glibc/sysdeps/unix/start.c
2012-02-09 23:18:22 +00:00

96 lines
3.0 KiB
C

/* Copyright (C) 1991, 93, 1995-1998, 2000, 2012 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
In addition to the permissions in the GNU Lesser General Public
License, the Free Software Foundation gives you unlimited
permission to link the compiled version of this file with other
programs, and to distribute those programs without any restriction
coming from the use of this file. (The GNU Lesser General Public
License restrictions do apply in other respects; for example, they
cover modification of the file, and distribution when not linked
into another program.)
Note that people who make modified versions of this file are not
obligated to grant this special exception for their modified
versions; it is their choice whether to do so. The GNU Lesser
General Public License gives permission to release a modified
version without this exception; this exception also makes it
possible to release a modified version which carries forward this
exception.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <sysdep.h> /* In case it wants to define anything. */
/* The first piece of initialized data. */
int __data_start = 0;
weak_alias (__data_start, data_start)
#ifdef DUMMIES
#define ARG_DUMMIES DUMMIES,
#define DECL_DUMMIES int DUMMIES;
#else
#define ARG_DUMMIES
#define DECL_DUMMIES
#endif
extern void __libc_init (int argc, char **argv, char **envp);
extern int main (int argc, char **argv, char **envp);
/* Not a prototype because it gets called strangely. */
static void start1();
#ifndef HAVE__start
/* N.B.: It is important that this be the first function.
This file is the first thing in the text section. */
void
_start ()
{
start1 ();
}
#endif
/* ARGSUSED */
static void
start1 (ARG_DUMMIES argc, argp)
DECL_DUMMIES
int argc;
char *argp;
{
char **argv = &argp;
/* The environment starts just after ARGV. */
__environ = &argv[argc + 1];
/* If the first thing after ARGV is the arguments
themselves, there is no environment. */
if ((char *) __environ == *argv)
/* The environment is empty. Make __environ
point at ARGV[ARGC], which is NULL. */
--__environ;
/* Do C library initializations. */
__libc_init (argc, argv, __environ);
/* Call the user program. */
exit (main (argc, argv, __environ));
}