1 /* $NetBSD: strings.c,v 1.16 2007/10/29 23:20:39 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. 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 1.16 2007/10/29 23:20:39 christos 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 unsigned 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 75 PUBLIC void * 76 salloc(size_t size) 77 { 78 char *t; 79 size_t s; 80 struct strings *sp; 81 int idx; 82 83 s = size; 84 s += (sizeof(char *) - 1); 85 s &= ~(sizeof(char *) - 1); 86 idx = 0; 87 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) { 88 if (sp->s_topFree == NULL && (STRINGSIZE << idx) >= s) 89 break; 90 if (sp->s_nleft >= s) 91 break; 92 idx++; 93 } 94 if (sp >= &stringdope[NSPACE]) 95 errx(1, "String too large"); 96 if (sp->s_topFree == NULL) { 97 idx = sp - &stringdope[0]; 98 sp->s_topFree = malloc(STRINGSIZE << idx); 99 if (sp->s_topFree == NULL) 100 errx(1, "No room for space %d", idx); 101 sp->s_nextFree = sp->s_topFree; 102 sp->s_nleft = STRINGSIZE << idx; 103 } 104 sp->s_nleft -= s; 105 t = sp->s_nextFree; 106 sp->s_nextFree += s; 107 return t; 108 } 109 110 /* 111 * Allocate zeroed space for 'number' elments of size 'size'. 112 */ 113 PUBLIC void * 114 csalloc(size_t number, size_t size) 115 { 116 void *p; 117 p = salloc(number * size); 118 (void)memset(p, 0, number * size); 119 return p; 120 } 121 122 /* 123 * Reset the string area to be empty. 124 * Called to free all strings allocated 125 * since last reset. 126 */ 127 PUBLIC void 128 sreset(void) 129 { 130 struct strings *sp; 131 int idx; 132 133 if (noreset) 134 return; 135 idx = 0; 136 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) { 137 if (sp->s_topFree == NULL) 138 continue; 139 sp->s_nextFree = sp->s_topFree; 140 sp->s_nleft = STRINGSIZE << idx; 141 idx++; 142 } 143 } 144 145 /* 146 * Make the string area permanent. 147 * Meant to be called in main, after initialization. 148 */ 149 PUBLIC void 150 spreserve(void) 151 { 152 struct strings *sp; 153 154 for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) 155 sp->s_topFree = NULL; 156 } 157