1 /*
2 * Copyright (c) 2013-2019 Huawei Technologies Co., Ltd. All rights reserved.
3 * Copyright (c) 2020-2021 Huawei Device Co., Ltd. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without modification,
6 * are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this list of
9 * conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
12 * of conditions and the following disclaimer in the documentation and/or other materials
13 * provided with the distribution.
14 *
15 * 3. Neither the name of the copyright holder nor the names of its contributors may be used
16 * to endorse or promote products derived from this software without specific prior written
17 * permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <stdlib.h>
33 #include <unistd.h>
34 #include <string.h>
35 #include <limits.h>
36 #include <errno.h>
37 #include <sys/stat.h>
38 #include <securec.h>
39
40 /*
41 * LiteOS-M file system uses abs path
42 */
43
vfs_strnlen(const char * str,size_t maxlen)44 static unsigned int vfs_strnlen(const char *str, size_t maxlen)
45 {
46 const char *p = NULL;
47
48 for (p = str; ((maxlen-- != 0) && (*p != '\0')); ++p) {}
49
50 return p - str;
51 }
52
realpath(const char * __restrict path,char * __restrict resolved_path)53 char *realpath(const char *__restrict path, char *__restrict resolved_path)
54 {
55 int namelen;
56 int res;
57 struct stat st;
58
59 if (!*path) {
60 errno = ENOENT;
61 return NULL;
62 }
63
64 namelen = vfs_strnlen(path, PATH_MAX);
65 if (!namelen) {
66 errno = EINVAL;
67 return NULL;
68 } else if (namelen >= PATH_MAX) {
69 errno = ENAMETOOLONG;
70 return NULL;
71 }
72
73 // LiteOS-M file system uses abs path, so we just stat path and strcpy it.
74 if (stat(path, &st) < 0) {
75 errno = ENOENT;
76 return NULL;
77 }
78
79 res = strcpy_s(resolved_path, PATH_MAX, path);
80 if (res != 0) {
81 errno = EINVAL;
82 return NULL;
83 } else {
84 return resolved_path;
85 }
86 }
87