xref: /freebsd/contrib/ntp/libntp/lib/isc/unix/dir.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*
2  * Copyright (C) 2004, 2005, 2007-2009, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 1999-2001  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id$ */
19 
20 /*! \file
21  * \author  Principal Authors: DCL */
22 
23 #include <config.h>
24 
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 
28 #include <ctype.h>
29 #include <errno.h>
30 #include <unistd.h>
31 
32 #include <isc/dir.h>
33 #include <isc/magic.h>
34 #include <isc/string.h>
35 #include <isc/util.h>
36 
37 #include "errno2result.h"
38 #include "ntp_stdlib.h"		/* NTP change for strlcpy, strlcat */
39 
40 #define ISC_DIR_MAGIC		ISC_MAGIC('D', 'I', 'R', '*')
41 #define VALID_DIR(dir)		ISC_MAGIC_VALID(dir, ISC_DIR_MAGIC)
42 
43 void
44 isc_dir_init(isc_dir_t *dir) {
45 	REQUIRE(dir != NULL);
46 
47 	dir->entry.name[0] = '\0';
48 	dir->entry.length = 0;
49 
50 	dir->handle = NULL;
51 
52 	dir->magic = ISC_DIR_MAGIC;
53 }
54 
55 /*!
56  * \brief Allocate workspace and open directory stream. If either one fails,
57  * NULL will be returned.
58  */
59 isc_result_t
60 isc_dir_open(isc_dir_t *dir, const char *dirname) {
61 	char *p;
62 	size_t octets;
63 	isc_result_t result = ISC_R_SUCCESS;
64 
65 	REQUIRE(VALID_DIR(dir));
66 	REQUIRE(dirname != NULL);
67 
68 	/*
69 	 * Copy directory name.  Need to have enough space for the name,
70 	 * a possible path separator, the wildcard, and the final NUL.
71 	 */
72 	octets = strlen(dirname) + 1;
73 	if (octets + 2 > sizeof(dir->dirname))
74 		/* XXXDCL ? */
75 		return (ISC_R_NOSPACE);
76 	strlcpy(dir->dirname, dirname, octets);
77 
78 	/*
79 	 * Append path separator, if needed, and "*".
80 	 */
81 	p = dir->dirname + strlen(dir->dirname);
82 	if (dir->dirname < p && *(p - 1) != '/')
83 		*p++ = '/';
84 	*p++ = '*';
85 	*p = '\0';
86 
87 	/*
88 	 * Open stream.
89 	 */
90 	dir->handle = opendir(dirname);
91 
92 	if (dir->handle == NULL)
93 		return isc__errno2result(errno);
94 
95 	return (result);
96 }
97 
98 /*!
99  * \brief Return previously retrieved file or get next one.
100 
101  * Unix's dirent has
102  * separate open and read functions, but the Win32 and DOS interfaces open
103  * the dir stream and reads the first file in one operation.
104  */
105 isc_result_t
106 isc_dir_read(isc_dir_t *dir) {
107 	struct dirent *entry;
108 	size_t octets;
109 
110 	REQUIRE(VALID_DIR(dir) && dir->handle != NULL);
111 
112 	/*
113 	 * Fetch next file in directory.
114 	 */
115 	entry = readdir(dir->handle);
116 
117 	if (entry == NULL)
118 		return (ISC_R_NOMORE);
119 
120 	/*
121 	 * Make sure that the space for the name is long enough.
122 	 */
123 	octets = strlen(entry->d_name) + 1;
124 	if (sizeof(dir->entry.name) < octets)
125 		return (ISC_R_UNEXPECTED);
126 
127 	strlcpy(dir->entry.name, entry->d_name, octets);
128 
129 	/*
130 	 * Some dirents have d_namlen, but it is not portable.
131 	 */
132 	dir->entry.length = strlen(entry->d_name);
133 
134 	return (ISC_R_SUCCESS);
135 }
136 
137 /*!
138  * \brief Close directory stream.
139  */
140 void
141 isc_dir_close(isc_dir_t *dir) {
142        REQUIRE(VALID_DIR(dir) && dir->handle != NULL);
143 
144        (void)closedir(dir->handle);
145        dir->handle = NULL;
146 }
147 
148 /*!
149  * \brief Reposition directory stream at start.
150  */
151 isc_result_t
152 isc_dir_reset(isc_dir_t *dir) {
153 	REQUIRE(VALID_DIR(dir) && dir->handle != NULL);
154 
155 	rewinddir(dir->handle);
156 
157 	return (ISC_R_SUCCESS);
158 }
159 
160 isc_result_t
161 isc_dir_chdir(const char *dirname) {
162 	/*!
163 	 * \brief Change the current directory to 'dirname'.
164 	 */
165 
166 	REQUIRE(dirname != NULL);
167 
168 	if (chdir(dirname) < 0)
169 		return (isc__errno2result(errno));
170 
171 	return (ISC_R_SUCCESS);
172 }
173 
174 isc_result_t
175 isc_dir_chroot(const char *dirname) {
176 
177 	REQUIRE(dirname != NULL);
178 
179 #ifdef HAVE_CHROOT
180 	if (chroot(dirname) < 0 || chdir("/") < 0)
181 		return (isc__errno2result(errno));
182 
183 	return (ISC_R_SUCCESS);
184 #else
185 	return (ISC_R_NOTIMPLEMENTED);
186 #endif
187 }
188 
189 isc_result_t
190 isc_dir_createunique(char *templet) {
191 	isc_result_t result;
192 	char *x;
193 	char *p;
194 	int i;
195 	int pid;
196 
197 	REQUIRE(templet != NULL);
198 
199 	/*!
200 	 * \brief mkdtemp is not portable, so this emulates it.
201 	 */
202 
203 	pid = getpid();
204 
205 	/*
206 	 * Replace trailing Xs with the process-id, zero-filled.
207 	 */
208 	for (x = templet + strlen(templet) - 1; *x == 'X' && x >= templet;
209 	     x--, pid /= 10)
210 		*x = pid % 10 + '0';
211 
212 	x++;			/* Set x to start of ex-Xs. */
213 
214 	do {
215 		i = mkdir(templet, 0700);
216 		if (i == 0 || errno != EEXIST)
217 			break;
218 
219 		/*
220 		 * The BSD algorithm.
221 		 */
222 		p = x;
223 		while (*p != '\0') {
224 			if (isdigit(*p & 0xff))
225 				*p = 'a';
226 			else if (*p != 'z')
227 				++*p;
228 			else {
229 				/*
230 				 * Reset character and move to next.
231 				 */
232 				*p++ = 'a';
233 				continue;
234 			}
235 
236 			break;
237 		}
238 
239 		if (*p == '\0') {
240 			/*
241 			 * Tried all combinations.  errno should already
242 			 * be EEXIST, but ensure it is anyway for
243 			 * isc__errno2result().
244 			 */
245 			errno = EEXIST;
246 			break;
247 		}
248 	} while (1);
249 
250 	if (i == -1)
251 		result = isc__errno2result(errno);
252 	else
253 		result = ISC_R_SUCCESS;
254 
255 	return (result);
256 }
257