libblkid-tiny: use separated buffer for each block device read
[project/fstools.git] / libblkid-tiny / libblkid-tiny.c
1 #include <stdio.h>
2 #include <sys/utsname.h>
3
4 #include "libblkid-tiny.h"
5 #include "superblocks.h"
6 #include "linux_version.h"
7
8 #if 0
9 #define DEBUG(fmt, ...) printf(fmt, __VA_ARGS__)
10 #else
11 #define DEBUG(fmt, ...)
12 #endif
13
14 int blkid_debug_mask = 0;
15
16 int get_linux_version (void)
17 {
18 static int kver = -1;
19 struct utsname uts;
20 int major = 0;
21 int minor = 0;
22 int teeny = 0;
23 int n;
24
25 if (kver != -1)
26 return kver;
27 if (uname (&uts))
28 return kver = 0;
29
30 n = sscanf(uts.release, "%d.%d.%d", &major, &minor, &teeny);
31 if (n < 1 || n > 3)
32 return kver = 0;
33
34 return kver = KERNEL_VERSION(major, minor, teeny);
35 }
36
37 int blkid_probe_is_tiny(blkid_probe pr)
38 {
39 /* never true ? */
40 return 0;
41 }
42
43 int blkid_probe_set_value(blkid_probe pr, const char *name,
44 unsigned char *data, size_t len)
45 {
46 /* empty stub */
47 return 0;
48 }
49
50 int blkid_probe_set_version(blkid_probe pr, const char *version)
51 {
52 int len = strlen(version);
53 if (len > (sizeof(pr->version) - 1)) {
54 fprintf(stderr, "version buffer too small %d\n", len);
55 return -1;
56 }
57
58 strncpy(pr->version, version, sizeof(pr->version));
59
60 return 0;
61 }
62
63 int blkid_probe_sprintf_version(blkid_probe pr, const char *fmt, ...)
64 {
65 va_list ap;
66 int n;
67
68 va_start(ap, fmt);
69 n = vsnprintf(pr->version, sizeof(pr->version), fmt, ap);
70 va_end(ap);
71
72 if (n >= sizeof(pr->version))
73 fprintf(stderr, "version buffer too small %d\n", n);
74
75 return 0;
76 }
77
78 unsigned char *blkid_probe_get_buffer(blkid_probe pr,
79 blkid_loff_t off, blkid_loff_t len)
80 {
81 struct blkid_bufinfo *bf;
82 int ret;
83
84 bf = malloc(sizeof(*bf) + len);
85 if (!bf)
86 return NULL;
87 memset(bf, 0, sizeof(*bf));
88 bf->data = ((unsigned char *)bf) + sizeof(*bf);
89
90 lseek(pr->fd, off, SEEK_SET);
91 ret = read(pr->fd, bf->data, len);
92
93 if (ret != len) {
94 fprintf(stderr, "faile to read blkid\n");
95 free(bf);
96 return NULL;
97 }
98
99 list_add_tail(&bf->bufs, &pr->buffers);
100
101 return bf->data;
102 }
103
104 int blkid_probe_set_label(blkid_probe pr, unsigned char *label, size_t len)
105 {
106 if (len > (sizeof(pr->label) - 1)) {
107 fprintf(stderr, "label buffer too small %d > %d\n",
108 (int) len, (int) sizeof(pr->label) - 1);
109 return -1;
110 }
111 memcpy(pr->label, label, len + 1);
112
113 return 0;
114 }
115
116 int blkid_probe_set_utf8label(blkid_probe pr, unsigned char *label,
117 size_t len, int enc)
118 {
119 if (len > (sizeof(pr->label) - 1)) {
120 fprintf(stderr, "label buffer too small %d > %d\n",
121 (int) len, (int) sizeof(pr->label) - 1);
122 return -1;
123 }
124
125 blkid_encode_to_utf8(enc,(unsigned char*) pr->label, len,
126 label, len+1);
127
128 return 0;
129 }
130
131 int blkid_probe_set_uuid_as(blkid_probe pr, unsigned char *uuid, const char *name)
132 {
133 short unsigned int*u = (short unsigned int*) uuid;
134
135 if (u[0] && (!name || !strcmp(name, "UUID"))) {
136 sprintf(pr->uuid,
137 "%04x%04x-%04x-%04x-%04x-%04x%04x%04x",
138 be16_to_cpu(u[0]), be16_to_cpu(u[1]), be16_to_cpu(u[2]), be16_to_cpu(u[3]),
139 be16_to_cpu(u[4]), be16_to_cpu(u[5]), be16_to_cpu(u[6]), be16_to_cpu(u[7]));
140 }
141
142 return 0;
143 }
144
145 int blkid_probe_set_uuid(blkid_probe pr, unsigned char *uuid)
146 {
147 return blkid_probe_set_uuid_as(pr, uuid, NULL);
148 }
149
150 int blkid_probe_sprintf_uuid(blkid_probe pr, unsigned char *uuid,
151 size_t len, const char *fmt, ...)
152 {
153 va_list ap;
154
155 va_start(ap, fmt);
156 vsnprintf(pr->uuid, sizeof(pr->uuid), fmt, ap);
157 va_end(ap);
158
159 return 0;
160 }
161
162 static const struct blkid_idinfo *idinfos[] =
163 {
164 &vfat_idinfo,
165 &swsuspend_idinfo,
166 &swap_idinfo,
167 &ext4dev_idinfo,
168 &ext4_idinfo,
169 &ext3_idinfo,
170 &ext2_idinfo,
171 &jbd_idinfo,
172 &ntfs_idinfo,
173 &squashfs_idinfo,
174 &ubi_idinfo,
175 &ubifs_idinfo,
176 &jffs2_idinfo,
177 &hfsplus_idinfo,
178 &hfs_idinfo,
179 &btrfs_idinfo,
180 &f2fs_idinfo,
181 };
182
183 int probe_block(char *block, struct blkid_struct_probe *pr)
184 {
185 struct stat s;
186 int i;
187
188 if (stat(block, &s) || (!S_ISBLK(s.st_mode) && !S_ISREG(s.st_mode) && !strncmp(block, "ubi", 3)))
189 return -1;
190
191 pr->err = -1;
192 pr->fd = open(block, O_RDONLY);
193 if (!pr->fd)
194 return -1;
195
196 for (i = 0; i < ARRAY_SIZE(idinfos); i++) {
197 /* loop over all magic handlers */
198 const struct blkid_idmag *mag;
199
200 /* loop over all probe handlers */
201 DEBUG("scanning %s\n", idinfos[i]->name);
202
203 mag = &idinfos[i]->magics[0];
204
205 while (mag->magic) {
206 int off = (mag->kboff * 1024) + mag->sboff;
207 char magic[32] = { 0 };
208
209 lseek(pr->fd, off, SEEK_SET);
210 if (read(pr->fd, magic, mag->len) < 0)
211 return -1;
212
213 DEBUG("magic: %s %s %d\n", mag->magic, magic, mag->len);
214 if (!memcmp(mag->magic, magic, mag->len))
215 break;
216 mag++;
217 }
218
219 if (mag && mag->magic) {
220 DEBUG("probing %s\n", idinfos[i]->name);
221 pr->err = idinfos[i]->probefunc(pr, mag);
222 pr->id = idinfos[i];
223 strcpy(pr->dev, block);
224 if (!pr->err)
225 break;
226 }
227 }
228
229 close(pr->fd);
230
231 return 0;
232 }