/*
 * cutup: cut up a command line
 */
#include <stdio.h>
#include <ctype.h>
#include <malloc.h>
#include <string.h>		/* for definition of strdup() */
#include "args.h"

/*
 * newargs() initializes an arg_t structure
 * (c++ would do this with a arg_t class.  Finally a good reason to use
 * c++, and not a compiler in sight)
 */
newargs(args)
struct arg_t *args;
{
    args->argc = 0;
    args->argv = malloc(1);
} /* newargs */

/*
 * disposeargs() throws away an arg_t structure
 */
disposeargs(args)
struct arg_t *args;
{
    register i;

    for (i=args->argc; i-- > 0; )
	free(args->argv[i]);
    free(args->argv);
    args->argc = args->argv = 0;
} /* disposeargs */


/*
 * addarg() adds an argument to an arg_t structure.  using c++, you could
 * just overload + to do this :-(
 */
addarg(item, list)
char *item;
struct arg_t *list;
{
    if (list->argv = realloc(list->argv, (1+list->argc)*sizeof list->argv[0]))
	list->argv[list->argc++] = strdup(item);
    else {
	newargs(list);
	no_more_core();
    }
    return list->argc;
} /* addarg */


/*
 * isesc() is the given character one that needs to be escaped?
 */
isesc(c)
{
    switch (c) {
    case '"': case '\'': case '`': case '\\':
    case ';': case '|':  case '&': case '*':
    case ' ': case '\t': case '\n': case '?':
    case '<': case '>': case '=':
	return 1;
    }
    return 0;
}

cutup(text, args, io)
register char *text;
struct arg_t *args, *io;
{
    register char c;
    register i=0;
    register ioarg=0;
    char buf[512];

    newargs(args);
    newargs(io);

    while (c = *text++) {
	if (isspace(c)) {
	    if (i>0) {
		buf[i] = 0;
		i=0;
		addarg(buf, ioarg ? io : args);
		ioarg=0;
	    }
	}
	else if (c == '\\' && isesc(*text))
	    buf[i++] = *text++;
	else if (c == '"' || c == '\'' || c == '`') {
	    while (*text && *text != c) {
		if (*text == '\\' && isesc(text[1])) {
		    buf[i++] = *++text;
		    ++text;
		}
		else
		    buf[i++] = *text++;
	    }
	    if (*text) text++;
	}
	else {
	    if (c == '<' || c == '>')
		ioarg=1;
	    buf[i++] = c;
	}
    }
    if (i>0) {
	buf[i] = 0;
	i=0;
	addarg(buf, ioarg ? io : args);
    }
} /* cutup */