Joakim Tjernlund/Transmode wrote on 2014/07/14 23:37:02:
> From: Joakim Tjernlund/Transmode
> To:
> Cc: Andreas Färber <afaer...@suse.de>, Alexander Graf <ag...@suse.de>,
qemu-devel@nongnu.org, Riku Voipio <riku.voi...@iki.fi>
> Date: 2014/07/14 23:37
> Subject: Re: [Qemu-devel] [PATCH v2] linux-user: make binfmt flag O
require P
>
> Joakim Tjernlund/Transmode wrote on 2014/07/14 23:04:51:
> > > Why do we need to modify argv[] here when we are building a
> > > target_argv[] further down anyway?
> > Because parse_opts() will not do it for me and I cannot figure out how
to modify
> > parse_opts() whithout breaking it.
>
> I took another look and now I came up with:
>
> From 886985747369947e3b28d7a5fb807abd4beae10c Mon Sep 17 00:00:00 2001
> From: Joakim Tjernlund <joakim.tjernl...@transmode.se>
> Date: Mon, 14 Jul 2014 20:17:28 +0200
> Subject: [PATCH] linux-user: make binfmt flag O require P
>
> QEMU can autodetect if it is started from Linux binfmt loader
> when binfmt flag O is on.
> Use that and require binfmt flag P as well which will enable QEMU
> to pass in correct argv0 to the application.
>
> Signed-off-by: Joakim Tjernlund <joakim.tjernl...@transmode.se>
> ---
> linux-user/main.c | 16 +++++++++++++---
> scripts/qemu-binfmt-conf.sh | 36 ++++++++++++++++++------------------
> 2 files changed, 31 insertions(+), 21 deletions(-)
>
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 71a33c7..845d4e3 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -3750,7 +3750,7 @@ static void usage(void)
> exit(1);
> }
>
> -static int parse_args(int argc, char **argv)
> +static int parse_args(int argc, char **argv, int assume_P_flag)
> {
> const char *r;
> int optind;
> @@ -3768,6 +3768,16 @@ static int parse_args(int argc, char **argv)
> }
>
> optind = 1;
> + if (assume_P_flag) {
> + /* Assume binfmt P flag is set */
> + if (argc < 3) {
> + fprintf(stderr, "%s: Please use me through binfmt with P
flag\n",
> + argv[0]);
> + exit(1);
> + }
> + argv0 = strdup(argv[2]);
> + optind++;
> + }
Well, that broke as soon as logged into my LXC. This works though:
if (assume_P_flag) {
/* Assume binfmt P flag is set */
if (argc < 3) {
fprintf(stderr, "%s: Please use me through binfmt with P
flag\n",
argv[0]);
exit(1);
}
filename = argv[optind];
exec_path = argv[optind];
optind++;
argv0 = strdup(argv[2]);
return optind;
}
Are you happy with that?
Jocke
