[dm-devel] [PATCH 12/35] multipathd: add and set cli_handlers in a single step

[Benjamin Marzinski]

On Fri, Sep 10, 2021 at 01:40:57PM +0200, mwilck at suse.com wrote:
> From: Martin Wilck <mwilck at suse.com>
> 
> Modify set_handler_callback() such that a missing slot is created
> if no matching slot is found. This way, we can skip the initialization
> with NULL handlers on startup.
> 
> Signed-off-by: Martin Wilck <mwilck at suse.com>
> ---
>  multipathd/cli.c | 85 +++++++-----------------------------------------
>  multipathd/cli.h |  6 ++--
>  2 files changed, 15 insertions(+), 76 deletions(-)
> 
> diff --git a/multipathd/cli.c b/multipathd/cli.c
> index 5213813..7020d2b 100644
> --- a/multipathd/cli.c
> +++ b/multipathd/cli.c
> @@ -100,26 +100,20 @@ find_handler (uint64_t fp)
>  }
>  
>  int
> -set_handler_callback (uint64_t fp, cli_handler *fn)
> +__set_handler_callback (uint64_t fp, cli_handler *fn, bool locked)
>  {
> -	struct handler * h = find_handler(fp);
> +	struct handler *h = find_handler(fp);
>  

Wouldn't it be a bug if we reset the handler? Is this really something
we need to check for? Also, if add_handler() just returned a pointer to
the handler, we wouldn't need to call fail_handler() immediately after
creating it.

-Ben

> -	if (!h)
> +	if (!h) {
> +		add_handler(fp, fn);
> +		h = find_handler(fp);
> +	}
> +	if (!h) {
> +		condlog(0, "%s: failed to set handler for code %"PRIu64,
> +			__func__, fp);
>  		return 1;
> -	h->fn = fn;
> -	h->locked = 1;
> -	return 0;
> -}
> -
> -int
> -set_unlocked_handler_callback (uint64_t fp, cli_handler *fn)
> -{
> -	struct handler * h = find_handler(fp);
> -
> -	if (!h)
> -		return 1;
> -	h->fn = fn;
> -	h->locked = 0;
> +	}
> +	h->locked = locked;
>  	return 0;
>  }
>  
> @@ -513,63 +507,6 @@ cli_init (void) {
>  	if (alloc_handlers())
>  		return 1;
>  
> -	add_handler(LIST+PATHS, NULL);
> -	add_handler(LIST+PATHS+FMT, NULL);
> -	add_handler(LIST+PATHS+RAW+FMT, NULL);
> -	add_handler(LIST+PATH, NULL);
> -	add_handler(LIST+STATUS, NULL);
> -	add_handler(LIST+DAEMON, NULL);
> -	add_handler(LIST+MAPS, NULL);
> -	add_handler(LIST+MAPS+STATUS, NULL);
> -	add_handler(LIST+MAPS+STATS, NULL);
> -	add_handler(LIST+MAPS+FMT, NULL);
> -	add_handler(LIST+MAPS+RAW+FMT, NULL);
> -	add_handler(LIST+MAPS+TOPOLOGY, NULL);
> -	add_handler(LIST+MAPS+JSON, NULL);
> -	add_handler(LIST+TOPOLOGY, NULL);
> -	add_handler(LIST+MAP+TOPOLOGY, NULL);
> -	add_handler(LIST+MAP+JSON, NULL);
> -	add_handler(LIST+MAP+FMT, NULL);
> -	add_handler(LIST+MAP+RAW+FMT, NULL);
> -	add_handler(LIST+CONFIG, NULL);
> -	add_handler(LIST+CONFIG+LOCAL, NULL);
> -	add_handler(LIST+BLACKLIST, NULL);
> -	add_handler(LIST+DEVICES, NULL);
> -	add_handler(LIST+WILDCARDS, NULL);
> -	add_handler(RESET+MAPS+STATS, NULL);
> -	add_handler(RESET+MAP+STATS, NULL);
> -	add_handler(ADD+PATH, NULL);
> -	add_handler(DEL+PATH, NULL);
> -	add_handler(ADD+MAP, NULL);
> -	add_handler(DEL+MAP, NULL);
> -	add_handler(DEL+MAPS, NULL);
> -	add_handler(SWITCH+MAP+GROUP, NULL);
> -	add_handler(RECONFIGURE, NULL);
> -	add_handler(SUSPEND+MAP, NULL);
> -	add_handler(RESUME+MAP, NULL);
> -	add_handler(RESIZE+MAP, NULL);
> -	add_handler(RESET+MAP, NULL);
> -	add_handler(RELOAD+MAP, NULL);
> -	add_handler(DISABLEQ+MAP, NULL);
> -	add_handler(RESTOREQ+MAP, NULL);
> -	add_handler(DISABLEQ+MAPS, NULL);
> -	add_handler(RESTOREQ+MAPS, NULL);
> -	add_handler(REINSTATE+PATH, NULL);
> -	add_handler(FAIL+PATH, NULL);
> -	add_handler(QUIT, NULL);
> -	add_handler(SHUTDOWN, NULL);
> -	add_handler(GETPRSTATUS+MAP, NULL);
> -	add_handler(SETPRSTATUS+MAP, NULL);
> -	add_handler(UNSETPRSTATUS+MAP, NULL);
> -	add_handler(GETPRKEY+MAP, NULL);
> -	add_handler(SETPRKEY+MAP+KEY, NULL);
> -	add_handler(UNSETPRKEY+MAP, NULL);
> -	add_handler(FORCEQ+DAEMON, NULL);
> -	add_handler(RESTOREQ+DAEMON, NULL);
> -	add_handler(SETMARGINAL+PATH, NULL);
> -	add_handler(UNSETMARGINAL+PATH, NULL);
> -	add_handler(UNSETMARGINAL+MAP, NULL);
> -
>  	return 0;
>  }
>  
> diff --git a/multipathd/cli.h b/multipathd/cli.h
> index 3dac1b4..dbb75be 100644
> --- a/multipathd/cli.h
> +++ b/multipathd/cli.h
> @@ -134,8 +134,10 @@ struct handler {
>  
>  int alloc_handlers (void);
>  int add_handler (uint64_t fp, cli_handler *fn);
> -int set_handler_callback (uint64_t fp, cli_handler *fn);
> -int set_unlocked_handler_callback (uint64_t fp, cli_handler *fn);
> +int __set_handler_callback (uint64_t fp, cli_handler *fn, bool locked);
> +#define set_handler_callback(fp, fn) __set_handler_callback(fp, fn, true)
> +#define set_unlocked_handler_callback(fp, fn) __set_handler_callback(fp, fn, false)
> +
>  int parse_cmd (char * cmd, char ** reply, int * len, void *, int);
>  int load_keys (void);
>  char * get_keyparam (vector v, uint64_t code);
> -- 
> 2.33.0