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YukiSakamoto/construct.c

Created September 2, 2012 15:10
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gcc extension-sample(constructor & destructor)
Raw
construct.c
#include <stdio.h>
__attribute__((constructor))
int pre_main(void)
{
printf("%s\n", __func__);
getchar();
return 0;
}
__attribute__((destructor))
int after_main(void)
{
printf("%s\n", __func__);
return 0;
}
int main(void)
{
printf("%s\n", __func__);
return 0;
}
Raw
construct.s
.section __TEXT,__text,regular,pure_instructions
.globl _pre_main
.align 4, 0x90
_pre_main:
pushl %ebp
movl %esp, %ebp
subl $24, %esp
call L1$pb
L1$pb:
popl %eax
leal ___func__.1863-L1$pb(%eax), %eax
movl %eax, (%esp)
call _puts
call _getchar
movl $0, -8(%ebp)
movl -8(%ebp), %eax
movl %eax, -4(%ebp)
movl -4(%ebp), %eax
addl $24, %esp
popl %ebp
ret
.globl _after_main
.align 4, 0x90
_after_main:
pushl %ebp
movl %esp, %ebp
subl $24, %esp
call L2$pb
L2$pb:
popl %eax
leal ___func__.1869-L2$pb(%eax), %eax
movl %eax, (%esp)
call _puts
movl $0, -8(%ebp)
movl -8(%ebp), %eax
movl %eax, -4(%ebp)
movl -4(%ebp), %eax
addl $24, %esp
popl %ebp
ret
.globl _main
.align 4, 0x90
_main:
pushl %ebp
movl %esp, %ebp
subl $24, %esp
call L3$pb
L3$pb:
popl %eax
leal ___func__.1875-L3$pb(%eax), %eax
movl %eax, (%esp)
call _puts
movl $0, -8(%ebp)
movl -8(%ebp), %eax
movl %eax, -4(%ebp)
movl -4(%ebp), %eax
addl $24, %esp
popl %ebp
ret
.section __TEXT,__cstring,cstring_literals
.align 2
___func__.1863:
.asciz "pre_main"
.align 2
___func__.1869:
.asciz "after_main"
.align 2
___func__.1875:
.asciz "main"
.section __DATA,__mod_init_func,mod_init_funcs
.align 2
.long _pre_main
.section __DATA,__mod_term_func,mod_term_funcs
.align 2
.long _after_main
.subsections_via_symbols
Raw
disasemble
construct: ファイル形式 mach-o-i386
セクション .text の逆アセンブル:
00001e70 <start>:
1e70: 6a 00 push $0x0
1e72: 89 e5 mov %esp,%ebp
1e74: 83 e4 f0 and $0xfffffff0,%esp
1e77: 83 ec 10 sub $0x10,%esp
1e7a: 8b 5d 04 mov 0x4(%ebp),%ebx
1e7d: 89 1c 24 mov %ebx,(%esp)
1e80: 8d 4d 08 lea 0x8(%ebp),%ecx
1e83: 89 4c 24 04 mov %ecx,0x4(%esp)
1e87: 83 c3 01 add $0x1,%ebx
1e8a: c1 e3 02 shl $0x2,%ebx
1e8d: 01 cb add %ecx,%ebx
1e8f: 89 5c 24 08 mov %ebx,0x8(%esp)
1e93: 8b 03 mov (%ebx),%eax
1e95: 83 c3 04 add $0x4,%ebx
1e98: 85 c0 test %eax,%eax
1e9a: 75 f7 jne 1e93 <start+0x23>
1e9c: 89 5c 24 0c mov %ebx,0xc(%esp)
1ea0: e8 7b 00 00 00 call 1f20 <_main>
1ea5: 89 04 24 mov %eax,(%esp)
1ea8: e8 a3 00 00 00 call 1f50 <_exit$stub>
1ead: f4 hlt
1eae: 90 nop
1eaf: 90 nop
00001eb0 <_pre_main>:
1eb0: 55 push %ebp
1eb1: 89 e5 mov %esp,%ebp
1eb3: 83 ec 18 sub $0x18,%esp
1eb6: e8 00 00 00 00 call 1ebb <_pre_main+0xb>
1ebb: 58 pop %eax
1ebc: 8d 80 d5 00 00 00 lea 0xd5(%eax),%eax
1ec2: 89 04 24 mov %eax,(%esp)
1ec5: e8 92 00 00 00 call 1f5c <_puts$stub>
1eca: e8 87 00 00 00 call 1f56 <_getchar$stub>
1ecf: c7 45 f8 00 00 00 00 movl $0x0,-0x8(%ebp)
1ed6: 8b 45 f8 mov -0x8(%ebp),%eax
1ed9: 89 45 fc mov %eax,-0x4(%ebp)
1edc: 8b 45 fc mov -0x4(%ebp),%eax
1edf: 83 c4 18 add $0x18,%esp
1ee2: 5d pop %ebp
1ee3: c3 ret
1ee4: 66 0f 1f 44 00 00 nopw 0x0(%eax,%eax,1)
1eea: 66 0f 1f 44 00 00 nopw 0x0(%eax,%eax,1)
00001ef0 <_after_main>:
1ef0: 55 push %ebp
1ef1: 89 e5 mov %esp,%ebp
1ef3: 83 ec 18 sub $0x18,%esp
1ef6: e8 00 00 00 00 call 1efb <_after_main+0xb>
1efb: 58 pop %eax
1efc: 8d 80 a1 00 00 00 lea 0xa1(%eax),%eax
1f02: 89 04 24 mov %eax,(%esp)
1f05: e8 52 00 00 00 call 1f5c <_puts$stub>
1f0a: c7 45 f8 00 00 00 00 movl $0x0,-0x8(%ebp)
1f11: 8b 45 f8 mov -0x8(%ebp),%eax
1f14: 89 45 fc mov %eax,-0x4(%ebp)
1f17: 8b 45 fc mov -0x4(%ebp),%eax
1f1a: 83 c4 18 add $0x18,%esp
1f1d: 5d pop %ebp
1f1e: c3 ret
1f1f: 90 nop
00001f20 <_main>:
1f20: 55 push %ebp
1f21: 89 e5 mov %esp,%ebp
1f23: 83 ec 18 sub $0x18,%esp
1f26: e8 00 00 00 00 call 1f2b <_main+0xb>
1f2b: 58 pop %eax
1f2c: 8d 80 7d 00 00 00 lea 0x7d(%eax),%eax
1f32: 89 04 24 mov %eax,(%esp)
1f35: e8 22 00 00 00 call 1f5c <_puts$stub>
1f3a: c7 45 f8 00 00 00 00 movl $0x0,-0x8(%ebp)
1f41: 8b 45 f8 mov -0x8(%ebp),%eax
1f44: 89 45 fc mov %eax,-0x4(%ebp)
1f47: 8b 45 fc mov -0x4(%ebp),%eax
1f4a: 83 c4 18 add $0x18,%esp
1f4d: 5d pop %ebp
1f4e: c3 ret
セクション __TEXT.__symbol_stub の逆アセンブル:
00001f50 <_exit$stub>:
1f50: ff 25 1c 20 00 00 jmp *0x201c
00001f56 <_getchar$stub>:
1f56: ff 25 20 20 00 00 jmp *0x2020
00001f5c <_puts$stub>:
1f5c: ff 25 24 20 00 00 jmp *0x2024
セクション __TEXT.__stub_helper の逆アセンブル:
00001f64 <__TEXT.__stub_helper>:
1f64: 68 00 00 00 00 push $0x0
1f69: e9 16 00 00 00 jmp 1f84 <_puts$stub+0x28>
1f6e: 68 0c 00 00 00 push $0xc
1f73: e9 0c 00 00 00 jmp 1f84 <_puts$stub+0x28>
1f78: 68 1b 00 00 00 push $0x1b
1f7d: e9 02 00 00 00 jmp 1f84 <_puts$stub+0x28>
1f82: 00 00 add %al,(%eax)
1f84: 68 18 20 00 00 push $0x2018
1f89: ff 25 14 20 00 00 jmp *0x2014
1f8f: 90 nop
セクション __TEXT.__unwind_info の逆アセンブル:
00001fad <__TEXT.__unwind_info>:
1fad: 01 00 add %eax,(%eax)
1faf: 00 00 add %al,(%eax)
1fb1: 1c 00 sbb $0x0,%al
1fb3: 00 00 add %al,(%eax)
1fb5: 00 00 add %al,(%eax)
1fb7: 00 00 add %al,(%eax)
1fb9: 1c 00 sbb $0x0,%al
1fbb: 00 00 add %al,(%eax)
1fbd: 00 00 add %al,(%eax)
1fbf: 00 00 add %al,(%eax)
1fc1: 1c 00 sbb $0x0,%al
1fc3: 00 00 add %al,(%eax)
1fc5: 02 00 add (%eax),%al
1fc7: 00 00 add %al,(%eax)
1fc9: 70 0e jo 1fd9 <___func__.1875+0x31>
1fcb: 00 00 add %al,(%eax)
1fcd: 34 00 xor $0x0,%al
1fcf: 00 00 add %al,(%eax)
1fd1: 34 00 xor $0x0,%al
1fd3: 00 00 add %al,(%eax)
1fd5: 50 push %eax
1fd6: 0f 00 00 sldt (%eax)
1fd9: 00 00 add %al,(%eax)
1fdb: 00 00 add %al,(%eax)
1fdd: 34 00 xor $0x0,%al
1fdf: 00 00 add %al,(%eax)
1fe1: 03 00 add (%eax),%eax
1fe3: 00 00 add %al,(%eax)
1fe5: 0c 00 or $0x0,%al
1fe7: 01 00 add %eax,(%eax)
1fe9: 10 00 adc %al,(%eax)
1feb: 01 00 add %eax,(%eax)
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