[omniORB] omni and Apache

[Sai-Lai Lo]

It looks like my reply to Hany has not been CC to the list. So here it goes
again:

In one of our projects we have an apache module written to use omniORB.
The important point is when to call ORB_init.

In our apache module, the module dispatch structure looks like this:

static int initialised = 0;

// Spirit request content handler.
static int spirit_handler(request_rec *r)
{
  ....
  if (!initialised)
    {
      initialised = 1;
      int argc = 0;
      char** argv = NULL;
      CORBA::ORB_init(argc,argv,"omniORB3");
    }
  ....
}

// Here is the list of content handlers for the module.
static const handler_rec spirit_handlers[] =
{
    {"spirit-handler", spirit_handler},
    {NULL}
};

// We have no command directives for this module.
static const command_rec spirit_cmds[] =
{
    {NULL}
};

// And here is the list of callback routines.
module spirit_module =
{
    STANDARD_MODULE_STUFF,
    NULL,			// Initializer.
    NULL,			// Per-directory config.
    NULL,			// Directory config merger.
    NULL,			// Server config.
    NULL,			// Server config merger.
    spirit_cmds,                // Command table.
    spirit_handlers,		// Handler list.
    NULL,			// Filename-to-URI translation.
    NULL,			// Validate userid.
    NULL,			// Validate userid for this URI.
    NULL,			// Host address access.
    NULL,			// Check mime types.
    NULL,			// Any last minute fixes.
    NULL,			// Log.
#if MODULE_MAGIC_NUMBER >= 19970103
    NULL,			// Header parser.
#if MODULE_MAGIC_NUMBER >= 19970719
    NULL,			// Process initializer.
#if MODULE_MAGIC_NUMBER >= 19970728
    NULL,			// Process cleanup.
#if MODULE_MAGIC_NUMBER >= 19970902
    NULL			// Immediate handler.
#endif
#endif
#endif
#endif
};


Notice that ORB_init is called in the handler itself. That means it will be
called by the worker process that actually serve the http request. After
ORB_init is called, the ORB will spawn a few internal threads. If the
process call fork() soon afterwards, things will almost certainly not
work. By putting ORB_init in the handler, it is certain that the process
calling it will not be forking another process to do the work.

Regards,

Sai-Lai

>>>>> John Hedges writes:

> Hi Hany
> I believe there are problems with Apache and pthreads.
> Try a single threaded orb for your module (mico definately works and orbit looks like it ought to).

> Cheers

> John

> On Thursday, January 04, 2001 12:29 PM, Hany Greiss [SMTP:hany@peac.com] wrote:
>> 
>> 
>> Hello again,
>> 
>> Just to follow up on my previous e-mail regarding hanging on the call
>> to ORB_init from within an Apache module. I came across a suggestion to
>> insert tracing within the argc/argv parameters. When I did this the only
>> 
>> output I received was,
>> 
>> omniORB: strand Ripper: start.
>> 
>> It appears to hang at this point. Any ideas?
>> 
>> Thanks,
>> 
>> Hany
>> hany@portalsphere.com
>> 
>> 
>> 




-- 
Sai-Lai Lo                                   S.Lo@uk.research.att.com
AT&T Laboratories Cambridge           WWW:   http://www.uk.research.att.com 
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