[unix-history] / gnu / usr.bin / ld / i386 / mdprologue.S

/*
 * Copyright (c) 1993 Paul Kranenburg
 * 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 Paul Kranenburg.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software withough 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: mdprologue.S,v 1.1 1993/10/16 21:53:16 pk Exp $
 */

/*
 * i386 run-time link editor entry points.
 */

#include <sys/syscall.h>
#define LCALL(x,y)	.byte 0x9a ; .long y; .word x

	.text
	.globl	_binder, _binder_entry

/*
 *	_rtl(int version, struct crt_ldso *crtp)
 */
#define FRAME	12			/* Size of stack frame */


_rtl:					# crt0 calls us here
	pushl	%ebp			# Allocate stack frame
	movl	%esp, %ebp
	subl	$FRAME, %esp
	pushl	%ebx
	call	1f			# PIC function prologue
1:
	popl	%ebx
	addl	$_GLOBAL_OFFSET_TABLE_+[.-1b], %ebx

	movl	12(%ebp), %eax		# Extract data from interface structure
	movl	(%eax),%eax		# base address of ld.so (first field)
					# setup arguments for rtld()
	movl	(%ebx), %ecx		# 1st entry in GOT is our __DYNAMIC
	addl	%eax, %ecx		#   add load address
	pushl	%ecx			# 3rd arg
	pushl	12(%ebp)		# 2nd arg == &crt.
	pushl	8(%ebp)			# 1st arg == version
	addl	_rtld@GOT(%ebx), %eax	# relocate address of function
	call	%eax			# _rtld(version, crtp, DYNAMIC)
	addl	$12,%esp		# pop arguments

	movl	(-FRAME-4)(%ebp), %ebx	# restore %ebx
	leave				# remove stack frame,
	ret				# let's rock

 # First call to a procedure generally comes through here for
 # binding.

_binder_entry:
	pushl	%ebp			# setup a stack frame
	movl	%esp, %ebp
	pusha				# save all regs

	movl	$0, %eax		# clear
	movl	4(%ebp), %esi		# return address in PLT
	movw	(%esi), %ax		# get hold of relocation number
	subl	$6, %esi		# make it point to the jmpslot

	pushl	%eax			# pushd arguments
	pushl	%esi			#
	call	_binder@PLT		# _binder(rpc, index)
	addl	$8, %esp		# pop arguments
	movl	%eax, 4(%ebp)		# return value from _binder() == actual
					#  address of function
	popa				# restore regs
	leave				# remove our stack frame
	ret

 # Special system call stubs which return real and effective user and group
 # id's.  Saves overhead of making separate calls for each.
 # !! Relies on compatability option in BSD 4.three-and-a-half

	.globl	_getreuid, _getregid
_getreuid:
	lea	SYS_getuid, %eax
	LCALL(7,0)
	jc	out
	movl	4(%esp), %ecx		# get 1st arg
	movl	%eax, (%ecx)		# put value in it
	movl	8(%esp), %ecx		# same for 2nd arg
	movl	%edx, (%ecx)		#
	ret				# done

_getregid:
	lea	SYS_getgid, %eax
	LCALL(7,0)
	jc	out
	movl	4(%esp), %ecx		# get 1st arg
	movl	%eax, (%ecx)		# put value in it
	movl	8(%esp), %ecx		# same for 2nd arg
	movl	%edx, (%ecx)		#
	ret				# done

out:	jmp	cerror@PLT		# Call common error routine
Commit	Line	Data
1136f72d PR	1	/*
	2	* Copyright (c) 1993 Paul Kranenburg
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by Paul Kranenburg.
	16	* 4. The name of the author may not be used to endorse or promote products
	17	* derived from this software withough specific prior written permission
	18	*
	19	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	20	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	21	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	22	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	23	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	24	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	25	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	26	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	27	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	28	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	29	*
	30	* $Id: mdprologue.S,v 1.1 1993/10/16 21:53:16 pk Exp $
	31	*/
	32
	33	/*
	34	* i386 run-time link editor entry points.
	35	*/
	36
	37	#include <sys/syscall.h>
	38	#define LCALL(x,y) .byte 0x9a ; .long y; .word x
	39
	40	.text
	41	.globl _binder, _binder_entry
	42
	43	/*
	44	* _rtl(int version, struct crt_ldso *crtp)
	45	*/
	46	#define FRAME 12 /* Size of stack frame */
	47
	48
	49	_rtl: # crt0 calls us here
	50	pushl %ebp # Allocate stack frame
	51	movl %esp, %ebp
	52	subl $FRAME, %esp
	53	pushl %ebx
	54	call 1f # PIC function prologue
	55	1:
	56	popl %ebx
	57	addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ebx
	58
	59	movl 12(%ebp), %eax # Extract data from interface structure
	60	movl (%eax),%eax # base address of ld.so (first field)
	61	# setup arguments for rtld()
	62	movl (%ebx), %ecx # 1st entry in GOT is our __DYNAMIC
	63	addl %eax, %ecx # add load address
	64	pushl %ecx # 3rd arg
65	pushl 12(%ebp) # 2nd arg == &crt.
66	pushl 8(%ebp) # 1st arg == version
67	addl _rtld@GOT(%ebx), %eax # relocate address of function
68	call %eax # _rtld(version, crtp, DYNAMIC)
69	addl $12,%esp # pop arguments
70
71	movl (-FRAME-4)(%ebp), %ebx # restore %ebx
72	leave # remove stack frame,
73	ret # let's rock
74
75	# First call to a procedure generally comes through here for
76	# binding.
77
78	_binder_entry:
79	pushl %ebp # setup a stack frame
80	movl %esp, %ebp
81	pusha # save all regs
82
83	movl $0, %eax # clear
84	movl 4(%ebp), %esi # return address in PLT
85	movw (%esi), %ax # get hold of relocation number
86	subl $6, %esi # make it point to the jmpslot
87
88	pushl %eax # pushd arguments
89	pushl %esi #
90	call _binder@PLT # _binder(rpc, index)
91	addl $8, %esp # pop arguments
92	movl %eax, 4(%ebp) # return value from _binder() == actual
93	# address of function
94	popa # restore regs
95	leave # remove our stack frame
96	ret
97
98	# Special system call stubs which return real and effective user and group
99	# id's. Saves overhead of making separate calls for each.
100	# !! Relies on compatability option in BSD 4.three-and-a-half
101
102	.globl _getreuid, _getregid
103	_getreuid:
104	lea SYS_getuid, %eax
105	LCALL(7,0)
106	jc out
107	movl 4(%esp), %ecx # get 1st arg
108	movl %eax, (%ecx) # put value in it
109	movl 8(%esp), %ecx # same for 2nd arg
110	movl %edx, (%ecx) #
111	ret # done
112
113	_getregid:
114	lea SYS_getgid, %eax
115	LCALL(7,0)
116	jc out
117	movl 4(%esp), %ecx # get 1st arg
118	movl %eax, (%ecx) # put value in it
119	movl 8(%esp), %ecx # same for 2nd arg
120	movl %edx, (%ecx) #
121	ret # done
122
123	out: jmp cerror@PLT # Call common error routine
124