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 #include <stdlib.h> 34 #include "shell.h" 35 #include "output.h" 36 #include "error.h" 37 #include "memalloc.h" 38 #include "mystring.h" 39 #include "alias.h" 40 #include "options.h" 41 #include "builtins.h" 42 43 #define ATABSIZE 39 44 45 static struct alias *atab[ATABSIZE]; 46 static int aliases; 47 48 static void setalias(const char *, const char *); 49 static int unalias(const char *); 50 static size_t hashalias(const char *); 51 52 static 53 void 54 setalias(const char *name, const char *val) 55 { 56 struct alias *ap, **app; 57 58 unalias(name); 59 app = &atab[hashalias(name)]; 60 INTOFF; 61 ap = ckmalloc(sizeof (struct alias)); 62 ap->name = savestr(name); 63 ap->val = savestr(val); 64 ap->flag = 0; 65 ap->next = *app; 66 *app = ap; 67 aliases++; 68 INTON; 69 } 70 71 static void 72 freealias(struct alias *ap) 73 { 74 ckfree(ap->name); 75 ckfree(ap->val); 76 ckfree(ap); 77 } 78 79 static int 80 unalias(const char *name) 81 { 82 struct alias *ap, **app; 83 84 app = &atab[hashalias(name)]; 85 86 for (ap = *app; ap; app = &(ap->next), ap = ap->next) { 87 if (equal(name, ap->name)) { 88 /* 89 * if the alias is currently in use (i.e. its 90 * buffer is being used by the input routine) we 91 * just null out the name instead of freeing it. 92 * We could clear it out later, but this situation 93 * is so rare that it hardly seems worth it. 94 */ 95 if (ap->flag & ALIASINUSE) 96 *ap->name = '\0'; 97 else { 98 INTOFF; 99 *app = ap->next; 100 freealias(ap); 101 INTON; 102 } 103 aliases--; 104 return (0); 105 } 106 } 107 108 return (1); 109 } 110 111 static void 112 rmaliases(void) 113 { 114 struct alias *ap, **app; 115 int i; 116 117 INTOFF; 118 for (i = 0; i < ATABSIZE; i++) { 119 app = &atab[i]; 120 while (*app) { 121 ap = *app; 122 if (ap->flag & ALIASINUSE) { 123 *ap->name = '\0'; 124 app = &(*app)->next; 125 } else { 126 *app = ap->next; 127 freealias(ap); 128 } 129 } 130 } 131 aliases = 0; 132 INTON; 133 } 134 135 struct alias * 136 lookupalias(const char *name, int check) 137 { 138 struct alias *ap; 139 140 if (aliases == 0) 141 return (NULL); 142 for (ap = atab[hashalias(name)]; ap; ap = ap->next) { 143 if (equal(name, ap->name)) { 144 if (check && (ap->flag & ALIASINUSE)) 145 return (NULL); 146 return (ap); 147 } 148 } 149 150 return (NULL); 151 } 152 153 static int 154 comparealiases(const void *p1, const void *p2) 155 { 156 const struct alias *const *a1 = p1; 157 const struct alias *const *a2 = p2; 158 159 return strcmp((*a1)->name, (*a2)->name); 160 } 161 162 static void 163 printalias(const struct alias *a) 164 { 165 out1fmt("%s=", a->name); 166 out1qstr(a->val); 167 out1c('\n'); 168 } 169 170 static void 171 printaliases(void) 172 { 173 int i, j; 174 struct alias **sorted, *ap; 175 176 INTOFF; 177 sorted = ckmalloc(aliases * sizeof(*sorted)); 178 j = 0; 179 for (i = 0; i < ATABSIZE; i++) 180 for (ap = atab[i]; ap; ap = ap->next) 181 if (*ap->name != '\0') 182 sorted[j++] = ap; 183 qsort(sorted, aliases, sizeof(*sorted), comparealiases); 184 for (i = 0; i < aliases; i++) { 185 printalias(sorted[i]); 186 if (int_pending()) 187 break; 188 } 189 ckfree(sorted); 190 INTON; 191 } 192 193 int 194 aliascmd(int argc __unused, char **argv __unused) 195 { 196 char *n, *v; 197 int ret = 0; 198 struct alias *ap; 199 200 nextopt(""); 201 202 if (*argptr == NULL) { 203 printaliases(); 204 return (0); 205 } 206 while ((n = *argptr++) != NULL) { 207 if ((v = strchr(n+1, '=')) == NULL) /* n+1: funny ksh stuff */ 208 if ((ap = lookupalias(n, 0)) == NULL) { 209 warning("%s: not found", n); 210 ret = 1; 211 } else 212 printalias(ap); 213 else { 214 *v++ = '\0'; 215 setalias(n, v); 216 } 217 } 218 219 return (ret); 220 } 221 222 int 223 unaliascmd(int argc __unused, char **argv __unused) 224 { 225 int i; 226 227 while ((i = nextopt("a")) != '\0') { 228 if (i == 'a') { 229 rmaliases(); 230 return (0); 231 } 232 } 233 for (i = 0; *argptr; argptr++) 234 i |= unalias(*argptr); 235 236 return (i); 237 } 238 239 static size_t 240 hashalias(const char *p) 241 { 242 unsigned int hashval; 243 244 hashval = (unsigned char)*p << 4; 245 while (*p) 246 hashval+= *p++; 247 return (hashval % ATABSIZE); 248 } 249 250 const struct alias * 251 iteralias(const struct alias *index) 252 { 253 size_t i = 0; 254 255 if (index != NULL) { 256 if (index->next != NULL) 257 return (index->next); 258 i = hashalias(index->name) + 1; 259 } 260 for (; i < ATABSIZE; i++) 261 if (atab[i] != NULL) 262 return (atab[i]); 263 264 return (NULL); 265 } 266