[PATCH] compositor: Verify XDG_RUNTIME_DIR variable

[Pekka Paalanen]

Hi Martin

On Mon, 18 Jun 2012 20:15:18 +0200
Martin Minarik <minarik11 at student.fiit.stuba.sk> wrote:

> Print an user friendly error mesage when
> the variable is not a valid directory.
> ---
>  src/compositor.c |   34 +++++++++++++++++++++++++++++-----
>  1 files changed, 29 insertions(+), 5 deletions(-)
> 
> diff --git a/src/compositor.c b/src/compositor.c
> index d40a878..f5940aa 100644
> --- a/src/compositor.c
> +++ b/src/compositor.c
> @@ -39,6 +39,7 @@
>  #include <sys/wait.h>
>  #include <sys/socket.h>
>  #include <sys/utsname.h>
> +#include <sys/stat.h>
>  #include <unistd.h>
>  #include <math.h>
>  #include <linux/input.h>
> @@ -3145,11 +3146,37 @@ load_module(const char *name, const char *entrypoint, void **handle)
>  }
>  
>  static const char xdg_error_message[] =
> -	"fatal: environment variable XDG_RUNTIME_DIR is not set.\n"
> +	"fatal: environment variable XDG_RUNTIME_DIR is not set.\n";
> +
> +static const char xdg_wrong_message[] =
> +	"fatal: environment variable XDG_RUNTIME_DIR\n"
> +	"is set to \"%s\". This is not a correct directory.\n";

Let make that like this:
"is set to \"%s\", which is not an existing directory.\n"

If you say "correct directory", the user starts to wonder
what is *the* correct directory. Such information cannot be
found in Google or anywhere else, because it depends, and
there is no single correct answer.

Also you only check that the directory exists, so let's
say that.

> +
> +static const char xdg_detail_message[] =
>  	"Refer to your distribution on how to get it, or\n"
>  	"http://www.freedesktop.org/wiki/Specifications/basedir-spec\n"
>  	"on how to implement it.\n";
>  
> +static void
> +verify_xdg_runtime_dir()
> +{
> +	char * dir = getenv("XDG_RUNTIME_DIR");
> +	struct stat s;
> +
> +	if (!dir) {
> +		weston_log(xdg_error_message);
> +		weston_log_continue(xdg_detail_message);
> +		exit(EXIT_FAILURE);
> +	} else {
> +		stat(dir, &s);
> +		if (!S_ISDIR(s.st_mode)) {
> +			weston_log(xdg_wrong_message, dir);
> +			weston_log_continue(xdg_detail_message);
> +			exit(EXIT_FAILURE);
> +		}
> +	}
> +}
> +
>  int main(int argc, char *argv[])
>  {
>  	int ret = EXIT_SUCCESS;
> @@ -3196,10 +3223,7 @@ int main(int argc, char *argv[])
>  
>  	weston_log_file_open(log);
>  	
> -	if (!getenv("XDG_RUNTIME_DIR")) {
> -		weston_log(xdg_error_message);
> -		exit(EXIT_FAILURE);
> -	}
> +	verify_xdg_runtime_dir();
>  
>  	weston_log("%s\n"
>  		   STAMP_SPACE "%s\n"


Thanks,
pq