1 /* $NetBSD: strings.c,v 1.19 2024/03/17 21:48:02 andvar Exp $ */
2
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 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)strings.c 8.1 (Berkeley) 6/6/93";
36 #else
37 __RCSID("$NetBSD: strings.c,v 1.19 2024/03/17 21:48:02 andvar Exp $");
38 #endif
39 #endif /* not lint */
40
41 /*
42 * Mail -- a mail program
43 *
44 * String allocation routines.
45 * Strings handed out here are reclaimed at the top of the command
46 * loop each time, so they need not be freed.
47 */
48
49 #include "rcv.h"
50 #include "extern.h"
51
52 #define STRINGSIZE ((unsigned) 128)/* Dynamic allocation units */
53
54 /*
55 * The pointers for the string allocation routines,
56 * there are NSPACE independent areas.
57 * The first holds STRINGSIZE bytes, the next
58 * twice as much, and so on.
59 */
60 #define NSPACE 25 /* Total number of string spaces */
61 static struct strings {
62 char *s_topFree; /* Beginning of this area */
63 char *s_nextFree; /* Next alloctable place here */
64 size_t s_nleft; /* Number of bytes left here */
65 } stringdope[NSPACE];
66
67 /*
68 * Allocate size more bytes of space and return the address of the
69 * first byte to the caller. An even number of bytes are always
70 * allocated so that the space will always be on a word boundary.
71 * The string spaces are of exponentially increasing size, to satisfy
72 * the occasional user with enormous string size requests.
73 */
74 PUBLIC void *
salloc(size_t size)75 salloc(size_t size)
76 {
77 char *t;
78 size_t s;
79 struct strings *sp;
80 int idx;
81
82 s = size;
83 s += (sizeof(char *) - 1);
84 s &= ~(sizeof(char *) - 1);
85 idx = 0;
86 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
87 if (sp->s_topFree == NULL && (STRINGSIZE << idx) >= s)
88 break;
89 if (sp->s_nleft >= s)
90 break;
91 idx++;
92 }
93 if (sp >= &stringdope[NSPACE])
94 errx(EXIT_FAILURE, "String too large");
95 if (sp->s_topFree == NULL) {
96 idx = (int)(sp - &stringdope[0]);
97 sp->s_topFree = malloc(STRINGSIZE << idx);
98 if (sp->s_topFree == NULL)
99 errx(EXIT_FAILURE, "No room for space %d", idx);
100 sp->s_nextFree = sp->s_topFree;
101 sp->s_nleft = STRINGSIZE << idx;
102 }
103 sp->s_nleft -= s;
104 t = sp->s_nextFree;
105 sp->s_nextFree += s;
106 return t;
107 }
108
109 /*
110 * Allocate zeroed space for 'number' elements of size 'size'.
111 */
112 PUBLIC void *
csalloc(size_t number,size_t size)113 csalloc(size_t number, size_t size)
114 {
115 void *p;
116 p = salloc(number * size);
117 (void)memset(p, 0, number * size);
118 return p;
119 }
120
121 /*
122 * Reset the string area to be empty.
123 * Called to free all strings allocated
124 * since last reset.
125 */
126 PUBLIC void
sreset(void)127 sreset(void)
128 {
129 struct strings *sp;
130 int idx;
131
132 if (noreset)
133 return;
134 idx = 0;
135 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
136 if (sp->s_topFree == NULL)
137 continue;
138 sp->s_nextFree = sp->s_topFree;
139 sp->s_nleft = STRINGSIZE << idx;
140 idx++;
141 }
142 }
143
144 /*
145 * Make the string area permanent.
146 * Meant to be called in main, after initialization.
147 */
148 PUBLIC void
spreserve(void)149 spreserve(void)
150 {
151 struct strings *sp;
152
153 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
154 sp->s_topFree = NULL;
155 }
156