Re: [PATCH 6/9] Mdmonitor: Refactor write_autorebuild_pid()

[Coly Li <colyli@xxxxxxx>]

On 9/7/22 8:56 PM, Mateusz Grzonka wrote:
> Add better error handling and check for symlinks when opening MDMON_DIR.
>
> Signed-off-by: Mateusz Grzonka<mateusz.grzonka@xxxxxxxxx>


Except for the code comment style, the rested part is good to me.

Acked-by: Coly Li <colyli@xxxxxxx>


Thanks.


Coly Li




> ---
>   Monitor.c | 55 ++++++++++++++++++++++++++++++++++++-------------------
>   1 file changed, 36 insertions(+), 19 deletions(-)
>
> diff --git a/Monitor.c b/Monitor.c
> index 80e43ebe..3e09f2a2 100644
> --- a/Monitor.c
> +++ b/Monitor.c
> @@ -33,6 +33,7 @@
>   #endif
>   
>   #define EVENT_NAME_MAX 32
> +#define AUTOREBUILD_PID_PATH MDMON_DIR "/autorebuild.pid"
>   
>   struct state {
>   	char *devname;
> @@ -123,7 +124,7 @@ static int check_udev_activity(void);
>   static void link_containers_with_subarrays(struct state *list);
>   static int make_daemon(char *pidfile);
>   static void try_spare_migration(struct state *statelist);
> -static void write_autorebuild_pid(void);
> +static int write_autorebuild_pid(void);
>   
>   int Monitor(struct mddev_dev *devlist,
>   	    char *mailaddr, char *alert_cmd,
> @@ -224,7 +225,8 @@ int Monitor(struct mddev_dev *devlist,
>   	}
>   
>   	if (share)
> -		write_autorebuild_pid();
> +		if (write_autorebuild_pid() != 0)
> +			return 1;
>   
>   	if (devlist == NULL) {
>   		mdlist = conf_get_ident(NULL);
> @@ -428,29 +430,44 @@ static int check_one_sharer(int scan)
>   	return 0;
>   }
>   
> -static void write_autorebuild_pid()
> +/**
> + * write_autorebuild_pid() - Writes pid to autorebuild.pid file.
> + *
> + * Return: 0 on success, 1 on error
> + */
> +static int write_autorebuild_pid(void)
>   {
> -	char path[PATH_MAX];
> -	int pid;
> -	FILE *fp = NULL;
> -	sprintf(path, "%s/autorebuild.pid", MDMON_DIR);
> +	FILE *fp;
> +	int fd;
>   
>   	if (mkdir(MDMON_DIR, 0700) < 0 && errno != EEXIST) {
> -		pr_err("Can't create autorebuild.pid file\n");
> -	} else {
> -		int fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0700);
> +		pr_err("%s: %s\n", strerror(errno), MDMON_DIR);
> +		return 1;
> +	}
>   
> -		if (fd >= 0)
> -			fp = fdopen(fd, "w");
> +	if (!is_directory(MDMON_DIR)) {
> +		pr_err("%s is not a regular directory.\n", MDMON_DIR);
> +		return 1;
> +	}
>   
> -		if (!fp)
> -			pr_err("Can't create autorebuild.pid file\n");
> -		else {
> -			pid = getpid();
> -			fprintf(fp, "%d\n", pid);
> -			fclose(fp);
> -		}
> +	fd = open(AUTOREBUILD_PID_PATH, O_WRONLY | O_CREAT | O_TRUNC, 0700);
> +
> +	if (fd < 0) {
> +		pr_err("Error opening %s file.\n", AUTOREBUILD_PID_PATH);
> +		return 1;
>   	}
> +
> +	fp = fdopen(fd, "w");
> +
> +	if (!fp) {
> +		pr_err("Error opening fd for %s file.\n", AUTOREBUILD_PID_PATH);
> +		return 1;
> +	}
> +
> +	fprintf(fp, "%d\n", getpid());
> +
> +	fclose(fp);
> +	return 0;
>   }
>   
>   #define BASE_MESSAGE "%s event detected on md device %s"