Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/isofs/dir.c | |
3 | * | |
4 | * (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO 9660 filesystem. | |
5 | * | |
6 | * (C) 1991 Linus Torvalds - minix filesystem | |
7 | * | |
8 | * Steve Beynon : Missing last directory entries fixed | |
9 | * (stephen@askone.demon.co.uk) : 21st June 1996 | |
10 | * | |
11 | * isofs directory handling functions | |
12 | */ | |
13 | #include <linux/errno.h> | |
14 | #include <linux/fs.h> | |
15 | #include <linux/iso_fs.h> | |
16 | #include <linux/kernel.h> | |
17 | #include <linux/stat.h> | |
18 | #include <linux/string.h> | |
19 | #include <linux/mm.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/time.h> | |
22 | #include <linux/config.h> | |
23 | #include <linux/smp_lock.h> | |
24 | #include <linux/buffer_head.h> | |
25 | ||
26 | #include <asm/uaccess.h> | |
27 | ||
28 | static int isofs_readdir(struct file *, void *, filldir_t); | |
29 | ||
30 | struct file_operations isofs_dir_operations = | |
31 | { | |
32 | .read = generic_read_dir, | |
33 | .readdir = isofs_readdir, | |
34 | }; | |
35 | ||
36 | /* | |
37 | * directories can handle most operations... | |
38 | */ | |
39 | struct inode_operations isofs_dir_inode_operations = | |
40 | { | |
41 | .lookup = isofs_lookup, | |
42 | }; | |
43 | ||
44 | int isofs_name_translate(struct iso_directory_record *de, char *new, struct inode *inode) | |
45 | { | |
46 | char * old = de->name; | |
47 | int len = de->name_len[0]; | |
48 | int i; | |
49 | ||
50 | for (i = 0; i < len; i++) { | |
51 | unsigned char c = old[i]; | |
52 | if (!c) | |
53 | break; | |
54 | ||
55 | if (c >= 'A' && c <= 'Z') | |
56 | c |= 0x20; /* lower case */ | |
57 | ||
58 | /* Drop trailing '.;1' (ISO 9660:1988 7.5.1 requires period) */ | |
59 | if (c == '.' && i == len - 3 && old[i + 1] == ';' && old[i + 2] == '1') | |
60 | break; | |
61 | ||
62 | /* Drop trailing ';1' */ | |
63 | if (c == ';' && i == len - 2 && old[i + 1] == '1') | |
64 | break; | |
65 | ||
66 | /* Convert remaining ';' to '.' */ | |
67 | /* Also '/' to '.' (broken Acorn-generated ISO9660 images) */ | |
68 | if (c == ';' || c == '/') | |
69 | c = '.'; | |
70 | ||
71 | new[i] = c; | |
72 | } | |
73 | return i; | |
74 | } | |
75 | ||
76 | /* Acorn extensions written by Matthew Wilcox <willy@bofh.ai> 1998 */ | |
77 | int get_acorn_filename(struct iso_directory_record * de, | |
78 | char * retname, struct inode * inode) | |
79 | { | |
80 | int std; | |
81 | unsigned char * chr; | |
82 | int retnamlen = isofs_name_translate(de, retname, inode); | |
83 | if (retnamlen == 0) return 0; | |
84 | std = sizeof(struct iso_directory_record) + de->name_len[0]; | |
85 | if (std & 1) std++; | |
86 | if ((*((unsigned char *) de) - std) != 32) return retnamlen; | |
87 | chr = ((unsigned char *) de) + std; | |
88 | if (strncmp(chr, "ARCHIMEDES", 10)) return retnamlen; | |
89 | if ((*retname == '_') && ((chr[19] & 1) == 1)) *retname = '!'; | |
90 | if (((de->flags[0] & 2) == 0) && (chr[13] == 0xff) | |
91 | && ((chr[12] & 0xf0) == 0xf0)) | |
92 | { | |
93 | retname[retnamlen] = ','; | |
94 | sprintf(retname+retnamlen+1, "%3.3x", | |
95 | ((chr[12] & 0xf) << 8) | chr[11]); | |
96 | retnamlen += 4; | |
97 | } | |
98 | return retnamlen; | |
99 | } | |
100 | ||
101 | /* | |
102 | * This should _really_ be cleaned up some day.. | |
103 | */ | |
104 | static int do_isofs_readdir(struct inode *inode, struct file *filp, | |
105 | void *dirent, filldir_t filldir, | |
106 | char * tmpname, struct iso_directory_record * tmpde) | |
107 | { | |
108 | unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); | |
109 | unsigned char bufbits = ISOFS_BUFFER_BITS(inode); | |
110 | unsigned long block, offset, block_saved, offset_saved; | |
111 | unsigned long inode_number = 0; /* Quiet GCC */ | |
112 | struct buffer_head *bh = NULL; | |
113 | int len; | |
114 | int map; | |
115 | int first_de = 1; | |
116 | char *p = NULL; /* Quiet GCC */ | |
117 | struct iso_directory_record *de; | |
118 | struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); | |
119 | ||
120 | offset = filp->f_pos & (bufsize - 1); | |
121 | block = filp->f_pos >> bufbits; | |
122 | ||
123 | while (filp->f_pos < inode->i_size) { | |
124 | int de_len; | |
125 | ||
126 | if (!bh) { | |
127 | bh = isofs_bread(inode, block); | |
128 | if (!bh) | |
129 | return 0; | |
130 | } | |
131 | ||
132 | de = (struct iso_directory_record *) (bh->b_data + offset); | |
133 | ||
134 | de_len = *(unsigned char *) de; | |
135 | ||
136 | /* If the length byte is zero, we should move on to the next | |
137 | CDROM sector. If we are at the end of the directory, we | |
138 | kick out of the while loop. */ | |
139 | ||
140 | if (de_len == 0) { | |
141 | brelse(bh); | |
142 | bh = NULL; | |
143 | filp->f_pos = (filp->f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1); | |
144 | block = filp->f_pos >> bufbits; | |
145 | offset = 0; | |
146 | continue; | |
147 | } | |
148 | ||
149 | block_saved = block; | |
150 | offset_saved = offset; | |
151 | offset += de_len; | |
152 | ||
153 | /* Make sure we have a full directory entry */ | |
154 | if (offset >= bufsize) { | |
155 | int slop = bufsize - offset + de_len; | |
156 | memcpy(tmpde, de, slop); | |
157 | offset &= bufsize - 1; | |
158 | block++; | |
159 | brelse(bh); | |
160 | bh = NULL; | |
161 | if (offset) { | |
162 | bh = isofs_bread(inode, block); | |
163 | if (!bh) | |
164 | return 0; | |
165 | memcpy((void *) tmpde + slop, bh->b_data, offset); | |
166 | } | |
167 | de = tmpde; | |
168 | } | |
169 | ||
170 | if (first_de) { | |
171 | isofs_normalize_block_and_offset(de, | |
172 | &block_saved, | |
173 | &offset_saved); | |
174 | inode_number = isofs_get_ino(block_saved, | |
175 | offset_saved, | |
176 | bufbits); | |
177 | } | |
178 | ||
179 | if (de->flags[-sbi->s_high_sierra] & 0x80) { | |
180 | first_de = 0; | |
181 | filp->f_pos += de_len; | |
182 | continue; | |
183 | } | |
184 | first_de = 1; | |
185 | ||
186 | /* Handle the case of the '.' directory */ | |
187 | if (de->name_len[0] == 1 && de->name[0] == 0) { | |
188 | if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0) | |
189 | break; | |
190 | filp->f_pos += de_len; | |
191 | continue; | |
192 | } | |
193 | ||
194 | len = 0; | |
195 | ||
196 | /* Handle the case of the '..' directory */ | |
197 | if (de->name_len[0] == 1 && de->name[0] == 1) { | |
198 | inode_number = parent_ino(filp->f_dentry); | |
199 | if (filldir(dirent, "..", 2, filp->f_pos, inode_number, DT_DIR) < 0) | |
200 | break; | |
201 | filp->f_pos += de_len; | |
202 | continue; | |
203 | } | |
204 | ||
205 | /* Handle everything else. Do name translation if there | |
206 | is no Rock Ridge NM field. */ | |
207 | if (sbi->s_unhide == 'n') { | |
208 | /* Do not report hidden or associated files */ | |
209 | if (de->flags[-sbi->s_high_sierra] & 5) { | |
210 | filp->f_pos += de_len; | |
211 | continue; | |
212 | } | |
213 | } | |
214 | ||
215 | map = 1; | |
216 | if (sbi->s_rock) { | |
217 | len = get_rock_ridge_filename(de, tmpname, inode); | |
218 | if (len != 0) { /* may be -1 */ | |
219 | p = tmpname; | |
220 | map = 0; | |
221 | } | |
222 | } | |
223 | if (map) { | |
224 | #ifdef CONFIG_JOLIET | |
225 | if (sbi->s_joliet_level) { | |
226 | len = get_joliet_filename(de, tmpname, inode); | |
227 | p = tmpname; | |
228 | } else | |
229 | #endif | |
230 | if (sbi->s_mapping == 'a') { | |
231 | len = get_acorn_filename(de, tmpname, inode); | |
232 | p = tmpname; | |
233 | } else | |
234 | if (sbi->s_mapping == 'n') { | |
235 | len = isofs_name_translate(de, tmpname, inode); | |
236 | p = tmpname; | |
237 | } else { | |
238 | p = de->name; | |
239 | len = de->name_len[0]; | |
240 | } | |
241 | } | |
242 | if (len > 0) { | |
243 | if (filldir(dirent, p, len, filp->f_pos, inode_number, DT_UNKNOWN) < 0) | |
244 | break; | |
245 | } | |
246 | filp->f_pos += de_len; | |
247 | ||
248 | continue; | |
249 | } | |
250 | if (bh) brelse(bh); | |
251 | return 0; | |
252 | } | |
253 | ||
254 | /* | |
255 | * Handle allocation of temporary space for name translation and | |
256 | * handling split directory entries.. The real work is done by | |
257 | * "do_isofs_readdir()". | |
258 | */ | |
259 | static int isofs_readdir(struct file *filp, | |
260 | void *dirent, filldir_t filldir) | |
261 | { | |
262 | int result; | |
263 | char * tmpname; | |
264 | struct iso_directory_record * tmpde; | |
265 | struct inode *inode = filp->f_dentry->d_inode; | |
266 | ||
267 | ||
268 | tmpname = (char *)__get_free_page(GFP_KERNEL); | |
269 | if (tmpname == NULL) | |
270 | return -ENOMEM; | |
271 | ||
272 | lock_kernel(); | |
273 | tmpde = (struct iso_directory_record *) (tmpname+1024); | |
274 | ||
275 | result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde); | |
276 | ||
277 | free_page((unsigned long) tmpname); | |
278 | unlock_kernel(); | |
279 | return result; | |
280 | } |