1/*	$OpenBSD: strings.c,v 1.10 2015/10/16 17:56:07 mmcc Exp $	*/
2/*	$NetBSD: strings.c,v 1.5 1996/06/08 19:48:40 christos Exp $	*/
3
4/*
5 * Copyright (c) 1980, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * Mail -- a mail program
35 *
36 * String allocation routines.
37 * Strings handed out here are reclaimed at the top of the command
38 * loop each time, so they need not be freed.
39 */
40
41#include "rcv.h"
42#include "extern.h"
43
44/*
45 * Allocate size more bytes of space and return the address of the
46 * first byte to the caller.  An even number of bytes are always
47 * allocated so that the space will always be on a word boundary.
48 * The string spaces are of exponentially increasing size, to satisfy
49 * the occasional user with enormous string size requests.
50 */
51char *
52salloc(int size)
53{
54	char *t;
55	int s;
56	struct strings *sp;
57	int index;
58
59	s = size;
60	s += (sizeof(char *) - 1);
61	s &= ~(sizeof(char *) - 1);
62	index = 0;
63	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
64		if (sp->s_topFree == NULL && (STRINGSIZE << index) >= s)
65			break;
66		if (sp->s_nleft >= s)
67			break;
68		index++;
69	}
70	if (sp >= &stringdope[NSPACE])
71		errx(1, "String too large");
72	if (sp->s_topFree == NULL) {
73		index = sp - &stringdope[0];
74		sp->s_topFree = malloc(STRINGSIZE << index);
75		if (sp->s_topFree == NULL)
76			err(1, "malloc");
77		sp->s_nextFree = sp->s_topFree;
78		sp->s_nleft = STRINGSIZE << index;
79	}
80	sp->s_nleft -= s;
81	t = sp->s_nextFree;
82	sp->s_nextFree += s;
83	return(t);
84}
85
86/*
87 * Reset the string area to be empty.
88 * Called to free all strings allocated
89 * since last reset.
90 */
91void
92sreset(void)
93{
94	struct strings *sp;
95	int index;
96
97	if (noreset)
98		return;
99	index = 0;
100	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
101		if (sp->s_topFree == NULL)
102			continue;
103		sp->s_nextFree = sp->s_topFree;
104		sp->s_nleft = STRINGSIZE << index;
105		index++;
106	}
107}
108
109/*
110 * Make the string area permanent.
111 * Meant to be called in main, after initialization.
112 */
113void
114spreserve(void)
115{
116	struct strings *sp;
117
118	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
119		sp->s_topFree = NULL;
120}
121