[lttng-ust.git] / include / lttng / ust-dlfcn.h

/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * dlfcn.h compatibility layer.
 */

#ifndef _LTTNG_UST_DLFCN_H
#define _LTTNG_UST_DLFCN_H

#ifdef _DLFCN_H
#error "Please include lttng/ust-dlfcn.h before dlfcn.h."
#endif /* _DLFCN_H */

#ifdef __GLIBC__
/*
 * glibc declares dlsym() and dlerror() with __attribute__((leaf)) (see
 * THROW annotation). Unfortunately, this is not in sync with reality,
 * as those functions call the memory allocator. Work-around this glibc
 * bug by declaring our own symbols.
 *
 * There has been a similar issue for dlopen() and dlclose(), as
 * constructors and destructors are called from these functions, so they
 * are clearly non-leaf. Work-around the issue for those too for older
 * glibc where these have not been fixed.
 */
#define dlopen glibc_dlopen_proto_lies_about_leafness
#define dlclose glibc_dlclose_proto_lies_about_leafness
#define dlsym glibc_dlsym_proto_lies_about_leafness
#define dlerror glibc_dlerror_proto_lies_about_leafness
#define dlmopen glibc_dlmopen_proto_lies_about_leafness
#define dlvsym glibc_dlvsym_proto_lies_about_leafness
#include <dlfcn.h>
#undef dlvsym
#undef dlmopen
#undef dlerror
#undef dlsym
#undef dlclose
#undef dlopen

extern void *dlopen(__const char *__file, int __mode);
extern int dlclose(void *__handle) __nonnull ((1));
extern void *dlsym(void *__restrict __handle,
		__const char *__restrict __name) __nonnull ((2));
extern char *dlerror(void);
#ifdef __USE_GNU
extern void *dlmopen(Lmid_t __nsid, const char *__file, int __mode);
extern void *dlvsym(void *__restrict __handle,
		__const char *__restrict __name,
		__const char *__restrict __version);
#endif
#else
#include <dlfcn.h>
#endif /* __GLIBC__ */

#endif /* _LTTNG_UST_DLFCN_H */
Commit	Line	Data
	1	/*
	2	* SPDX-License-Identifier: MIT
	3	*
	4	* Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	5	*
	6	* dlfcn.h compatibility layer.
	7	*/
	8
	9	#ifndef _LTTNG_UST_DLFCN_H
	10	#define _LTTNG_UST_DLFCN_H
	11
	12	#ifdef _DLFCN_H
	13	#error "Please include lttng/ust-dlfcn.h before dlfcn.h."
	14	#endif /* _DLFCN_H */
	15
	16	#ifdef __GLIBC__
	17	/*
	18	* glibc declares dlsym() and dlerror() with __attribute__((leaf)) (see
	19	* THROW annotation). Unfortunately, this is not in sync with reality,
	20	* as those functions call the memory allocator. Work-around this glibc
	21	* bug by declaring our own symbols.
	22	*
	23	* There has been a similar issue for dlopen() and dlclose(), as
	24	* constructors and destructors are called from these functions, so they
	25	* are clearly non-leaf. Work-around the issue for those too for older
	26	* glibc where these have not been fixed.
	27	*/
	28	#define dlopen glibc_dlopen_proto_lies_about_leafness
	29	#define dlclose glibc_dlclose_proto_lies_about_leafness
	30	#define dlsym glibc_dlsym_proto_lies_about_leafness
	31	#define dlerror glibc_dlerror_proto_lies_about_leafness
	32	#define dlmopen glibc_dlmopen_proto_lies_about_leafness
	33	#define dlvsym glibc_dlvsym_proto_lies_about_leafness
	34	#include <dlfcn.h>
	35	#undef dlvsym
	36	#undef dlmopen
	37	#undef dlerror
	38	#undef dlsym
	39	#undef dlclose
	40	#undef dlopen
	41
	42	extern void dlopen(__const char __file, int __mode);
	43	extern int dlclose(void *__handle) __nonnull ((1));
	44	extern void dlsym(void __restrict __handle,
	45	__const char *__restrict __name) __nonnull ((2));
	46	extern char *dlerror(void);
	47	#ifdef __USE_GNU
	48	extern void dlmopen(Lmid_t __nsid, const char __file, int __mode);
	49	extern void dlvsym(void __restrict __handle,
	50	__const char *__restrict __name,
	51	__const char *__restrict __version);
	52	#endif
	53	#else
	54	#include <dlfcn.h>
	55	#endif /* __GLIBC__ */
	56
	57	#endif /* _LTTNG_UST_DLFCN_H */