NetBSD/lib/csu/hppa/crt0.c

159 lines
5.3 KiB
C

/* $NetBSD: crt0.c,v 1.4 2003/10/06 05:28:05 matt Exp $ */
/*
* Copyright (c) 2002 Matt Fredette
* Copyright (c) 1999 Klaus Klein
* Copyright (c) 1995 Christopher G. Demetriou
* 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 for the
* NetBSD Project. See http://www.NetBSD.org/ for
* information about NetBSD.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* 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.
*
* <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
*/
#include "common.h"
int __global __asm ("$global$") = 0;
static void ___start __P((struct ps_strings *,
void (*cleanup) __P((void)), const Obj_Entry *, int))
#ifdef __GNUC__
__attribute__((__unused__))
#endif
;
__asm("\n"
" .text \n"
" .align 4 \n"
" .globl _start \n"
" .globl _start \n"
" .type __start,@function \n"
" .type __start,@function \n"
"_start: \n"
"__start: \n"
" .import $global$, data \n"
" ldil L%$global$, %r27 \n"
" ldo R%$global$(%r27), %r27 \n"
" copy %r27, %r19 \n"
" b ___start \n"
" copy %r27, %arg3 \n");
static void
___start(ps_strings, cleanup, obj, dp)
struct ps_strings *ps_strings;
void (*cleanup) __P((void)); /* from shared loader */
const Obj_Entry *obj; /* from shared loader */
int dp;
{
int argc;
char **argv;
int fini_plabel[2];
argc = ps_strings->ps_nargvstr;
argv = ps_strings->ps_argvstr;
environ = ps_strings->ps_envstr;
if ((__progname = argv[0]) != NULL) { /* NULL ptr if argc = 0 */
if ((__progname = _strrchr(__progname, '/')) == NULL)
__progname = argv[0];
else
__progname++;
}
if (ps_strings != (struct ps_strings *)0)
__ps_strings = ps_strings;
#ifdef DYNAMIC
/*
* XXX fredette - when not compiling PIC, you currently
* can't detect an undefined weak symbol by seeing if
* its address is NULL. The compiler emits code to find
* _DYNAMIC relative to %dp, the assembler notes the
* needed relocations, but when the linker sees that the
* (weak) symbol isn't defined it drops the ball - the
* relocations are never filled, and the binary ends up
* with code that sees an address of %dp plus zero,
* which != NULL.
*
* Arguably the linker could/should distinguish between
* code that is after a weak undefined symbol's contents
* from code that is after its address. In the first case,
* it would warn and/or bail. In the second case, it
* would fix up instructions to give a symbol address
* of NULL.
*
* For now, we take the easy way out and compare &_DYNAMIC
* to %dp, as well as to NULL.
*/
if (&_DYNAMIC != NULL && (int)&_DYNAMIC != dp)
_rtld_setup(cleanup, obj);
#endif
#ifdef MCRT0
atexit(_mcleanup);
monstartup((u_long)&_eprol, (u_long)&_etext);
#endif
/*
* Since crt0.o, crtbegin.o, and crtend.o are always
* compiled PIC, they must have %r19 set correctly on
* entry to any function they contain. However, when
* a program is linked statically, the linker does
* not fill a PLABEL relocation with a pointer to a
* true PLABEL, it just fills it with the offset of the
* function. This shows the linker's assumption that
* when linking statically, *all* of the code has *not*
* been compiled PIC. I guess to assume otherwise
* would be a performance hit, as you would end up
* with unnecessary PLABELs for function pointers.
*
* But here, passing the address of the PIC _fini to
* atexit, we must make sure that we pass a PLABEL.
*/
fini_plabel[0] = (int)_fini;
if (fini_plabel[0] & 2)
/* _fini is already a PLABEL. */
atexit(_fini);
else {
fini_plabel[1] = dp;
atexit((void (*)(void))(((int)fini_plabel) | 2));
}
_init();
exit(main(argc, argv, environ));
}
/*
* NOTE: Leave the RCS ID _after_ __start(), in case it gets placed in .text.
*/
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: crt0.c,v 1.4 2003/10/06 05:28:05 matt Exp $");
#endif /* LIBC_SCCS and not lint */
#include "common.c"