1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1980, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32/*
33 * Mail -- a mail program
34 *
35 * String allocation routines.
36 * Strings handed out here are reclaimed at the top of the command
37 * loop each time, so they need not be freed.
38 */
39
40#include "rcv.h"
41#include "extern.h"
42
43struct strings stringdope[NSPACE];
44
45/*
46 * Allocate size more bytes of space and return the address of the
47 * first byte to the caller.  An even number of bytes are always
48 * allocated so that the space will always be on a word boundary.
49 * The string spaces are of exponentially increasing size, to satisfy
50 * the occasional user with enormous string size requests.
51 */
52
53char *
54salloc(int size)
55{
56	char *t;
57	int s, index;
58	struct strings *sp;
59
60	s = size;
61	s += (sizeof(char *) - 1);
62	s &= ~(sizeof(char *) - 1);
63	index = 0;
64	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
65		if (sp->s_topFree == NULL && (STRINGSIZE << index) >= s)
66			break;
67		if (sp->s_nleft >= s)
68			break;
69		index++;
70	}
71	if (sp >= &stringdope[NSPACE])
72		errx(1, "String too large");
73	if (sp->s_topFree == NULL) {
74		index = sp - &stringdope[0];
75		if ((sp->s_topFree = malloc(STRINGSIZE << index)) == NULL)
76			err(1, "No room for space %d", index);
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