strings.c revision 1.8 1 /* $NetBSD: strings.c,v 1.8 2002/03/02 15:27:52 wiz 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. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)strings.c 8.1 (Berkeley) 6/6/93";
40 #else
41 __RCSID("$NetBSD: strings.c,v 1.8 2002/03/02 15:27:52 wiz Exp $");
42 #endif
43 #endif /* not lint */
44
45 /*
46 * Mail -- a mail program
47 *
48 * String allocation routines.
49 * Strings handed out here are reclaimed at the top of the command
50 * loop each time, so they need not be freed.
51 */
52
53 #include "rcv.h"
54 #include "extern.h"
55
56 /*
57 * Allocate size more bytes of space and return the address of the
58 * first byte to the caller. An even number of bytes are always
59 * allocated so that the space will always be on a word boundary.
60 * The string spaces are of exponentially increasing size, to satisfy
61 * the occasional user with enormous string size requests.
62 */
63
64 char *
65 salloc(int size)
66 {
67 char *t;
68 int s;
69 struct strings *sp;
70 int idx;
71
72 s = size;
73 s += (sizeof (char *) - 1);
74 s &= ~(sizeof (char *) - 1);
75 idx = 0;
76 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
77 if (sp->s_topFree == NOSTR && (STRINGSIZE << idx) >= s)
78 break;
79 if (sp->s_nleft >= s)
80 break;
81 idx++;
82 }
83 if (sp >= &stringdope[NSPACE])
84 errx(1, "String too large");
85 if (sp->s_topFree == NOSTR) {
86 idx = sp - &stringdope[0];
87 sp->s_topFree = malloc(STRINGSIZE << idx);
88 if (sp->s_topFree == NOSTR)
89 errx(1, "No room for space %d", idx);
90 sp->s_nextFree = sp->s_topFree;
91 sp->s_nleft = STRINGSIZE << idx;
92 }
93 sp->s_nleft -= s;
94 t = sp->s_nextFree;
95 sp->s_nextFree += s;
96 return(t);
97 }
98
99 /*
100 * Reset the string area to be empty.
101 * Called to free all strings allocated
102 * since last reset.
103 */
104 void
105 sreset(void)
106 {
107 struct strings *sp;
108 int idx;
109
110 if (noreset)
111 return;
112 idx = 0;
113 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
114 if (sp->s_topFree == NOSTR)
115 continue;
116 sp->s_nextFree = sp->s_topFree;
117 sp->s_nleft = STRINGSIZE << idx;
118 idx++;
119 }
120 }
121
122 /*
123 * Make the string area permanent.
124 * Meant to be called in main, after initialization.
125 */
126 void
127 spreserve(void)
128 {
129 struct strings *sp;
130
131 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
132 sp->s_topFree = NOSTR;
133 }
134