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Date: Tue, 30 Aug 2011 19:50:30 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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Subject: [Qemu-devel] broken screendump for text mode?
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I use Qemu 0.15.0 (via a FreeBSD qemu-devel-0.15.0 port) and observe the following
problem with the screendump command.

Environment:
- qemu started with a standard vga adapter emulation (not sure if this important)
- SDL interface is used (not sure if this important)
- guest operating system uses the text mode
- monitor console is activated with Ctrl+Alt+2
- screendump command is executed in the monitor console

I observe the following effects in this case:
- contents of the guest screen is "dumped" over the monitoring console
- produced ppm file has only a single top-most line (of characters) from the guest
screen

It seems that the problem is caused in the vga_draw_text function in hw/vga.c.
The problem is that the dpy_update function is called for each line of text and
only the first of such calls produces the ppm output.

Perhaps in the case when full_update is true there should only be a single
dpy_update call for the whole screen.  I think that this should produce a complete
screen dump.  Not sure if that would help with the guest screen contents being
draw over the monitor console.

Thank you.
-- 
Andriy Gapon