1 /* $NetBSD: vars.c,v 1.18 2007/10/27 15:14:51 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[] = "@(#)vars.c 8.1 (Berkeley) 6/6/93"; 36 #else 37 __RCSID("$NetBSD: vars.c,v 1.18 2007/10/27 15:14:51 christos Exp $"); 38 #endif 39 #endif /* not lint */ 40 41 #include "rcv.h" 42 #include <util.h> 43 44 #include "extern.h" 45 46 /* 47 * Mail -- a mail program 48 * 49 * Variable handling stuff. 50 */ 51 52 /* 53 * Free up a variable string. We do not bother to allocate 54 * strings whose value is "" since they are expected to be frequent. 55 * Thus, we cannot free same! 56 */ 57 PUBLIC void 58 v_free(char *cp) 59 { 60 if (*cp) 61 free(cp); 62 } 63 64 /* 65 * Copy a variable value into permanent (ie, not collected after each 66 * command) space. Do not bother to alloc space for "" 67 */ 68 PUBLIC char * 69 vcopy(const char str[]) 70 { 71 char *new; 72 size_t len; 73 74 if (*str == '\0') 75 return estrdup(""); 76 len = strlen(str) + 1; 77 new = emalloc(len); 78 (void)memmove(new, str, len); 79 return new; 80 } 81 82 /* 83 * Hash the passed string and return an index into 84 * the variable or group hash table. 85 */ 86 PUBLIC int 87 hash(const char *name) 88 { 89 int h = 0; 90 91 while (*name) { 92 h <<= 2; 93 h += *name++; 94 } 95 if (h < 0 && (h = -h) < 0) 96 h = 0; 97 return h % HSHSIZE; 98 } 99 100 /* 101 * Locate a variable and return its variable 102 * node. 103 */ 104 PUBLIC struct var * 105 lookup(const char name[]) 106 { 107 struct var *vp; 108 109 for (vp = variables[hash(name)]; vp != NULL; vp = vp->v_link) 110 if (*vp->v_name == *name && equal(vp->v_name, name)) 111 return vp; 112 return NULL; 113 } 114 115 /* 116 * Assign a value to a variable. 117 */ 118 PUBLIC void 119 assign(const char name[], const char values[]) 120 { 121 struct var *vp; 122 int h; 123 124 h = hash(name); 125 vp = lookup(name); 126 if (vp == NULL) { 127 vp = ecalloc(1, sizeof(*vp)); 128 vp->v_name = vcopy(name); 129 vp->v_link = variables[h]; 130 variables[h] = vp; 131 } 132 else 133 v_free(vp->v_value); 134 vp->v_value = vcopy(values); 135 } 136 137 /* 138 * Get the value of a variable and return it. 139 * Look in the environment if its not available locally. 140 */ 141 PUBLIC char * 142 value(const char name[]) 143 { 144 struct var *vp; 145 146 if ((vp = lookup(name)) == NULL) 147 return getenv(name); 148 return vp->v_value; 149 } 150 151 /* 152 * Locate a group name and return it. 153 */ 154 PUBLIC struct grouphead * 155 findgroup(const char name[]) 156 { 157 struct grouphead *gh; 158 159 for (gh = groups[hash(name)]; gh != NULL; gh = gh->g_link) 160 if (*gh->g_name == *name && equal(gh->g_name, name)) 161 return gh; 162 return NULL; 163 } 164 165 /* 166 * Print a group out on stdout 167 */ 168 PUBLIC void 169 printgroup(const char name[]) 170 { 171 struct grouphead *gh; 172 struct group *gp; 173 174 if ((gh = findgroup(name)) == NULL) { 175 (void)printf("\"%s\": not a group\n", name); 176 return; 177 } 178 (void)printf("%s\t", gh->g_name); 179 for (gp = gh->g_list; gp != NULL; gp = gp->ge_link) 180 (void)printf(" %s", gp->ge_name); 181 (void)putchar('\n'); 182 } 183