#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int get_init_addr (char *exe) {
	FILE *fp;
	unsigned char str[5];
	int i;
	fp = fopen (exe, "rb");
	if (fp==NULL)
		return 0;
	for (i=0;i<=0x5f;i++)
		fgetc (fp);
	fgets (str,sizeof(str),fp);
	fclose(fp);
	return (str[3]*(1<<24)+str[2]*(1<<16)+str[1]*(1<<8)+str[0]); 
}

int replace_bytes (char *exe, int repl_addr, int *bytes, int len) {
	FILE *fp;
	unsigned char ch,*ed;
	int i,addr,d,size;
	addr = get_init_addr (exe);
	fp=fopen (exe, "rb");
	if (fp==NULL || !addr)
		return 0;
	ed=malloc(1);
	for (i=0;!feof (fp);) {
		ed=realloc (ed,++i);
		ed[i-1]=fgetc(fp);
	}
	size=--i;
	fclose (fp);
	for (i=addr&0x00000FFF;addr<repl_addr;i++,addr++);
	for (d=0;d<len;d++,i++)
		ed[i]=bytes[d];
	fp=fopen (exe,"wb");
	if (fp==NULL)
		return  0;
	for (i=0;i<size;i++)
		fputc (ed[i],fp);
	fclose (fp);
	return 1;
}

int str2addr (char *exe, char *str) {
	int addr,i,size;
	unsigned char *ed;
	addr=get_init_addr (exe);
	FILE *fp;
	fp=fopen (exe, "rb");
	ed=malloc(1);
	for (i=0;!feof (fp);) {
		ed=realloc (ed,++i);
		ed[i-1]=fgetc(fp);
	}
	size=--i;
	fclose (fp);
	for (i=addr&0x00000FFF;i<size;i++,addr++) 
		if (!strncmp (ed+i,str,strlen(str)))
			break;
	return addr;
	return 0;
}

char *addr2str (char *exe, int saddr) {
	int addr,i,size;
	unsigned char *ed,*str;
	addr=get_init_addr (exe);
	FILE *fp;
	fp=fopen (exe, "rb");
	ed=malloc(1);
	for (i=0;!feof (fp);) {
		ed=realloc (ed,++i);
		ed[i-1]=fgetc(fp);
	}
	size=--i;
	fclose (fp);
	for (i=addr&0x00000FFF;addr<saddr;addr++,i++);
	str=malloc (strlen(ed+i)+1);
	strcpy (str,ed+i);
	return str;
}

int replace_func (char *exe, int addr, int faddr) {
	unsigned int to_sub;
	int arr [5];
	to_sub=faddr-(addr+5);
	arr[0]=0xe8;
	arr[1]=to_sub & 0x000000FF;
	arr[2]=(to_sub & 0x0000FF00)>>8;
	arr[3]=(to_sub & 0x00FF0000)>>16;
	arr[4]=(to_sub & 0xFF000000)>>24;
	return replace_bytes (exe,addr,arr,5);
}