s3: VFS: vfs_snapper. Implement readlinkat().

Currently identical to readlink().

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Böhme <slow@samba.org>

diff --git a/source3/modules/vfs_snapper.c b/source3/modules/vfs_snapper.c
index cb451ebdcd2ed30e3322326df0cc53c7de1324ba..ce0993806c7686cc0c52a8b9488f15e2f6828ba5 100644 (file)
--- a/source3/modules/vfs_snapper.c
+++ b/source3/modules/vfs_snapper.c
@@ -2381,6 +2381,57 @@ static int snapper_gmt_readlink(vfs_handle_struct *handle,
        return ret;
 }
 
+static int snapper_gmt_readlinkat(vfs_handle_struct *handle,
+                               files_struct *dirfsp,
+                               const struct smb_filename *smb_fname,
+                               char *buf,
+                               size_t bufsiz)
+{
+       time_t timestamp = 0;
+       char *stripped = NULL;
+       int ret;
+       int saved_errno = 0;
+       struct smb_filename *conv = NULL;
+
+       if (!snapper_gmt_strip_snapshot(talloc_tos(), handle,
+                                       smb_fname->base_name,
+                                       &timestamp, &stripped)) {
+               return -1;
+       }
+       if (timestamp == 0) {
+               return SMB_VFS_NEXT_READLINKAT(handle,
+                               dirfsp,
+                               smb_fname,
+                               buf,
+                               bufsiz);
+       }
+       conv = cp_smb_filename(talloc_tos(), smb_fname);
+       if (conv == NULL) {
+               TALLOC_FREE(stripped);
+               errno = ENOMEM;
+               return -1;
+       }
+       conv->base_name = snapper_gmt_convert(conv, handle,
+                                             stripped, timestamp);
+       TALLOC_FREE(stripped);
+       if (conv->base_name == NULL) {
+               return -1;
+       }
+       ret = SMB_VFS_NEXT_READLINKAT(handle,
+                               dirfsp,
+                               conv,
+                               buf,
+                               bufsiz);
+       if (ret == -1) {
+               saved_errno = errno;
+       }
+       TALLOC_FREE(conv);
+       if (saved_errno != 0) {
+               errno = saved_errno;
+       }
+       return ret;
+}
+
 static int snapper_gmt_mknodat(vfs_handle_struct *handle,
                        files_struct *dirfsp,
                        const struct smb_filename *smb_fname,
@@ -2886,6 +2937,7 @@ static struct vfs_fn_pointers snapper_fns = {
        .chdir_fn = snapper_gmt_chdir,
        .ntimes_fn = snapper_gmt_ntimes,
        .readlink_fn = snapper_gmt_readlink,
+       .readlinkat_fn = snapper_gmt_readlinkat,
        .mknodat_fn = snapper_gmt_mknodat,
        .realpath_fn = snapper_gmt_realpath,
        .get_nt_acl_fn = snapper_gmt_get_nt_acl,