Received: (qmail 64688 invoked by uid 501); 9 May 2001 10:47:54 -0000
Message-Id: <20010509104754.64667.qmail@apache.org>
Date: 9 May 2001 10:47:54 -0000
From: Giuseppe D'Ambrosio <boltthrower@libero.it>
Reply-To: boltthrower@libero.it
To: submit@bugz.apache.org
Subject: map type rnd: doesn't  give a random result
X-Send-Pr-Version: 3.110

>Number:         7689
>Category:       mod_rewrite
>Synopsis:       map type rnd: doesn't  give a random result
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Quarter:
>Keywords:
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Wed May 09 03:50:02 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     boltthrower@libero.it
>Release:        1.3.12
>Organization:
apache
>Environment:
windows NT 4.0 serv.pack 4
compiled with MSVC 6 or binaries from the official distribution
>Description:
my problem was: setting a local proxy to joke a friend so that he couldn't get - *randomly* - a page;

I've worked with mod_rewrite in this way (shortened and out of peculiarities):

snippet from httpd.config
----
RewriteEngine on
RewriteLog logs/rewrite.log
RewriteLogLevel 5
RewriteMap map1 rnd:conf/map1.txt
RewriteCond ${map1:random10} ^1$
RewriteRule (testcond$) ??x1
----


the map map1.txt is
----
random10  1|2|3|4|5|6|7|8|9|10
----

but in this way I always get the first case ("1" or whatever I put as first case)



note:
1)I also submitted this on the new-httpd list some weeks ago but got no answer;
2)the httpd compiled from the 2.0.14a tree *crashes* with this config. (I think in do_expand)



>How-To-Repeat:
you can test repeatedly on a local URL such as
http://127.0.0.1/testcond and check the rewrite.log file

since this is probabilistic you can also modify the map1.txt adding a large number of possibilities;

I've tryed more than 50 times with 100 cases (choices) and got ever the first (that's enough..)


>Fix:
I've got it to work only replacing the call to rand() with a locally-implemented function mt_rand()  (eg. from http://www.math.keio.ac.jp/matumoto/)

or, at first with something like  sin(time()) as raw random generator
>Release-Note:
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