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-rw-r--r--fs/udf/symlink.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/fs/udf/symlink.c b/fs/udf/symlink.c
new file mode 100644
index 000000000000..43f3051ef756
--- /dev/null
+++ b/fs/udf/symlink.c
@@ -0,0 +1,123 @@
+/*
+ * symlink.c
+ *
+ * PURPOSE
+ * Symlink handling routines for the OSTA-UDF(tm) filesystem.
+ *
+ * CONTACTS
+ * E-mail regarding any portion of the Linux UDF file system should be
+ * directed to the development team mailing list (run by majordomo):
+ * linux_udf@hpesjro.fc.hp.com
+ *
+ * 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/udf_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);
+
+ lock_kernel();
+ if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB)
+ symlink = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
+ 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);
+ udf_release_data(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...
+ */
+struct address_space_operations udf_symlink_aops = {
+ .readpage = udf_symlink_filler,
+};