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 struct alias **hashalias(const char *);
57
58 static
59 void
setalias(const char * name,const char * val)60 setalias(const char *name, const char *val)
61 {
62 struct alias *ap, **app;
63
64 unalias(name);
65 app = 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
freealias(struct alias * ap)78 freealias(struct alias *ap)
79 {
80 ckfree(ap->name);
81 ckfree(ap->val);
82 ckfree(ap);
83 }
84
85 static int
unalias(const char * name)86 unalias(const char *name)
87 {
88 struct alias *ap, **app;
89
90 app = 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
rmaliases(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 *
lookupalias(const char * name,int check)142 lookupalias(const char *name, int check)
143 {
144 struct alias *ap;
145
146 if (aliases == 0)
147 return (NULL);
148 for (ap = *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
comparealiases(const void * p1,const void * p2)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
printalias(const struct alias * a)169 printalias(const struct alias *a)
170 {
171 out1fmt("%s=", a->name);
172 out1qstr(a->val);
173 out1c('\n');
174 }
175
176 static void
printaliases(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
aliascmd(int argc __unused,char ** argv __unused)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
unaliascmd(int argc __unused,char ** argv __unused)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 struct alias **
hashalias(const char * p)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 &atab[hashval % ATABSIZE];
254 }
255