alias.c revision 1.12 1 1.12 agc /* $NetBSD: alias.c,v 1.12 2003/08/07 09:05:29 agc Exp $ */
2 1.5 cgd
3 1.1 jtc /*-
4 1.1 jtc * Copyright (c) 1993
5 1.1 jtc * The Regents of the University of California. All rights reserved.
6 1.1 jtc *
7 1.1 jtc * This code is derived from software contributed to Berkeley by
8 1.1 jtc * Kenneth Almquist.
9 1.1 jtc *
10 1.1 jtc * Redistribution and use in source and binary forms, with or without
11 1.1 jtc * modification, are permitted provided that the following conditions
12 1.1 jtc * are met:
13 1.1 jtc * 1. Redistributions of source code must retain the above copyright
14 1.1 jtc * notice, this list of conditions and the following disclaimer.
15 1.1 jtc * 2. Redistributions in binary form must reproduce the above copyright
16 1.1 jtc * notice, this list of conditions and the following disclaimer in the
17 1.1 jtc * documentation and/or other materials provided with the distribution.
18 1.12 agc * 3. Neither the name of the University nor the names of its contributors
19 1.1 jtc * may be used to endorse or promote products derived from this software
20 1.1 jtc * without specific prior written permission.
21 1.1 jtc *
22 1.1 jtc * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 1.1 jtc * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 1.1 jtc * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 1.1 jtc * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 1.1 jtc * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 1.1 jtc * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 1.1 jtc * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 1.1 jtc * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 1.1 jtc * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 1.1 jtc * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 1.1 jtc * SUCH DAMAGE.
33 1.1 jtc */
34 1.1 jtc
35 1.9 christos #include <sys/cdefs.h>
36 1.1 jtc #ifndef lint
37 1.5 cgd #if 0
38 1.6 christos static char sccsid[] = "@(#)alias.c 8.3 (Berkeley) 5/4/95";
39 1.5 cgd #else
40 1.12 agc __RCSID("$NetBSD: alias.c,v 1.12 2003/08/07 09:05:29 agc Exp $");
41 1.5 cgd #endif
42 1.1 jtc #endif /* not lint */
43 1.1 jtc
44 1.6 christos #include <stdlib.h>
45 1.1 jtc #include "shell.h"
46 1.1 jtc #include "input.h"
47 1.1 jtc #include "output.h"
48 1.1 jtc #include "error.h"
49 1.1 jtc #include "memalloc.h"
50 1.1 jtc #include "mystring.h"
51 1.1 jtc #include "alias.h"
52 1.1 jtc #include "options.h" /* XXX for argptr (should remove?) */
53 1.11 christos #include "var.h"
54 1.1 jtc
55 1.1 jtc #define ATABSIZE 39
56 1.1 jtc
57 1.1 jtc struct alias *atab[ATABSIZE];
58 1.1 jtc
59 1.11 christos STATIC void setalias(char *, char *);
60 1.11 christos STATIC int unalias(char *);
61 1.11 christos STATIC struct alias **hashalias(char *);
62 1.1 jtc
63 1.1 jtc STATIC
64 1.4 cgd void
65 1.11 christos setalias(char *name, char *val)
66 1.4 cgd {
67 1.1 jtc struct alias *ap, **app;
68 1.1 jtc
69 1.1 jtc app = hashalias(name);
70 1.1 jtc for (ap = *app; ap; ap = ap->next) {
71 1.1 jtc if (equal(name, ap->name)) {
72 1.1 jtc INTOFF;
73 1.1 jtc ckfree(ap->val);
74 1.1 jtc ap->val = savestr(val);
75 1.1 jtc INTON;
76 1.1 jtc return;
77 1.1 jtc }
78 1.1 jtc }
79 1.1 jtc /* not found */
80 1.1 jtc INTOFF;
81 1.1 jtc ap = ckmalloc(sizeof (struct alias));
82 1.1 jtc ap->name = savestr(name);
83 1.1 jtc /*
84 1.1 jtc * XXX - HACK: in order that the parser will not finish reading the
85 1.1 jtc * alias value off the input before processing the next alias, we
86 1.1 jtc * dummy up an extra space at the end of the alias. This is a crock
87 1.1 jtc * and should be re-thought. The idea (if you feel inclined to help)
88 1.1 jtc * is to avoid alias recursions. The mechanism used is: when
89 1.1 jtc * expanding an alias, the value of the alias is pushed back on the
90 1.1 jtc * input as a string and a pointer to the alias is stored with the
91 1.1 jtc * string. The alias is marked as being in use. When the input
92 1.1 jtc * routine finishes reading the string, it markes the alias not
93 1.1 jtc * in use. The problem is synchronization with the parser. Since
94 1.1 jtc * it reads ahead, the alias is marked not in use before the
95 1.1 jtc * resulting token(s) is next checked for further alias sub. The
96 1.1 jtc * H A C K is that we add a little fluff after the alias value
97 1.1 jtc * so that the string will not be exhausted. This is a good
98 1.1 jtc * idea ------- ***NOT***
99 1.1 jtc */
100 1.1 jtc #ifdef notyet
101 1.1 jtc ap->val = savestr(val);
102 1.1 jtc #else /* hack */
103 1.1 jtc {
104 1.1 jtc int len = strlen(val);
105 1.1 jtc ap->val = ckmalloc(len + 2);
106 1.3 mycroft memcpy(ap->val, val, len);
107 1.1 jtc ap->val[len] = ' '; /* fluff */
108 1.1 jtc ap->val[len+1] = '\0';
109 1.1 jtc }
110 1.1 jtc #endif
111 1.1 jtc ap->next = *app;
112 1.1 jtc *app = ap;
113 1.1 jtc INTON;
114 1.1 jtc }
115 1.1 jtc
116 1.1 jtc STATIC int
117 1.11 christos unalias(char *name)
118 1.11 christos {
119 1.1 jtc struct alias *ap, **app;
120 1.1 jtc
121 1.1 jtc app = hashalias(name);
122 1.1 jtc
123 1.1 jtc for (ap = *app; ap; app = &(ap->next), ap = ap->next) {
124 1.1 jtc if (equal(name, ap->name)) {
125 1.1 jtc /*
126 1.1 jtc * if the alias is currently in use (i.e. its
127 1.1 jtc * buffer is being used by the input routine) we
128 1.1 jtc * just null out the name instead of freeing it.
129 1.1 jtc * We could clear it out later, but this situation
130 1.1 jtc * is so rare that it hardly seems worth it.
131 1.1 jtc */
132 1.1 jtc if (ap->flag & ALIASINUSE)
133 1.1 jtc *ap->name = '\0';
134 1.1 jtc else {
135 1.1 jtc INTOFF;
136 1.1 jtc *app = ap->next;
137 1.1 jtc ckfree(ap->name);
138 1.1 jtc ckfree(ap->val);
139 1.1 jtc ckfree(ap);
140 1.1 jtc INTON;
141 1.1 jtc }
142 1.1 jtc return (0);
143 1.1 jtc }
144 1.1 jtc }
145 1.1 jtc
146 1.1 jtc return (1);
147 1.1 jtc }
148 1.1 jtc
149 1.1 jtc #ifdef mkinit
150 1.11 christos MKINIT void rmaliases(void);
151 1.1 jtc
152 1.1 jtc SHELLPROC {
153 1.1 jtc rmaliases();
154 1.1 jtc }
155 1.1 jtc #endif
156 1.1 jtc
157 1.1 jtc void
158 1.11 christos rmaliases(void)
159 1.11 christos {
160 1.1 jtc struct alias *ap, *tmp;
161 1.1 jtc int i;
162 1.1 jtc
163 1.1 jtc INTOFF;
164 1.1 jtc for (i = 0; i < ATABSIZE; i++) {
165 1.1 jtc ap = atab[i];
166 1.1 jtc atab[i] = NULL;
167 1.1 jtc while (ap) {
168 1.1 jtc ckfree(ap->name);
169 1.1 jtc ckfree(ap->val);
170 1.1 jtc tmp = ap;
171 1.1 jtc ap = ap->next;
172 1.1 jtc ckfree(tmp);
173 1.1 jtc }
174 1.1 jtc }
175 1.1 jtc INTON;
176 1.1 jtc }
177 1.1 jtc
178 1.1 jtc struct alias *
179 1.11 christos lookupalias(char *name, int check)
180 1.4 cgd {
181 1.1 jtc struct alias *ap = *hashalias(name);
182 1.1 jtc
183 1.1 jtc for (; ap; ap = ap->next) {
184 1.1 jtc if (equal(name, ap->name)) {
185 1.1 jtc if (check && (ap->flag & ALIASINUSE))
186 1.1 jtc return (NULL);
187 1.1 jtc return (ap);
188 1.1 jtc }
189 1.1 jtc }
190 1.1 jtc
191 1.1 jtc return (NULL);
192 1.1 jtc }
193 1.1 jtc
194 1.11 christos char *
195 1.11 christos get_alias_text(char *name)
196 1.11 christos {
197 1.11 christos struct alias *ap;
198 1.11 christos
199 1.11 christos ap = lookupalias(name, 0);
200 1.11 christos if (ap == NULL)
201 1.11 christos return NULL;
202 1.11 christos return ap->val;
203 1.11 christos }
204 1.11 christos
205 1.1 jtc /*
206 1.1 jtc * TODO - sort output
207 1.1 jtc */
208 1.4 cgd int
209 1.11 christos aliascmd(int argc, char **argv)
210 1.4 cgd {
211 1.1 jtc char *n, *v;
212 1.1 jtc int ret = 0;
213 1.1 jtc struct alias *ap;
214 1.1 jtc
215 1.1 jtc if (argc == 1) {
216 1.1 jtc int i;
217 1.1 jtc
218 1.1 jtc for (i = 0; i < ATABSIZE; i++)
219 1.1 jtc for (ap = atab[i]; ap; ap = ap->next) {
220 1.11 christos if (*ap->name != '\0') {
221 1.11 christos out1fmt("alias %s=", ap->name);
222 1.11 christos print_quoted(ap->val);
223 1.11 christos out1c('\n');
224 1.11 christos }
225 1.1 jtc }
226 1.1 jtc return (0);
227 1.1 jtc }
228 1.6 christos while ((n = *++argv) != NULL) {
229 1.10 christos if ((v = strchr(n+1, '=')) == NULL) { /* n+1: funny ksh stuff */
230 1.1 jtc if ((ap = lookupalias(n, 0)) == NULL) {
231 1.1 jtc outfmt(out2, "alias: %s not found\n", n);
232 1.1 jtc ret = 1;
233 1.11 christos } else {
234 1.11 christos out1fmt("alias %s=", n);
235 1.11 christos print_quoted(ap->val);
236 1.11 christos out1c('\n');
237 1.11 christos }
238 1.11 christos } else {
239 1.1 jtc *v++ = '\0';
240 1.1 jtc setalias(n, v);
241 1.1 jtc }
242 1.1 jtc }
243 1.1 jtc
244 1.1 jtc return (ret);
245 1.1 jtc }
246 1.1 jtc
247 1.4 cgd int
248 1.11 christos unaliascmd(int argc, char **argv)
249 1.4 cgd {
250 1.1 jtc int i;
251 1.7 christos
252 1.1 jtc while ((i = nextopt("a")) != '\0') {
253 1.1 jtc if (i == 'a') {
254 1.1 jtc rmaliases();
255 1.1 jtc return (0);
256 1.1 jtc }
257 1.1 jtc }
258 1.1 jtc for (i = 0; *argptr; argptr++)
259 1.1 jtc i = unalias(*argptr);
260 1.1 jtc
261 1.1 jtc return (i);
262 1.1 jtc }
263 1.1 jtc
264 1.1 jtc STATIC struct alias **
265 1.11 christos hashalias(char *p)
266 1.11 christos {
267 1.1 jtc unsigned int hashval;
268 1.1 jtc
269 1.1 jtc hashval = *p << 4;
270 1.1 jtc while (*p)
271 1.1 jtc hashval+= *p++;
272 1.1 jtc return &atab[hashval % ATABSIZE];
273 1.1 jtc }
274