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#!/usr/bin/env python
#-*- coding:utf-8 -*-
from sys import stdout
from string import printable
def xxx_isprint(jitter):
'''
#include <ctype.h>
int isprint(int c);
checks for any printable character including space.
'''
ret_addr, (c,) = jitter.func_args_stdcall(1)
ret = chr(c & 0xFF) in printable and 1 or 0
return jitter.func_ret_stdcall(ret_addr, ret)
def xxx_memcpy(jitter):
'''
#include <string.h>
void *memcpy(void *dest, const void *src, size_t n);
copies n bytes from memory area src to memory area dest.
'''
ret_addr, (dest, src, n) = jitter.func_args_stdcall(3)
jitter.vm.set_mem(dest, jitter.vm.get_mem(src, n))
return jitter.func_ret_stdcall(ret_addr, dest)
def xxx_puts(jitter):
'''
#include <stdio.h>
int puts(const char *s);
writes the string s and a trailing newline to stdout.
'''
ret_addr, (s,) = jitter.func_args_stdcall(1)
while True:
c = jitter.vm.get_mem(s, 1)
s += 1
if c == '\x00':
break
stdout.write(c)
stdout.write('\n')
return jitter.func_ret_stdcall(ret_addr, 1)
def xxx_snprintf(jitter):
'''
#include <stdio.h>
int snprintf(char *str, size_t size, const char *format, ...);
writes to string str according to format format and at most size bytes.
'''
ret_addr, (string, size, fmt) = jitter.func_args_stdcall(3)
curarg, output = 3, ''
while True:
c = jitter.vm.get_mem(fmt, 1)
fmt += 1
if c == '\x00':
break
if c == '%':
token = '%'
while True:
c = jitter.vm.get_mem(fmt, 1)
fmt += 1
token += c
if c in '%cdfsux':
break
c = token % jitter.get_arg_n_stdcall(curarg)
curarg += 1
output += c
output = output[:size - 1]
ret = len(output)
jitter.vm.set_mem(string, output + '\x00')
return jitter.func_ret_stdcall(ret_addr, ret)
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