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From Joe Lewis <>
Subject Re: Per-server config issue
Date Fri, 23 Feb 2007 20:33:22 GMT
John David Duncan wrote:
> const char *config_server_thing(cmd_parms *cmd, void *m, char *arg) {
> }
> So far, so good. But here's the problem: In this function, I should be 
> able to cast the pointer, m, back to the struct srv that was 
> initialized earlier.
> srv_conf = (struct srv *) m;
> But after lots of debugging, I find that:
> 1) The pointer m is not equal to the pointer that was returned from 
> the initialization function.
> 2) m does not hold a copy of the data structure that was initialized.
> 3) And m is also not equal to the value of
> ap_get_module_config(cmd->server->module_config, &my_module)
> Finally, as a work-around, I decided to use:
> srv_conf = (struct srv *) 
> ap_get_module_config(cmd->server->module_config, &my_module);
> instead of:
> srv_conf = (struct srv *) m;

The void *m parameter is only set if the function is being called in a 
<Directory> block, in which case it will be assigned to that directory 
block's configuration that you create, not the servers' configuration 
structure. If it is a server directive (as yours is in the examples you 
provided) this parameter should be NULL.

I have a few functions that are both directory specific and also server 
specific (used in both circumstances), and to prevent a redesign of the 
wheel, I typically check for NULL on that parameter, and if it is NULL, 
I reassign it to the cmd->server->module_config option - giving me a 
valid configuration structure as I created both. Then I am free to do 
what I want with it.

Joseph Lewis <>
"Divide the fire, and you will sooner put it out." - Publius Syrus

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