[CRIU] [PATCH] image: open_img_dir(): add more informative var names and error handling

[Pavel Emelyanov]

On 11/18/2013 12:10 AM, Ruslan Kuprieiev wrote:
> Add informative names for fds and add one exit point.
> 
> Signed-off-by: Ruslan Kuprieiev <kupruser at gmail.com>
> ---
>  image.c | 44 +++++++++++++++++++++++++-------------------
>  1 file changed, 25 insertions(+), 19 deletions(-)
> 
> diff --git a/image.c b/image.c
> index d696bdb..614478c 100644
> --- a/image.c
> +++ b/image.c
> @@ -231,41 +231,47 @@ err:
>  
>  int open_image_dir(char *dir)
>  {
> -	int fd1, fd2, ret;
> +	int imgs_dir_fd, parent_dir_fd;
> +	int ret = 0;
>  
> -	fd1 = open(dir, O_RDONLY);
> -	if (fd1 < 0) {
> +	imgs_dir_fd = open(dir, O_RDONLY);
> +	if (imgs_dir_fd < 0) {
>  		pr_perror("Can't open dir %s", dir);
> -		return -1;
> +		goto exit;

This goto exit; will result in call to close_safe(&parent_dir_fd) with
uninitialized parent_dir_fd.

>  	}
>  
> -	ret = install_service_fd(IMG_FD_OFF, fd1);
> +	ret = install_service_fd(IMG_FD_OFF, imgs_dir_fd);
> +	if (ret < 0) {
> +		pr_perror("Can't install images dir fd");
> +		goto exit;
> +	}
>  
>  	if (opts.img_parent) {
> -		ret = symlinkat(opts.img_parent, fd1, CR_PARENT_LINK);
> +		ret = symlinkat(opts.img_parent, imgs_dir_fd, CR_PARENT_LINK);
>  		if (ret < 0) {
>  			pr_perror("Can't link parent snapshot.");
> -			goto err;
> +			goto exit;
>  		}
>  
> -		fd2 = openat(fd1, CR_PARENT_LINK, O_RDONLY);
> -		if (fd2 < 0) {
> +		parent_dir_fd = openat(imgs_dir_fd, CR_PARENT_LINK, O_RDONLY);
> +		if (parent_dir_fd < 0) {
>  			pr_perror("Can't open parent snapshot.");
> -			goto err;
> +			goto exit;
>  		}
>  
> -		ret = install_service_fd(PARENT_FD_OFF, fd2);
> -
> -		close(fd2);
> +		ret = install_service_fd(PARENT_FD_OFF, parent_dir_fd);
> +		if (ret < 0) {
> +			pr_perror("Can't install parent snapshot dir fd");
> +			goto exit;
> +		}
>  	}
>  
> -	close(fd1);
> -
> +exit:
> +	close_safe(&imgs_dir_fd);
> +	close_safe(&parent_dir_fd);
> +	if (ret < 0)
> +		close_image_dir();
>  	return ret;
> -
> -err:
> -	close_image_dir();
> -	return -1;
>  }
>  
>  void close_image_dir(void)
>