1 /* User functions for run-time dynamic loading. 2 Copyright (C) 1995-2001,2003,2004,2006,2009 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, write to the Free 17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 18 02111-1307 USA. */ 19 20 #ifndef _DLFCN_H 21 #define _DLFCN_H 1 22 23 #include <features.h> 24 #define __need_size_t 25 #include <stddef.h> 26 27 /* Collect various system dependent definitions and declarations. */ 28 #include <bits/dlfcn.h> 29 30 31 #ifdef __USE_GNU 32 /* If the first argument of `dlsym' or `dlvsym' is set to RTLD_NEXT 33 the run-time address of the symbol called NAME in the next shared 34 object is returned. The "next" relation is defined by the order 35 the shared objects were loaded. */ 36 # define RTLD_NEXT ((void *) -1l) 37 38 /* If the first argument to `dlsym' or `dlvsym' is set to RTLD_DEFAULT 39 the run-time address of the symbol called NAME in the global scope 40 is returned. */ 41 # define RTLD_DEFAULT ((void *) 0) 42 43 44 /* Type for namespace indeces. */ 45 typedef long int Lmid_t; 46 47 /* Special namespace ID values. */ 48 # define LM_ID_BASE 0 /* Initial namespace. */ 49 # define LM_ID_NEWLM -1 /* For dlmopen: request new namespace. */ 50 #endif 51 52 53 __BEGIN_DECLS 54 55 /* Open the shared object FILE and map it in; return a handle that can be 56 passed to `dlsym' to get symbol values from it. */ 57 extern void *dlopen (__const char *__file, int __mode) __THROW; 58 59 /* Unmap and close a shared object opened by `dlopen'. 60 The handle cannot be used again after calling `dlclose'. */ 61 extern int dlclose (void *__handle) __THROW __nonnull ((1)); 62 63 /* Find the run-time address in the shared object HANDLE refers to 64 of the symbol called NAME. */ 65 extern void *dlsym (void *__restrict __handle, 66 __const char *__restrict __name) __THROW __nonnull ((2)); 67 68 #ifdef __USE_GNU 69 /* Like `dlopen', but request object to be allocated in a new namespace. */ 70 extern void *dlmopen (Lmid_t __nsid, __const char *__file, int __mode) __THROW; 71 72 /* Find the run-time address in the shared object HANDLE refers to 73 of the symbol called NAME with VERSION. */ 74 extern void *dlvsym (void *__restrict __handle, 75 __const char *__restrict __name, 76 __const char *__restrict __version) 77 __THROW __nonnull ((2, 3)); 78 #endif 79 80 /* When any of the above functions fails, call this function 81 to return a string describing the error. Each call resets 82 the error string so that a following call returns null. */ 83 extern char *dlerror (void) __THROW; 84 85 86 #ifdef __USE_GNU 87 /* Structure containing information about object searched using 88 `dladdr'. */ 89 typedef struct 90 { 91 __const char *dli_fname; /* File name of defining object. */ 92 void *dli_fbase; /* Load address of that object. */ 93 __const char *dli_sname; /* Name of nearest symbol. */ 94 void *dli_saddr; /* Exact value of nearest symbol. */ 95 } Dl_info; 96 97 /* Fill in *INFO with the following information about ADDRESS. 98 Returns 0 iff no shared object's segments contain that address. */ 99 extern int dladdr (__const void *__address, Dl_info *__info) 100 __THROW __nonnull ((2)); 101 102 /* Same as `dladdr', but additionally sets *EXTRA_INFO according to FLAGS. */ 103 extern int dladdr1 (__const void *__address, Dl_info *__info, 104 void **__extra_info, int __flags) __THROW __nonnull ((2)); 105 106 /* These are the possible values for the FLAGS argument to `dladdr1'. 107 This indicates what extra information is stored at *EXTRA_INFO. 108 It may also be zero, in which case the EXTRA_INFO argument is not used. */ 109 enum 110 { 111 /* Matching symbol table entry (const ElfNN_Sym *). */ 112 RTLD_DL_SYMENT = 1, 113 114 /* The object containing the address (struct link_map *). */ 115 RTLD_DL_LINKMAP = 2 116 }; 117 118 119 /* Get information about the shared object HANDLE refers to. 120 REQUEST is from among the values below, and determines the use of ARG. 121 122 On success, returns zero. On failure, returns -1 and records an error 123 message to be fetched with `dlerror'. */ 124 extern int dlinfo (void *__restrict __handle, 125 int __request, void *__restrict __arg) 126 __THROW __nonnull ((1, 3)); 127 128 /* These are the possible values for the REQUEST argument to `dlinfo'. */ 129 enum 130 { 131 /* Treat ARG as `lmid_t *'; store namespace ID for HANDLE there. */ 132 RTLD_DI_LMID = 1, 133 134 /* Treat ARG as `struct link_map **'; 135 store the `struct link_map *' for HANDLE there. */ 136 RTLD_DI_LINKMAP = 2, 137 138 RTLD_DI_CONFIGADDR = 3, /* Unsupported, defined by Solaris. */ 139 140 /* Treat ARG as `Dl_serinfo *' (see below), and fill in to describe the 141 directories that will be searched for dependencies of this object. 142 RTLD_DI_SERINFOSIZE fills in just the `dls_cnt' and `dls_size' 143 entries to indicate the size of the buffer that must be passed to 144 RTLD_DI_SERINFO to fill in the full information. */ 145 RTLD_DI_SERINFO = 4, 146 RTLD_DI_SERINFOSIZE = 5, 147 148 /* Treat ARG as `char *', and store there the directory name used to 149 expand $ORIGIN in this shared object's dependency file names. */ 150 RTLD_DI_ORIGIN = 6, 151 152 RTLD_DI_PROFILENAME = 7, /* Unsupported, defined by Solaris. */ 153 RTLD_DI_PROFILEOUT = 8, /* Unsupported, defined by Solaris. */ 154 155 /* Treat ARG as `size_t *', and store there the TLS module ID 156 of this object's PT_TLS segment, as used in TLS relocations; 157 store zero if this object does not define a PT_TLS segment. */ 158 RTLD_DI_TLS_MODID = 9, 159 160 /* Treat ARG as `void **', and store there a pointer to the calling 161 thread's TLS block corresponding to this object's PT_TLS segment. 162 Store a null pointer if this object does not define a PT_TLS 163 segment, or if the calling thread has not allocated a block for it. */ 164 RTLD_DI_TLS_DATA = 10, 165 166 RTLD_DI_MAX = 10 167 }; 168 169 170 /* This is the type of elements in `Dl_serinfo', below. 171 The `dls_name' member points to space in the buffer passed to `dlinfo'. */ 172 typedef struct 173 { 174 char *dls_name; /* Name of library search path directory. */ 175 unsigned int dls_flags; /* Indicates where this directory came from. */ 176 } Dl_serpath; 177 178 /* This is the structure that must be passed (by reference) to `dlinfo' for 179 the RTLD_DI_SERINFO and RTLD_DI_SERINFOSIZE requests. */ 180 typedef struct 181 { 182 size_t dls_size; /* Size in bytes of the whole buffer. */ 183 unsigned int dls_cnt; /* Number of elements in `dls_serpath'. */ 184 Dl_serpath dls_serpath[1]; /* Actually longer, dls_cnt elements. */ 185 } Dl_serinfo; 186 #endif /* __USE_GNU */ 187 188 189 __END_DECLS 190 191 #endif /* dlfcn.h */ 192
