Refresh nodes when they're read from the start.

This is necessary for top, for instance, which keeps some files open and
re-reads them regularly. As an extra bonus we can drop the refresh hack.

* procfs.c, procfs.h: Remove the refresh hack.
  (procfs_refresh): New function, invalidates the cached contents.
* netfs.c (netfs_attempt_read, netfs_get_dirents): Call
  procfs_refresh when the read is from offset 0.
* proclist.c (proclist_make_node): Remove the refresh hack.
* dircat.c (dircat_make_node): Likewise.
  (dircat_get_contents): Use procfs_refresh to avoid keeping old data
  from the component nodes.

1 files changed, 6 insertions, 0 deletions

diff --git a/netfs.c b/netfs.c
index e41e062..02a4bf5 100644
--- a/netfs.c
+++ b/netfs.c
@@ -57,6 +57,9 @@ error_t netfs_attempt_read (struct iouser *cred, struct node *np,
   ssize_t contents_len;
   error_t err;
 
+  if (offset == 0)
+    procfs_refresh (np);
+
   err = procfs_get_contents (np, &contents, &contents_len);
   if (err)
     return err;
@@ -139,6 +142,9 @@ error_t netfs_get_dirents (struct iouser *cred, struct node *dir,
   char *contents;
   ssize_t contents_len;
   error_t err;
+
+  if (entry == 0)
+    procfs_refresh (dir);
  
   err = procfs_get_contents (dir, &contents, &contents_len);
   if (err)