xref: /netbsd-src/usr.bin/mail/strings.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: strings.c,v 1.5 1996/06/08 19:48:40 christos 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 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)strings.c	8.1 (Berkeley) 6/6/93";
39 #else
40 static char rcsid[] = "$NetBSD: strings.c,v 1.5 1996/06/08 19:48:40 christos Exp $";
41 #endif
42 #endif /* not lint */
43 
44 /*
45  * Mail -- a mail program
46  *
47  * String allocation routines.
48  * Strings handed out here are reclaimed at the top of the command
49  * loop each time, so they need not be freed.
50  */
51 
52 #include "rcv.h"
53 #include "extern.h"
54 
55 /*
56  * Allocate size more bytes of space and return the address of the
57  * first byte to the caller.  An even number of bytes are always
58  * allocated so that the space will always be on a word boundary.
59  * The string spaces are of exponentially increasing size, to satisfy
60  * the occasional user with enormous string size requests.
61  */
62 
63 char *
64 salloc(size)
65 	int size;
66 {
67 	register char *t;
68 	register int s;
69 	register struct strings *sp;
70 	int index;
71 
72 	s = size;
73 	s += (sizeof (char *) - 1);
74 	s &= ~(sizeof (char *) - 1);
75 	index = 0;
76 	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
77 		if (sp->s_topFree == NOSTR && (STRINGSIZE << index) >= s)
78 			break;
79 		if (sp->s_nleft >= s)
80 			break;
81 		index++;
82 	}
83 	if (sp >= &stringdope[NSPACE])
84 		panic("String too large");
85 	if (sp->s_topFree == NOSTR) {
86 		index = sp - &stringdope[0];
87 		sp->s_topFree = malloc(STRINGSIZE << index);
88 		if (sp->s_topFree == NOSTR) {
89 			fprintf(stderr, "No room for space %d\n", index);
90 			panic("Internal error");
91 		}
92 		sp->s_nextFree = sp->s_topFree;
93 		sp->s_nleft = STRINGSIZE << index;
94 	}
95 	sp->s_nleft -= s;
96 	t = sp->s_nextFree;
97 	sp->s_nextFree += s;
98 	return(t);
99 }
100 
101 /*
102  * Reset the string area to be empty.
103  * Called to free all strings allocated
104  * since last reset.
105  */
106 void
107 sreset()
108 {
109 	register struct strings *sp;
110 	register int index;
111 
112 	if (noreset)
113 		return;
114 	index = 0;
115 	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
116 		if (sp->s_topFree == NOSTR)
117 			continue;
118 		sp->s_nextFree = sp->s_topFree;
119 		sp->s_nleft = STRINGSIZE << index;
120 		index++;
121 	}
122 }
123 
124 /*
125  * Make the string area permanent.
126  * Meant to be called in main, after initialization.
127  */
128 void
129 spreserve()
130 {
131 	register struct strings *sp;
132 
133 	for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
134 		sp->s_topFree = NOSTR;
135 }
136