general/6546: short pages (<4K) output from module::post_read_request are truncated to zero length

[David Hanney <dh...@digitalbrain.com>]

>Number:         6546
>Category:       general
>Synopsis:       short pages (<4K) output from module::post_read_request  are truncated to zero length
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Sun Sep 17 03:30:00 PDT 2000
>Closed-Date:
>Last-Modified:
>Originator:     dh@digitalbrain.com
>Release:        Apache/1.3.12 (Unix)
>Organization:
apache
>Environment:
server: {189} apache -v
Server version: Apache/1.3.12 (Unix)
Server built:   Jul 20 2000 16:19:47
server: {190} uname -a
FreeBSD server.brain 4.1-STABLE FreeBSD 4.1-STABLE #4: Wed Aug  9 13:25:31 BST 2000     root@server.brain:/usr/src/sys/compile/GENERIC  i386
server: {191}

>Description:
My C module registers as module::post_read_request
(all other module:: fields are NULL)

It is designed to sometimes processes the request completely (DONE) and
sometimes defer completely to Apache (DECLINE)

When it processes: the user only sees
the output if there is more than 4096 bytes of it
(including headers)
otherwise Apache outputs nothing!
>How-To-Repeat:
write a module that just registers through module::post_read_request
(all other module:: fields should be NULL)
post_read_request should ap_rwrite() a short message e.g. "Testing"
then return DONE

now try and see that message from a browser - it isn't there!

grow the test message to 4K and suddenly you can see it from the browser!
>Fix:
Is it related to buffering?
src/main/buff.c:#define DEFAULT_BUFSIZE (4096)

My current work around is to register the module at module::translate_handler
instead. This is later than I need - but it fixes the problem.
>Release-Note:
>Audit-Trail:
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