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