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23#include <common.h>
24#include <ext_common.h>
25#include <ext4fs.h>
26#include "ext4_common.h"
27#include <div64.h>
28
29int ext4fs_symlinknest;
30struct ext_filesystem ext_fs;
31
32struct ext_filesystem *get_fs(void)
33{
34 return &ext_fs;
35}
36
37void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
38{
39 if ((node != &ext4fs_root->diropen) && (node != currroot))
40 free(node);
41}
42
43
44
45
46
47
48int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
49 loff_t len, char *buf, loff_t *actread)
50{
51 struct ext_filesystem *fs = get_fs();
52 int i;
53 lbaint_t blockcnt;
54 int log2blksz = fs->dev_desc->log2blksz;
55 int log2_fs_blocksize = LOG2_BLOCK_SIZE(node->data) - log2blksz;
56 int blocksize = (1 << (log2_fs_blocksize + log2blksz));
57 unsigned int filesize = le32_to_cpu(node->inode.size);
58 lbaint_t previous_block_number = -1;
59 lbaint_t delayed_start = 0;
60 lbaint_t delayed_extent = 0;
61 lbaint_t delayed_skipfirst = 0;
62 lbaint_t delayed_next = 0;
63 char *delayed_buf = NULL;
64 short status;
65
66 if (blocksize <= 0)
67 return -1;
68
69
70 if (len + pos > filesize)
71 len = (filesize - pos);
72
73 blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
74
75 for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
76 long int blknr;
77 int blockoff = pos - (blocksize * i);
78 int blockend = blocksize;
79 int skipfirst = 0;
80 blknr = read_allocated_block(&(node->inode), i);
81 if (blknr < 0)
82 return -1;
83
84 blknr = blknr << log2_fs_blocksize;
85
86
87 if (i == blockcnt - 1) {
88 blockend = (len + pos) - (blocksize * i);
89
90
91 if (!blockend)
92 blockend = blocksize;
93 }
94
95
96 if (i == lldiv(pos, blocksize)) {
97 skipfirst = blockoff;
98 blockend -= skipfirst;
99 }
100 if (blknr) {
101 int status;
102
103 if (previous_block_number != -1) {
104 if (delayed_next == blknr) {
105 delayed_extent += blockend;
106 delayed_next += blockend >> log2blksz;
107 } else {
108 status = ext4fs_devread(delayed_start,
109 delayed_skipfirst,
110 delayed_extent,
111 delayed_buf);
112 if (status == 0)
113 return -1;
114 previous_block_number = blknr;
115 delayed_start = blknr;
116 delayed_extent = blockend;
117 delayed_skipfirst = skipfirst;
118 delayed_buf = buf;
119 delayed_next = blknr +
120 (blockend >> log2blksz);
121 }
122 } else {
123 previous_block_number = blknr;
124 delayed_start = blknr;
125 delayed_extent = blockend;
126 delayed_skipfirst = skipfirst;
127 delayed_buf = buf;
128 delayed_next = blknr +
129 (blockend >> log2blksz);
130 }
131 } else {
132 int n;
133 if (previous_block_number != -1) {
134
135 status = ext4fs_devread(delayed_start,
136 delayed_skipfirst,
137 delayed_extent,
138 delayed_buf);
139 if (status == 0)
140 return -1;
141 previous_block_number = -1;
142 }
143
144 n = blocksize - skipfirst;
145 if (n > len)
146 n = len;
147 memset(buf, 0, n);
148 }
149 buf += blocksize - skipfirst;
150 }
151 if (previous_block_number != -1) {
152
153 status = ext4fs_devread(delayed_start,
154 delayed_skipfirst, delayed_extent,
155 delayed_buf);
156 if (status == 0)
157 return -1;
158 previous_block_number = -1;
159 }
160
161 *actread = len;
162 return 0;
163}
164
165int ext4fs_ls(const char *dirname)
166{
167 struct ext2fs_node *dirnode = NULL;
168 int status;
169
170 if (dirname == NULL)
171 return 0;
172
173 status = ext4fs_find_file(dirname, &ext4fs_root->diropen, &dirnode,
174 FILETYPE_DIRECTORY);
175 if (status != 1) {
176 printf("** Can not find directory. **\n");
177 if (dirnode)
178 ext4fs_free_node(dirnode, &ext4fs_root->diropen);
179 return 1;
180 }
181
182 ext4fs_iterate_dir(dirnode, NULL, NULL, NULL);
183 ext4fs_free_node(dirnode, &ext4fs_root->diropen);
184
185 return 0;
186}
187
188int ext4fs_exists(const char *filename)
189{
190 loff_t file_len;
191 int ret;
192
193 ret = ext4fs_open(filename, &file_len);
194 return ret == 0;
195}
196
197int ext4fs_size(const char *filename, loff_t *size)
198{
199 return ext4fs_open(filename, size);
200}
201
202int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
203{
204 if (ext4fs_root == NULL || ext4fs_file == NULL)
205 return -1;
206
207 return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
208}
209
210int ext4fs_probe(struct blk_desc *fs_dev_desc,
211 disk_partition_t *fs_partition)
212{
213 ext4fs_set_blk_dev(fs_dev_desc, fs_partition);
214
215 if (!ext4fs_mount(fs_partition->size)) {
216 ext4fs_close();
217 return -1;
218 }
219
220 return 0;
221}
222
223int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
224 loff_t *len_read)
225{
226 loff_t file_len;
227 int ret;
228
229 ret = ext4fs_open(filename, &file_len);
230 if (ret < 0) {
231 printf("** File not found %s **\n", filename);
232 return -1;
233 }
234
235 if (len == 0)
236 len = file_len;
237
238 return ext4fs_read(buf, offset, len, len_read);
239}
240
241int ext4fs_uuid(char *uuid_str)
242{
243 if (ext4fs_root == NULL)
244 return -1;
245
246#ifdef CONFIG_LIB_UUID
247 uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
248 uuid_str, UUID_STR_FORMAT_STD);
249
250 return 0;
251#else
252 return -ENOSYS;
253#endif
254}
255