On Thu, Jun 22, 2023 at 03:12:48PM +0100, Peter Hoyes wrote:
> diff --git a/tools/include/libxl.h b/tools/include/libxl.h
> index cac641a7eb..c513c39483 100644
> --- a/tools/include/libxl.h
> +++ b/tools/include/libxl.h
> @@ -1958,7 +1958,8 @@ int libxl_vncviewer_exec(libxl_ctx *ctx, uint32_t
> domid, int autopass);
> * the caller that it has connected to the guest console.
> */
> int libxl_console_exec(libxl_ctx *ctx, uint32_t domid, int cons_num,
> - libxl_console_type type, int notify_fd);
> + libxl_console_type type, int notify_fd,
> + char* escape_character);
So, this is changing the libxl API, it's possible, but it's going to be
a bit more complicated than that.
You'll need to:
- Increment LIBXL_API_VERSION, well more like allow a new api version.
That's adding 0x041800 to the list of allowed value for
LIBXL_API_VERSION, at around line 793 in "libxl.h", just before
"#error Unknown LIBXL_API_VERSION".
- Introduce API compatible caller for earlier API version.
A good example of this done would be
libxl_retrieve_domain_configuration_0x041200().
Actually, there's already some changed been made in the past to
libxl_console_exec() and libxl_primary_console_exec(), so those are
probably better example and need to modified.
- Introduce LIBXL_HAVE_* macro in libxl.h to advertise the new arg.
There's already LIBXL_HAVE_CONSOLE_NOTIFY_FD, so I guess the new macro
could be named LIBXL_HAVE_CONSOLE_ESCAPE_CHARACTER.
> /* libxl_primary_console_exec finds the domid and console number
> * corresponding to the primary console of the given vm, then calls
> * libxl_console_exec with the right arguments (domid might be different
> @@ -1968,9 +1969,12 @@ int libxl_console_exec(libxl_ctx *ctx, uint32_t domid,
> int cons_num,
> * guests using pygrub.
> * If notify_fd is not -1, xenconsole will write 0x00 to it to nofity
> * the caller that it has connected to the guest console.
> + * If escape_character is not NULL, the provided value is used to exit
> + * the guest console.
> */
> int libxl_primary_console_exec(libxl_ctx *ctx, uint32_t domid_vm,
> - int notify_fd);
> + int notify_fd,
> + char* escape_character);
>
> #if defined(LIBXL_API_VERSION) && LIBXL_API_VERSION < 0x040800
>
> diff --git a/tools/libs/light/libxl_console.c
> b/tools/libs/light/libxl_console.c
> index f497be141b..0b7293fe71 100644
> --- a/tools/libs/light/libxl_console.c
> +++ b/tools/libs/light/libxl_console.c
> @@ -75,15 +76,26 @@ int libxl_console_exec(libxl_ctx *ctx, uint32_t domid,
> int cons_num,
> goto out;
> }
>
> + char *args[] = {
> + p, domid_s, "--num", cons_num_s, "--type", cons_type_s,
> + NULL, NULL, NULL, NULL, // start-notify-fd, escape
> + NULL, // list terminator - do not use
> + };
> + char **args_extra = args + 6;
> +
> if (notify_fd != -1) {
> notify_fd_s = GCSPRINTF("%d", notify_fd);
> - execl(p, p, domid_s, "--num", cons_num_s, "--type", cons_type_s,
> - "--start-notify-fd", notify_fd_s, (void *)NULL);
> - } else {
> - execl(p, p, domid_s, "--num", cons_num_s, "--type", cons_type_s,
> - (void *)NULL);
> + *args_extra++ = "--start-notify-fd";
> + *args_extra++ = notify_fd_s;
> }
>
> + if (escape_character) {
> + *args_extra++ = "--escape";
> + *args_extra++ = escape_character;
> + }
There is flexarray_* that could be use, but I guess a preset `*args`
kind of work here.
> +
> + execv(p, args);
> +
> out:
> GC_FREE;
> return ERROR_FAIL;
> diff --git a/tools/xl/xl_cmdtable.c b/tools/xl/xl_cmdtable.c
> index ccf4d83584..67604e9536 100644
> --- a/tools/xl/xl_cmdtable.c
> +++ b/tools/xl/xl_cmdtable.c
> @@ -141,7 +141,8 @@ const struct cmd_spec cmd_table[] = {
> "Attach to domain's console",
> "[options] <Domain>\n"
> "-t <type> console type, pv , serial or vuart\n"
> - "-n <number> console number"
> + "-n <number> console number\n"
> + "-e <escape> escape character"
Could you also update "docs/man/xl.1.pod.in" with this new option?
Thanks,
--
Anthony PERARD
