remove pointers to the defunct UDF mailing list
[linux-2.6.git] / fs / udf / symlink.c
1 /*
2  * symlink.c
3  *
4  * PURPOSE
5  *      Symlink handling routines for the OSTA-UDF(tm) filesystem.
6  *
7  * COPYRIGHT
8  *      This file is distributed under the terms of the GNU General Public
9  *      License (GPL). Copies of the GPL can be obtained from:
10  *              ftp://prep.ai.mit.edu/pub/gnu/GPL
11  *      Each contributing author retains all rights to their own work.
12  *
13  *  (C) 1998-2001 Ben Fennema
14  *  (C) 1999 Stelias Computing Inc 
15  *
16  * HISTORY
17  *
18  *  04/16/99 blf  Created.
19  *
20  */
21
22 #include "udfdecl.h"
23 #include <asm/uaccess.h>
24 #include <linux/errno.h>
25 #include <linux/fs.h>
26 #include <linux/udf_fs.h>
27 #include <linux/time.h>
28 #include <linux/mm.h>
29 #include <linux/stat.h>
30 #include <linux/slab.h>
31 #include <linux/pagemap.h>
32 #include <linux/smp_lock.h>
33 #include <linux/buffer_head.h>
34 #include "udf_i.h"
35
36 static void udf_pc_to_char(struct super_block *sb, char *from, int fromlen, char *to)
37 {
38         struct pathComponent *pc;
39         int elen = 0;
40         char *p = to;
41
42         while (elen < fromlen)
43         {
44                 pc = (struct pathComponent *)(from + elen);
45                 switch (pc->componentType)
46                 {
47                         case 1:
48                                 if (pc->lengthComponentIdent == 0)
49                                 {
50                                         p = to;
51                                         *p++ = '/';
52                                 }
53                                 break;
54                         case 3:
55                                 memcpy(p, "../", 3);
56                                 p += 3;
57                                 break;
58                         case 4:
59                                 memcpy(p, "./", 2);
60                                 p += 2;
61                                 /* that would be . - just ignore */
62                                 break;
63                         case 5:
64                                 p += udf_get_filename(sb, pc->componentIdent, p, pc->lengthComponentIdent);
65                                 *p++ = '/';
66                                 break;
67                 }
68                 elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
69         }
70         if (p > to+1)
71                 p[-1] = '\0';
72         else
73                 p[0] = '\0';
74 }
75
76 static int udf_symlink_filler(struct file *file, struct page *page)
77 {
78         struct inode *inode = page->mapping->host;
79         struct buffer_head *bh = NULL;
80         char *symlink;
81         int err = -EIO;
82         char *p = kmap(page);
83
84         lock_kernel();
85         if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB)
86                 symlink = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
87         else
88         {
89                 bh = sb_bread(inode->i_sb, udf_block_map(inode, 0));
90
91                 if (!bh)
92                         goto out;
93
94                 symlink = bh->b_data;
95         }
96
97         udf_pc_to_char(inode->i_sb, symlink, inode->i_size, p);
98         udf_release_data(bh);
99
100         unlock_kernel();
101         SetPageUptodate(page);
102         kunmap(page);
103         unlock_page(page);
104         return 0;
105 out:
106         unlock_kernel();
107         SetPageError(page);
108         kunmap(page);
109         unlock_page(page);
110         return err;
111 }
112
113 /*
114  * symlinks can't do much...
115  */
116 struct address_space_operations udf_symlink_aops = {
117         .readpage               = udf_symlink_filler,
118 };