/*
* TKCreate creates a new TokenizerT object for a given set of serarator
* characters (given as a string) and a tken stream (given as a string).
*
* TKCreate should copy the two arguments so that it is not dependant on them
* staying immutable after returning.
*
* If the function succeeds, it returns a non-NULL TokenizerT.
* Else it returns NULL.
*
*/
TokenizerT *TKCreate ( char const *const seperators, char const *const ts ) {
/*
* Make copies of the two strings.
* This uses malloc so it is creating dynamically allocated strings.
*/
char *const delimiters = simplify_string( seperators );
char *const token = simplify_string( ts );
TokenizerT *const tk = malloc( sizeof( TokenizerT ) );
/* If neither string is NULL create a TokenizerT and return a pointer. */
if ( delimiters && token && tk ) {
*tk = (TokenizerT) {delimiters, token, token};
return tk;
}
/* Else return NULL. */
return NULL;
}
char *look_in_lisp_variable(char *o, int prefix)
{
Lisp_Object nil, var;
/*
* I will start by tagging a '$' (or whatever) on in front of the
* parameter name.
*/
o[0] = (char)prefix;
var = make_undefined_symbol(o);
nil = C_nil;
/*
* make_undefined_symbol() could fail either if we had utterly run out
* of memory or if somebody generated an interrupt (eg ^C) around now. Ugh.
*/
if (exception_pending())
{ flip_exception();
return NULL;
}
/*
* If the variable $name was undefined then I use an empty replacement
* text for it. Otherwise I need to look harder at its value.
*/
if (qvalue(var) == unset_var) return o;
else
{ Header h;
intptr_t len;
var = qvalue(var);
/*
* Mostly I expect that the value will be a string or symbol.
*/
#ifdef COMMON
if (complex_stringp(var))
{ var = simplify_string(var);
nil = C_nil;
if (exception_pending())
{ flip_exception();
return NULL;
}
}
#endif /* COMMON */
if (symbolp(var))
{ var = get_pname(var);
nil = C_nil;
if (exception_pending())
{ flip_exception();
return NULL;
}
h = vechdr(var);
}
else if (!is_vector(var) ||
type_of_header(h = vechdr(var)) != TYPE_STRING)
return NULL;
len = length_of_header(h) - CELL;
/*
* Copy the characters from the string or from the name of the variable
* into the file-name buffer. There could at present be a crash here
* if the expansion was very very long and overflowed my buffer. Tough
* luck for now - people doing that (maybe) get what they (maybe) deserve.
*/
memcpy(o, (char *)var + (CELL - TAG_VECTOR), (size_t)len);
o = o + len;
return o;
}
}
