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, see 17 <http://www.gnu.org/licenses/>. */ 18 19 #ifndef _DLFCN_H 20 #define _DLFCN_H 1 21 22 #include <features.h> 23 #define __need_size_t 24 #include <stddef.h> 25 26 /* Collect various system dependent definitions and declarations. */ 27 #include <bits/dlfcn.h> 28 29 /* Internally used flag. */ 30 #define __RTLD_SECURE 0x04000000 /* Apply additional security checks. */ 31 32 33 #ifdef __USE_GNU 34 /* If the first argument of `dlsym' or `dlvsym' is set to RTLD_NEXT 35 the run-time address of the symbol called NAME in the next shared 36 object is returned. The "next" relation is defined by the order 37 the shared objects were loaded. */ 38 # define RTLD_NEXT ((void *) -1l) 39 40 /* If the first argument to `dlsym' or `dlvsym' is set to RTLD_DEFAULT 41 the run-time address of the symbol called NAME in the global scope 42 is returned. */ 43 # define RTLD_DEFAULT ((void *) 0) 44 45 46 # if 0 /* uClibc doesnt support this */ 47 /* Type for namespace indeces. */ 48 typedef long int Lmid_t; 49 50 /* Special namespace ID values. */ 51 # define LM_ID_BASE 0 /* Initial namespace. */ 52 # define LM_ID_NEWLM -1 /* For dlmopen: request new namespace. */ 53 # endif 54 #endif 55 56 57 __BEGIN_DECLS 58 59 /* Open the shared object FILE and map it in; return a handle that can be 60 passed to `dlsym' to get symbol values from it. */ 61 extern void *dlopen (const char *__file, int __mode) __THROWNL; 62 63 /* Unmap and close a shared object opened by `dlopen'. 64 The handle cannot be used again after calling `dlclose'. */ 65 extern int dlclose (void *__handle) __THROWNL __nonnull ((1)); 66 67 /* Find the run-time address in the shared object HANDLE refers to 68 of the symbol called NAME. */ 69 extern void *dlsym (void *__restrict __handle, 70 const char *__restrict __name) __THROW __nonnull ((2)); 71 72 #if 0 /*def __USE_GNU*/ 73 /* Like `dlopen', but request object to be allocated in a new namespace. */ 74 extern void *dlmopen (Lmid_t __nsid, const char *__file, int __mode) __THROWNL; 75 76 /* Find the run-time address in the shared object HANDLE refers to 77 of the symbol called NAME with VERSION. */ 78 extern void *dlvsym (void *__restrict __handle, 79 const char *__restrict __name, 80 const char *__restrict __version) 81 __THROW __nonnull ((2, 3)); 82 #endif 83 84 /* When any of the above functions fails, call this function 85 to return a string describing the error. Each call resets 86 the error string so that a following call returns null. */ 87 extern char *dlerror (void) __THROW; 88 89 90 #ifdef __USE_GNU 91 /* Structure containing information about object searched using 92 `dladdr'. */ 93 typedef struct 94 { 95 const char *dli_fname; /* File name of defining object. */ 96 void *dli_fbase; /* Load address of that object. */ 97 const char *dli_sname; /* Name of nearest symbol. */ 98 void *dli_saddr; /* Exact value of nearest symbol. */ 99 } Dl_info; 100 101 /* Fill in *INFO with the following information about ADDRESS. 102 Returns 0 iff no shared object's segments contain that address. */ 103 extern int dladdr (const void *__address, Dl_info *__info) 104 __THROW __nonnull ((2)); 105 106 #if 0 /* not supported by uClibc */ 107 /* Same as `dladdr', but additionally sets *EXTRA_INFO according to FLAGS. */ 108 extern int dladdr1 (const void *__address, Dl_info *__info, 109 void **__extra_info, int __flags) __THROW __nonnull ((2)); 110 111 /* These are the possible values for the FLAGS argument to `dladdr1'. 112 This indicates what extra information is stored at *EXTRA_INFO. 113 It may also be zero, in which case the EXTRA_INFO argument is not used. */ 114 enum 115 { 116 /* Matching symbol table entry (const ElfNN_Sym *). */ 117 RTLD_DL_SYMENT = 1, 118 119 /* The object containing the address (struct link_map *). */ 120 RTLD_DL_LINKMAP = 2 121 }; 122 123 124 /* Get information about the shared object HANDLE refers to. 125 REQUEST is from among the values below, and determines the use of ARG. 126 127 On success, returns zero. On failure, returns -1 and records an error 128 message to be fetched with `dlerror'. */ 129 extern int dlinfo (void *__restrict __handle, 130 int __request, void *__restrict __arg) 131 __THROW __nonnull ((1, 3)); 132 133 /* These are the possible values for the REQUEST argument to `dlinfo'. */ 134 enum 135 { 136 /* Treat ARG as `lmid_t *'; store namespace ID for HANDLE there. */ 137 RTLD_DI_LMID = 1, 138 139 /* Treat ARG as `struct link_map **'; 140 store the `struct link_map *' for HANDLE there. */ 141 RTLD_DI_LINKMAP = 2, 142 143 RTLD_DI_CONFIGADDR = 3, /* Unsupported, defined by Solaris. */ 144 145 /* Treat ARG as `Dl_serinfo *' (see below), and fill in to describe the 146 directories that will be searched for dependencies of this object. 147 RTLD_DI_SERINFOSIZE fills in just the `dls_cnt' and `dls_size' 148 entries to indicate the size of the buffer that must be passed to 149 RTLD_DI_SERINFO to fill in the full information. */ 150 RTLD_DI_SERINFO = 4, 151 RTLD_DI_SERINFOSIZE = 5, 152 153 /* Treat ARG as `char *', and store there the directory name used to 154 expand $ORIGIN in this shared object's dependency file names. */ 155 RTLD_DI_ORIGIN = 6, 156 157 RTLD_DI_PROFILENAME = 7, /* Unsupported, defined by Solaris. */ 158 RTLD_DI_PROFILEOUT = 8, /* Unsupported, defined by Solaris. */ 159 160 /* Treat ARG as `size_t *', and store there the TLS module ID 161 of this object's PT_TLS segment, as used in TLS relocations; 162 store zero if this object does not define a PT_TLS segment. */ 163 RTLD_DI_TLS_MODID = 9, 164 165 /* Treat ARG as `void **', and store there a pointer to the calling 166 thread's TLS block corresponding to this object's PT_TLS segment. 167 Store a null pointer if this object does not define a PT_TLS 168 segment, or if the calling thread has not allocated a block for it. */ 169 RTLD_DI_TLS_DATA = 10, 170 171 RTLD_DI_MAX = 10 172 }; 173 174 175 /* This is the type of elements in `Dl_serinfo', below. 176 The `dls_name' member points to space in the buffer passed to `dlinfo'. */ 177 typedef struct 178 { 179 char *dls_name; /* Name of library search path directory. */ 180 unsigned int dls_flags; /* Indicates where this directory came from. */ 181 } Dl_serpath; 182 183 /* This is the structure that must be passed (by reference) to `dlinfo' for 184 the RTLD_DI_SERINFO and RTLD_DI_SERINFOSIZE requests. */ 185 typedef struct 186 { 187 size_t dls_size; /* Size in bytes of the whole buffer. */ 188 unsigned int dls_cnt; /* Number of elements in `dls_serpath'. */ 189 Dl_serpath dls_serpath[1]; /* Actually longer, dls_cnt elements. */ 190 } Dl_serinfo; 191 #endif 192 #endif /* __USE_GNU */ 193 194 195 __END_DECLS 196 197 #endif /* dlfcn.h */ 198