xref: /openbsd-src/usr.bin/mail/strings.c (revision ce7e0fc6a9d74d25b78fb6ad846387717f5172b6)
1 /*	$OpenBSD: strings.c,v 1.7 2001/11/21 15:26:39 millert 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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 #if 0
39 static const char sccsid[] = "@(#)strings.c	8.1 (Berkeley) 6/6/93";
40 #else
41 static const char rcsid[] = "$OpenBSD: strings.c,v 1.7 2001/11/21 15:26:39 millert 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 char *
64 salloc(int size)
65 {
66 	char *t;
67 	int s;
68 	struct strings *sp;
69 	int index;
70 
71 	s = size;
72 	s += (sizeof(char *) - 1);
73 	s &= ~(sizeof(char *) - 1);
74 	index = 0;
75 	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
76 		if (sp->s_topFree == NULL && (STRINGSIZE << index) >= s)
77 			break;
78 		if (sp->s_nleft >= s)
79 			break;
80 		index++;
81 	}
82 	if (sp >= &stringdope[NSPACE])
83 		errx(1, "String too large");
84 	if (sp->s_topFree == NULL) {
85 		index = sp - &stringdope[0];
86 		sp->s_topFree = (char *)malloc(STRINGSIZE << index);
87 		if (sp->s_topFree == NULL)
88 			errx(1, "No room for space %d", index);
89 		sp->s_nextFree = sp->s_topFree;
90 		sp->s_nleft = STRINGSIZE << index;
91 	}
92 	sp->s_nleft -= s;
93 	t = sp->s_nextFree;
94 	sp->s_nextFree += s;
95 	return(t);
96 }
97 
98 /*
99  * Reset the string area to be empty.
100  * Called to free all strings allocated
101  * since last reset.
102  */
103 void
104 sreset(void)
105 {
106 	struct strings *sp;
107 	int index;
108 
109 	if (noreset)
110 		return;
111 	index = 0;
112 	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
113 		if (sp->s_topFree == NULL)
114 			continue;
115 		sp->s_nextFree = sp->s_topFree;
116 		sp->s_nleft = STRINGSIZE << index;
117 		index++;
118 	}
119 }
120 
121 /*
122  * Make the string area permanent.
123  * Meant to be called in main, after initialization.
124  */
125 void
126 spreserve(void)
127 {
128 	struct strings *sp;
129 
130 	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
131 		sp->s_topFree = NULL;
132 }
133