Re: [PATCH 6/8] passt, util: Move opening of PID file to its own function

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

On Wed, May 22, 2024 at 10:59:09PM +0200, Stefano Brivio wrote:
> We won't call it from main() any longer: move it.
> 
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> ---
>  passt.c | 11 ++---------
>  util.c  | 22 ++++++++++++++++++++++
>  util.h  |  1 +
>  3 files changed, 25 insertions(+), 9 deletions(-)
> 
> diff --git a/passt.c b/passt.c
> index fb9773d..e2446fc 100644
> --- a/passt.c
> +++ b/passt.c
> @@ -199,7 +199,7 @@ void exit_handler(int signal)
>   */
>  int main(int argc, char **argv)
>  {
> -	int nfds, i, devnull_fd = -1, pidfile_fd = -1;
> +	int nfds, i, devnull_fd = -1, pidfile_fd;
>  	struct epoll_event events[EPOLL_EVENTS];
>  	char *log_name, argv0[PATH_MAX], *name;
>  	struct ctx c = { 0 };
> @@ -299,14 +299,7 @@ int main(int argc, char **argv)
>  		}
>  	}
>  
> -	if (*c.pid_file) {
> -		if ((pidfile_fd = open(c.pid_file,
> -				       O_CREAT | O_TRUNC | O_WRONLY | O_CLOEXEC,
> -				       S_IRUSR | S_IWUSR)) < 0) {
> -			perror("PID file open");
> -			exit(EXIT_FAILURE);
> -		}
> -	}
> +	pidfile_fd = pidfile_open(c.pid_file);
>  
>  	if (isolate_prefork(&c))
>  		die("Failed to sandbox process, exiting");
> diff --git a/util.c b/util.c
> index 18c04ba..cf5a62b 100644
> --- a/util.c
> +++ b/util.c
> @@ -402,6 +402,28 @@ void pidfile_write(int fd, pid_t pid)
>  	close(fd);
>  }
>  
> +/**
> + * pidfile_open() - Open PID file if needed
> + * @path:	Path for PID file, empty string if no PID file is requested
> + *
> + * Return: descriptor for PID file, -1 if path is NULL, won't return on failure
> + */
> +int pidfile_open(const char *path)
> +{
> +	int fd;
> +
> +	if (!*path)
> +		return -1;
> +
> +	if ((fd = open(path, O_CREAT | O_TRUNC | O_WRONLY | O_CLOEXEC,
> +			     S_IRUSR | S_IWUSR)) < 0) {
> +		perror("PID file open");
> +		exit(EXIT_FAILURE);
> +	}
> +
> +	return fd;
> +}
> +
>  /**
>   * __daemon() - daemon()-like function writing PID file before parent exits
>   * @pidfile_fd:	Open PID file descriptor
> diff --git a/util.h b/util.h
> index f811975..8a430ca 100644
> --- a/util.h
> +++ b/util.h
> @@ -156,6 +156,7 @@ char *line_read(char *buf, size_t len, int fd);
>  void ns_enter(const struct ctx *c);
>  bool ns_is_init(void);
>  int open_in_ns(const struct ctx *c, const char *path, int flags);
> +int pidfile_open(const char *path);
>  void pidfile_write(int fd, pid_t pid);
>  int __daemon(int pidfile_fd, int devnull_fd);
>  int fls(unsigned long x);

Trivial refactoring:

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>

Rich.

-- 
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