/* build a list from  a null-terminated char* vector. */
#include "cstuff.h"
s48_value char_pp_2_string_list(char **vec){
    char ** ptr = vec;
    s48_value list = S48_NULL;

    S48_DECLARE_GC_PROTECT(1);
    S48_GC_PROTECT_1(list);
    
    while (ptr && *(ptr)){
      list = s48_cons (s48_enter_string (*ptr), list);
      ptr++;
    }
    S48_GC_UNPROTECT();
    return list;
}

char *scheme2c_strcpy(s48_value sstr)
{
    char *result;
    int slen;

    slen = S48_STRING_LENGTH(sstr);
    result = Malloc(char, slen+1);

    if( result == NULL ) {
        fprintf(stderr,
                "Fatal error: C stub tried to copy Scheme string,\n"
                "but malloc failed on arg 0x%x, errno %d.\n",
                sstr, errno);
        exit(-1);
        }

    memcpy(result, s48_extract_string(sstr), slen);
    result[slen] = '\000';
    return result;
}

s48_value strlen_or_false(const char *s)
{ return s ?  s48_enter_fixnum(strlen(s)) : S48_FALSE; }

/* Helper function for arg checking. Why bother, actually? */
void cig_check_nargs(int arity, int nargs, const char *fn)
{
   if( arity != nargs ) {
       fprintf(stderr,
	       "Cig fatal error (%s) -- C stub expected %d arg%s, "
	       "but got %d.\n",
	       fn, arity, (arity == 1) ? "" : "s", nargs);
       exit(-1);
   }
}