1 /* $NetBSD: gc.c,v 1.1.1.1 2016/01/14 00:11:29 christos Exp $ */
2
3 /* gc.c -- Functions to remember and garbage collect unused node contents.
4 Id: gc.c,v 1.3 2004/04/11 17:56:45 karl Exp
5
6 Copyright (C) 1993, 2004 Free Software Foundation, Inc.
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
11 any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21
22 Written by Brian Fox (bfox@ai.mit.edu). */
23
24 #include "info.h"
25
26 /* Array of pointers to the contents of gc-able nodes. A pointer on this
27 list can be garbage collected when no info window contains a node whose
28 contents member match the pointer. */
29 static char **gcable_pointers = (char **)NULL;
30 static int gcable_pointers_index = 0;
31 static int gcable_pointers_slots = 0;
32
33 /* Add POINTER to the list of garbage collectible pointers. A pointer
34 is not actually garbage collected until no info window contains a node
35 whose contents member is equal to the pointer. */
36 void
add_gcable_pointer(char * pointer)37 add_gcable_pointer (char *pointer)
38 {
39 gc_pointers ();
40 add_pointer_to_array (pointer, gcable_pointers_index, gcable_pointers,
41 gcable_pointers_slots, 10, char *);
42 }
43
44 /* Grovel the list of info windows and gc-able pointers finding those
45 node->contents which are collectible, and free them. */
46 void
gc_pointers(void)47 gc_pointers (void)
48 {
49 register int i, j, k;
50 INFO_WINDOW *iw;
51 char **new = (char **)NULL;
52 int new_index = 0;
53 int new_slots = 0;
54
55 if (!info_windows || !gcable_pointers_index)
56 return;
57
58 for (i = 0; (iw = info_windows[i]); i++)
59 {
60 for (j = 0; j < iw->nodes_index; j++)
61 {
62 NODE *node = iw->nodes[j];
63
64 /* If this node->contents appears in our list of gcable_pointers,
65 it is not gc-able, so save it. */
66 for (k = 0; k < gcable_pointers_index; k++)
67 if (gcable_pointers[k] == node->contents)
68 {
69 add_pointer_to_array
70 (node->contents, new_index, new, new_slots, 10, char *);
71 break;
72 }
73 }
74 }
75
76 /* We have gathered all of the pointers which need to be saved. Free any
77 of the original pointers which do not appear in the new list. */
78 for (i = 0; i < gcable_pointers_index; i++)
79 {
80 for (j = 0; j < new_index; j++)
81 if (gcable_pointers[i] == new[j])
82 break;
83
84 /* If we got all the way through the new list, then the old pointer
85 can be garbage collected. */
86 if (new && !new[j])
87 free (gcable_pointers[i]);
88 }
89
90 free (gcable_pointers);
91 gcable_pointers = new;
92 gcable_pointers_slots = new_slots;
93 gcable_pointers_index = new_index;
94 }
95