# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1634079033 -7200
# Node ID 5bb0970d9eb6ef3a1916eb42ec3d9998d9f6bd07
# Parent  8ed52ed7ac888fce1abe53881cd4005b5db87b5b
Introduced a helper method to get parent filesystem objects.

diff -r 8ed52ed7ac88 -r 5bb0970d9eb6 libfsserver/include/fsserver/opener_resource.h
--- a/libfsserver/include/fsserver/opener_resource.h	Mon Oct 11 23:56:21 2021 +0200
+++ b/libfsserver/include/fsserver/opener_resource.h	Wed Oct 13 00:50:33 2021 +0200
@@ -52,6 +52,10 @@
                           offset_t *size, l4_cap_idx_t *cap,
                           object_flags_t *object_flags);
 
+    /* Retrieval methods. */
+
+    virtual long get_parent(const char *path, fileid_t *fileid);
+
     /* Notification methods. */
 
     virtual long notify_parent(const char *path);
diff -r 8ed52ed7ac88 -r 5bb0970d9eb6 libfsserver/lib/files/opener_resource.cc
--- a/libfsserver/lib/files/opener_resource.cc	Mon Oct 11 23:56:21 2021 +0200
+++ b/libfsserver/lib/files/opener_resource.cc	Wed Oct 13 00:50:33 2021 +0200
@@ -48,14 +48,11 @@
 
 
 
-/* Obtain any active parent directory for a path, notifying its subscribers of
-   the file opening event. */
+/* Obtain the identifier for any active parent directory for a path. */
 
-long OpenerResource::notify_parent(const char *path)
+long OpenerResource::get_parent(const char *path, fileid_t *fileid)
 {
     char *sep = strrchr(path, (int) '/');
-    DirectoryProvider *provider;
-    fileid_t fileid;
     long err;
 
     /* For top-level paths, use the empty string to get the root directory.
@@ -63,16 +60,30 @@
        identifier. */
 
     if (sep == NULL)
-        err = get_fileid("", 0, &fileid);
+        err = get_fileid("", 0, fileid);
     else
     {
         char *parent = strndup(path, sep - path + 1);
 
         parent[sep - path] = '\0';
-        err = get_fileid(parent, 0, &fileid);
+        err = get_fileid(parent, 0, fileid);
         free(parent);
     }
 
+    return err;
+}
+
+/* Obtain any active parent directory for a path, notifying its subscribers of
+   the file opening event. */
+
+long OpenerResource::notify_parent(const char *path)
+{
+    DirectoryProvider *provider;
+    fileid_t fileid;
+    long err;
+
+    err = get_parent(path, &fileid);
+
     if (err)
         return err;
 
@@ -98,7 +109,8 @@
 long OpenerResource::open(const char *path, flags_t flags, offset_t *size,
                           l4_cap_idx_t *cap, object_flags_t *object_flags)
 {
-    /* Obtain an identifier for the file, even for new files. */
+    /* Obtain an identifier for the file, even for new files (subject to use of
+       the appropriate flag). */
 
     fileid_t fileid;
     long err = get_fileid(path, flags, &fileid);