1 /* System dependent definitions for run-time dynamic loading. 2 Copyright (C) 1996-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #ifndef _DLFCN_H 20 # error "Never use <bits/dlfcn.h> directly; include <dlfcn.h> instead." 21 #endif 22 23 /* The MODE argument to `dlopen' contains one of the following: */ 24 #define RTLD_LAZY 0x00001 /* Lazy function call binding. */ 25 #define RTLD_NOW 0x00002 /* Immediate function call binding. */ 26 #define RTLD_BINDING_MASK 0x3 /* Mask of binding time value. */ 27 #define RTLD_NOLOAD 0x00004 /* Do not load the object. */ 28 #define RTLD_DEEPBIND 0x00008 /* Use deep binding. */ 29 30 /* If the following bit is set in the MODE argument to `dlopen', 31 the symbols of the loaded object and its dependencies are made 32 visible as if the object were linked directly into the program. */ 33 #define RTLD_GLOBAL 0x00100 34 35 /* Unix98 demands the following flag which is the inverse to RTLD_GLOBAL. 36 The implementation does this by default and so we can define the 37 value to zero. */ 38 #define RTLD_LOCAL 0 39 40 /* Do not delete object when closed. */ 41 #define RTLD_NODELETE 0x01000 42 43 #ifdef __USE_GNU 44 /* To support profiling of shared objects it is a good idea to call 45 the function found using `dlsym' using the following macro since 46 these calls do not use the PLT. But this would mean the dynamic 47 loader has no chance to find out when the function is called. The 48 macro applies the necessary magic so that profiling is possible. 49 Rewrite 50 foo = (*fctp) (arg1, arg2); 51 into 52 foo = DL_CALL_FCT (fctp, (arg1, arg2)); 53 */ 54 # define DL_CALL_FCT(fctp, args) \ 55 (_dl_mcount_wrapper_check ((void *) (fctp)), (*(fctp)) args) 56 57 __BEGIN_DECLS 58 59 /* This function calls the profiling functions. */ 60 extern void _dl_mcount_wrapper_check (void *__selfpc) __THROW; 61 62 __END_DECLS 63 64 #endif 65