A quick-and-dirty tongue-in-cheek generator of a tiny assembler source code written in assembler ;)

asm.c

//make asm ; python -c "open('asm.S','w').write('\n'.join(map(lambda x: 'db 0x%02x' % ord(x) ,open('asm','r').read())))"

#include "stdlib.h"
#include "assert.h"
#include "stdio.h"

int hex2int(char hex)
{
    if(hex<'0'|| (hex<'A' && (hex>'Z' && hex<'a')) || hex>'z' )
    {
            fprintf(stderr,"FATAL: Invalid syntax: expected "
                    "\"db 0x??\", no multiple whitespace allowed.\n");
            exit(1);
    }
    if(tolower(hex)=='a') return 10;
    if(tolower(hex)=='b') return 11;
    if(tolower(hex)=='c') return 12;
    if(tolower(hex)=='d') return 13;
    if(tolower(hex)=='e') return 14;
    if(tolower(hex)=='f') return 15;
    else
        return hex-48;
}

int main()
{
    int zero;
    char* line;
    char dec;
    do
    {
        zero = 0;
        line = NULL;
        getline(&line,&zero,stdin);
        if(feof(stdin)) break;
        if(!(tolower(line[0])=='d' && 
                    tolower(line[1])=='b' && 
                    line[2]==' ' && 
                    line[3]=='0' && 
                    line[4]=='x' && 
                    line[7]=='\n')
                )
        {
            fprintf(stderr,"FATAL: Invalid syntax: expected "
                    "\"db 0x??\", no multiple whitespace allowed.\n");
            return 1;
        }
        dec = hex2int(line[6])+hex2int(line[5])*16;
        printf("%c",dec);
        fflush(stdout);
        free(line);
    }
    while(!feof(stdin));
    return 0;
}