/*
 * routines for node management
 *
 * Copyright (C) 1988 Free Software Foundation
 *
 */

/*
 * GAWK is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY.  No author or distributor accepts responsibility to anyone for
 * the consequences of using it or for whether it serves any particular
 * purpose or works at all, unless he says so in writing. Refer to the GAWK
 * General Public License for full details. 
 *
 * Everyone is granted permission to copy, modify and redistribute GAWK, but
 * only under the conditions described in the GAWK General Public License.  A
 * copy of this license is supposed to have been given to you along with GAWK
 * so you can know your rights and responsibilities.  It should be in a file
 * named COPYING.  Among other things, the copyright notice and this notice
 * must be preserved on all copies. 
 *
 * In other words, go ahead and share GAWK, but don't try to stop anyone else
 * from sharing it farther.  Help stamp out software hoarding! 
 */

#include "awk.h"

AWKNUM
r_force_number(n)
NODE *n;
{
	double atof();

#ifdef DEBUG
	if (n == NULL)
		cant_happen();
	if (n->type != Node_val)
		cant_happen();
	if(n->flags == 0)
		cant_happen();
	if (n->flags & NUM)
		return n->numbr;
#endif
	n->numbr = (AWKNUM) atof(n->stptr);
	n->flags |= NUM;
	return n->numbr;
}

NODE *
r_force_string(s)
NODE *s;
{
	char buf[30];
	char *fmt;

#ifdef DEBUG
	if (s == NULL)
		cant_happen();
	if (s->type != Node_val)
		cant_happen();
	if (s->flags & STR)
		return s;
	if (!(s->flags & NUM))
		cant_happen();
	if (s->stref != 0)
		cant_happen();
#endif
	s->flags |= STR;
	fmt = OFMT_node->var_value->stptr;
	/* integral value */
	if (STREQ(fmt, "%.6g") && (long) s->numbr == s->numbr)
		fmt = "%.11g";
	/* should check validity of user supplied OFMT */
	(void) sprintf(buf, fmt, s->numbr);
	s->stlen = strlen(buf);
	s->stref = 1;
	emalloc(s->stptr, char *, s->stlen + 1, "force_string");
	memcpy(s->stptr, buf, s->stlen+1);
	return s;
}

/*
 * This allocates a new node of type ty.  Note that this node will not go
 * away unless freed.
 */
NODE *
newnode(ty)
NODETYPE ty;
{
	register NODE *r;

	emalloc(r, NODE *, sizeof(NODE), "newnode");
	r->type = ty;
	r->flags = MALLOC;
	return r;
}

/*
 * Duplicate a node.  (For global strings, "duplicate" means crank up the
 * reference count.)  This creates global nodes. . . 
 */
NODE *
dupnode(n)
NODE *n;
{
	register NODE *r;

	if (n->flags & TEMP) {
		n->flags &= ~TEMP;
		n->flags |= MALLOC;
		return n;
	}
	if ((n->flags & (MALLOC|STR)) == (MALLOC|STR)) {
		if (n->stref < 255)
			n->stref++;
		return n;
	}
	emalloc(r, NODE *, sizeof(NODE), "dupnode");
	*r = *n;
	r->flags &= ~(PERM|TEMP);
	r->flags |= MALLOC;
	if (n->type == Node_val && (n->flags & STR)) {
		r->stref = 1;
		emalloc(r->stptr, char *, r->stlen + 1, "dupnode");
		bcopy(n->stptr, r->stptr, r->stlen);
		r->stptr[r->stlen] = '\0';
	}
	return r;
}

/* this allocates a node with defined numbr */
/* This creates global nodes! */
NODE *
make_number(x)
AWKNUM x;
{
	register NODE *r;

	r = newnode(Node_val);
	r->numbr = x;
	r->flags |= NUM;
	r->stref = 0;
	return r;
}

/*
 * This creates temporary nodes.  They go away quite quicly, so don't use
 * them for anything important 
 */
NODE *
tmp_number(x)
AWKNUM x;
{
	NODE *r;

	r = make_number(x);
	r->flags |= TEMP;
	return r;
}

/*
 * Make a string node.  If len==-1, the string passed in S is supposed to end
 * with a double quote, but have had the beginning double quote already
 * stripped off by yylex. If LEN!=-1, we don't care what s ends with.  This
 * creates a global node 
 */

NODE *
make_string(s, len)
char *s;
{
	register NODE *r;
	register char *pf, *pt;
	register int c;
	int count;

	/*
	 * the aborts are impossible because yylex is supposed to have
	 * already checked for unterminated strings 
	 */
	if (len == -1) {	/* Called from yyparse, find our own len */
		for (pf = pt = s; *pf != '\0' && *pf != '\"';) {
			c = *pf++;
			switch (c) {
			case '\0':
				cant_happen();

			case '\\':
				if (*pf == '\0')
					cant_happen();
				c = *pf++;
				switch (c) {
				case '\\':	/* no massagary needed */
				case '\'':
				case '\"':
					break;
				case '0':
				case '1':
				case '2':
				case '3':
				case '4':
				case '5':
				case '6':
				case '7':
#ifdef notdef
				case '8':
				case '9':
#endif
					c -= '0';
					count = 1;
					while (*pf && *pf >= '0' && *pf <= '7') {
						c = c * 8 + *pf++ - '0';
						if (++count >= 3)
							break;
					}
					break;
				case 'b':
					c = '\b';
					break;
				case 'f':
					c = '\f';
					break;
				case 'n':
					c = '\n';
					break;
				case 'r':
					c = '\r';
					break;
				case 't':
					c = '\t';
					break;
				case 'v':
					c = '\v';
					break;
				default:
					*pt++ = '\\';
					break;
				}
				/* FALL THROUGH */
			default:
				*pt++ = c;
				break;
			}
		}
		if (*pf == '\0')
			cant_happen();	/* hit the end of the buf */
		len = pt - s;
	}
	r = newnode(Node_val);
	emalloc(r->stptr, char *, len + 1, "make_string");
	r->stlen = len;
	r->stref = 1;
	bcopy(s, r->stptr, len);
	r->stptr[len] = '\0';	/* a hack */
	r->flags = (STR|MALLOC);

	return r;
}

/* This should be a macro for speed, but the C compiler chokes. */
/* Read the warning under tmp_number */
NODE *
tmp_string(s, len)
char *s;
int len;
{
	register NODE *r;

	r = make_string(s, len);
	r->flags |= TEMP;
	return r;
}