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