1 /*- 2 * Copyright (c) 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 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. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)alias.c 8.3 (Berkeley) 5/4/95"; 36 #endif 37 #endif /* not lint */ 38 #include <sys/cdefs.h> 39 #include <stdlib.h> 40 #include "shell.h" 41 #include "output.h" 42 #include "error.h" 43 #include "memalloc.h" 44 #include "mystring.h" 45 #include "alias.h" 46 #include "options.h" 47 #include "builtins.h" 48 49 #define ATABSIZE 39 50 51 static struct alias *atab[ATABSIZE]; 52 static int aliases; 53 54 static void setalias(const char *, const char *); 55 static int unalias(const char *); 56 static size_t hashalias(const char *); 57 58 static 59 void 60 setalias(const char *name, const char *val) 61 { 62 struct alias *ap, **app; 63 64 unalias(name); 65 app = &atab[hashalias(name)]; 66 INTOFF; 67 ap = ckmalloc(sizeof (struct alias)); 68 ap->name = savestr(name); 69 ap->val = savestr(val); 70 ap->flag = 0; 71 ap->next = *app; 72 *app = ap; 73 aliases++; 74 INTON; 75 } 76 77 static void 78 freealias(struct alias *ap) 79 { 80 ckfree(ap->name); 81 ckfree(ap->val); 82 ckfree(ap); 83 } 84 85 static int 86 unalias(const char *name) 87 { 88 struct alias *ap, **app; 89 90 app = &atab[hashalias(name)]; 91 92 for (ap = *app; ap; app = &(ap->next), ap = ap->next) { 93 if (equal(name, ap->name)) { 94 /* 95 * if the alias is currently in use (i.e. its 96 * buffer is being used by the input routine) we 97 * just null out the name instead of freeing it. 98 * We could clear it out later, but this situation 99 * is so rare that it hardly seems worth it. 100 */ 101 if (ap->flag & ALIASINUSE) 102 *ap->name = '\0'; 103 else { 104 INTOFF; 105 *app = ap->next; 106 freealias(ap); 107 INTON; 108 } 109 aliases--; 110 return (0); 111 } 112 } 113 114 return (1); 115 } 116 117 static void 118 rmaliases(void) 119 { 120 struct alias *ap, **app; 121 int i; 122 123 INTOFF; 124 for (i = 0; i < ATABSIZE; i++) { 125 app = &atab[i]; 126 while (*app) { 127 ap = *app; 128 if (ap->flag & ALIASINUSE) { 129 *ap->name = '\0'; 130 app = &(*app)->next; 131 } else { 132 *app = ap->next; 133 freealias(ap); 134 } 135 } 136 } 137 aliases = 0; 138 INTON; 139 } 140 141 struct alias * 142 lookupalias(const char *name, int check) 143 { 144 struct alias *ap; 145 146 if (aliases == 0) 147 return (NULL); 148 for (ap = atab[hashalias(name)]; ap; ap = ap->next) { 149 if (equal(name, ap->name)) { 150 if (check && (ap->flag & ALIASINUSE)) 151 return (NULL); 152 return (ap); 153 } 154 } 155 156 return (NULL); 157 } 158 159 static int 160 comparealiases(const void *p1, const void *p2) 161 { 162 const struct alias *const *a1 = p1; 163 const struct alias *const *a2 = p2; 164 165 return strcmp((*a1)->name, (*a2)->name); 166 } 167 168 static void 169 printalias(const struct alias *a) 170 { 171 out1fmt("%s=", a->name); 172 out1qstr(a->val); 173 out1c('\n'); 174 } 175 176 static void 177 printaliases(void) 178 { 179 int i, j; 180 struct alias **sorted, *ap; 181 182 INTOFF; 183 sorted = ckmalloc(aliases * sizeof(*sorted)); 184 j = 0; 185 for (i = 0; i < ATABSIZE; i++) 186 for (ap = atab[i]; ap; ap = ap->next) 187 if (*ap->name != '\0') 188 sorted[j++] = ap; 189 qsort(sorted, aliases, sizeof(*sorted), comparealiases); 190 for (i = 0; i < aliases; i++) { 191 printalias(sorted[i]); 192 if (int_pending()) 193 break; 194 } 195 ckfree(sorted); 196 INTON; 197 } 198 199 int 200 aliascmd(int argc __unused, char **argv __unused) 201 { 202 char *n, *v; 203 int ret = 0; 204 struct alias *ap; 205 206 nextopt(""); 207 208 if (*argptr == NULL) { 209 printaliases(); 210 return (0); 211 } 212 while ((n = *argptr++) != NULL) { 213 if ((v = strchr(n+1, '=')) == NULL) /* n+1: funny ksh stuff */ 214 if ((ap = lookupalias(n, 0)) == NULL) { 215 warning("%s: not found", n); 216 ret = 1; 217 } else 218 printalias(ap); 219 else { 220 *v++ = '\0'; 221 setalias(n, v); 222 } 223 } 224 225 return (ret); 226 } 227 228 int 229 unaliascmd(int argc __unused, char **argv __unused) 230 { 231 int i; 232 233 while ((i = nextopt("a")) != '\0') { 234 if (i == 'a') { 235 rmaliases(); 236 return (0); 237 } 238 } 239 for (i = 0; *argptr; argptr++) 240 i |= unalias(*argptr); 241 242 return (i); 243 } 244 245 static size_t 246 hashalias(const char *p) 247 { 248 unsigned int hashval; 249 250 hashval = (unsigned char)*p << 4; 251 while (*p) 252 hashval+= *p++; 253 return (hashval % ATABSIZE); 254 } 255 256 const struct alias * 257 iteralias(const struct alias *index) 258 { 259 size_t i = 0; 260 261 if (index != NULL) { 262 if (index->next != NULL) 263 return (index->next); 264 i = hashalias(index->name) + 1; 265 } 266 for (; i < ATABSIZE; i++) 267 if (atab[i] != NULL) 268 return (atab[i]); 269 270 return (NULL); 271 } 272