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 __FBSDID("$FreeBSD: head/bin/sh/alias.c 317039 2017-04-16 22:10:02Z jilles $");
40
41 #include <stdlib.h>
42 #include "shell.h"
43 #include "output.h"
44 #include "error.h"
45 #include "memalloc.h"
46 #include "mystring.h"
47 #include "alias.h"
48 #include "options.h"
49 #include "builtins.h"
50
51 #define ATABSIZE 39
52
53 static struct alias *atab[ATABSIZE];
54 static int aliases;
55
56 static void setalias(const char *, const char *);
57 static int unalias(const char *);
58 static struct alias **hashalias(const char *);
59
60 static
61 void
setalias(const char * name,const char * val)62 setalias(const char *name, const char *val)
63 {
64 struct alias *ap, **app;
65
66 unalias(name);
67 app = hashalias(name);
68 INTOFF;
69 ap = ckmalloc(sizeof (struct alias));
70 ap->name = savestr(name);
71 ap->val = savestr(val);
72 ap->flag = 0;
73 ap->next = *app;
74 *app = ap;
75 aliases++;
76 INTON;
77 }
78
79 static void
freealias(struct alias * ap)80 freealias(struct alias *ap)
81 {
82 ckfree(ap->name);
83 ckfree(ap->val);
84 ckfree(ap);
85 }
86
87 static int
unalias(const char * name)88 unalias(const char *name)
89 {
90 struct alias *ap, **app;
91
92 app = hashalias(name);
93
94 for (ap = *app; ap; app = &(ap->next), ap = ap->next) {
95 if (equal(name, ap->name)) {
96 /*
97 * if the alias is currently in use (i.e. its
98 * buffer is being used by the input routine) we
99 * just null out the name instead of freeing it.
100 * We could clear it out later, but this situation
101 * is so rare that it hardly seems worth it.
102 */
103 if (ap->flag & ALIASINUSE)
104 *ap->name = '\0';
105 else {
106 INTOFF;
107 *app = ap->next;
108 freealias(ap);
109 INTON;
110 }
111 aliases--;
112 return (0);
113 }
114 }
115
116 return (1);
117 }
118
119 static void
rmaliases(void)120 rmaliases(void)
121 {
122 struct alias *ap, **app;
123 int i;
124
125 INTOFF;
126 for (i = 0; i < ATABSIZE; i++) {
127 app = &atab[i];
128 while (*app) {
129 ap = *app;
130 if (ap->flag & ALIASINUSE) {
131 *ap->name = '\0';
132 app = &(*app)->next;
133 } else {
134 *app = ap->next;
135 freealias(ap);
136 }
137 }
138 }
139 aliases = 0;
140 INTON;
141 }
142
143 struct alias *
lookupalias(const char * name,int check)144 lookupalias(const char *name, int check)
145 {
146 struct alias *ap;
147
148 if (aliases == 0)
149 return (NULL);
150 for (ap = *hashalias(name); ap; ap = ap->next) {
151 if (equal(name, ap->name)) {
152 if (check && (ap->flag & ALIASINUSE))
153 return (NULL);
154 return (ap);
155 }
156 }
157
158 return (NULL);
159 }
160
161 static int
comparealiases(const void * p1,const void * p2)162 comparealiases(const void *p1, const void *p2)
163 {
164 const struct alias *const *a1 = p1;
165 const struct alias *const *a2 = p2;
166
167 return strcmp((*a1)->name, (*a2)->name);
168 }
169
170 static void
printalias(const struct alias * a)171 printalias(const struct alias *a)
172 {
173 out1fmt("%s=", a->name);
174 out1qstr(a->val);
175 out1c('\n');
176 }
177
178 static void
printaliases(void)179 printaliases(void)
180 {
181 int i, j;
182 struct alias **sorted, *ap;
183
184 INTOFF;
185 sorted = ckmalloc(aliases * sizeof(*sorted));
186 j = 0;
187 for (i = 0; i < ATABSIZE; i++)
188 for (ap = atab[i]; ap; ap = ap->next)
189 if (*ap->name != '\0')
190 sorted[j++] = ap;
191 qsort(sorted, aliases, sizeof(*sorted), comparealiases);
192 for (i = 0; i < aliases; i++) {
193 printalias(sorted[i]);
194 if (int_pending())
195 break;
196 }
197 ckfree(sorted);
198 INTON;
199 }
200
201 int
aliascmd(int argc __unused,char ** argv __unused)202 aliascmd(int argc __unused, char **argv __unused)
203 {
204 char *n, *v;
205 int ret = 0;
206 struct alias *ap;
207
208 nextopt("");
209
210 if (*argptr == NULL) {
211 printaliases();
212 return (0);
213 }
214 while ((n = *argptr++) != NULL) {
215 if ((v = strchr(n+1, '=')) == NULL) /* n+1: funny ksh stuff */
216 if ((ap = lookupalias(n, 0)) == NULL) {
217 warning("%s: not found", n);
218 ret = 1;
219 } else
220 printalias(ap);
221 else {
222 *v++ = '\0';
223 setalias(n, v);
224 }
225 }
226
227 return (ret);
228 }
229
230 int
unaliascmd(int argc __unused,char ** argv __unused)231 unaliascmd(int argc __unused, char **argv __unused)
232 {
233 int i;
234
235 while ((i = nextopt("a")) != '\0') {
236 if (i == 'a') {
237 rmaliases();
238 return (0);
239 }
240 }
241 for (i = 0; *argptr; argptr++)
242 i |= unalias(*argptr);
243
244 return (i);
245 }
246
247 static struct alias **
hashalias(const char * p)248 hashalias(const char *p)
249 {
250 unsigned int hashval;
251
252 hashval = (unsigned char)*p << 4;
253 while (*p)
254 hashval+= *p++;
255 return &atab[hashval % ATABSIZE];
256 }
257