1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <stdlib.h> 36 #include "shell.h" 37 #include "output.h" 38 #include "error.h" 39 #include "memalloc.h" 40 #include "mystring.h" 41 #include "alias.h" 42 #include "options.h" 43 #include "builtins.h" 44 45 #define ATABSIZE 39 46 47 static struct alias *atab[ATABSIZE]; 48 static int aliases; 49 50 static void setalias(const char *, const char *); 51 static int unalias(const char *); 52 static size_t hashalias(const char *); 53 54 static 55 void 56 setalias(const char *name, const char *val) 57 { 58 struct alias *ap, **app; 59 60 unalias(name); 61 app = &atab[hashalias(name)]; 62 INTOFF; 63 ap = ckmalloc(sizeof (struct alias)); 64 ap->name = savestr(name); 65 ap->val = savestr(val); 66 ap->flag = 0; 67 ap->next = *app; 68 *app = ap; 69 aliases++; 70 INTON; 71 } 72 73 static void 74 freealias(struct alias *ap) 75 { 76 ckfree(ap->name); 77 ckfree(ap->val); 78 ckfree(ap); 79 } 80 81 static int 82 unalias(const char *name) 83 { 84 struct alias *ap, **app; 85 86 app = &atab[hashalias(name)]; 87 88 for (ap = *app; ap; app = &(ap->next), ap = ap->next) { 89 if (equal(name, ap->name)) { 90 /* 91 * if the alias is currently in use (i.e. its 92 * buffer is being used by the input routine) we 93 * just null out the name instead of freeing it. 94 * We could clear it out later, but this situation 95 * is so rare that it hardly seems worth it. 96 */ 97 if (ap->flag & ALIASINUSE) 98 *ap->name = '\0'; 99 else { 100 INTOFF; 101 *app = ap->next; 102 freealias(ap); 103 INTON; 104 } 105 aliases--; 106 return (0); 107 } 108 } 109 110 return (1); 111 } 112 113 static void 114 rmaliases(void) 115 { 116 struct alias *ap, **app; 117 int i; 118 119 INTOFF; 120 for (i = 0; i < ATABSIZE; i++) { 121 app = &atab[i]; 122 while (*app) { 123 ap = *app; 124 if (ap->flag & ALIASINUSE) { 125 *ap->name = '\0'; 126 app = &(*app)->next; 127 } else { 128 *app = ap->next; 129 freealias(ap); 130 } 131 } 132 } 133 aliases = 0; 134 INTON; 135 } 136 137 struct alias * 138 lookupalias(const char *name, int check) 139 { 140 struct alias *ap; 141 142 if (aliases == 0) 143 return (NULL); 144 for (ap = atab[hashalias(name)]; ap; ap = ap->next) { 145 if (equal(name, ap->name)) { 146 if (check && (ap->flag & ALIASINUSE)) 147 return (NULL); 148 return (ap); 149 } 150 } 151 152 return (NULL); 153 } 154 155 static int 156 comparealiases(const void *p1, const void *p2) 157 { 158 const struct alias *const *a1 = p1; 159 const struct alias *const *a2 = p2; 160 161 return strcmp((*a1)->name, (*a2)->name); 162 } 163 164 static void 165 printalias(const struct alias *a) 166 { 167 out1fmt("%s=", a->name); 168 out1qstr(a->val); 169 out1c('\n'); 170 } 171 172 static void 173 printaliases(void) 174 { 175 int i, j; 176 struct alias **sorted, *ap; 177 178 INTOFF; 179 sorted = ckmalloc(aliases * sizeof(*sorted)); 180 j = 0; 181 for (i = 0; i < ATABSIZE; i++) 182 for (ap = atab[i]; ap; ap = ap->next) 183 if (*ap->name != '\0') 184 sorted[j++] = ap; 185 qsort(sorted, aliases, sizeof(*sorted), comparealiases); 186 for (i = 0; i < aliases; i++) { 187 printalias(sorted[i]); 188 if (int_pending()) 189 break; 190 } 191 ckfree(sorted); 192 INTON; 193 } 194 195 int 196 aliascmd(int argc __unused, char **argv __unused) 197 { 198 char *n, *v; 199 int ret = 0; 200 struct alias *ap; 201 202 nextopt(""); 203 204 if (*argptr == NULL) { 205 printaliases(); 206 return (0); 207 } 208 while ((n = *argptr++) != NULL) { 209 if (n[0] == '\0') { 210 warning("'': not found"); 211 ret = 1; 212 continue; 213 } 214 if ((v = strchr(n+1, '=')) == NULL) /* n+1: funny ksh stuff */ 215 if ((ap = lookupalias(n, 0)) == NULL) { 216 warning("%s: not found", n); 217 ret = 1; 218 } else 219 printalias(ap); 220 else { 221 *v++ = '\0'; 222 setalias(n, v); 223 } 224 } 225 226 return (ret); 227 } 228 229 int 230 unaliascmd(int argc __unused, char **argv __unused) 231 { 232 int i; 233 234 while ((i = nextopt("a")) != '\0') { 235 if (i == 'a') { 236 rmaliases(); 237 return (0); 238 } 239 } 240 for (i = 0; *argptr; argptr++) 241 i |= unalias(*argptr); 242 243 return (i); 244 } 245 246 static size_t 247 hashalias(const char *p) 248 { 249 unsigned int hashval; 250 251 hashval = (unsigned char)*p << 4; 252 while (*p) 253 hashval+= *p++; 254 return (hashval % ATABSIZE); 255 } 256 257 const struct alias * 258 iteralias(const struct alias *index) 259 { 260 size_t i = 0; 261 262 if (index != NULL) { 263 if (index->next != NULL) 264 return (index->next); 265 i = hashalias(index->name) + 1; 266 } 267 for (; i < ATABSIZE; i++) 268 if (atab[i] != NULL) 269 return (atab[i]); 270 271 return (NULL); 272 } 273