Teach me to remove bloat!

Hey guys, I would like some pointer (no, not that kind) on removing bloat in code. Here is a fully functional piece of code that I wrote which I'm worried about bloat in. How do I shorten this?

int get_input()
{
    int count, paren_count, total_count, c;
    char *input, *temp;

    input = (char *) malloc (500 * sizeof (char));

    if (input == NULL) return 0;
    printf("%% ");
    for (count = paren_count = total_count = 0; (c = getchar()) != EOF; count++, input++, total_count++)
    {
        if (count == 499)
        {
            input -= total_count;
            temp = (char *) realloc (input, (500 + total_count) * sizeof (char));
            if (temp == NULL)
                return 0;
            input = temp;
            input += total_count;
        }
        if (c == '\n')
        {
            *input = '\0';
            temp = input;
            temp -= (count);
            count = 0;
            for (; *temp != '\0'; temp++)
            {
                if (*temp == '(')
                    paren_count++;
                else if (*temp == ')')
                    paren_count--;
            }
            if (paren_count == 0)
                break;
            printf("  ");
        }
        *input = c;
    }
    *temp = '\0';
    input -= total_count;
    printf("%s\n", input);
    free(input);
    return 0;
}

>>49
There's CL compilers which compile to C and some interpreters written in C, those should not be limited to CPU arch (that said, how many platforms do you intend to support? Most major ones have CL compilers working on them, but I guess not all of them. Maybe Scheme would be a simpler choice for this, however ECL should fit the bill too.)