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#include <stdio.h>
/**
* On reproduit un code similaire à celui d'un fichier de Busybox (busybox-1.30.0/libbb/libbb/endofname.c).
*
* La commande de compilation est :
*
* arm-linux-gnueabi-gcc -I../include -I../libbb -include ../include/autoconf.h -D_GNU_SOURCE -DNDEBUG -fno-builtin-strlen -finline-limit=0 -fomit-frame-pointer -ffunction-sections -fdata-sections -fno-guess-branch-probability -funsigned-char -static-libgcc -falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1 -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-builtin-printf -Os -E -c -o a.out endofname.c
*
*/
/*
static __attribute__ ((always_inline)) __inline__ int bb_ascii_isalnum(unsigned char a)
{
unsigned char b = a - '0';
if (b <= 9)
return (b <= 9);
b = (a|0x20) - 'a';
return b <= 'z' - 'a';
}
const char *endofname(const char *name)
{
if (!((*name) == '_' || ((unsigned char)((((unsigned char)(*name))|0x20) - 'a') <= ('z' - 'a'))))
return name;
while (*++name) {
if (!((*name) == '_' || bb_ascii_isalnum((unsigned char)(*name))))
break;
}
return name;
}
*/
void __attribute__ ((naked)) endofname(const char *name)
{
/*
83bc: e5d03000 ldrb r3, [r0]
83c0: e353005f cmp r3, #95 ; 0x5f
83c4: 0a000003 beq 83d8 <endofname+0x1c>
83c8: e3833020 orr r3, r3, #32
83cc: e2433061 sub r3, r3, #97 ; 0x61
83d0: e3530019 cmp r3, #25
83d4: 812fff1e bxhi lr
83d8: e5f03001 ldrb r3, [r0, #1]!
83dc: e3530000 cmp r3, #0
83e0: 0a000005 beq 83fc <endofname+0x40>
83e4: e353005f cmp r3, #95 ; 0x5f
83e8: 0afffffa beq 83d8 <endofname+0x1c>
83ec: e2432030 sub r2, r3, #48 ; 0x30
83f0: e3520009 cmp r2, #9
83f4: 9afffff7 bls 83d8 <endofname+0x1c>
83f8: eafffff2 b 83c8 <endofname+0xc>
83fc: e12fff1e bx lr
*/
asm (
"ldrb r3, [r0]" "\n"
"cmp r3, #95" "\n"
"beq .Lbl_83d8%=" "\n"
".Lbl_83c8%=:" "\n"
"orr r3, r3, #32" "\n"
"sub r3, r3, #97" "\n"
"cmp r3, #25" "\n"
"bxhi lr" "\n"
".Lbl_83d8%=:" "\n"
"ldrb r3, [r0, #1]!" "\n"
"cmp r3, #0" "\n"
"beq .Lbl_83fc%=" "\n"
"cmp r3, #95" "\n"
"beq .Lbl_83d8%=" "\n"
"sub r2, r3, #48" "\n"
"cmp r2, #9" "\n"
"bls .Lbl_83d8%=" "\n"
"b .Lbl_83c8%=" "\n"
".Lbl_83fc%=:" "\n"
"bx lr" "\n"
::"r" (name));
}
int main(int argc, char **argv)
{
endofname(argv[0]);
return 0;
}
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