xref: /minix3/minix/lib/libvtreefs/link.c (revision e985b929927b5932e3b68f4b50587d458900107a)
1 /* VTreeFS - link.c - by Alen Stojanov and David van Moolenbroek */
2 
3 #include "inc.h"
4 
5 /*===========================================================================*
6  *				fs_rdlink				     *
7  *===========================================================================*/
8 ssize_t fs_rdlink(ino_t ino_nr, struct fsdriver_data *data, size_t bytes)
9 {
10 	/* Retrieve symbolic link target.
11 	 */
12 	char path[PATH_MAX];
13 	struct inode *node;
14 	size_t len;
15 	int r;
16 
17 	if ((node = find_inode(ino_nr)) == NULL)
18 		return EINVAL;
19 
20 	/* Call the rdlink hook. */
21 	assert(vtreefs_hooks->rdlink_hook != NULL);
22 	assert(!is_inode_deleted(node));	/* symlinks cannot be opened */
23 
24 	r = vtreefs_hooks->rdlink_hook(node, path, sizeof(path),
25 		get_inode_cbdata(node));
26 	if (r != OK) return r;
27 
28 	len = strlen(path);
29 	assert(len > 0 && len < sizeof(path));
30 
31 	if (len > bytes)
32 		len = bytes;
33 
34 	/* Copy out the result. */
35 	if ((r = fsdriver_copyout(data, 0, path, len)) != OK)
36 		return r;
37 
38 	return len;
39 }
40