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Commit | Line | Data |
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de23aa1d TT |
1 | /* |
2 | * finddev.c -- this routine attempts to find a particular device in | |
3 | * /dev | |
efc6f628 | 4 | * |
de23aa1d TT |
5 | * Copyright (C) 2000 Theodore Ts'o. |
6 | * | |
7 | * %Begin-Header% | |
543547a5 TT |
8 | * This file may be redistributed under the terms of the GNU Library |
9 | * General Public License, version 2. | |
de23aa1d TT |
10 | * %End-Header% |
11 | */ | |
12 | ||
d1154eb4 | 13 | #include "config.h" |
de23aa1d TT |
14 | #include <stdio.h> |
15 | #include <string.h> | |
16 | #if HAVE_UNISTD_H | |
17 | #include <unistd.h> | |
18 | #endif | |
19 | #include <stdlib.h> | |
20 | #include <string.h> | |
21 | #if HAVE_SYS_TYPES_H | |
22 | #include <sys/types.h> | |
23 | #endif | |
24 | #if HAVE_SYS_STAT_H | |
25 | #include <sys/stat.h> | |
26 | #endif | |
27 | #include <dirent.h> | |
28 | #if HAVE_ERRNO_H | |
29 | #include <errno.h> | |
30 | #endif | |
31 | #if HAVE_SYS_MKDEV_H | |
32 | #include <sys/mkdev.h> | |
33 | #endif | |
34 | ||
31dbecd4 | 35 | #include "ext2_fs.h" |
31dbecd4 TT |
36 | #include "ext2fs.h" |
37 | ||
de23aa1d TT |
38 | struct dir_list { |
39 | char *name; | |
40 | struct dir_list *next; | |
41 | }; | |
42 | ||
de23aa1d TT |
43 | /* |
44 | * This function adds an entry to the directory list | |
45 | */ | |
31dbecd4 | 46 | static void add_to_dirlist(const char *name, struct dir_list **list) |
de23aa1d TT |
47 | { |
48 | struct dir_list *dp; | |
49 | ||
50 | dp = malloc(sizeof(struct dir_list)); | |
51 | if (!dp) | |
52 | return; | |
53 | dp->name = malloc(strlen(name)+1); | |
54 | if (!dp->name) { | |
55 | free(dp); | |
56 | return; | |
57 | } | |
58 | strcpy(dp->name, name); | |
59 | dp->next = *list; | |
60 | *list = dp; | |
61 | } | |
62 | ||
63 | /* | |
64 | * This function frees a directory list | |
65 | */ | |
66 | static void free_dirlist(struct dir_list **list) | |
67 | { | |
68 | struct dir_list *dp, *next; | |
69 | ||
70 | for (dp = *list; dp; dp = next) { | |
71 | next = dp->next; | |
72 | free(dp->name); | |
73 | free(dp); | |
74 | } | |
75 | *list = 0; | |
76 | } | |
77 | ||
78 | static int scan_dir(char *dirname, dev_t device, struct dir_list **list, | |
79 | char **ret_path) | |
80 | { | |
81 | DIR *dir; | |
82 | struct dirent *dp; | |
83 | char path[1024], *cp; | |
84 | int dirlen; | |
85 | struct stat st; | |
86 | ||
87 | dirlen = strlen(dirname); | |
88 | if ((dir = opendir(dirname)) == NULL) | |
89 | return errno; | |
90 | dp = readdir(dir); | |
91 | while (dp) { | |
92 | if (dirlen + strlen(dp->d_name) + 2 >= sizeof(path)) | |
93 | goto skip_to_next; | |
94 | if (dp->d_name[0] == '.' && | |
95 | ((dp->d_name[1] == 0) || | |
31dbecd4 | 96 | ((dp->d_name[1] == '.') && (dp->d_name[2] == 0)))) |
de23aa1d TT |
97 | goto skip_to_next; |
98 | sprintf(path, "%s/%s", dirname, dp->d_name); | |
99 | if (stat(path, &st) < 0) | |
f86fa6c7 | 100 | goto skip_to_next; |
de23aa1d TT |
101 | if (S_ISDIR(st.st_mode)) |
102 | add_to_dirlist(path, list); | |
103 | if (S_ISBLK(st.st_mode) && st.st_rdev == device) { | |
104 | cp = malloc(strlen(path)+1); | |
3751721f TT |
105 | if (!cp) { |
106 | closedir(dir); | |
de23aa1d | 107 | return ENOMEM; |
3751721f | 108 | } |
de23aa1d TT |
109 | strcpy(cp, path); |
110 | *ret_path = cp; | |
3751721f | 111 | goto success; |
de23aa1d TT |
112 | } |
113 | skip_to_next: | |
114 | dp = readdir(dir); | |
115 | } | |
3751721f | 116 | success: |
de23aa1d TT |
117 | closedir(dir); |
118 | return 0; | |
119 | } | |
120 | ||
121 | /* | |
122 | * This function finds the pathname to a block device with a given | |
123 | * device number. It returns a pointer to allocated memory to the | |
124 | * pathname on success, and NULL on failure. | |
125 | */ | |
126 | char *ext2fs_find_block_device(dev_t device) | |
127 | { | |
128 | struct dir_list *list = 0, *new_list = 0; | |
129 | struct dir_list *current; | |
130 | char *ret_path = 0; | |
131 | ||
132 | /* | |
133 | * Add the starting directories to search... | |
134 | */ | |
135 | add_to_dirlist("/devices", &list); | |
136 | add_to_dirlist("/devfs", &list); | |
137 | add_to_dirlist("/dev", &list); | |
efc6f628 | 138 | |
de23aa1d TT |
139 | while (list) { |
140 | current = list; | |
141 | list = list->next; | |
142 | #ifdef DEBUG | |
143 | printf("Scanning directory %s\n", current->name); | |
144 | #endif | |
145 | scan_dir(current->name, device, &new_list, &ret_path); | |
146 | free(current->name); | |
147 | free(current); | |
148 | if (ret_path) | |
149 | break; | |
150 | /* | |
151 | * If we're done checking at this level, descend to | |
152 | * the next level of subdirectories. (breadth-first) | |
153 | */ | |
154 | if (list == 0) { | |
155 | list = new_list; | |
156 | new_list = 0; | |
157 | } | |
158 | } | |
de23aa1d TT |
159 | free_dirlist(&list); |
160 | free_dirlist(&new_list); | |
161 | return ret_path; | |
162 | } | |
163 | ||
efc6f628 | 164 | |
de23aa1d TT |
165 | #ifdef DEBUG |
166 | int main(int argc, char** argv) | |
167 | { | |
168 | char *devname, *tmp; | |
169 | int major, minor; | |
170 | dev_t device; | |
171 | const char *errmsg = "Couldn't parse %s: %s\n"; | |
172 | ||
173 | if ((argc != 2) && (argc != 3)) { | |
174 | fprintf(stderr, "Usage: %s device_number\n", argv[0]); | |
175 | fprintf(stderr, "\t: %s major minor\n", argv[0]); | |
176 | exit(1); | |
177 | } | |
178 | if (argc == 2) { | |
179 | device = strtoul(argv[1], &tmp, 0); | |
180 | if (*tmp) { | |
181 | fprintf(stderr, errmsg, "device number", argv[1]); | |
182 | exit(1); | |
183 | } | |
184 | } else { | |
185 | major = strtoul(argv[1], &tmp, 0); | |
186 | if (*tmp) { | |
187 | fprintf(stderr, errmsg, "major number", argv[1]); | |
188 | exit(1); | |
189 | } | |
190 | minor = strtoul(argv[2], &tmp, 0); | |
191 | if (*tmp) { | |
192 | fprintf(stderr, errmsg, "minor number", argv[2]); | |
193 | exit(1); | |
194 | } | |
195 | device = makedev(major, minor); | |
196 | printf("Looking for device 0x%04x (%d:%d)\n", device, | |
197 | major, minor); | |
198 | } | |
199 | devname = ext2fs_find_block_device(device); | |
200 | if (devname) { | |
201 | printf("Found device! %s\n", devname); | |
202 | free(devname); | |
203 | } else { | |
204 | printf("Couldn't find device.\n"); | |
205 | } | |
206 | return 0; | |
207 | } | |
efc6f628 | 208 | |
de23aa1d | 209 | #endif |