diff options
Diffstat (limited to 'fs/udf/symlink.c')
-rw-r--r-- | fs/udf/symlink.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/fs/udf/symlink.c b/fs/udf/symlink.c new file mode 100644 index 0000000..c3265e1 --- /dev/null +++ b/fs/udf/symlink.c @@ -0,0 +1,118 @@ +/* + * symlink.c + * + * PURPOSE + * Symlink handling routines for the OSTA-UDF(tm) filesystem. + * + * COPYRIGHT + * This file is distributed under the terms of the GNU General Public + * License (GPL). Copies of the GPL can be obtained from: + * ftp://prep.ai.mit.edu/pub/gnu/GPL + * Each contributing author retains all rights to their own work. + * + * (C) 1998-2001 Ben Fennema + * (C) 1999 Stelias Computing Inc + * + * HISTORY + * + * 04/16/99 blf Created. + * + */ + +#include "udfdecl.h" +#include <asm/uaccess.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/time.h> +#include <linux/mm.h> +#include <linux/stat.h> +#include <linux/slab.h> +#include <linux/pagemap.h> +#include <linux/smp_lock.h> +#include <linux/buffer_head.h> +#include "udf_i.h" + +static void udf_pc_to_char(struct super_block *sb, char *from, int fromlen, + char *to) +{ + struct pathComponent *pc; + int elen = 0; + char *p = to; + + while (elen < fromlen) { + pc = (struct pathComponent *)(from + elen); + switch (pc->componentType) { + case 1: + if (pc->lengthComponentIdent == 0) { + p = to; + *p++ = '/'; + } + break; + case 3: + memcpy(p, "../", 3); + p += 3; + break; + case 4: + memcpy(p, "./", 2); + p += 2; + /* that would be . - just ignore */ + break; + case 5: + p += udf_get_filename(sb, pc->componentIdent, p, + pc->lengthComponentIdent); + *p++ = '/'; + break; + } + elen += sizeof(struct pathComponent) + pc->lengthComponentIdent; + } + if (p > to + 1) + p[-1] = '\0'; + else + p[0] = '\0'; +} + +static int udf_symlink_filler(struct file *file, struct page *page) +{ + struct inode *inode = page->mapping->host; + struct buffer_head *bh = NULL; + char *symlink; + int err = -EIO; + char *p = kmap(page); + struct udf_inode_info *iinfo; + + lock_kernel(); + iinfo = UDF_I(inode); + if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { + symlink = iinfo->i_ext.i_data + iinfo->i_lenEAttr; + } else { + bh = sb_bread(inode->i_sb, udf_block_map(inode, 0)); + + if (!bh) + goto out; + + symlink = bh->b_data; + } + + udf_pc_to_char(inode->i_sb, symlink, inode->i_size, p); + brelse(bh); + + unlock_kernel(); + SetPageUptodate(page); + kunmap(page); + unlock_page(page); + return 0; + +out: + unlock_kernel(); + SetPageError(page); + kunmap(page); + unlock_page(page); + return err; +} + +/* + * symlinks can't do much... + */ +const struct address_space_operations udf_symlink_aops = { + .readpage = udf_symlink_filler, +}; |