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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 | /* * linux/fs/isofs/dir.c * * (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO9660 filesystem. * * (C) 1991 Linus Torvalds - minix filesystem * * isofs directory handling functions */ #ifdef MODULE #include <linux/module.h> #endif #include <linux/errno.h> #include <asm/segment.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/malloc.h> #include <linux/sched.h> #include <linux/locks.h> static int isofs_readdir(struct inode *, struct file *, void *, filldir_t); static struct file_operations isofs_dir_operations = { NULL, /* lseek - default */ NULL, /* read */ NULL, /* write - bad */ isofs_readdir, /* readdir */ NULL, /* select - default */ NULL, /* ioctl - default */ NULL, /* no special open code */ NULL, /* no special release code */ NULL /* fsync */ }; /* * directories can handle most operations... */ struct inode_operations isofs_dir_inode_operations = { &isofs_dir_operations, /* default directory file-ops */ NULL, /* create */ isofs_lookup, /* lookup */ NULL, /* link */ NULL, /* unlink */ NULL, /* symlink */ NULL, /* mkdir */ NULL, /* rmdir */ NULL, /* mknod */ NULL, /* rename */ NULL, /* readlink */ NULL, /* follow_link */ isofs_bmap, /* bmap */ NULL, /* truncate */ NULL /* permission */ }; static int parent_inode_number(struct inode * inode, struct iso_directory_record * de) { int inode_number = inode->i_ino; if ((inode->i_sb->u.isofs_sb.s_firstdatazone) != inode->i_ino) inode_number = inode->u.isofs_i.i_backlink; if (inode_number != -1) return inode_number; /* This should never happen, but who knows. Try to be forgiving */ return isofs_lookup_grandparent(inode, find_rock_ridge_relocation(de, inode)); } static int isofs_name_translate(char * old, int len, char * new) { int i, c; for (i = 0; i < len; i++) { c = old[i]; if (!c) break; if (c >= 'A' && c <= 'Z') c |= 0x20; /* lower case */ /* Drop trailing '.;1' (ISO9660:1988 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 '.' */ if (c == ';') c = '.'; new[i] = c; } return i; } /* * 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 int block, offset; int inode_number; struct buffer_head *bh; int len, rrflag; int high_sierra = 0; char *name; struct iso_directory_record *de; offset = filp->f_pos & (bufsize - 1); block = isofs_bmap(inode, filp->f_pos >> bufbits); if (!block) return 0; if (!(bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size))) return 0; while (filp->f_pos < inode->i_size) { int de_len, next_offset; #ifdef DEBUG printk("Block, offset, f_pos: %x %x %x\n", block, offset, filp->f_pos); #endif /* Next directory_record on next CDROM sector */ if (offset >= bufsize) { brelse(bh); offset = 0; block = isofs_bmap(inode, (filp->f_pos) >> bufbits); if (!block) return 0; bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size); if (!bh) return 0; continue; } de = (struct iso_directory_record *) (bh->b_data + offset); inode_number = (block << bufbits) + (offset & (bufsize - 1)); 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); filp->f_pos = ((filp->f_pos & ~(ISOFS_BLOCK_SIZE - 1)) + ISOFS_BLOCK_SIZE); offset = 0; block = isofs_bmap(inode, (filp->f_pos) >> bufbits); if (!block) return 0; bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size); if (!bh) return 0; continue; } /* Make sure that the entire directory record is in the current bh block. If not, put the two halves together in "tmpde" */ next_offset = offset + de_len; if (next_offset > bufsize) { next_offset &= (bufsize - 1); memcpy(tmpde, de, bufsize - offset); brelse(bh); block = isofs_bmap(inode, (filp->f_pos + de_len) >> bufbits); if (!block) return 0; bh = breada(inode->i_dev, block, bufsize, filp->f_pos+de_len, inode->i_size); if (!bh) return 0; memcpy(bufsize - offset + (char *) tmpde, bh->b_data, next_offset); de = tmpde; } offset = next_offset; /* 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) < 0) break; filp->f_pos += de_len; continue; } /* Handle the case of the '..' directory */ if (de->name_len[0] == 1 && de->name[0] == 1) { inode_number = parent_inode_number(inode, de); if (inode_number == -1) break; if (filldir(dirent, "..", 2, filp->f_pos, inode_number) < 0) break; filp->f_pos += de_len; continue; } /* Handle everything else. Do name translation if there is no Rock Ridge NM field. */ if (inode->i_sb->u.isofs_sb.s_unhide == 'n') { /* Do not report hidden or associated files */ high_sierra = inode->i_sb->u.isofs_sb.s_high_sierra; if (de->flags[-high_sierra] & 5) { filp->f_pos += de_len; continue; } } /* Check Rock Ridge name translation.. */ len = de->name_len[0]; name = de->name; rrflag = get_rock_ridge_filename(de, &name, &len, inode); if (rrflag) { /* rrflag == 1 means that we have a new name (kmalloced) */ if (rrflag == 1) { rrflag = filldir(dirent, name, len, filp->f_pos, inode_number); dcache_add(inode, name, len, inode_number); kfree(name); /* this was allocated in get_r_r_filename.. */ if (rrflag < 0) break; } filp->f_pos += de_len; continue; } if (inode->i_sb->u.isofs_sb.s_mapping == 'n') { len = isofs_name_translate(name, len, tmpname); if (filldir(dirent, tmpname, len, filp->f_pos, inode_number) < 0) break; dcache_add(inode, tmpname, len, inode_number); filp->f_pos += de_len; continue; } if (filldir(dirent, name, len, filp->f_pos, inode_number) < 0) break; dcache_add(inode, name, len, inode_number); filp->f_pos += de_len; continue; } 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 inode *inode, struct file *filp, void *dirent, filldir_t filldir) { int result; char * tmpname; struct iso_directory_record * tmpde; if (!inode || !S_ISDIR(inode->i_mode)) return -EBADF; tmpname = (char *) __get_free_page(GFP_KERNEL); if (!tmpname) return -ENOMEM; tmpde = (struct iso_directory_record *) (tmpname+256); result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde); free_page((unsigned long) tmpname); return result; } |