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// libc-free platform layer for x86-32 Linux
// This is free and unencumbered software released into the public domain.
#include "u-config.c"
#define SYS_close 6
#define SYS_exit 1
#define SYS_mmap 192 // actually mmap2
#define SYS_open 5
#define SYS_read 3
#define SYS_write 4
#include "linux_noarch.c"
asm (
" .globl _start\n"
"_start: mov %esp, %eax\n"
" sub $12, %esp\n"
" push %eax\n"
" call entrypoint\n"
);
static long syscall1(long n, long a)
{
long r;
asm volatile (
"int $0x80"
: "=a"(r)
: "a"(n), "b"(a)
: "memory"
);
return r;
}
static long syscall2(long n, long a, long b)
{
long r;
asm volatile (
"int $0x80"
: "=a"(r)
: "a"(n), "b"(a), "c"(b)
);
return r;
}
static long syscall3(long n, long a, long b, long c)
{
long r;
asm volatile (
"int $0x80"
: "=a"(r)
: "a"(n), "b"(a), "c"(b), "d"(c)
: "memory"
);
return r;
}
static long syscall6(long n, long a, long b, long c, long d, long e, long f)
{
long r;
asm volatile (
"push %7\n"
"push %%ebp\n"
"mov 4(%%esp), %%ebp\n"
"int $0x80\n"
"pop %%ebp\n"
"add $4, %%esp\n"
: "=a"(r)
: "a"(n), "b"(a), "c"(b), "d"(c), "S"(d), "D"(e), "m"(f)
: "memory"
);
return r;
}
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