GUACAMOLE-377: Restructure rdp logic to improve graphical data rendering.

[aleitner]

XRPD Connection is noticeably slow. Screen updates take time to occur and appear "laggy".

In this Pull Request we:

• Remove duplicated include statement.
• Consolidate frame start and last frame end timestamps when reading from rdp.
• Change mark frames as 1 (in_frame) when we receive anything but an end frame from RDP (SURFACECMD_FRAMEACTION_END). Otherwise mark frames as 0.

[jmuehlner]

Hey @aleitner, you need a GUACAMOLE issue for any changes you want to submit for review.

[mike-jumper]

Please also be sure to update your commit message to cover the nature of the intended changes. I suspect this may be partly due to this PR being a draft and the overall changes not yet fully known, but "Restructure rdp logic" is too vague.

[mike-jumper]

@aleitner As the support for the Graphics Pipeline Extension / RemoteFX isn't yet complete due to the regression you're looking to address here, the relevant JIRA issue would be the issue introducing that WIP support:

https://issues.apache.org/jira/browse/GUACAMOLE-377

[necouchman]

Looks okay to me - in addition to testing these changes against xrdp, have you also tested against other RDP systems, particularly ones that support RemoteFX, to make sure that it doesn't cause any regressions, there?

[aleitner]

Looks okay to me - in addition to testing these changes against xrdp, have you also tested against other RDP systems, particularly ones that support RemoteFX, to make sure that it doesn't cause any regressions, there?

I have run my code to access

• Windows Server 2016 with RemoteFX enabled.
• Fedora 30 with xrdp 0.9.13
• Ubuntu 22.04 with xrdp 0.9.17

[mike-jumper]

@aleitner Regarding:

Update Surface frame marker to always mark frame as 0 to make sure the frames get flushed appropriately.

Can you clarify why/how this addresses the issue? RDP provides different markers for the start and end of a frame, and setting 0 always for the call to guac_rdp_gdi_mark_frame() would mean that guac_rdp_gdi_mark_frame() always believes it's at the end of a frame and never marks things as being in progress.

[aleitner]

Updated logic by changing to mark frames as 1 (in_frame) when we receive anything but an end frame from RDP (SURFACECMD_FRAMEACTION_END). Otherwise mark frames as 0.

Tested on the following machines

• Windows Server 2016 with RemoteFX enabled.
• Fedora 30 with xrdp 0.9.13
• Ubuntu 22.04 with xrdp 0.9.17

[mike-jumper]

Looks reasonable to me. The issues fixed here are definitely logic errors. I'm intrigued to see how this affects performance after merge.