lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* User functions for run-time dynamic loading. |
| 2 | Copyright (C) 1995-1999,2000,2001,2003,2004,2006 |
| 3 | Free Software Foundation, Inc. |
| 4 | This file is part of the GNU C Library. |
| 5 | |
| 6 | The GNU C Library is free software; you can redistribute it and/or |
| 7 | modify it under the terms of the GNU Lesser General Public |
| 8 | License as published by the Free Software Foundation; either |
| 9 | version 2.1 of the License, or (at your option) any later version. |
| 10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | Lesser General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU Lesser General Public |
| 17 | License along with the GNU C Library; if not, write to the Free |
| 18 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 19 | 02111-1307 USA. */ |
| 20 | |
| 21 | #ifndef _DLFCN_H |
| 22 | #define _DLFCN_H 1 |
| 23 | |
| 24 | #include <features.h> |
| 25 | #define __need_size_t |
| 26 | #include <stddef.h> |
| 27 | |
| 28 | /* Collect various system dependent definitions and declarations. */ |
| 29 | #include <bits/dlfcn.h> |
| 30 | |
| 31 | |
| 32 | #ifdef __USE_GNU |
| 33 | /* If the first argument of `dlsym' or `dlvsym' is set to RTLD_NEXT |
| 34 | the run-time address of the symbol called NAME in the next shared |
| 35 | object is returned. The "next" relation is defined by the order |
| 36 | the shared objects were loaded. */ |
| 37 | # define RTLD_NEXT ((void *) -1l) |
| 38 | |
| 39 | /* If the first argument to `dlsym' or `dlvsym' is set to RTLD_DEFAULT |
| 40 | the run-time address of the symbol called NAME in the global scope |
| 41 | is returned. */ |
| 42 | # define RTLD_DEFAULT ((void *) 0) |
| 43 | |
| 44 | |
| 45 | # if 0 /* uClibc doesnt support this */ |
| 46 | /* Type for namespace indeces. */ |
| 47 | typedef long int Lmid_t; |
| 48 | |
| 49 | /* Special namespace ID values. */ |
| 50 | # define LM_ID_BASE 0 /* Initial namespace. */ |
| 51 | # define LM_ID_NEWLM -1 /* For dlmopen: request new namespace. */ |
| 52 | # endif |
| 53 | #endif |
| 54 | |
| 55 | __BEGIN_DECLS |
| 56 | |
| 57 | /* Open the shared object FILE and map it in; return a handle that can be |
| 58 | passed to `dlsym' to get symbol values from it. */ |
| 59 | extern void *dlopen (__const char *__file, int __mode) __THROW; |
| 60 | |
| 61 | /* Unmap and close a shared object opened by `dlopen'. |
| 62 | The handle cannot be used again after calling `dlclose'. */ |
| 63 | extern int dlclose (void *__handle) __THROW __nonnull ((1)); |
| 64 | |
| 65 | /* Find the run-time address in the shared object HANDLE refers to |
| 66 | of the symbol called NAME. */ |
| 67 | extern void *dlsym (void *__restrict __handle, |
| 68 | __const char *__restrict __name) __THROW __nonnull ((2)); |
| 69 | |
| 70 | #if 0 /*def __USE_GNU*/ |
| 71 | /* Like `dlopen', but request object to be allocated in a new namespace. */ |
| 72 | extern void *dlmopen (Lmid_t __nsid, __const char *__file, int __mode) __THROW; |
| 73 | |
| 74 | /* Find the run-time address in the shared object HANDLE refers to |
| 75 | of the symbol called NAME with VERSION. */ |
| 76 | extern void *dlvsym (void *__restrict __handle, |
| 77 | __const char *__restrict __name, |
| 78 | __const char *__restrict __version) |
| 79 | __THROW __nonnull ((2, 3)); |
| 80 | #endif |
| 81 | |
| 82 | /* When any of the above functions fails, call this function |
| 83 | to return a string describing the error. Each call resets |
| 84 | the error string so that a following call returns null. */ |
| 85 | extern char *dlerror (void) __THROW; |
| 86 | |
| 87 | |
| 88 | #ifdef __USE_GNU |
| 89 | /* Structure containing information about object searched using |
| 90 | `dladdr'. */ |
| 91 | typedef struct |
| 92 | { |
| 93 | __const char *dli_fname; /* File name of defining object. */ |
| 94 | void *dli_fbase; /* Load address of that object. */ |
| 95 | __const char *dli_sname; /* Name of nearest symbol. */ |
| 96 | void *dli_saddr; /* Exact value of nearest symbol. */ |
| 97 | } Dl_info; |
| 98 | |
| 99 | /* Fill in *INFO with the following information about ADDRESS. |
| 100 | Returns 0 iff no shared object's segments contain that address. */ |
| 101 | extern int dladdr (__const void *__address, Dl_info *__info) |
| 102 | __THROW __nonnull ((2)); |
| 103 | |
| 104 | #if 0 /* not supported by uClibc */ |
| 105 | /* Same as `dladdr', but additionally sets *EXTRA_INFO according to FLAGS. */ |
| 106 | extern int dladdr1 (__const void *__address, Dl_info *__info, |
| 107 | void **__extra_info, int __flags) __THROW __nonnull ((2)); |
| 108 | |
| 109 | /* These are the possible values for the FLAGS argument to `dladdr1'. |
| 110 | This indicates what extra information is stored at *EXTRA_INFO. |
| 111 | It may also be zero, in which case the EXTRA_INFO argument is not used. */ |
| 112 | enum |
| 113 | { |
| 114 | /* Matching symbol table entry (const ElfNN_Sym *). */ |
| 115 | RTLD_DL_SYMENT = 1, |
| 116 | |
| 117 | /* The object containing the address (struct link_map *). */ |
| 118 | RTLD_DL_LINKMAP = 2 |
| 119 | }; |
| 120 | |
| 121 | |
| 122 | /* Get information about the shared object HANDLE refers to. |
| 123 | REQUEST is from among the values below, and determines the use of ARG. |
| 124 | |
| 125 | On success, returns zero. On failure, returns -1 and records an error |
| 126 | message to be fetched with `dlerror'. */ |
| 127 | extern int dlinfo (void *__restrict __handle, |
| 128 | int __request, void *__restrict __arg) |
| 129 | __THROW __nonnull ((1, 3)); |
| 130 | |
| 131 | /* These are the possible values for the REQUEST argument to `dlinfo'. */ |
| 132 | enum |
| 133 | { |
| 134 | /* Treat ARG as `lmid_t *'; store namespace ID for HANDLE there. */ |
| 135 | RTLD_DI_LMID = 1, |
| 136 | |
| 137 | /* Treat ARG as `struct link_map **'; |
| 138 | store the `struct link_map *' for HANDLE there. */ |
| 139 | RTLD_DI_LINKMAP = 2, |
| 140 | |
| 141 | RTLD_DI_CONFIGADDR = 3, /* Unsupported, defined by Solaris. */ |
| 142 | |
| 143 | /* Treat ARG as `Dl_serinfo *' (see below), and fill in to describe the |
| 144 | directories that will be searched for dependencies of this object. |
| 145 | RTLD_DI_SERINFOSIZE fills in just the `dls_cnt' and `dls_size' |
| 146 | entries to indicate the size of the buffer that must be passed to |
| 147 | RTLD_DI_SERINFO to fill in the full information. */ |
| 148 | RTLD_DI_SERINFO = 4, |
| 149 | RTLD_DI_SERINFOSIZE = 5, |
| 150 | |
| 151 | /* Treat ARG as `char *', and store there the directory name used to |
| 152 | expand $ORIGIN in this shared object's dependency file names. */ |
| 153 | RTLD_DI_ORIGIN = 6, |
| 154 | |
| 155 | RTLD_DI_PROFILENAME = 7, /* Unsupported, defined by Solaris. */ |
| 156 | RTLD_DI_PROFILEOUT = 8, /* Unsupported, defined by Solaris. */ |
| 157 | |
| 158 | /* Treat ARG as `size_t *', and store there the TLS module ID |
| 159 | of this object's PT_TLS segment, as used in TLS relocations; |
| 160 | store zero if this object does not define a PT_TLS segment. */ |
| 161 | RTLD_DI_TLS_MODID = 9, |
| 162 | |
| 163 | /* Treat ARG as `void **', and store there a pointer to the calling |
| 164 | thread's TLS block corresponding to this object's PT_TLS segment. |
| 165 | Store a null pointer if this object does not define a PT_TLS |
| 166 | segment, or if the calling thread has not allocated a block for it. */ |
| 167 | RTLD_DI_TLS_DATA = 10, |
| 168 | |
| 169 | RTLD_DI_MAX = 10, |
| 170 | }; |
| 171 | |
| 172 | |
| 173 | /* This is the type of elements in `Dl_serinfo', below. |
| 174 | The `dls_name' member points to space in the buffer passed to `dlinfo'. */ |
| 175 | typedef struct |
| 176 | { |
| 177 | char *dls_name; /* Name of library search path directory. */ |
| 178 | unsigned int dls_flags; /* Indicates where this directory came from. */ |
| 179 | } Dl_serpath; |
| 180 | |
| 181 | /* This is the structure that must be passed (by reference) to `dlinfo' for |
| 182 | the RTLD_DI_SERINFO and RTLD_DI_SERINFOSIZE requests. */ |
| 183 | typedef struct |
| 184 | { |
| 185 | size_t dls_size; /* Size in bytes of the whole buffer. */ |
| 186 | unsigned int dls_cnt; /* Number of elements in `dls_serpath'. */ |
| 187 | Dl_serpath dls_serpath[1]; /* Actually longer, dls_cnt elements. */ |
| 188 | } Dl_serinfo; |
| 189 | |
| 190 | #else |
| 191 | |
| 192 | /* Get information about the shared objects currently loaded */ |
| 193 | extern int dlinfo (void); |
| 194 | |
| 195 | #endif |
| 196 | #endif /* __USE_GNU */ |
| 197 | |
| 198 | |
| 199 | __END_DECLS |
| 200 | |
| 201 | #endif /* dlfcn.h */ |