1 files changed, 89 insertions, 0 deletions
diff --git a/lib/libc_r/uthread/uthread_autoinit.cc b/lib/libc_r/uthread/uthread_autoinit.cc
new file mode 100644
index 0000000..b04caff
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+++ b/lib/libc_r/uthread/uthread_autoinit.cc
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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 AUTHOR 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.
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * 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;