Re: [PATCH 2/2] chardev: Allow setting file chardev input file on the command line

[Thomas Huth <thuth@redhat.com>]

On 13/04/2023 17.07, Peter Maydell wrote:
> Our 'file' chardev backend supports both "output from this chardev
> is written to a file" and "input from this chardev should be read
> from a file" (except on Windows). However, you can only set up
> the input file if you're using the QMP interface -- there is no
> command line syntax to do it.
> 
> Add command line syntax to allow specifying an input file
> as well as an output file, using a new 'input-path' suboption.
> 
> The specific use case I have is that I'd like to be able to
> feed fuzzer reproducer input into qtest without having to use
> '-qtest stdio' and put the input onto stdin. Being able to
> use a file chardev like this:
>   -chardev file,id=repro,path=/dev/null,input-path=repro.txt -qtest chardev:repro
> means that stdio is free for use by gdb.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
...
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 59bdf67a2c5..31d08c60264 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -3360,7 +3360,7 @@ DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
>       "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
>       "         [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
>       "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
> -    "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
> +    "-chardev file,id=id,path=path[,input-file=input-file][,mux=on|off][,logfile=PATH][,logappend=on|off]\n"

s/input-file=/input-path=/

  Thomas