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#include <stdio.h>
/**
* On reproduit un code similaire à celui d'un fichier de Busybox (busybox-1.30.0/libbb/appletlib.c).
*
* La commande de compilation est :
*
* arm-linux-gnueabi-gcc -Wp,-MD,libbb/.appletlib.o.d -std=gnu99 -Iinclude -Ilibbb -include include/autoconf.h -D_GNU_SOURCE -DNDEBUG -D"BB_VER=KBUILD_STR(1.30.0)" -Wall -Wshadow -Wwrite-strings -Wundef -Wstrict-prototypes -Wunused -Wunused-parameter -Wunused-function -Wunused-value -Wmissing-prototypes -Wmissing-declarations -Wno-format-security -Wdeclaration-after-statement -Wold-style-definition -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 -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(appletlib)" -D"KBUILD_MODNAME=KBUILD_STR(appletlib)" -c -o libbb/appletlib.o libbb/appletlib.c
*
*/
/*
unsigned FAST_FUNC string_array_len(char **argv)
{
char **start = argv;
while (*argv)
argv++;
return argv - start;
}
*/
unsigned __attribute__ ((naked)) string_array_len(char **argv)
{
/*
0x00009a0c <+0>: mov r2, r0
0x00009a10 <+4>: mov r3, r2
0x00009a14 <+8>: ldr r1, [r3]
0x00009a18 <+12>: add r2, r2, #4
0x00009a1c <+16>: cmp r1, #0
0x00009a20 <+20>: bne 0x9a10 <string_array_len+4>
0x00009a24 <+24>: rsb r0, r0, r3
0x00009a28 <+28>: asr r0, r0, #2
0x00009a2c <+32>: bx lr
*/
asm (
"mov r2, r0" "\n"
".Lbl_9a10%=:" "\n"
"mov r3, r2" "\n"
"ldr r1, [r3]" "\n"
"add r2, r2, #4" "\n"
"cmp r1, #0" "\n"
"bne .Lbl_9a10%=" "\n"
"rsb r0, r0, r3" "\n"
"asr r0, r0, #2" "\n"
"bx lr" "\n"
::"r" (argv));
}
int main(int argc, char **argv)
{
return string_array_len(argv);
}
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