Re: [Qemu-devel] Windows Pipe

[Jiahuan Zhang]

I found the problem! The pipe server and client should be both ready, and
then data transfer can start.

The windows pipe implementation is well-done! Sorry for bothering...

On 1 March 2017 at 16:24, Jiahuan Zhang <address@hidden> wrote:

> I think the reading failure in 2 is because there is no writing to the
> pipe from the frontend (serial port).
>
> So i wonder if the windows pipe implementation is complete. I mean
> dual-way pipe.
>
> From the codes, I sense not. If somebody knows please inform me. 🙏 Thanks
> a lot!
>
> On 1 March 2017 at 16:12, Jiahuan Zhang <address@hidden> wrote:
>
>> What I have done is two things.
>>
>> 1. I create a NamedPipeClient.exe to open the pipe and write a string
>> into it. QEMU indicates the string is recieved from the pipe.
>>
>> 2. I create another NamedPipeClient.exe to open the pipe and read the
>> data in the pipe. In qemu, I run a test.bin as kernel with versatilepb.
>>  test.bin assigns a string to UART0, which is redirected to the pipe.
>> (test.bin has been verified by -serial stdio.) The test result is: pipe is
>> opened by NamedPipeClient.exe, but nothing on the pipe to read.
>>
>> the NamedPipeClient.exe is created by visual studio.
>>
>> On 1 March 2017 at 15:58, Marc-André Lureau <address@hidden>
>> wrote:
>>
>>> Hi
>>>
>>> On Wed, Mar 1, 2017 at 6:42 PM Jiahuan Zhang <address@hidden>
>>> wrote:
>>>
>>>> Hi,
>>>>
>>>> I agree with you about win_chr_poll(). But what I wonder is how to
>>>> write data into the pipe for the host to get. I see "writeFile()" in
>>>> "win_chr_write()", but have no idea how to use it. Or I have to write
>>>> something for this writing. In this case, I don't know what the right
>>>> buffer pointer for WriteFile() is.
>>>>
>>>> Any clue is greatly appreciated!
>>>>
>>>>
>>> According to the documentation, it "creates a single duplex pipe at
>>> \\.pipe\path", you'll have to open and write to it from a different
>>> application. I don't know if there are console applications that can open
>>> pipe you can use, you'll have to do some research or write one!
>>>
>>>
>>> On 1 March 2017 at 15:25, Marc-André Lureau <address@hidden>
>>>> wrote:
>>>>
>>>> Hi
>>>>
>>>> On Wed, Mar 1, 2017 at 5:16 PM Jiahuan Zhang <address@hidden>
>>>> wrote:
>>>>
>>>> Dear QEMU developers,
>>>>
>>>> I want the host-guest communication for QEMU. I want to achieve
>>>> it via serial port redirection to a pipe. My host is windows and guest
>>>> is
>>>> Linux. QEMU is in version 2.8.50
>>>>
>>>> I looked into char-pipe.c and char-win.c, and find that the current QEMU
>>>> only supports reading data on the pipe from host to guest for Windows.
>>>> See *win_chr_pipe_init
>>>> () *in char-pipe.c
>>>>
>>>> Is it true?
>>>>
>>>>
>>>> Not exactly, for some reason, the win-chr-pipe uses a poll,
>>>> win_chr_poll() that read from the pipe and write to the frontend (the vm
>>>> serial).  I haven't tested the windows pipe implementation, only the
>>>> console one, but it looks like it should work. Hopefully someone using qemu
>>>> on windows can help you.
>>>>
>>>>
>>>> I don't know how to use *win_chr_write() *in char-win.c.
>>>> Can you please present an example?
>>>>
>>>> best regards,
>>>> Jiahuan
>>>>
>>>> --
>>>> Marc-André Lureau
>>>>
>>>>
>>>> --
>>> Marc-André Lureau
>>>
>>
>>
>