minix3/lib/libvtreefs/link.c

42 lines
1.1 KiB
C

/* VTreeFS - link.c - by Alen Stojanov and David van Moolenbroek */
#include "inc.h"
/*===========================================================================*
* fs_rdlink *
*===========================================================================*/
int fs_rdlink(void)
{
/* Retrieve symbolic link target.
*/
char path[PATH_MAX];
struct inode *node;
size_t len;
int r;
if ((node = find_inode(fs_m_in.m_vfs_fs_rdlink.inode)) == NULL)
return EINVAL;
/* Call the rdlink hook. */
assert(vtreefs_hooks->rdlink_hook != NULL);
assert(!is_inode_deleted(node)); /* symlinks cannot be opened */
r = vtreefs_hooks->rdlink_hook(node, path, sizeof(path),
get_inode_cbdata(node));
if (r != OK) return r;
len = strlen(path);
assert(len > 0 && len < sizeof(path));
if (len > fs_m_in.m_vfs_fs_rdlink.mem_size)
len = fs_m_in.m_vfs_fs_rdlink.mem_size;
/* Copy out the result. */
r = sys_safecopyto(fs_m_in.m_source, fs_m_in.m_vfs_fs_rdlink.grant, 0,
(vir_bytes) path, len);
if (r != OK) return r;
fs_m_out.m_fs_vfs_rdlink.nbytes = len;
return OK;
}