1/*
2 * implement arrays for dc
3 *
4 * Copyright (C) 1994, 1997, 1998 Free Software Foundation, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2, or (at your option)
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, you can either send email to this
18 * program's author (see below) or write to:
19 *
20 *    The Free Software Foundation, Inc.
21 *    59 Temple Place, Suite 330
22 *    Boston, MA 02111 USA
23 */
24
25/* This module is the only one that knows what arrays look like. */
26
27#include "config.h"
28
29#include <stdio.h>	/* "dc-proto.h" wants this */
30#ifdef HAVE_STDLIB_H
31/* get size_t definition from "almost ANSI" compiling environments. */
32#include <stdlib.h>
33#endif
34#include "dc.h"
35#include "dc-proto.h"
36#include "dc-regdef.h"
37
38/* what's most useful: quick access or sparse arrays? */
39/* I'll go with sparse arrays for now */
40struct dc_array {
41	int Index;
42	dc_data value;
43	struct dc_array *next;
44};
45
46
47/* initialize the arrays */
48void
49dc_array_init DC_DECLVOID()
50{
51}
52
53/* store value into array_id[Index] */
54void
55dc_array_set DC_DECLARG((array_id, Index, value))
56	int array_id DC_DECLSEP
57	int Index DC_DECLSEP
58	dc_data value DC_DECLEND
59{
60	struct dc_array *cur;
61	struct dc_array *prev=NULL;
62	struct dc_array *newentry;
63
64	cur = dc_get_stacked_array(array_id);
65	while (cur && cur->Index < Index){
66		prev = cur;
67		cur = cur->next;
68	}
69	if (cur && cur->Index == Index){
70		if (cur->value.dc_type == DC_NUMBER)
71			dc_free_num(&cur->value.v.number);
72		else if (cur->value.dc_type == DC_STRING)
73			dc_free_str(&cur->value.v.string);
74		else
75			dc_garbage(" in array", array_id);
76		cur->value = value;
77	}else{
78		newentry = dc_malloc(sizeof *newentry);
79		newentry->Index = Index;
80		newentry->value = value;
81		newentry->next = cur;
82		if (prev)
83			prev->next = newentry;
84		else
85			dc_set_stacked_array(array_id, newentry);
86	}
87}
88
89/* retrieve a dup of a value from array_id[Index] */
90/* A zero value is returned if the specified value is unintialized. */
91dc_data
92dc_array_get DC_DECLARG((array_id, Index))
93	int array_id DC_DECLSEP
94	int Index DC_DECLEND
95{
96	struct dc_array *cur;
97
98	for (cur=dc_get_stacked_array(array_id); cur; cur=cur->next)
99		if (cur->Index == Index)
100			return dc_dup(cur->value);
101	return dc_int2data(0);
102}
103
104/* free an array chain */
105void
106dc_array_free DC_DECLARG((a_head))
107	struct dc_array *a_head DC_DECLEND
108{
109	struct dc_array *cur;
110	struct dc_array *next;
111
112	for (cur=a_head; cur; cur=next) {
113		next = cur->next;
114		if (cur->value.dc_type == DC_NUMBER)
115			dc_free_num(&cur->value.v.number);
116		else if (cur->value.dc_type == DC_STRING)
117			dc_free_str(&cur->value.v.string);
118		else
119			dc_garbage("in stack", -1);
120		free(cur);
121	}
122}
123