crt1.c

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/* LINTLIBRARY */
/*-
 * Copyright 1996-1998 John D. Polstra.
 * Copyright 2012 Konstantin Belousov <kib@FreeBSD.org>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */
 
#include <stdlib.h>
 
#include <sys/cdefs.h>
 
extern int main(int, char **);
 
extern void (*__preinit_array_start[])(int, char **, char **) __hidden;
extern void (*__preinit_array_end[])(int, char **, char **) __hidden;
extern void (*__init_array_start[])(int, char **, char **) __hidden;
extern void (*__init_array_end[])(int, char **, char **) __hidden;
extern void (*__fini_array_start[])(void) __hidden;
extern void (*__fini_array_end[])(void) __hidden;
extern void _fini(void) __hidden;
extern void _init(void) __hidden;
 
char **environ;
const char *__progname = "";
 
static void
finalizer(void)
{
        void (*fn)(void);
        size_t array_size, n;
 
        array_size = __fini_array_end - __fini_array_start;
        for (n = array_size; n > 0; n--) {
                fn = __fini_array_start[n - 1];
                if ((uintptr_t)fn != 0 && (uintptr_t)fn != 1)
                        (fn)();
        }
        _fini();
}
 
static inline void
handle_static_init(int argc, char **argv, char **env)
{
        void (*fn)(int, char **, char **);
        size_t array_size, n;
 
        atexit(finalizer);
 
        array_size = __preinit_array_end - __preinit_array_start;
        for (n = 0; n < array_size; n++) {
                fn = __preinit_array_start[n];
                if ((uintptr_t)fn != 0 && (uintptr_t)fn != 1)
                        fn(argc, argv, env);
        }
        _init();
        array_size = __init_array_end - __init_array_start;
        for (n = 0; n < array_size; n++) {
                fn = __init_array_start[n];
                if ((uintptr_t)fn != 0 && (uintptr_t)fn != 1)
                        fn(argc, argv, env);
        }
}
 
static inline void
handle_argv(int argc, char *argv[], char **env)
{
        const char *s;
 
        if (environ == NULL)
                environ = env;
        if (argc > 0 && argv[0] != NULL) {
                __progname = argv[0];
                for (s = __progname; *s != '\0'; s++) {
                        if (*s == '/')
                                __progname = s + 1;
                }
        }
}
 
void
_start(char **ap)
{
        int status;
        int argc = 0;
        char **argv = NULL;
        char **env = NULL;
 
        argc = *(long *)(void *)ap;
        argv = ap + 1;
        //env = ap + 2 + argc;
        handle_argv(argc, argv, env);
 
        handle_static_init(argc, argv, env);
 
        status = main(argc, argv);
 
        finalizer();
 
        exit(status);
}