]>
Commit | Line | Data |
---|---|---|
4dddc2d4 JB |
1 | /* |
2 | * swaplabel.c - Print or change the label / UUID of a swap partition | |
3 | * | |
4 | * Copyright (C) 2010 Jason Borden <jborden@bluehost.com> | |
5 | * Copyright (C) 2010 Karel Zak <kzak@redhat.com> | |
6 | * | |
7 | * Usage: swaplabel [-L label] [-U UUID] device | |
8 | * | |
9 | * This file may be redistributed under the terms of the GNU Public License | |
10 | * version 2 or later. | |
11 | * | |
12 | */ | |
13 | #include <stdio.h> | |
14 | #include <stddef.h> | |
15 | #include <string.h> | |
16 | #include <fcntl.h> | |
17 | #include <sys/types.h> | |
18 | #include <sys/stat.h> | |
19 | #include <unistd.h> | |
20 | #include <stdlib.h> | |
4dddc2d4 JB |
21 | #include <blkid.h> |
22 | #include <getopt.h> | |
23 | ||
24 | #ifdef HAVE_LIBUUID | |
25 | # ifdef HAVE_UUID_UUID_H | |
26 | # include <uuid/uuid.h> | |
27 | # else | |
28 | # include <uuid.h> | |
29 | # endif | |
30 | #endif | |
31 | ||
32 | #include "c.h" | |
33 | #include "writeall.h" | |
34 | #include "swapheader.h" | |
8abcf290 | 35 | #include "strutils.h" |
4dddc2d4 JB |
36 | #include "nls.h" |
37 | ||
38 | #define SWAP_UUID_OFFSET (offsetof(struct swap_header_v1_2, uuid)) | |
39 | #define SWAP_LABEL_OFFSET (offsetof(struct swap_header_v1_2, volume_name)) | |
40 | ||
41 | /* | |
42 | * Returns new libblkid prober. This function call exit() on error. | |
43 | */ | |
44 | static blkid_probe get_swap_prober(const char *devname) | |
45 | { | |
46 | blkid_probe pr; | |
47 | int rc; | |
48 | const char *version = NULL; | |
49 | char *swap_filter[] = { "swap", NULL }; | |
50 | ||
51 | pr = blkid_new_probe_from_filename(devname); | |
52 | if (!pr) { | |
53 | warn(_("%s: unable to probe device"), devname); | |
54 | return NULL; | |
55 | } | |
56 | ||
57 | blkid_probe_enable_superblocks(pr, TRUE); | |
58 | blkid_probe_set_superblocks_flags(pr, | |
59 | BLKID_SUBLKS_LABEL | BLKID_SUBLKS_UUID | | |
60 | BLKID_SUBLKS_VERSION); | |
61 | ||
62 | blkid_probe_filter_superblocks_type(pr, BLKID_FLTR_ONLYIN, swap_filter); | |
63 | ||
64 | rc = blkid_do_safeprobe(pr); | |
65 | if (rc == -1) | |
66 | warn(_("%s: unable to probe device"), devname); | |
67 | else if (rc == -2) | |
68 | warnx(_("%s: ambivalent probing result, use wipefs(8)"), devname); | |
69 | else if (rc == 1) | |
70 | warnx(_("%s: not a valid swap partition"), devname); | |
71 | ||
72 | if (rc == 0) { | |
73 | /* supported is SWAPSPACE2 only */ | |
74 | blkid_probe_lookup_value(pr, "VERSION", &version, NULL); | |
75 | if (strcmp(version, "2")) | |
76 | warnx(_("%s: unsupported swap version '%s'"), | |
77 | devname, version); | |
78 | else | |
79 | return pr; | |
80 | } | |
81 | ||
82 | blkid_free_probe(pr); | |
83 | return NULL; | |
84 | } | |
85 | ||
86 | /* Print the swap partition information */ | |
87 | static int print_info(blkid_probe pr, const char *devname) | |
88 | { | |
89 | const char *data; | |
90 | ||
91 | if (!blkid_probe_lookup_value(pr, "LABEL", &data, NULL)) | |
92 | printf("LABEL: %s\n", data); | |
93 | ||
94 | if (!blkid_probe_lookup_value(pr, "UUID", &data, NULL)) | |
95 | printf("UUID: %s\n", data); | |
96 | ||
97 | return 0; | |
98 | } | |
99 | ||
100 | /* Change the swap partition info */ | |
101 | static int change_info(const char *devname, const char *label, const char *uuid) | |
102 | { | |
103 | int fd; | |
104 | ||
105 | fd = open(devname, O_RDWR); | |
106 | if (fd < 0) { | |
107 | warn(_("%s: failed to open"), devname); | |
108 | goto err; | |
109 | } | |
110 | #ifdef HAVE_LIBUUID | |
111 | /* Write the uuid if it was provided */ | |
112 | if (uuid) { | |
113 | uuid_t newuuid; | |
114 | ||
115 | if (uuid_parse(uuid, newuuid) == -1) | |
116 | warnx(_("failed to parse UUID: %s"), uuid); | |
117 | else { | |
118 | if (lseek(fd, SWAP_UUID_OFFSET, SEEK_SET) != | |
119 | SWAP_UUID_OFFSET) { | |
120 | warn(_("%s: failed to seek to swap UUID"), devname); | |
121 | goto err; | |
122 | ||
123 | } else if (write_all(fd, newuuid, sizeof(newuuid))) { | |
124 | warn(_("%s: failed to write UUID"), devname); | |
125 | goto err; | |
126 | } | |
127 | } | |
128 | } | |
129 | #endif | |
130 | /* Write the label if it was provided */ | |
131 | if (label) { | |
132 | char newlabel[SWAP_LABEL_LENGTH]; | |
133 | ||
134 | if (lseek(fd, SWAP_LABEL_OFFSET, SEEK_SET) != SWAP_LABEL_OFFSET) { | |
135 | warn(_("%s: failed to seek to swap label "), devname); | |
136 | goto err; | |
137 | } | |
138 | memset(newlabel, 0, sizeof(newlabel)); | |
139 | xstrncpy(newlabel, label, sizeof(newlabel)); | |
140 | ||
141 | if (strlen(label) > strlen(newlabel)) | |
142 | warnx(_("label is too long. Truncating it to '%s'"), | |
143 | newlabel); | |
144 | if (write_all(fd, newlabel, sizeof(newlabel))) { | |
145 | warn(_("%s: failed to write label"), devname); | |
146 | goto err; | |
147 | } | |
148 | } | |
149 | ||
150 | close(fd); | |
151 | return 0; | |
152 | err: | |
153 | if (fd >= 0) | |
154 | close(fd); | |
155 | return -1; | |
156 | } | |
157 | ||
158 | static void __attribute__((__noreturn__)) usage(FILE *out) | |
159 | { | |
160 | fprintf(out, _("Usage: %s [options] <device>\n\nOptions:\n"), | |
161 | program_invocation_short_name); | |
162 | ||
163 | fprintf(out, _( | |
164 | " -h, --help this help\n" | |
165 | " -L, --label <label> specify a new label\n" | |
166 | " -U, --uuid <uuid> specify a new uuid\n")); | |
167 | ||
168 | fprintf(out, _("\nFor more information see swaplabel(8).\n")); | |
169 | ||
170 | exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS); | |
171 | } | |
172 | ||
173 | int main(int argc, char *argv[]) | |
174 | { | |
175 | blkid_probe pr = NULL; | |
176 | char *uuid = NULL, *label = NULL, *devname; | |
177 | int c, rc = -1; | |
178 | ||
179 | struct option longopts[] = { | |
180 | { "help", 0, 0, 'h' }, | |
181 | { "label", 1, 0, 'L' }, | |
182 | { "uuid", 1, 0, 'U' }, | |
183 | { NULL, 0, 0, 0 } | |
184 | }; | |
185 | ||
186 | setlocale(LC_ALL, ""); | |
187 | bindtextdomain(PACKAGE, LOCALEDIR); | |
188 | textdomain(PACKAGE); | |
189 | ||
190 | while ((c = getopt_long(argc, argv, "hL:U:", longopts, NULL)) != -1) { | |
191 | switch (c) { | |
192 | case 'h': | |
193 | usage(stdout); | |
194 | break; | |
195 | case 'L': | |
196 | label = optarg; | |
197 | break; | |
198 | case 'U': | |
199 | #ifdef HAVE_LIBUUID | |
200 | uuid = optarg; | |
201 | #else | |
202 | warnx(_("ignore -U (UUIDs are unsupported)")); | |
203 | #endif | |
204 | break; | |
205 | default: | |
206 | usage(stderr); | |
207 | break; | |
208 | } | |
209 | } | |
210 | ||
211 | if (optind == argc) | |
212 | usage(stderr); | |
213 | ||
214 | devname = argv[optind]; | |
215 | pr = get_swap_prober(devname); | |
216 | if (pr) { | |
217 | if (uuid || label) | |
218 | rc = change_info(devname, label, uuid); | |
219 | else | |
220 | rc = print_info(pr, devname); | |
221 | blkid_free_probe(pr); | |
222 | } | |
223 | return rc ? EXIT_FAILURE : EXIT_SUCCESS; | |
224 | } | |
225 |