1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24#include <common.h>
25#include <ext_common.h>
26#include <ext4fs.h>
27#include "ext4_common.h"
28#include <div64.h>
29
30int ext4fs_symlinknest;
31struct ext_filesystem ext_fs;
32
33struct ext_filesystem *get_fs(void)
34{
35 return &ext_fs;
36}
37
38void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
39{
40 if ((node != &ext4fs_root->diropen) && (node != currroot))
41 free(node);
42}
43
44
45
46
47
48
49int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
50 loff_t len, char *buf, loff_t *actread)
51{
52 struct ext_filesystem *fs = get_fs();
53 int i;
54 lbaint_t blockcnt;
55 int log2blksz = fs->dev_desc->log2blksz;
56 int log2_fs_blocksize = LOG2_BLOCK_SIZE(node->data) - log2blksz;
57 int blocksize = (1 << (log2_fs_blocksize + log2blksz));
58 unsigned int filesize = le32_to_cpu(node->inode.size);
59 lbaint_t previous_block_number = -1;
60 lbaint_t delayed_start = 0;
61 lbaint_t delayed_extent = 0;
62 lbaint_t delayed_skipfirst = 0;
63 lbaint_t delayed_next = 0;
64 char *delayed_buf = NULL;
65 short status;
66
67
68 if (len + pos > filesize)
69 len = (filesize - pos);
70
71 blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
72
73 for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
74 long int blknr;
75 int blockoff = pos - (blocksize * i);
76 int blockend = blocksize;
77 int skipfirst = 0;
78 blknr = read_allocated_block(&(node->inode), i);
79 if (blknr < 0)
80 return -1;
81
82 blknr = blknr << log2_fs_blocksize;
83
84
85 if (i == blockcnt - 1) {
86 blockend = (len + pos) - (blocksize * i);
87
88
89 if (!blockend)
90 blockend = blocksize;
91 }
92
93
94 if (i == lldiv(pos, blocksize)) {
95 skipfirst = blockoff;
96 blockend -= skipfirst;
97 }
98 if (blknr) {
99 int status;
100
101 if (previous_block_number != -1) {
102 if (delayed_next == blknr) {
103 delayed_extent += blockend;
104 delayed_next += blockend >> log2blksz;
105 } else {
106 status = ext4fs_devread(delayed_start,
107 delayed_skipfirst,
108 delayed_extent,
109 delayed_buf);
110 if (status == 0)
111 return -1;
112 previous_block_number = blknr;
113 delayed_start = blknr;
114 delayed_extent = blockend;
115 delayed_skipfirst = skipfirst;
116 delayed_buf = buf;
117 delayed_next = blknr +
118 (blockend >> log2blksz);
119 }
120 } else {
121 previous_block_number = blknr;
122 delayed_start = blknr;
123 delayed_extent = blockend;
124 delayed_skipfirst = skipfirst;
125 delayed_buf = buf;
126 delayed_next = blknr +
127 (blockend >> log2blksz);
128 }
129 } else {
130 if (previous_block_number != -1) {
131
132 status = ext4fs_devread(delayed_start,
133 delayed_skipfirst,
134 delayed_extent,
135 delayed_buf);
136 if (status == 0)
137 return -1;
138 previous_block_number = -1;
139 }
140 memset(buf, 0, blocksize - skipfirst);
141 }
142 buf += blocksize - skipfirst;
143 }
144 if (previous_block_number != -1) {
145
146 status = ext4fs_devread(delayed_start,
147 delayed_skipfirst, delayed_extent,
148 delayed_buf);
149 if (status == 0)
150 return -1;
151 previous_block_number = -1;
152 }
153
154 *actread = len;
155 return 0;
156}
157
158int ext4fs_ls(const char *dirname)
159{
160 struct ext2fs_node *dirnode;
161 int status;
162
163 if (dirname == NULL)
164 return 0;
165
166 status = ext4fs_find_file(dirname, &ext4fs_root->diropen, &dirnode,
167 FILETYPE_DIRECTORY);
168 if (status != 1) {
169 printf("** Can not find directory. **\n");
170 return 1;
171 }
172
173 ext4fs_iterate_dir(dirnode, NULL, NULL, NULL);
174 ext4fs_free_node(dirnode, &ext4fs_root->diropen);
175
176 return 0;
177}
178
179int ext4fs_exists(const char *filename)
180{
181 loff_t file_len;
182 int ret;
183
184 ret = ext4fs_open(filename, &file_len);
185 return ret == 0;
186}
187
188int ext4fs_size(const char *filename, loff_t *size)
189{
190 return ext4fs_open(filename, size);
191}
192
193int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
194{
195 if (ext4fs_root == NULL || ext4fs_file == NULL)
196 return -1;
197
198 return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
199}
200
201int ext4fs_probe(struct blk_desc *fs_dev_desc,
202 disk_partition_t *fs_partition)
203{
204 ext4fs_set_blk_dev(fs_dev_desc, fs_partition);
205
206 if (!ext4fs_mount(fs_partition->size)) {
207 ext4fs_close();
208 return -1;
209 }
210
211 return 0;
212}
213
214int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
215 loff_t *len_read)
216{
217 loff_t file_len;
218 int ret;
219
220 ret = ext4fs_open(filename, &file_len);
221 if (ret < 0) {
222 printf("** File not found %s **\n", filename);
223 return -1;
224 }
225
226 if (len == 0)
227 len = file_len;
228
229 return ext4fs_read(buf, offset, len, len_read);
230}
231
232int ext4fs_uuid(char *uuid_str)
233{
234 if (ext4fs_root == NULL)
235 return -1;
236
237#ifdef CONFIG_LIB_UUID
238 uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
239 uuid_str, UUID_STR_FORMAT_STD);
240
241 return 0;
242#else
243 return -ENOSYS;
244#endif
245}
246
