[lttng-ust.git] / include / usterr-signal-safe.h

#ifndef _USTERR_SIGNAL_SAFE_H
#define _USTERR_SIGNAL_SAFE_H

/*
 * Copyright (C) 2009  Pierre-Marc Fournier
 * Copyright (C) 2011  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; version 2.1 of
 * the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

#include <string.h>
#include <sys/types.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <share.h>
#include "lttng/ust-tid.h"

enum ust_loglevel {
	UST_LOGLEVEL_UNKNOWN = 0,
	UST_LOGLEVEL_NORMAL,
	UST_LOGLEVEL_DEBUG,
};

extern volatile enum ust_loglevel ust_loglevel;
void init_usterr(void);

#ifdef LTTNG_UST_DEBUG
static inline int ust_debug(void)
{
	return 1;
}
#else /* #ifdef LTTNG_UST_DEBUG */
static inline int ust_debug(void)
{
	return ust_loglevel == UST_LOGLEVEL_DEBUG;
}
#endif /* #else #ifdef LTTNG_UST_DEBUG */

#ifndef UST_COMPONENT
//#error UST_COMPONENT is undefined
#define UST_COMPONENT libust
#endif

/* To stringify the expansion of a define */
#define UST_XSTR(d) UST_STR(d)
#define UST_STR(s) #s

#define USTERR_MAX_LEN	512

/* We sometimes print in the tracing path, and tracing can occur in
 * signal handlers, so we must use a print method which is signal safe.
 */

extern int ust_safe_snprintf(char *str, size_t n, const char *fmt, ...)
	__attribute__ ((format (printf, 3, 4)));

/* Can't use dynamic allocation. Limit ourselves to USTERR_MAX_LEN chars. */
/* Add end of string in case of buffer overflow. */
#define sigsafe_print_err(fmt, args...)					\
do {									\
	if (ust_debug()) {						\
		char ____buf[USTERR_MAX_LEN];				\
		int ____saved_errno;					\
									\
		____saved_errno = errno;	/* signal-safety */	\
		ust_safe_snprintf(____buf, sizeof(____buf), fmt, ## args); \
		____buf[sizeof(____buf) - 1] = 0;			\
		patient_write(STDERR_FILENO, ____buf, strlen(____buf));	\
		errno = ____saved_errno;	/* signal-safety */	\
		fflush(stderr);						\
	}								\
} while (0)

#define UST_STR_COMPONENT UST_XSTR(UST_COMPONENT)

#define ERRMSG(fmt, args...)			\
	do {					\
		sigsafe_print_err(UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" UST_XSTR(__LINE__) ")\n", \
		(long) getpid(),		\
		(long) lttng_gettid(),		\
		## args, __func__);		\
	} while(0)


#define DBG(fmt, args...)	ERRMSG(fmt, ## args)
#define DBG_raw(fmt, args...)	sigsafe_print_err(fmt, ## args)
#define WARN(fmt, args...)	ERRMSG("Warning: " fmt, ## args)
#define ERR(fmt, args...)	ERRMSG("Error: " fmt, ## args)
#define BUG(fmt, args...)	ERRMSG("BUG: " fmt, ## args)

#if !defined(__GLIBC__) || ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && !defined(_GNU_SOURCE))
/*
 * Version using XSI strerror_r.
 */
#define PERROR(call, args...)						\
	do {								\
		if (ust_debug()) {					\
			char buf[200] = "Error in strerror_r()";	\
			strerror_r(errno, buf, sizeof(buf));		\
			ERRMSG("Error: " call ": %s", ## args, buf);	\
		}							\
	} while(0)
#else
/*
 * Version using GNU strerror_r, for linux with appropriate defines.
 */
#define PERROR(call, args...)						\
	do {								\
		if (ust_debug()) {					\
			char *buf;					\
			char tmp[200];					\
			buf = strerror_r(errno, tmp, sizeof(tmp));	\
			ERRMSG("Error: " call ": %s", ## args, buf);	\
		}							\
	} while(0)
#endif

#define BUG_ON(condition)					\
	do {							\
		if (caa_unlikely(condition))			\
			ERR("condition not respected (BUG) on line %s:%d", __FILE__, __LINE__);	\
	} while(0)
#define WARN_ON(condition)					\
	do {							\
		if (caa_unlikely(condition))			\
			WARN("condition not respected on line %s:%d", __FILE__, __LINE__); \
	} while(0)
#define WARN_ON_ONCE(condition) WARN_ON(condition)

#endif /* _USTERR_SIGNAL_SAFE_H */
Commit	Line	Data
5e96a467 MD	1	#ifndef _USTERR_SIGNAL_SAFE_H
	2	#define _USTERR_SIGNAL_SAFE_H
	3
	4	/*
	5	* Copyright (C) 2009 Pierre-Marc Fournier
	6	* Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
30ffe279 NC	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
5e96a467 MD	10	* License as published by the Free Software Foundation; version 2.1 of
5e96a467 MD	11	* the License.
30ffe279 NC	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	21	*/
	22
30ffe279 NC	23	#include <string.h>
30ffe279 NC	24	#include <sys/types.h>
30ffe279 NC	25	#include <errno.h>
	26	#include <stdarg.h>
	27	#include <stdio.h>
2f864739	28	#include <share.h>
49c0da7d	29	#include "lttng/ust-tid.h"
30ffe279	30
5e96a467 MD	31	enum ust_loglevel {
	32	UST_LOGLEVEL_UNKNOWN = 0,
	33	UST_LOGLEVEL_NORMAL,
	34	UST_LOGLEVEL_DEBUG,
	35	};
	36
	37	extern volatile enum ust_loglevel ust_loglevel;
	38	void init_usterr(void);
	39
7bdd21a4 MD	40	#ifdef LTTNG_UST_DEBUG
	41	static inline int ust_debug(void)
	42	{
	43	return 1;
	44	}
	45	#else /* #ifdef LTTNG_UST_DEBUG */
5e96a467 MD	46	static inline int ust_debug(void)
	47	{
	48	return ust_loglevel == UST_LOGLEVEL_DEBUG;
	49	}
7bdd21a4	50	#endif /* #else #ifdef LTTNG_UST_DEBUG */
5e96a467	51
30ffe279 NC	52	#ifndef UST_COMPONENT
	53	//#error UST_COMPONENT is undefined
	54	#define UST_COMPONENT libust
	55	#endif
	56
	57	/* To stringify the expansion of a define */
1dbfff0c MD	58	#define UST_XSTR(d) UST_STR(d)
1dbfff0c MD	59	#define UST_STR(s) #s
30ffe279	60
37ed587a MD	61	#define USTERR_MAX_LEN 512
37ed587a MD	62
30ffe279 NC	63	/* We sometimes print in the tracing path, and tracing can occur in
	64	* signal handlers, so we must use a print method which is signal safe.
	65	*/
	66
	67	extern int ust_safe_snprintf(char str, size_t n, const char fmt, ...)
	68	__attribute__ ((format (printf, 3, 4)));
	69
648bb724 MD	70	/* Can't use dynamic allocation. Limit ourselves to USTERR_MAX_LEN chars. */
648bb724 MD	71	/* Add end of string in case of buffer overflow. */
5e96a467	72	#define sigsafe_print_err(fmt, args...) \
648bb724	73	do { \
7bdd21a4 MD	74	if (ust_debug()) { \
	75	char ____buf[USTERR_MAX_LEN]; \
	76	int ____saved_errno; \
	77	\
	78	____saved_errno = errno; /* signal-safety */ \
	79	ust_safe_snprintf(____buf, sizeof(____buf), fmt, ## args); \
	80	____buf[sizeof(____buf) - 1] = 0; \
	81	patient_write(STDERR_FILENO, ____buf, strlen(____buf)); \
	82	errno = ____saved_errno; /* signal-safety */ \
	83	fflush(stderr); \
	84	} \
648bb724	85	} while (0)
30ffe279	86
1dbfff0c	87	#define UST_STR_COMPONENT UST_XSTR(UST_COMPONENT)
30ffe279	88
5e96a467 MD	89	#define ERRMSG(fmt, args...) \
5e96a467 MD	90	do { \
7bdd21a4	91	sigsafe_print_err(UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" UST_XSTR(__LINE__) ")\n", \
5e96a467	92	(long) getpid(), \
0f029713	93	(long) lttng_gettid(), \
5e96a467	94	## args, __func__); \
5e96a467	95	} while(0)
30ffe279	96
7bdd21a4 MD	97
	98	#define DBG(fmt, args...) ERRMSG(fmt, ## args)
	99	#define DBG_raw(fmt, args...) sigsafe_print_err(fmt, ## args)
	100	#define WARN(fmt, args...) ERRMSG("Warning: " fmt, ## args)
	101	#define ERR(fmt, args...) ERRMSG("Error: " fmt, ## args)
	102	#define BUG(fmt, args...) ERRMSG("BUG: " fmt, ## args)
30ffe279	103
b52af467	104	#if !defined(__GLIBC__) \|\| ((_POSIX_C_SOURCE >= 200112L \|\| _XOPEN_SOURCE >= 600) && !defined(_GNU_SOURCE))
9fd26814 MD	105	/*
	106	* Version using XSI strerror_r.
	107	*/
7bdd21a4 MD	108	#define PERROR(call, args...) \
	109	do { \
	110	if (ust_debug()) { \
	111	char buf[200] = "Error in strerror_r()"; \
	112	strerror_r(errno, buf, sizeof(buf)); \
	113	ERRMSG("Error: " call ": %s", ## args, buf); \
	114	} \
	115	} while(0)
30ffe279	116	#else
9fd26814 MD	117	/*
	118	* Version using GNU strerror_r, for linux with appropriate defines.
	119	*/
7bdd21a4 MD	120	#define PERROR(call, args...) \
	121	do { \
	122	if (ust_debug()) { \
	123	char *buf; \
	124	char tmp[200]; \
	125	buf = strerror_r(errno, tmp, sizeof(tmp)); \
	126	ERRMSG("Error: " call ": %s", ## args, buf); \
	127	} \
	128	} while(0)
30ffe279 NC	129	#endif
30ffe279 NC	130
5e96a467 MD	131	#define BUG_ON(condition) \
5e96a467 MD	132	do { \
b5a3dfa5	133	if (caa_unlikely(condition)) \
5e96a467 MD	134	ERR("condition not respected (BUG) on line %s:%d", __FILE__, __LINE__); \
	135	} while(0)
	136	#define WARN_ON(condition) \
	137	do { \
b5a3dfa5	138	if (caa_unlikely(condition)) \
5e96a467 MD	139	WARN("condition not respected on line %s:%d", __FILE__, __LINE__); \
5e96a467 MD	140	} while(0)
30ffe279 NC	141	#define WARN_ON_ONCE(condition) WARN_ON(condition)
	142
	143	#endif /* _USTERR_SIGNAL_SAFE_H */