[Bug 13188] command-line kernel debugger kd display problem

http://bugs.winehq.org/show_bug.cgi?id=13188

--- Comment #6 from Yu-Ning Feng   2008-05-16 03:02:15 ---
(In reply to comment #1)

After some effort debugging, I found this bug to be a sync problem.

kd runs in 2 threads. WriteConsole[AW] and ReadConsoleW are in different
threads. Most of the time, CONSOLE_Readline is called before a series of
WriteConsole[AW]. When CONSOLE_Readline is waiting for input at

809     while (!ctx.done && !ctx.error && WCEL_Get(&ctx, &ir))

it will be swapped out, and WriteConsole[AW] is swapped in, updates the window
by some output. When CONSOLE_Readline is swapped in again, the ctx is already
outdated, causing the echo be at a wrong place.

A solution could be to add a GetConsoleScreenBufferInfo between

809     while (!ctx.done && !ctx.error && WCEL_Get(&ctx, &ir))

and

854             SetConsoleCursorPosition(ctx.hConOut, WCEL_GetCoord(&ctx,
ctx.ofs));

As not involved in developing, the solution may be not elegant. With the reason
discovered, however, a proper solution should be easy to get.

Really looking forward to the bug being resolved in the coming release.