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/*
* Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/*
* This module uses the magic of C++ static constructors to initialize the
* threads package at program start-up time.
*
* Note: Because of a bug in certain versions of "/usr/lib/c++rt0.o", you
* should _not_ enclose the body of this module in an "#ifdef _THREAD_SAFE"
* conditional.
*/
extern "C" void _thread_init(void);
/*
* First, we declare a class with a constructor.
*/
class _thread_init_invoker {
public:
_thread_init_invoker(); /* Constructor declaration. */
};
/*
* Here is the definition of the constructor. All it does is call the
* threads initialization function, "_thread_init".
*/
_thread_init_invoker::_thread_init_invoker()
{
_thread_init();
}
/*
* Here is a single, static instance of our "_thread_init_invoker" class.
* The mere existance of this instance will result in its constructor
* being called, automatically, at program start-up time.
*/
static _thread_init_invoker the_thread_init_invoker;
/*
* For the shared version of the threads library, the above is sufficient.
* But for the archive version of the library, we need a little bit more.
* Namely, we must arrange for this particular module to be pulled in from
* the archive library at link time. To accomplish that, we define and
* initialize a variable, "_thread_autoinit_dummy_decl". This variable is
* referenced (as an extern) from libc/stdlib/exit.c. This will always
* create a need for this module, ensuring that it is present in the
* executable.
*
* We know that, if the user does _anything_ at all with threads, then the
* "uthread_init.c" module will be linked in. That is the case because
* "uthread_init.c" is the module that defines all of the global variables
* used by the threads library. The presence of "uthread_init.c" will, in
* turn, force this module to be linked in. And the presence of this module
* in the executable will result in the constructor being invoked, and
* "_thread_init" being called.
*/
extern "C" int _thread_autoinit_dummy_decl; /* Declare with "C" linkage */
int _thread_autoinit_dummy_decl = 0;
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