[CRIU] [PATCH] Show error messages when failing early in the init process

[Andrei Vagin]

On Fri, Sep 06, 2019 at 07:26:04PM +0000, Nicolas Viennot wrote:
> * Shows an error message when failing to open images directory
> * Fixes chdir() error message logging. Logging is not initialized yet
>   making pr_perror() unavailable.
> 
> Signed-off-by: Nicolas Viennot <nviennot at twosigma.com>
> ---
>  criu/cr-service.c | 2 +-
>  criu/crtools.c    | 8 ++++++--
>  2 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/criu/cr-service.c b/criu/cr-service.c
> index 0938db02..5303eb77 100644
> --- a/criu/cr-service.c
> +++ b/criu/cr-service.c
> @@ -336,7 +336,7 @@ static int setup_opts_from_req(int sk, CriuOpts *req)
>  		SET_CHAR_OPTS(img_parent, req->parent_img);
>  
>  	if (open_image_dir(images_dir_path) < 0) {
> -		pr_perror("Can't open images directory");
> +		pr_perror("Can't open images directory %s", images_dir_path);
>  		goto err;
>  	}
>  
> diff --git a/criu/crtools.c b/criu/crtools.c
> index 97a6d6d6..ab08c894 100644
> --- a/criu/crtools.c
> +++ b/criu/crtools.c
> @@ -147,8 +147,11 @@ int main(int argc, char *argv[], char *envp[])
>  	/* We must not open imgs dir, if service is called */
>  	if (strcmp(argv[optind], "service")) {
>  		ret = open_image_dir(opts.imgs_dir);
> -		if (ret < 0)
> +		if (ret < 0) {
> +			pr_msg("Error: Can't open images directory %s: %s\n",
> +			       opts.imgs_dir, strerror(errno));

This doesn't look right.. We can't write errors to stdout. We need to
think more what we can do here. If we can't write into a log file, we
probably have to write errors to stderr.

>  			return 1;
> +		}
>  	}
>  
>  	/*
> @@ -162,7 +165,8 @@ int main(int argc, char *argv[], char *envp[])
>  		pr_warn("Stopped and detached shell job will get SIGHUP from OS.\n");
>  
>  	if (chdir(opts.work_dir)) {
> -		pr_perror("Can't change directory to %s", opts.work_dir);
> +		pr_msg("Error: Can't change directory to %s: %s\n",
> +		       opts.work_dir, strerror(errno));
>  		return 1;
>  	}
>  
> -- 
> 2.19.1
> 
> 
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