| /* |
| * 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/gfp.h> |
| #include "isofs.h" |
| |
| 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 *file, |
| struct dir_context *ctx, |
| 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 = ctx->pos & (bufsize - 1); |
| block = ctx->pos >> bufbits; |
| |
| while (ctx->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; |
| ctx->pos = (ctx->pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1); |
| block = ctx->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; |
| } |
| /* Basic sanity check, whether name doesn't exceed dir entry */ |
| if (de_len < de->name_len[0] + |
| sizeof(struct iso_directory_record)) { |
| printk(KERN_NOTICE "iso9660: Corrupted directory entry" |
| " in block %lu of inode %lu\n", block, |
| inode->i_ino); |
| return -EIO; |
| } |
| |
| 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; |
| ctx->pos += de_len; |
| continue; |
| } |
| first_de = 1; |
| |
| /* Handle the case of the '.' directory */ |
| if (de->name_len[0] == 1 && de->name[0] == 0) { |
| if (!dir_emit_dot(file, ctx)) |
| break; |
| ctx->pos += de_len; |
| continue; |
| } |
| |
| len = 0; |
| |
| /* Handle the case of the '..' directory */ |
| if (de->name_len[0] == 1 && de->name[0] == 1) { |
| if (!dir_emit_dotdot(file, ctx)) |
| break; |
| ctx->pos += de_len; |
| continue; |
| } |
| |
| /* Handle everything else. Do name translation if there |
| is no Rock Ridge NM field. */ |
| |
| /* |
| * Do not report hidden files if so instructed, or associated |
| * files unless instructed to do so |
| */ |
| if ((sbi->s_hide && (de->flags[-sbi->s_high_sierra] & 1)) || |
| (!sbi->s_showassoc && |
| (de->flags[-sbi->s_high_sierra] & 4))) { |
| ctx->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 (!dir_emit(ctx, p, len, inode_number, DT_UNKNOWN)) |
| break; |
| } |
| ctx->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 *file, struct dir_context *ctx) |
| { |
| int result; |
| char *tmpname; |
| struct iso_directory_record *tmpde; |
| struct inode *inode = file_inode(file); |
| |
| tmpname = (char *)__get_free_page(GFP_KERNEL); |
| if (tmpname == NULL) |
| return -ENOMEM; |
| |
| tmpde = (struct iso_directory_record *) (tmpname+1024); |
| |
| result = do_isofs_readdir(inode, file, ctx, tmpname, tmpde); |
| |
| free_page((unsigned long) tmpname); |
| return result; |
| } |
| |
| const struct file_operations isofs_dir_operations = |
| { |
| .llseek = generic_file_llseek, |
| .read = generic_read_dir, |
| .iterate = isofs_readdir, |
| }; |
| |
| /* |
| * directories can handle most operations... |
| */ |
| const struct inode_operations isofs_dir_inode_operations = |
| { |
| .lookup = isofs_lookup, |
| }; |
| |
| |