Re: [Qemu-devel] [PATCH v3] vl.c: Add '-L help' which lists data dirs.

["Richard W.M. Jones" <rjones@redhat.com>]

Any further objections to this one?  It's a pretty useful
patch for us.

On Mon, May 16, 2016 at 05:34:35PM +0100, Richard W.M. Jones wrote:
> QEMU compiles a list of data directories from various sources.  When
> consuming a QEMU binary it's useful to be able to get this list of
> data directories: a primary reason is so you can list what BIOSes or
> keymaps ship with this version of QEMU.  However without reproducing
> the method that QEMU uses internally, it's not possible to get the
> list of data directories.
> 
> This commit adds a simple '-L help' option that just lists out the
> data directories as qemu calculates them:
> 
> $ ./x86_64-softmmu/qemu-system-x86_64 -L help
> /home/rjones/d/qemu/pc-bios
> /usr/local/share/qemu
> 
> $ ./x86_64-softmmu/qemu-system-x86_64 -L /tmp -L help
> /tmp
> /home/rjones/d/qemu/pc-bios
> /usr/local/share/qemu
> 
> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> ---
>  qemu-options.hx |  2 ++
>  vl.c            | 13 ++++++++++++-
>  2 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 6106520..bec0210 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -3199,6 +3199,8 @@ STEXI
>  @item -L  @var{path}
>  @findex -L
>  Set the directory for the BIOS, VGA BIOS and keymaps.
> +
> +To list all the data directories, use @code{-L help}.
>  ETEXI
>  
>  DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
> diff --git a/vl.c b/vl.c
> index 5fd22cb..d25f2f7 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2990,6 +2990,7 @@ int main(int argc, char **argv, char **envp)
>      FILE *vmstate_dump_file = NULL;
>      Error *main_loop_err = NULL;
>      Error *err = NULL;
> +    bool list_data_dirs = false;
>  
>      qemu_init_cpu_loop();
>      qemu_mutex_lock_iothread();
> @@ -3371,7 +3372,9 @@ int main(int argc, char **argv, char **envp)
>                  add_device_config(DEV_GDB, optarg);
>                  break;
>              case QEMU_OPTION_L:
> -                if (data_dir_idx < ARRAY_SIZE(data_dir)) {
> +                if (is_help_option(optarg)) {
> +                    list_data_dirs = true;
> +                } else if (data_dir_idx < ARRAY_SIZE(data_dir)) {
>                      data_dir[data_dir_idx++] = optarg;
>                  }
>                  break;
> @@ -4128,6 +4131,14 @@ int main(int argc, char **argv, char **envp)
>          data_dir[data_dir_idx++] = CONFIG_QEMU_DATADIR;
>      }
>  
> +    /* -L help lists the data directories and exits. */
> +    if (list_data_dirs) {
> +        for (i = 0; i < data_dir_idx; i++) {
> +            printf("%s\n", data_dir[i]);
> +        }
> +        exit(0);
> +    }
> +
>      smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL));
>  
>      machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */
> -- 
> 2.7.4
> 

Rich.

-- 
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