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

/*
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * Copyright (C) 2009 Pierre-Marc Fournier
 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#ifndef _USTERR_SIGNAL_SAFE_H
#define _USTERR_SIGNAL_SAFE_H

#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	1	/*
c0c0989a	2	* SPDX-License-Identifier: LGPL-2.1-only
30ffe279	3	*
c0c0989a MJ	4	* Copyright (C) 2009 Pierre-Marc Fournier
c0c0989a MJ	5	* Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
30ffe279 NC	6	*/
30ffe279 NC	7
c0c0989a MJ	8	#ifndef _USTERR_SIGNAL_SAFE_H
	9	#define _USTERR_SIGNAL_SAFE_H
	10
30ffe279 NC	11	#include <string.h>
30ffe279 NC	12	#include <sys/types.h>
30ffe279 NC	13	#include <errno.h>
	14	#include <stdarg.h>
	15	#include <stdio.h>
2f864739	16	#include <share.h>
49c0da7d	17	#include "lttng/ust-tid.h"
30ffe279	18
5e96a467 MD	19	enum ust_loglevel {
	20	UST_LOGLEVEL_UNKNOWN = 0,
	21	UST_LOGLEVEL_NORMAL,
	22	UST_LOGLEVEL_DEBUG,
	23	};
	24
	25	extern volatile enum ust_loglevel ust_loglevel;
	26	void init_usterr(void);
	27
7bdd21a4 MD	28	#ifdef LTTNG_UST_DEBUG
	29	static inline int ust_debug(void)
	30	{
	31	return 1;
	32	}
	33	#else /* #ifdef LTTNG_UST_DEBUG */
5e96a467 MD	34	static inline int ust_debug(void)
	35	{
	36	return ust_loglevel == UST_LOGLEVEL_DEBUG;
	37	}
7bdd21a4	38	#endif /* #else #ifdef LTTNG_UST_DEBUG */
5e96a467	39
30ffe279 NC	40	#ifndef UST_COMPONENT
	41	//#error UST_COMPONENT is undefined
	42	#define UST_COMPONENT libust
	43	#endif
	44
	45	/* To stringify the expansion of a define */
1dbfff0c MD	46	#define UST_XSTR(d) UST_STR(d)
1dbfff0c MD	47	#define UST_STR(s) #s
30ffe279	48
37ed587a MD	49	#define USTERR_MAX_LEN 512
37ed587a MD	50
30ffe279 NC	51	/* We sometimes print in the tracing path, and tracing can occur in
	52	* signal handlers, so we must use a print method which is signal safe.
	53	*/
	54
	55	extern int ust_safe_snprintf(char str, size_t n, const char fmt, ...)
	56	__attribute__ ((format (printf, 3, 4)));
	57
648bb724 MD	58	/* Can't use dynamic allocation. Limit ourselves to USTERR_MAX_LEN chars. */
648bb724 MD	59	/* Add end of string in case of buffer overflow. */
5e96a467	60	#define sigsafe_print_err(fmt, args...) \
648bb724	61	do { \
7bdd21a4 MD	62	if (ust_debug()) { \
	63	char ____buf[USTERR_MAX_LEN]; \
	64	int ____saved_errno; \
	65	\
	66	____saved_errno = errno; /* signal-safety */ \
	67	ust_safe_snprintf(____buf, sizeof(____buf), fmt, ## args); \
	68	____buf[sizeof(____buf) - 1] = 0; \
	69	patient_write(STDERR_FILENO, ____buf, strlen(____buf)); \
	70	errno = ____saved_errno; /* signal-safety */ \
	71	fflush(stderr); \
	72	} \
648bb724	73	} while (0)
30ffe279	74
1dbfff0c	75	#define UST_STR_COMPONENT UST_XSTR(UST_COMPONENT)
30ffe279	76
5e96a467 MD	77	#define ERRMSG(fmt, args...) \
5e96a467 MD	78	do { \
7bdd21a4	79	sigsafe_print_err(UST_STR_COMPONENT "[%ld/%ld]: " fmt " (in %s() at " __FILE__ ":" UST_XSTR(__LINE__) ")\n", \
5e96a467	80	(long) getpid(), \
0f029713	81	(long) lttng_gettid(), \
5e96a467	82	## args, __func__); \
5e96a467	83	} while(0)
30ffe279	84
7bdd21a4 MD	85
	86	#define DBG(fmt, args...) ERRMSG(fmt, ## args)
	87	#define DBG_raw(fmt, args...) sigsafe_print_err(fmt, ## args)
	88	#define WARN(fmt, args...) ERRMSG("Warning: " fmt, ## args)
	89	#define ERR(fmt, args...) ERRMSG("Error: " fmt, ## args)
	90	#define BUG(fmt, args...) ERRMSG("BUG: " fmt, ## args)
30ffe279	91
b52af467	92	#if !defined(__GLIBC__) \|\| ((_POSIX_C_SOURCE >= 200112L \|\| _XOPEN_SOURCE >= 600) && !defined(_GNU_SOURCE))
9fd26814 MD	93	/*
	94	* Version using XSI strerror_r.
	95	*/
7bdd21a4 MD	96	#define PERROR(call, args...) \
	97	do { \
	98	if (ust_debug()) { \
	99	char buf[200] = "Error in strerror_r()"; \
	100	strerror_r(errno, buf, sizeof(buf)); \
	101	ERRMSG("Error: " call ": %s", ## args, buf); \
	102	} \
	103	} while(0)
30ffe279	104	#else
9fd26814 MD	105	/*
	106	* Version using GNU strerror_r, for linux with appropriate defines.
	107	*/
7bdd21a4 MD	108	#define PERROR(call, args...) \
	109	do { \
	110	if (ust_debug()) { \
	111	char *buf; \
	112	char tmp[200]; \
	113	buf = strerror_r(errno, tmp, sizeof(tmp)); \
	114	ERRMSG("Error: " call ": %s", ## args, buf); \
	115	} \
	116	} while(0)
30ffe279 NC	117	#endif
30ffe279 NC	118
5e96a467 MD	119	#define BUG_ON(condition) \
5e96a467 MD	120	do { \
b5a3dfa5	121	if (caa_unlikely(condition)) \
5e96a467 MD	122	ERR("condition not respected (BUG) on line %s:%d", __FILE__, __LINE__); \
	123	} while(0)
	124	#define WARN_ON(condition) \
	125	do { \
b5a3dfa5	126	if (caa_unlikely(condition)) \
5e96a467 MD	127	WARN("condition not respected on line %s:%d", __FILE__, __LINE__); \
5e96a467 MD	128	} while(0)
30ffe279 NC	129	#define WARN_ON_ONCE(condition) WARN_ON(condition)
	130
	131	#endif /* _USTERR_SIGNAL_SAFE_H */