[gvfs] smb: Limit blocksize for reading to 65534 to get better performance

[Tomas Bzatek <tbzatek src gnome org>]

commit ce19f20cbb9527131c1d58a1a9565712c4723fa7
Author: Tomas Bzatek <tbzatek redhat com>
Date:   Thu Aug 20 16:44:07 2009 +0200

    smb: Limit blocksize for reading to 65534 to get better performance
    
    "The current code is incredibly inefficient against CIFS servers.
    It asks for a 65535 byte read, which against Windows servers we must
    translate into a 65534 byte read (Windows max) followed by a 1 byte read."
    
    See bug 588391 for details.

 daemon/gvfsbackendsmb.c |   13 +++++++------
 1 files changed, 7 insertions(+), 6 deletions(-)
---
diff --git a/daemon/gvfsbackendsmb.c b/daemon/gvfsbackendsmb.c
index 14a5a58..ae547ab 100644
--- a/daemon/gvfsbackendsmb.c
+++ b/daemon/gvfsbackendsmb.c
@@ -723,12 +723,14 @@ do_read (GVfsBackend *backend,
   ssize_t res;
   smbc_read_fn smbc_read;
 
-  /* For some reason requests of 65536 bytes broke for me (returned 0)
-   * Maybe some smb protocol limit
+  /* libsmbclient limits blocksize to (64*1024)-2 for Windows servers,
+   * let's do the same here to achieve reasonable performance. (#588391)
+   *
+   * TODO: port to pull mechanism (#592468)
    */
-  if (bytes_requested > 65535)
-    bytes_requested = 65535;
-  
+  if (bytes_requested > 65534)
+    bytes_requested = 65534;
+
   smbc_read = smbc_getFunctionRead (op_backend->smb_context);
   res = smbc_read (op_backend->smb_context, (SMBCFILE *)handle, buffer, bytes_requested);
 
@@ -738,7 +740,6 @@ do_read (GVfsBackend *backend,
     {
       g_vfs_job_read_set_size (job, res);
       g_vfs_job_succeeded (G_VFS_JOB (job));
-	    
     }
 }