source: trunk/minix/commands/pax/cache.c@ 21

Last change on this file since 21 was 9, checked in by Mattia Monga, 13 years ago

Minix 3.1.2a
File size: 9.5 KB
Line 
1/*-
2 * Copyright (c) 1992 Keith Muller.
3 * Copyright (c) 1992, 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Keith Muller of the University of California, San Diego.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35#if 0
36static char sccsid[] = "@(#)cache.c 8.1 (Berkeley) 5/31/93";
37#endif
38#endif /* not lint */
39
40#include <sys/types.h>
41#include <sys/stat.h>
42#include <string.h>
43#include <stdio.h>
44#include <pwd.h>
45#include <grp.h>
46#include <unistd.h>
47#include <stdlib.h>
48#include "pax.h"
49#include "cache.h"
50#include "extern.h"
51
52/*
53 * routines that control user, group, uid and gid caches (for the archive
54 * member print routine).
55 * IMPORTANT:
56 * these routines cache BOTH hits and misses, a major performance improvement
57 */
58
59static int pwopn = 0; /* is password file open */
60static int gropn = 0; /* is group file open */
61static UIDC **uidtb = NULL; /* uid to name cache */
62static GIDC **gidtb = NULL; /* gid to name cache */
63static UIDC **usrtb = NULL; /* user name to uid cache */
64static GIDC **grptb = NULL; /* group name to gid cache */
65
66/*
67 * uidtb_start
68 * creates an an empty uidtb
69 * Return:
70 * 0 if ok, -1 otherwise
71 */
72
73int
74uidtb_start(void)
75{
76 static int fail = 0;
77
78 if (uidtb != NULL)
79 return(0);
80 if (fail)
81 return(-1);
82 if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
83 ++fail;
84 paxwarn(1, "Unable to allocate memory for user id cache table");
85 return(-1);
86 }
87 return(0);
88}
89
90/*
91 * gidtb_start
92 * creates an an empty gidtb
93 * Return:
94 * 0 if ok, -1 otherwise
95 */
96
97int
98gidtb_start(void)
99{
100 static int fail = 0;
101
102 if (gidtb != NULL)
103 return(0);
104 if (fail)
105 return(-1);
106 if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
107 ++fail;
108 paxwarn(1, "Unable to allocate memory for group id cache table");
109 return(-1);
110 }
111 return(0);
112}
113
114/*
115 * usrtb_start
116 * creates an an empty usrtb
117 * Return:
118 * 0 if ok, -1 otherwise
119 */
120
121int
122usrtb_start(void)
123{
124 static int fail = 0;
125
126 if (usrtb != NULL)
127 return(0);
128 if (fail)
129 return(-1);
130 if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
131 ++fail;
132 paxwarn(1, "Unable to allocate memory for user name cache table");
133 return(-1);
134 }
135 return(0);
136}
137
138/*
139 * grptb_start
140 * creates an an empty grptb
141 * Return:
142 * 0 if ok, -1 otherwise
143 */
144
145int
146grptb_start(void)
147{
148 static int fail = 0;
149
150 if (grptb != NULL)
151 return(0);
152 if (fail)
153 return(-1);
154 if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
155 ++fail;
156 paxwarn(1,"Unable to allocate memory for group name cache table");
157 return(-1);
158 }
159 return(0);
160}
161
162/*
163 * name_uid()
164 * caches the name (if any) for the uid. If frc set, we always return the
165 * the stored name (if valid or invalid match). We use a simple hash table.
166 * Return
167 * Pointer to stored name (or an empty string).
168 */
169
170const char *
171name_uid(uid_t uid, int frc)
172{
173 struct passwd *pw;
174 UIDC *ptr;
175
176 if ((uidtb == NULL) && (uidtb_start() < 0))
177 return("");
178
179 /*
180 * see if we have this uid cached
181 */
182 ptr = uidtb[uid % UID_SZ];
183 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
184 /*
185 * have an entry for this uid
186 */
187 if (frc || (ptr->valid == VALID))
188 return(ptr->name);
189 return("");
190 }
191
192 /*
193 * No entry for this uid, we will add it
194 */
195 if (!pwopn) {
196 setpassent(1);
197 ++pwopn;
198 }
199 if (ptr == NULL)
200 ptr = uidtb[uid % UID_SZ] = (UIDC *)malloc(sizeof(UIDC));
201
202 if ((pw = getpwuid(uid)) == NULL) {
203 /*
204 * no match for this uid in the local password file
205 * a string that is the uid in numeric format
206 */
207 if (ptr == NULL)
208 return("");
209 ptr->uid = uid;
210 ptr->valid = INVALID;
211# ifdef NET2_STAT
212 (void)snprintf(ptr->name, sizeof(ptr->name), "%u", uid);
213# else
214 (void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
215 (unsigned long)uid);
216# endif
217 if (frc == 0)
218 return("");
219 } else {
220 /*
221 * there is an entry for this uid in the password file
222 */
223 if (ptr == NULL)
224 return(pw->pw_name);
225 ptr->uid = uid;
226 (void)strncpy(ptr->name, pw->pw_name, UNMLEN - 1);
227 ptr->name[UNMLEN-1] = '\0';
228 ptr->valid = VALID;
229 }
230 return(ptr->name);
231}
232
233/*
234 * name_gid()
235 * caches the name (if any) for the gid. If frc set, we always return the
236 * the stored name (if valid or invalid match). We use a simple hash table.
237 * Return
238 * Pointer to stored name (or an empty string).
239 */
240
241const char *
242name_gid(gid_t gid, int frc)
243{
244 struct group *gr;
245 GIDC *ptr;
246
247 if ((gidtb == NULL) && (gidtb_start() < 0))
248 return("");
249
250 /*
251 * see if we have this gid cached
252 */
253 ptr = gidtb[gid % GID_SZ];
254 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
255 /*
256 * have an entry for this gid
257 */
258 if (frc || (ptr->valid == VALID))
259 return(ptr->name);
260 return("");
261 }
262
263 /*
264 * No entry for this gid, we will add it
265 */
266 if (!gropn) {
267 setgroupent(1);
268 ++gropn;
269 }
270 if (ptr == NULL)
271 ptr = gidtb[gid % GID_SZ] = (GIDC *)malloc(sizeof(GIDC));
272
273 if ((gr = getgrgid(gid)) == NULL) {
274 /*
275 * no match for this gid in the local group file, put in
276 * a string that is the gid in numeric format
277 */
278 if (ptr == NULL)
279 return("");
280 ptr->gid = gid;
281 ptr->valid = INVALID;
282# ifdef NET2_STAT
283 (void)snprintf(ptr->name, sizeof(ptr->name), "%u", gid);
284# else
285 (void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
286 (unsigned long)gid);
287# endif
288 if (frc == 0)
289 return("");
290 } else {
291 /*
292 * there is an entry for this group in the group file
293 */
294 if (ptr == NULL)
295 return(gr->gr_name);
296 ptr->gid = gid;
297 (void)strncpy(ptr->name, gr->gr_name, GNMLEN - 1);
298 ptr->name[GNMLEN-1] = '\0';
299 ptr->valid = VALID;
300 }
301 return(ptr->name);
302}
303
304/*
305 * uid_name()
306 * caches the uid for a given user name. We use a simple hash table.
307 * Return
308 * the uid (if any) for a user name, or a -1 if no match can be found
309 */
310
311int
312uid_name(char *name, uid_t *uid)
313{
314 struct passwd *pw;
315 UIDC *ptr;
316 int namelen;
317
318 /*
319 * return -1 for mangled names
320 */
321 if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
322 return(-1);
323 if ((usrtb == NULL) && (usrtb_start() < 0))
324 return(-1);
325
326 /*
327 * look up in hash table, if found and valid return the uid,
328 * if found and invalid, return a -1
329 */
330 ptr = usrtb[st_hash(name, namelen, UNM_SZ)];
331 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
332 if (ptr->valid == INVALID)
333 return(-1);
334 *uid = ptr->uid;
335 return(0);
336 }
337
338 if (!pwopn) {
339 setpassent(1);
340 ++pwopn;
341 }
342
343 if (ptr == NULL)
344 ptr = usrtb[st_hash(name, namelen, UNM_SZ)] =
345 (UIDC *)malloc(sizeof(UIDC));
346
347 /*
348 * no match, look it up, if no match store it as an invalid entry,
349 * or store the matching uid
350 */
351 if (ptr == NULL) {
352 if ((pw = getpwnam(name)) == NULL)
353 return(-1);
354 *uid = pw->pw_uid;
355 return(0);
356 }
357 (void)strncpy(ptr->name, name, UNMLEN - 1);
358 ptr->name[UNMLEN-1] = '\0';
359 if ((pw = getpwnam(name)) == NULL) {
360 ptr->valid = INVALID;
361 return(-1);
362 }
363 ptr->valid = VALID;
364 *uid = ptr->uid = pw->pw_uid;
365 return(0);
366}
367
368/*
369 * gid_name()
370 * caches the gid for a given group name. We use a simple hash table.
371 * Return
372 * the gid (if any) for a group name, or a -1 if no match can be found
373 */
374
375int
376gid_name(char *name, gid_t *gid)
377{
378 struct group *gr;
379 GIDC *ptr;
380 int namelen;
381
382 /*
383 * return -1 for mangled names
384 */
385 if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
386 return(-1);
387 if ((grptb == NULL) && (grptb_start() < 0))
388 return(-1);
389
390 /*
391 * look up in hash table, if found and valid return the uid,
392 * if found and invalid, return a -1
393 */
394 ptr = grptb[st_hash(name, namelen, GID_SZ)];
395 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
396 if (ptr->valid == INVALID)
397 return(-1);
398 *gid = ptr->gid;
399 return(0);
400 }
401
402 if (!gropn) {
403 setgroupent(1);
404 ++gropn;
405 }
406 if (ptr == NULL)
407 ptr = grptb[st_hash(name, namelen, GID_SZ)] =
408 (GIDC *)malloc(sizeof(GIDC));
409
410 /*
411 * no match, look it up, if no match store it as an invalid entry,
412 * or store the matching gid
413 */
414 if (ptr == NULL) {
415 if ((gr = getgrnam(name)) == NULL)
416 return(-1);
417 *gid = gr->gr_gid;
418 return(0);
419 }
420
421 (void)strncpy(ptr->name, name, GNMLEN - 1);
422 ptr->name[GNMLEN-1] = '\0';
423 if ((gr = getgrnam(name)) == NULL) {
424 ptr->valid = INVALID;
425 return(-1);
426 }
427 ptr->valid = VALID;
428 *gid = ptr->gid = gr->gr_gid;
429 return(0);
430}
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