1 /*
2 * Copyright (c) 2007 Travis Geiselbrecht
3 *
4 * Use of this source code is governed by a MIT-style
5 * license that can be found in the LICENSE file or at
6 * https://opensource.org/licenses/MIT
7 */
8
9 #include <stdlib.h>
10 #include <string.h>
11 #include <stdlib.h>
12 #include <lk/err.h>
13 #include <lk/debug.h>
14 #include <lk/trace.h>
15 #include "ext2_priv.h"
16
17 #define LOCAL_TRACE 0
18
ext2_open_file(fscookie * cookie,const char * path,filecookie ** fcookie)19 int ext2_open_file(fscookie *cookie, const char *path, filecookie **fcookie) {
20 ext2_t *ext2 = (ext2_t *)cookie;
21 int err;
22
23 /* do a path lookup */
24 inodenum_t inum;
25 err = ext2_lookup(ext2, path, &inum);
26 if (err < 0)
27 return err;
28
29 /* create the file object */
30 ext2_file_t *file = malloc(sizeof(ext2_file_t));
31 memset(file, 0, sizeof(ext2_file_t));
32
33 /* read in the inode */
34 err = ext2_load_inode(ext2, inum, &file->inode);
35 if (err < 0) {
36 free(file);
37 return err;
38 }
39
40 file->ext2 = ext2;
41 *fcookie = (filecookie *)file;
42
43 return 0;
44 }
45
ext2_read_file(filecookie * fcookie,void * buf,off_t offset,size_t len)46 ssize_t ext2_read_file(filecookie *fcookie, void *buf, off_t offset, size_t len) {
47 ext2_file_t *file = (ext2_file_t *)fcookie;
48 int err;
49
50 // test that it's a file
51 if (!S_ISREG(file->inode.i_mode)) {
52 dprintf(INFO, "ext2_read_file: not a file\n");
53 return -1;
54 }
55
56 // read from the inode
57 err = ext2_read_inode(file->ext2, &file->inode, buf, offset, len);
58
59 return err;
60 }
61
ext2_close_file(filecookie * fcookie)62 int ext2_close_file(filecookie *fcookie) {
63 ext2_file_t *file = (ext2_file_t *)fcookie;
64
65 // see if we need to free any of the cache blocks
66 int i;
67 for (i=0; i < 3; i++) {
68 if (file->ind_cache[i].num != 0) {
69 free(file->ind_cache[i].ptr);
70 }
71 }
72
73 free(file);
74
75 return 0;
76 }
77
ext2_file_len(ext2_t * ext2,struct ext2_inode * inode)78 off_t ext2_file_len(ext2_t *ext2, struct ext2_inode *inode) {
79 /* calculate the file size */
80 off_t len = inode->i_size;
81 if ((ext2->sb.s_feature_ro_compat & EXT2_FEATURE_RO_COMPAT_LARGE_FILE) && (S_ISREG(inode->i_mode))) {
82 /* can potentially be a large file */
83 len |= (off_t)inode->i_size_high << 32;
84 }
85
86 return len;
87 }
88
ext2_stat_file(filecookie * fcookie,struct file_stat * stat)89 int ext2_stat_file(filecookie *fcookie, struct file_stat *stat) {
90 ext2_file_t *file = (ext2_file_t *)fcookie;
91
92 stat->size = ext2_file_len(file->ext2, &file->inode);
93
94 /* is it a dir? */
95 stat->is_dir = false;
96 if (S_ISDIR(file->inode.i_mode))
97 stat->is_dir = true;
98
99 return 0;
100 }
101
ext2_read_link(ext2_t * ext2,struct ext2_inode * inode,char * str,size_t len)102 int ext2_read_link(ext2_t *ext2, struct ext2_inode *inode, char *str, size_t len) {
103 LTRACEF("inode %p, str %p, len %zu\n", inode, str, len);
104
105 off_t linklen = ext2_file_len(ext2, inode);
106
107 if ((linklen < 0) || (linklen + 1 > (off_t)len))
108 return ERR_NO_MEMORY;
109
110 if (linklen > 60) {
111 int err = ext2_read_inode(ext2, inode, str, 0, linklen);
112 if (err < 0)
113 return err;
114 str[linklen] = 0;
115 } else {
116 memcpy(str, &inode->i_block[0], linklen);
117 str[linklen] = 0;
118 }
119
120 LTRACEF("read link '%s'\n", str);
121
122 return linklen;
123 }
124
125