[dm-devel] [RFC PATCH 04/20] libmultipath: parser: use call-by-value for "snprint" methods

Benjamin Marzinski bmarzins at redhat.com
Thu Mar 1 05:37:02 UTC 2018


On Tue, Feb 20, 2018 at 02:26:42PM +0100, Martin Wilck wrote:
> Convert the snprint methods for all keywords to call-by-value,
> and use "const" qualifier for the "data" argument. This makes sure
> that "snprint" type functions don't modify the data they're print,
> helps compile-time correctness checking, and allows more proper
> "const" cleanups in the future.
> 

Reviewed-by: Benjamin Marzinski <bmarzins at redhat.com>

> Signed-off-by: Martin Wilck <mwilck at suse.com>
> ---
>  libmultipath/dict.c   | 206 ++++++++++++++++++++++++--------------------------
>  libmultipath/parser.c |   9 ++-
>  libmultipath/parser.h |  12 ++-
>  3 files changed, 112 insertions(+), 115 deletions(-)
> 
> diff --git a/libmultipath/dict.c b/libmultipath/dict.c
> index e52f1f798f7a..47dc2a38f1ac 100644
> --- a/libmultipath/dict.c
> +++ b/libmultipath/dict.c
> @@ -92,46 +92,35 @@ set_yes_no_undef(vector strvec, void *ptr)
>  }
>  
>  static int
> -print_int (char *buff, int len, void *ptr)
> +print_int (char *buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -	return snprintf(buff, len, "%i", *int_ptr);
> +	return snprintf(buff, len, "%li", v);
>  }
>  
>  static int
> -print_nonzero (char *buff, int len, void *ptr)
> +print_nonzero (char *buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -	if (!*int_ptr)
> -		return 0;
> -	return snprintf(buff, len, "%i", *int_ptr);
> +	return snprintf(buff, len, "%li", v);
>  }
>  
>  static int
> -print_str (char *buff, int len, void *ptr)
> +print_str (char *buff, int len, const char *ptr)
>  {
> -	char **str_ptr = (char **)ptr;
> -	if (!*str_ptr)
> -		return 0;
> -	return snprintf(buff, len, "\"%s\"", *str_ptr);
> +	return snprintf(buff, len, "\"%s\"", ptr);
>  }
>  
>  static int
> -print_yes_no (char *buff, int len, void *ptr)
> +print_yes_no (char *buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
>  	return snprintf(buff, len, "\"%s\"",
> -			(*int_ptr == YN_NO)? "no" : "yes");
> +			(v == YN_NO)? "no" : "yes");
>  }
>  
>  static int
> -print_yes_no_undef (char *buff, int len, void *ptr)
> +print_yes_no_undef (char *buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -	if (!*int_ptr)
> -		return 0;
>  	return snprintf(buff, len, "\"%s\"",
> -			(*int_ptr == YNU_NO)? "no" : "yes");
> +			(v == YNU_NO)? "no" : "yes");
>  }
>  
>  #define declare_def_handler(option, function)				\
> @@ -143,29 +132,32 @@ def_ ## option ## _handler (struct config *conf, vector strvec)		\
>  
>  #define declare_def_snprint(option, function)				\
>  static int								\
> -snprint_def_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_def_ ## option (struct config *conf, char * buff, int len,	\
> +			const void * data)				\
>  {									\
> -	return function (buff, len, &conf->option);			\
> +	return function (buff, len, conf->option);			\
>  }
>  
>  #define declare_def_snprint_defint(option, function, value)		\
>  static int								\
> -snprint_def_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_def_ ## option (struct config *conf, char * buff, int len,	\
> +			const void * data)				\
>  {									\
>  	int i = value;							\
>  	if (!conf->option)						\
> -		return function (buff, len, &i);			\
> -	return function (buff, len, &conf->option);			\
> +		return function (buff, len, i);				\
> +	return function (buff, len, conf->option);			\
>  }
>  
>  #define declare_def_snprint_defstr(option, function, value)		\
>  static int								\
> -snprint_def_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_def_ ## option (struct config *conf, char * buff, int len,	\
> +			const void * data)				\
>  {									\
> -	char *s = value;						\
> +	static const char *s = value;					\
>  	if (!conf->option)						\
> -		return function (buff, len, &s);			\
> -	return function (buff, len, &conf->option);			\
> +		return function (buff, len, s);				\
> +	return function (buff, len, conf->option);			\
>  }
>  
>  #define declare_hw_handler(option, function)				\
> @@ -180,10 +172,11 @@ hw_ ## option ## _handler (struct config *conf, vector strvec)		\
>  
>  #define declare_hw_snprint(option, function)				\
>  static int								\
> -snprint_hw_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_hw_ ## option (struct config *conf, char * buff, int len,	\
> +		       const void * data)				\
>  {									\
> -	struct hwentry * hwe = (struct hwentry *)data;			\
> -	return function (buff, len, &hwe->option);			\
> +	const struct hwentry * hwe = (const struct hwentry *)data;	\
> +	return function (buff, len, hwe->option);			\
>  }
>  
>  #define declare_ovr_handler(option, function)				\
> @@ -197,9 +190,10 @@ ovr_ ## option ## _handler (struct config *conf, vector strvec)		\
>  
>  #define declare_ovr_snprint(option, function)				\
>  static int								\
> -snprint_ovr_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_ovr_ ## option (struct config *conf, char * buff, int len,	\
> +			const void * data)				\
>  {									\
> -	return function (buff, len, &conf->overrides->option);		\
> +	return function (buff, len, conf->overrides->option);		\
>  }
>  
>  #define declare_mp_handler(option, function)				\
> @@ -214,10 +208,11 @@ mp_ ## option ## _handler (struct config *conf, vector strvec)		\
>  
>  #define declare_mp_snprint(option, function)				\
>  static int								\
> -snprint_mp_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_mp_ ## option (struct config *conf, char * buff, int len,	\
> +		       const void * data)				\
>  {									\
> -	struct mpentry * mpe = (struct mpentry *)data;			\
> -	return function (buff, len, &mpe->option);			\
> +	const struct mpentry * mpe = (const struct mpentry *)data;	\
> +	return function (buff, len, mpe->option);			\
>  }
>  
>  declare_def_handler(checkint, set_int)
> @@ -328,7 +323,7 @@ declare_mp_snprint(minio_rq, print_nonzero)
>  declare_def_handler(queue_without_daemon, set_yes_no)
>  static int
>  snprint_def_queue_without_daemon (struct config *conf,
> -				  char * buff, int len, void * data)
> +				  char * buff, int len, const void * data)
>  {
>  	switch (conf->queue_without_daemon) {
>  	case QUE_NO_DAEMON_OFF:
> @@ -459,10 +454,11 @@ def_ ## option ## _handler (struct config *conf, vector strvec)		\
>  
>  #define declare_def_attr_snprint(option, function)			\
>  static int								\
> -snprint_def_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_def_ ## option (struct config *conf, char * buff, int len,	\
> +			const void * data)				\
>  {									\
> -	return function (buff, len, &conf->option,			\
> -			 &conf->attribute_flags);			\
> +	return function (buff, len, conf->option,			\
> +			 conf->attribute_flags);			\
>  }
>  
>  #define declare_mp_attr_handler(option, function)			\
> @@ -477,11 +473,12 @@ mp_ ## option ## _handler (struct config *conf, vector strvec)		\
>  
>  #define declare_mp_attr_snprint(option, function)			\
>  static int								\
> -snprint_mp_ ## option (struct config *conf, char * buff, int len, void * data) \
> +snprint_mp_ ## option (struct config *conf, char * buff, int len,	\
> +		       const void * data)				\
>  {									\
> -	struct mpentry * mpe = (struct mpentry *)data;			\
> -	return function (buff, len, &mpe->option,			\
> -			 &mpe->attribute_flags);			\
> +	const struct mpentry * mpe = (const struct mpentry *)data;	\
> +	return function (buff, len, mpe->option,			\
> +			 mpe->attribute_flags);				\
>  }
>  
>  static int
> @@ -556,30 +553,30 @@ set_gid(vector strvec, void *ptr, int *flags)
>  }
>  
>  static int
> -print_mode(char * buff, int len, void *ptr, int *flags)
> +print_mode(char * buff, int len, long v, int flags)
>  {
> -	mode_t *mode_ptr = (mode_t *)ptr;
> -	if ((*flags & (1 << ATTR_MODE)) == 0)
> +	mode_t mode = (mode_t)v;
> +	if ((flags & (1 << ATTR_MODE)) == 0)
>  		return 0;
> -	return snprintf(buff, len, "0%o", *mode_ptr);
> +	return snprintf(buff, len, "0%o", mode);
>  }
>  
>  static int
> -print_uid(char * buff, int len, void *ptr, int *flags)
> +print_uid(char * buff, int len, long v, int flags)
>  {
> -	uid_t *uid_ptr = (uid_t *)ptr;
> -	if ((*flags & (1 << ATTR_UID)) == 0)
> +	uid_t uid = (uid_t)v;
> +	if ((flags & (1 << ATTR_UID)) == 0)
>  		return 0;
> -	return snprintf(buff, len, "0%o", *uid_ptr);
> +	return snprintf(buff, len, "0%o", uid);
>  }
>  
>  static int
> -print_gid(char * buff, int len, void *ptr, int *flags)
> +print_gid(char * buff, int len, long v, int flags)
>  {
> -	gid_t *gid_ptr = (gid_t *)ptr;
> -	if ((*flags & (1 << ATTR_GID)) == 0)
> +	gid_t gid = (gid_t)v;
> +	if ((flags & (1 << ATTR_GID)) == 0)
>  		return 0;
> -	return snprintf(buff, len, "0%o", *gid_ptr);
> +	return snprintf(buff, len, "0%o", gid);
>  }
>  
>  declare_def_attr_handler(mode, set_mode)
> @@ -620,17 +617,15 @@ set_fast_io_fail(vector strvec, void *ptr)
>  }
>  
>  int
> -print_fast_io_fail(char * buff, int len, void *ptr)
> +print_fast_io_fail(char * buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -
> -	if (*int_ptr == MP_FAST_IO_FAIL_UNSET)
> +	if (v == MP_FAST_IO_FAIL_UNSET)
>  		return 0;
> -	if (*int_ptr == MP_FAST_IO_FAIL_OFF)
> +	if (v == MP_FAST_IO_FAIL_OFF)
>  		return snprintf(buff, len, "\"off\"");
> -	if (*int_ptr == MP_FAST_IO_FAIL_ZERO)
> +	if (v == MP_FAST_IO_FAIL_ZERO)
>  		return snprintf(buff, len, "0");
> -	return snprintf(buff, len, "%d", *int_ptr);
> +	return snprintf(buff, len, "%ld", v);
>  }
>  
>  declare_def_handler(fast_io_fail, set_fast_io_fail)
> @@ -660,15 +655,11 @@ set_dev_loss(vector strvec, void *ptr)
>  }
>  
>  int
> -print_dev_loss(char * buff, int len, void *ptr)
> +print_dev_loss(char * buff, int len, unsigned long v)
>  {
> -	unsigned int *uint_ptr = (unsigned int *)ptr;
> -
> -	if (!*uint_ptr)
> -		return 0;
> -	if (*uint_ptr >= MAX_DEV_LOSS_TMO)
> +	if (v >= MAX_DEV_LOSS_TMO)
>  		return snprintf(buff, len, "\"infinity\"");
> -	return snprintf(buff, len, "%u", *uint_ptr);
> +	return snprintf(buff, len, "%lu", v);
>  }
>  
>  declare_def_handler(dev_loss, set_dev_loss)
> @@ -695,10 +686,9 @@ set_pgpolicy(vector strvec, void *ptr)
>  }
>  
>  int
> -print_pgpolicy(char * buff, int len, void *ptr)
> +print_pgpolicy(char * buff, int len, long pgpolicy)
>  {
>  	char str[POLICY_NAME_SIZE];
> -	int pgpolicy = *(int *)ptr;
>  
>  	if (!pgpolicy)
>  		return 0;
> @@ -776,7 +766,7 @@ max_fds_handler(struct config *conf, vector strvec)
>  }
>  
>  static int
> -snprint_max_fds (struct config *conf, char * buff, int len, void * data)
> +snprint_max_fds (struct config *conf, char * buff, int len, const void * data)
>  {
>  	int r = 0, max_fds;
>  
> @@ -813,15 +803,13 @@ set_rr_weight(vector strvec, void *ptr)
>  }
>  
>  int
> -print_rr_weight (char * buff, int len, void *ptr)
> +print_rr_weight (char * buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -
> -	if (!*int_ptr)
> +	if (!v)
>  		return 0;
> -	if (*int_ptr == RR_WEIGHT_PRIO)
> +	if (v == RR_WEIGHT_PRIO)
>  		return snprintf(buff, len, "\"priorities\"");
> -	if (*int_ptr == RR_WEIGHT_NONE)
> +	if (v == RR_WEIGHT_NONE)
>  		return snprintf(buff, len, "\"uniform\"");
>  
>  	return 0;
> @@ -861,11 +849,9 @@ set_pgfailback(vector strvec, void *ptr)
>  }
>  
>  int
> -print_pgfailback (char * buff, int len, void *ptr)
> +print_pgfailback (char * buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -
> -	switch(*int_ptr) {
> +	switch(v) {
>  	case  FAILBACK_UNDEF:
>  		return 0;
>  	case -FAILBACK_MANUAL:
> @@ -875,7 +861,7 @@ print_pgfailback (char * buff, int len, void *ptr)
>  	case -FAILBACK_FOLLOWOVER:
>  		return snprintf(buff, len, "\"followover\"");
>  	default:
> -		return snprintf(buff, len, "%i", *int_ptr);
> +		return snprintf(buff, len, "%li", v);
>  	}
>  }
>  
> @@ -910,11 +896,9 @@ set_no_path_retry(vector strvec, void *ptr)
>  }
>  
>  int
> -print_no_path_retry(char * buff, int len, void *ptr)
> +print_no_path_retry(char * buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -
> -	switch(*int_ptr) {
> +	switch(v) {
>  	case NO_PATH_RETRY_UNDEF:
>  		return 0;
>  	case NO_PATH_RETRY_FAIL:
> @@ -922,7 +906,7 @@ print_no_path_retry(char * buff, int len, void *ptr)
>  	case NO_PATH_RETRY_QUEUE:
>  		return snprintf(buff, len, "\"queue\"");
>  	default:
> -		return snprintf(buff, len, "%i", *int_ptr);
> +		return snprintf(buff, len, "%li", v);
>  	}
>  }
>  
> @@ -955,7 +939,8 @@ def_log_checker_err_handler(struct config *conf, vector strvec)
>  }
>  
>  static int
> -snprint_def_log_checker_err (struct config *conf, char * buff, int len, void * data)
> +snprint_def_log_checker_err (struct config *conf, char * buff, int len,
> +			     const void * data)
>  {
>  	if (conf->log_checker_err == LOG_CHKR_ERR_ONCE)
>  		return snprintf(buff, len, "once");
> @@ -1008,7 +993,7 @@ def_reservation_key_handler(struct config *conf, vector strvec)
>  
>  static int
>  snprint_def_reservation_key (struct config *conf, char * buff, int len,
> -			     void * data)
> +			     const void * data)
>  {
>  	return print_reservation_key(buff, len, conf->reservation_key,
>  				     conf->prkey_source);
> @@ -1026,9 +1011,9 @@ mp_reservation_key_handler(struct config *conf, vector strvec)
>  
>  static int
>  snprint_mp_reservation_key (struct config *conf, char * buff, int len,
> -			     void * data)
> +			    const void * data)
>  {
> -	struct mpentry * mpe = (struct mpentry *)data;
> +	const struct mpentry * mpe = (const struct mpentry *)data;
>  	return print_reservation_key(buff, len, mpe->reservation_key,
>  				     mpe->prkey_source);
>  }
> @@ -1053,17 +1038,15 @@ set_off_int_undef(vector strvec, void *ptr)
>  }
>  
>  int
> -print_off_int_undef(char * buff, int len, void *ptr)
> +print_off_int_undef(char * buff, int len, long v)
>  {
> -	int *int_ptr = (int *)ptr;
> -
> -	switch(*int_ptr) {
> +	switch(v) {
>  	case NU_UNDEF:
>  		return 0;
>  	case NU_NO:
>  		return snprintf(buff, len, "\"no\"");
>  	default:
> -		return snprintf(buff, len, "%i", *int_ptr);
> +		return snprintf(buff, len, "%li", v);
>  	}
>  }
>  
> @@ -1231,15 +1214,17 @@ declare_ble_handler(blist_property)
>  declare_ble_handler(elist_property)
>  
>  static int
> -snprint_def_uxsock_timeout(struct config *conf, char * buff, int len, void * data)
> +snprint_def_uxsock_timeout(struct config *conf, char * buff, int len,
> +			   const void * data)
>  {
>  	return snprintf(buff, len, "%u", conf->uxsock_timeout);
>  }
>  
>  static int
> -snprint_ble_simple (struct config *conf, char * buff, int len, void * data)
> +snprint_ble_simple (struct config *conf, char * buff, int len,
> +		    const void * data)
>  {
> -	struct blentry * ble = (struct blentry *)data;
> +	const struct blentry * ble = (const struct blentry *)data;
>  
>  	return snprintf(buff, len, "\"%s\"", ble->str);
>  }
> @@ -1262,17 +1247,21 @@ declare_ble_device_handler(product, blist_device, NULL, buff)
>  declare_ble_device_handler(product, elist_device, NULL, buff)
>  
>  static int
> -snprint_bled_vendor (struct config *conf, char * buff, int len, void * data)
> +snprint_bled_vendor (struct config *conf, char * buff, int len,
> +		     const void * data)
>  {
> -	struct blentry_device * bled = (struct blentry_device *)data;
> +	const struct blentry_device * bled =
> +		(const struct blentry_device *)data;
>  
>  	return snprintf(buff, len, "\"%s\"", bled->vendor);
>  }
>  
>  static int
> -snprint_bled_product (struct config *conf, char * buff, int len, void * data)
> +snprint_bled_product (struct config *conf, char * buff, int len,
> +		      const void * data)
>  {
> -	struct blentry_device * bled = (struct blentry_device *)data;
> +	const struct blentry_device * bled =
> +		(const struct blentry_device *)data;
>  
>  	return snprintf(buff, len, "\"%s\"", bled->product);
>  }
> @@ -1402,7 +1391,8 @@ deprecated_handler(struct config *conf, vector strvec)
>  }
>  
>  static int
> -snprint_deprecated (struct config *conf, char * buff, int len, void * data)
> +snprint_deprecated (struct config *conf, char * buff, int len,
> +		    const void * data)
>  {
>  	return 0;
>  }
> diff --git a/libmultipath/parser.c b/libmultipath/parser.c
> index c47d891ec369..5caa2019a1a4 100644
> --- a/libmultipath/parser.c
> +++ b/libmultipath/parser.c
> @@ -33,7 +33,8 @@ static int line_nr;
>  int
>  keyword_alloc(vector keywords, char *string,
>  	      int (*handler) (struct config *, vector),
> -	      int (*print) (struct config *, char *, int, void *), int unique)
> +	      int (*print) (struct config *, char *, int, const void*),
> +	      int unique)
>  {
>  	struct keyword *keyword;
>  
> @@ -71,7 +72,8 @@ install_sublevel_end(void)
>  int
>  _install_keyword(vector keywords, char *string,
>  		 int (*handler) (struct config *, vector),
> -		 int (*print) (struct config *, char *, int, void *), int unique)
> +		 int (*print) (struct config *, char *, int, const void*),
> +		 int unique)
>  {
>  	int i = 0;
>  	struct keyword *keyword;
> @@ -143,7 +145,8 @@ find_keyword(vector keywords, vector v, char * name)
>  }
>  
>  int
> -snprint_keyword(char *buff, int len, char *fmt, struct keyword *kw, void *data)
> +snprint_keyword(char *buff, int len, char *fmt, struct keyword *kw,
> +		const void *data)
>  {
>  	int r;
>  	int fwd = 0;
> diff --git a/libmultipath/parser.h b/libmultipath/parser.h
> index 519b805d4149..0a747507d7be 100644
> --- a/libmultipath/parser.h
> +++ b/libmultipath/parser.h
> @@ -43,7 +43,7 @@
>  struct keyword {
>  	char *string;
>  	int (*handler) (struct config *, vector);
> -	int (*print) (struct config *, char *, int, void *);
> +	int (*print) (struct config *, char *, int, const void *);
>  	vector sub;
>  	int unique;
>  };
> @@ -60,13 +60,17 @@ struct keyword {
>  /* Prototypes */
>  extern int keyword_alloc(vector keywords, char *string,
>  			 int (*handler) (struct config *, vector),
> -			 int (*print) (struct config *, char *, int, void *), int unique);
> +			 int (*print) (struct config *, char *, int,
> +				       const void *),
> +			 int unique);
>  #define install_keyword_root(str, h) keyword_alloc(keywords, str, h, NULL, 1)
>  extern void install_sublevel(void);
>  extern void install_sublevel_end(void);
>  extern int _install_keyword(vector keywords, char *string,
>  			    int (*handler) (struct config *, vector),
> -			    int (*print) (struct config *, char *, int, void *), int unique);
> +			    int (*print) (struct config *, char *, int,
> +					  const void *),
> +			    int unique);
>  #define install_keyword(str, vec, pri) _install_keyword(keywords, str, vec, pri, 1)
>  #define install_keyword_multi(str, vec, pri) _install_keyword(keywords, str, vec, pri, 0)
>  extern void dump_keywords(vector keydump, int level);
> @@ -76,6 +80,6 @@ extern void *set_value(vector strvec);
>  extern int process_file(struct config *conf, char *conf_file);
>  extern struct keyword * find_keyword(vector keywords, vector v, char * name);
>  int snprint_keyword(char *buff, int len, char *fmt, struct keyword *kw,
> -		    void *data);
> +		    const void *data);
>  
>  #endif
> -- 
> 2.16.1




More information about the dm-devel mailing list