diff options
Diffstat (limited to 'fs/isofs/dir.c')
-rw-r--r-- | fs/isofs/dir.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/fs/isofs/dir.c b/fs/isofs/dir.c new file mode 100644 index 0000000..14d86de --- /dev/null +++ b/fs/isofs/dir.c @@ -0,0 +1,280 @@ +/* + * 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; +} |