1 files changed, 37 insertions, 7 deletions

diff --git a/libdiskfs/io-read.c b/libdiskfs/io-read.c
index a5dd148a..787c0eae 100644
--- a/libdiskfs/io-read.c
+++ b/libdiskfs/io-read.c
@@ -1,5 +1,5 @@
 /*
-   Copyright (C) 1994, 1995, 1996 Free Software Foundation
+   Copyright (C) 1994,95,96,97,99,2001 Free Software Foundation
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
@@ -29,7 +29,7 @@ diskfs_S_io_read (struct protid *cred,
 {
   struct node *np;
   int err;
-  int off = offset;
+  off_t off = offset;
   char *buf;
   int ourbuf = 0;
 
@@ -46,6 +46,11 @@ diskfs_S_io_read (struct protid *cred,
 
   if (off == -1)
     off = cred->po->filepointer;
+  if (off < 0)
+    {
+      mutex_unlock (&np->lock);
+      return EINVAL;
+    }
 
   if (off > np->dn_stat.st_size)
     maxread = 0;
@@ -55,24 +60,49 @@ diskfs_S_io_read (struct protid *cred,
   if (maxread > *datalen)
     {
       ourbuf = 1;
-      vm_allocate (mach_task_self (), (u_int *) &buf, maxread, 1);
+      buf = mmap (0, maxread, PROT_READ|PROT_WRITE, MAP_ANON, 0, 0);     
       *data = buf;
     }
   else
     buf = *data;
 
   *datalen = maxread;
-  if (maxread)
+
+  if (maxread == 0)
+    err = 0;
+  else if (S_ISLNK (np->dn_stat.st_mode))
+    {
+      /* Read from a symlink.  */
+      if (! diskfs_read_symlink_hook)
+	err = EINVAL;
+      else
+	{
+	  if (off == 0 && maxread == np->dn_stat.st_size)
+	    err = (*diskfs_read_symlink_hook)(np, buf);
+	  else
+	    {
+	      char *whole_link = alloca (np->dn_stat.st_size);
+	      err = (*diskfs_read_symlink_hook)(np, whole_link);
+	      if (! err)
+		memcpy (buf, whole_link + off, maxread);
+	    }
+	}
+    }
+  else
+    err = EINVAL;		/* Use read below.  */
+
+  if (err == EINVAL)
     err = _diskfs_rdwr_internal (np, buf, off, datalen, 0,
 				 cred->po->openstat & O_NOATIME);
-  else
-    err = 0;
+
   if (diskfs_synchronous)
     diskfs_node_update (np, 1);	/* atime! */
+
   if (offset == -1 && !err)
     cred->po->filepointer += *datalen;
+
   if (err && ourbuf)
-    vm_deallocate (mach_task_self (), (u_int) buf, maxread);
+    munmap (buf, maxread);
 
   mutex_unlock (&np->lock);
   return err;