed: /u3/www/docs/images/bullets/dots/yl_dot.gif

The client correctly displays the images or files, however.

Assuming this really is a bug, it must be a coding omission in http_core.c
around where the test if (mm==(caddr_t)-1) is made.  The code checks the
file size and if less than MMAP_THRESHOLD (only nonzero for SunOS) it sets
mm to (caddr_t) -1.  It then immediately checks mm to see if it's -1,
which it is, so it issues an error message.  Perhaps it should check the
file size again?

>How-To-Repeat:
It ought to occur on any SunOS platform
>Fix:
(see description) - I eliminated the messages by changing line 1686 of http_core.c
to read:
	if ((mm == (caddr_t)-1) && (r->finfo.st_size >= MMAP_THRESHOLD)) {

... but I'm not sure whether this is completely correct (what does block_alarms()
and unblock_alarms() do? :-%2
>Audit-Trail:
State-Changed-From-To: open-feedback
State-Changed-By: dgaudet
State-Changed-When: Tue Oct 21 18:01:32 PDT 1997
State-Changed-Why:
Waiting to see if the patch I sent does the job.

Dean

From: Dean Gaudet <dgaudet@arctic.org>
To: David Chambers <davidc@flosun.salk.edu>
Cc: apbugs@hyperreal.org
Subject: Re: os-sunos/1294: Spurious mmap error messages?
Date: Tue, 21 Oct 1997 18:01:42 -0700 (PDT)

 Yup this is a bug.  The block/unblock are important ... try this patch
 instead of your patch: 
 
 Dean
 
 Index: http_core.c
 ===================================================================
 RCS file: /export/home/cvs/apachen/src/main/http_core.c,v
 retrieving revision 1.125
 diff -u -r1.125 http_core.c
 --- http_core.c	1997/10/07 19:34:00	1.125
 +++ http_core.c	1997/10/22 00:59:36
 @@ -1686,8 +1686,10 @@
      if (mm == (caddr_t)-1) {
  	unblock_alarms();
  
 -	aplog_error(APLOG_MARK, APLOG_CRIT, r->server,
 -		    "mmap_handler: mmap failed: %s", r->filename);
 +	if (r->finfo.st_size >= MMAP_THRESHOLD) {
 +	    aplog_error(APLOG_MARK, APLOG_CRIT, r->server,
 +			"mmap_handler: mmap failed: %s", r->filename);
 +	}
  #endif
  
  	if (d->content_md5 & 1) {
 
 
State-Changed-From-To: feedback-closed
State-Changed-By: marc
State-Changed-When: Thu Nov 13 20:00:59 PST 1997
State-Changed-Why:
Patch applied to 1.3 development tree to fix the problem.

Thanks for the report.
>Unformatted: