d9898ee8 |
1 | /* ltdl.h -- generic dlopen functions |
2 | Copyright (C) 1998-2000 Free Software Foundation, Inc. |
3 | Originally by Thomas Tanner <tanner@ffii.org> |
4 | This file is part of GNU Libtool. |
5 | |
6 | This 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 of the License, or (at your option) any later version. |
10 | |
11 | As a special exception to the GNU Lesser General Public License, |
12 | if you distribute this file as part of a program or library that |
13 | is built using GNU libtool, you may include it under the same |
14 | distribution terms that you use for the rest of that program. |
15 | |
16 | This library is distributed in the hope that it will be useful, |
17 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
19 | Lesser General Public License for more details. |
20 | |
21 | You should have received a copy of the GNU Lesser General Public |
22 | License along with this library; if not, write to the Free |
23 | Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
24 | 02110-1301 USA |
25 | */ |
26 | |
27 | /* Only include this header file once. */ |
28 | #ifndef LTDL_H |
29 | #define LTDL_H 1 |
30 | |
31 | #include <sys/types.h> /* for size_t declaration */ |
32 | |
33 | \f |
34 | /* --- MACROS FOR PORTABILITY --- */ |
35 | |
36 | |
37 | /* Saves on those hard to debug '\0' typos.... */ |
38 | #define LT_EOS_CHAR '\0' |
39 | |
40 | /* LTDL_BEGIN_C_DECLS should be used at the beginning of your declarations, |
41 | so that C++ compilers don't mangle their names. Use LTDL_END_C_DECLS at |
42 | the end of C declarations. */ |
43 | #ifdef __cplusplus |
44 | # define LT_BEGIN_C_DECLS extern "C" { |
45 | # define LT_END_C_DECLS } |
46 | #else |
47 | # define LT_BEGIN_C_DECLS /* empty */ |
48 | # define LT_END_C_DECLS /* empty */ |
49 | #endif |
50 | |
51 | LT_BEGIN_C_DECLS |
52 | |
53 | |
54 | /* LT_PARAMS is a macro used to wrap function prototypes, so that compilers |
55 | that don't understand ANSI C prototypes still work, and ANSI C |
56 | compilers can issue warnings about type mismatches. */ |
57 | #if defined (__STDC__) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(WIN32) || defined(__cplusplus) |
58 | # define LT_PARAMS(protos) protos |
59 | # define lt_ptr void* |
60 | #else |
61 | # define LT_PARAMS(protos) () |
62 | # define lt_ptr char* |
63 | #endif |
64 | |
65 | /* LT_STMT_START/END are used to create macros which expand to a |
66 | a single compound statement in a portable way. */ |
67 | #if defined (__GNUC__) && !defined (__STRICT_ANSI__) && !defined (__cplusplus) |
68 | # define LT_STMT_START (void)( |
69 | # define LT_STMT_END ) |
70 | #else |
71 | # if (defined (sun) || defined (__sun__)) |
72 | # define LT_STMT_START if (1) |
73 | # define LT_STMT_END else (void)0 |
74 | # else |
75 | # define LT_STMT_START do |
76 | # define LT_STMT_END while (0) |
77 | # endif |
78 | #endif |
79 | |
80 | /* LT_CONC creates a new concatenated symbol for the compiler |
81 | in a portable way. */ |
82 | #if defined(__STDC__) || defined(__cplusplus) || defined(_MSC_VER) |
83 | # define LT_CONC(s,t) s##t |
84 | #else |
85 | # define LT_CONC(s,t) s/**/t |
86 | #endif |
87 | |
88 | /* LT_STRLEN can be used safely on NULL pointers. */ |
89 | #define LT_STRLEN(s) (((s) && (s)[0]) ? strlen (s) : 0) |
90 | |
91 | |
92 | \f |
93 | /* --- WINDOWS SUPPORT --- */ |
94 | |
95 | |
96 | /* Canonicalise Windows and Cygwin recognition macros. */ |
97 | #ifdef __CYGWIN32__ |
98 | # ifndef __CYGWIN__ |
99 | # define __CYGWIN__ __CYGWIN32__ |
100 | # endif |
101 | #endif |
102 | #if defined(_WIN32) || defined(WIN32) |
103 | # ifndef __WINDOWS__ |
104 | # ifdef _WIN32 |
105 | # define __WINDOWS__ _WIN32 |
106 | # else |
107 | # ifdef WIN32 |
108 | # define __WINDOWS__ WIN32 |
109 | # endif |
110 | # endif |
111 | # endif |
112 | #endif |
113 | |
114 | |
115 | #ifdef __WINDOWS__ |
116 | # ifndef __CYGWIN__ |
117 | /* LT_DIRSEP_CHAR is accepted *in addition* to '/' as a directory |
118 | separator when it is set. */ |
119 | # define LT_DIRSEP_CHAR '\\' |
120 | # define LT_PATHSEP_CHAR ';' |
121 | # endif |
122 | #endif |
123 | #ifndef LT_PATHSEP_CHAR |
124 | # define LT_PATHSEP_CHAR ':' |
125 | #endif |
126 | |
127 | /* DLL building support on win32 hosts; mostly to workaround their |
128 | ridiculous implementation of data symbol exporting. */ |
129 | #ifndef LT_SCOPE |
130 | # ifdef __WINDOWS__ |
131 | # ifdef DLL_EXPORT /* defined by libtool (if required) */ |
132 | # define LT_SCOPE __declspec(dllexport) |
133 | # endif |
134 | # ifdef LIBLTDL_DLL_IMPORT /* define if linking with this dll */ |
135 | # define LT_SCOPE extern __declspec(dllimport) |
136 | # endif |
137 | # endif |
138 | # ifndef LT_SCOPE /* static linking or !__WINDOWS__ */ |
139 | # define LT_SCOPE extern |
140 | # endif |
141 | #endif |
142 | |
143 | |
144 | #if defined(_MSC_VER) /* Visual Studio */ |
145 | # define R_OK 4 |
146 | #endif |
147 | |
148 | |
149 | \f |
150 | /* --- DYNAMIC MODULE LOADING API --- */ |
151 | |
152 | |
153 | typedef struct lt_dlhandle_struct *lt_dlhandle; /* A loaded module. */ |
154 | |
155 | /* Initialisation and finalisation functions for libltdl. */ |
156 | LT_SCOPE int lt_dlinit LT_PARAMS((void)); |
157 | LT_SCOPE int lt_dlexit LT_PARAMS((void)); |
158 | |
159 | /* Module search path manipulation. */ |
160 | LT_SCOPE int lt_dladdsearchdir LT_PARAMS((const char *search_dir)); |
161 | LT_SCOPE int lt_dlinsertsearchdir LT_PARAMS((const char *before, |
162 | const char *search_dir)); |
163 | LT_SCOPE int lt_dlsetsearchpath LT_PARAMS((const char *search_path)); |
164 | LT_SCOPE const char *lt_dlgetsearchpath LT_PARAMS((void)); |
165 | LT_SCOPE int lt_dlforeachfile LT_PARAMS(( |
166 | const char *search_path, |
167 | int (*func) (const char *filename, lt_ptr data), |
168 | lt_ptr data)); |
169 | |
170 | /* Portable libltdl versions of the system dlopen() API. */ |
171 | LT_SCOPE lt_dlhandle lt_dlopen LT_PARAMS((const char *filename)); |
172 | LT_SCOPE lt_dlhandle lt_dlopenext LT_PARAMS((const char *filename)); |
173 | LT_SCOPE lt_ptr lt_dlsym LT_PARAMS((lt_dlhandle handle, |
174 | const char *name)); |
175 | LT_SCOPE const char *lt_dlerror LT_PARAMS((void)); |
176 | LT_SCOPE int lt_dlclose LT_PARAMS((lt_dlhandle handle)); |
177 | |
178 | /* Module residency management. */ |
179 | LT_SCOPE int lt_dlmakeresident LT_PARAMS((lt_dlhandle handle)); |
180 | LT_SCOPE int lt_dlisresident LT_PARAMS((lt_dlhandle handle)); |
181 | |
182 | |
183 | |
184 | \f |
185 | /* --- MUTEX LOCKING --- */ |
186 | |
187 | |
188 | typedef void lt_dlmutex_lock LT_PARAMS((void)); |
189 | typedef void lt_dlmutex_unlock LT_PARAMS((void)); |
190 | typedef void lt_dlmutex_seterror LT_PARAMS((const char *errmsg)); |
191 | typedef const char *lt_dlmutex_geterror LT_PARAMS((void)); |
192 | |
193 | LT_SCOPE int lt_dlmutex_register LT_PARAMS((lt_dlmutex_lock *lock, |
194 | lt_dlmutex_unlock *unlock, |
195 | lt_dlmutex_seterror *seterror, |
196 | lt_dlmutex_geterror *geterror)); |
197 | |
198 | |
199 | |
200 | \f |
201 | /* --- MEMORY HANDLING --- */ |
202 | |
203 | |
204 | /* By default, the realloc function pointer is set to our internal |
205 | realloc implementation which iself uses lt_dlmalloc and lt_dlfree. |
206 | libltdl relies on a featureful realloc, but if you are sure yours |
207 | has the right semantics then you can assign it directly. Generally, |
208 | it is safe to assign just a malloc() and a free() function. */ |
209 | LT_SCOPE lt_ptr (*lt_dlmalloc) LT_PARAMS((size_t size)); |
210 | LT_SCOPE lt_ptr (*lt_dlrealloc) LT_PARAMS((lt_ptr ptr, size_t size)); |
211 | LT_SCOPE void (*lt_dlfree) LT_PARAMS((lt_ptr ptr)); |
212 | |
213 | |
214 | |
215 | \f |
216 | /* --- PRELOADED MODULE SUPPORT --- */ |
217 | |
218 | |
219 | /* A preopened symbol. Arrays of this type comprise the exported |
220 | symbols for a dlpreopened module. */ |
221 | typedef struct { |
222 | const char *name; |
223 | lt_ptr address; |
224 | } lt_dlsymlist; |
225 | |
226 | LT_SCOPE int lt_dlpreload LT_PARAMS((const lt_dlsymlist *preloaded)); |
227 | LT_SCOPE int lt_dlpreload_default |
228 | LT_PARAMS((const lt_dlsymlist *preloaded)); |
229 | |
230 | #define LTDL_SET_PRELOADED_SYMBOLS() LT_STMT_START{ \ |
231 | extern const lt_dlsymlist lt_preloaded_symbols[]; \ |
232 | lt_dlpreload_default(lt_preloaded_symbols); \ |
233 | }LT_STMT_END |
234 | |
235 | |
236 | |
237 | \f |
238 | /* --- MODULE INFORMATION --- */ |
239 | |
240 | |
241 | /* Read only information pertaining to a loaded module. */ |
242 | typedef struct { |
243 | char *filename; /* file name */ |
244 | char *name; /* module name */ |
245 | int ref_count; /* number of times lt_dlopened minus |
246 | number of times lt_dlclosed. */ |
247 | } lt_dlinfo; |
248 | |
249 | LT_SCOPE const lt_dlinfo *lt_dlgetinfo LT_PARAMS((lt_dlhandle handle)); |
250 | LT_SCOPE lt_dlhandle lt_dlhandle_next LT_PARAMS((lt_dlhandle place)); |
251 | LT_SCOPE int lt_dlforeach LT_PARAMS(( |
252 | int (*func) (lt_dlhandle handle, lt_ptr data), |
253 | lt_ptr data)); |
254 | |
255 | /* Associating user data with loaded modules. */ |
256 | typedef unsigned lt_dlcaller_id; |
257 | |
258 | LT_SCOPE lt_dlcaller_id lt_dlcaller_register LT_PARAMS((void)); |
259 | LT_SCOPE lt_ptr lt_dlcaller_set_data LT_PARAMS((lt_dlcaller_id key, |
260 | lt_dlhandle handle, |
261 | lt_ptr data)); |
262 | LT_SCOPE lt_ptr lt_dlcaller_get_data LT_PARAMS((lt_dlcaller_id key, |
263 | lt_dlhandle handle)); |
264 | |
265 | |
266 | \f |
267 | /* --- USER MODULE LOADER API --- */ |
268 | |
269 | |
270 | typedef struct lt_dlloader lt_dlloader; |
271 | typedef lt_ptr lt_user_data; |
272 | typedef lt_ptr lt_module; |
273 | |
274 | /* Function pointer types for creating user defined module loaders. */ |
275 | typedef lt_module lt_module_open LT_PARAMS((lt_user_data loader_data, |
276 | const char *filename)); |
277 | typedef int lt_module_close LT_PARAMS((lt_user_data loader_data, |
278 | lt_module handle)); |
279 | typedef lt_ptr lt_find_sym LT_PARAMS((lt_user_data loader_data, |
280 | lt_module handle, |
281 | const char *symbol)); |
282 | typedef int lt_dlloader_exit LT_PARAMS((lt_user_data loader_data)); |
283 | |
284 | struct lt_user_dlloader { |
285 | const char *sym_prefix; |
286 | lt_module_open *module_open; |
287 | lt_module_close *module_close; |
288 | lt_find_sym *find_sym; |
289 | lt_dlloader_exit *dlloader_exit; |
290 | lt_user_data dlloader_data; |
291 | }; |
292 | |
293 | LT_SCOPE lt_dlloader *lt_dlloader_next LT_PARAMS((lt_dlloader *place)); |
294 | LT_SCOPE lt_dlloader *lt_dlloader_find LT_PARAMS(( |
295 | const char *loader_name)); |
296 | LT_SCOPE const char *lt_dlloader_name LT_PARAMS((lt_dlloader *place)); |
297 | LT_SCOPE lt_user_data *lt_dlloader_data LT_PARAMS((lt_dlloader *place)); |
298 | LT_SCOPE int lt_dlloader_add LT_PARAMS((lt_dlloader *place, |
299 | const struct lt_user_dlloader *dlloader, |
300 | const char *loader_name)); |
301 | LT_SCOPE int lt_dlloader_remove LT_PARAMS(( |
302 | const char *loader_name)); |
303 | |
304 | |
305 | \f |
306 | /* --- ERROR MESSAGE HANDLING --- */ |
307 | |
308 | |
309 | /* Defining error strings alongside their symbolic names in a macro in |
310 | this way allows us to expand the macro in different contexts with |
311 | confidence that the enumeration of symbolic names will map correctly |
312 | onto the table of error strings. */ |
313 | #define lt_dlerror_table \ |
314 | LT_ERROR(UNKNOWN, "unknown error") \ |
315 | LT_ERROR(DLOPEN_NOT_SUPPORTED, "dlopen support not available") \ |
316 | LT_ERROR(INVALID_LOADER, "invalid loader") \ |
317 | LT_ERROR(INIT_LOADER, "loader initialization failed") \ |
318 | LT_ERROR(REMOVE_LOADER, "loader removal failed") \ |
319 | LT_ERROR(FILE_NOT_FOUND, "file not found") \ |
320 | LT_ERROR(DEPLIB_NOT_FOUND, "dependency library not found") \ |
321 | LT_ERROR(NO_SYMBOLS, "no symbols defined") \ |
322 | LT_ERROR(CANNOT_OPEN, "can't open the module") \ |
323 | LT_ERROR(CANNOT_CLOSE, "can't close the module") \ |
324 | LT_ERROR(SYMBOL_NOT_FOUND, "symbol not found") \ |
325 | LT_ERROR(NO_MEMORY, "not enough memory") \ |
326 | LT_ERROR(INVALID_HANDLE, "invalid module handle") \ |
327 | LT_ERROR(BUFFER_OVERFLOW, "internal buffer overflow") \ |
328 | LT_ERROR(INVALID_ERRORCODE, "invalid errorcode") \ |
329 | LT_ERROR(SHUTDOWN, "library already shutdown") \ |
330 | LT_ERROR(CLOSE_RESIDENT_MODULE, "can't close resident module") \ |
331 | LT_ERROR(INVALID_MUTEX_ARGS, "invalid mutex handler registration") \ |
332 | LT_ERROR(INVALID_POSITION, "invalid search path insert position") |
333 | |
334 | /* Enumerate the symbolic error names. */ |
335 | enum { |
336 | #define LT_ERROR(name, diagnostic) LT_CONC(LT_ERROR_, name), |
337 | lt_dlerror_table |
338 | #undef LT_ERROR |
339 | |
340 | LT_ERROR_MAX |
341 | }; |
342 | |
343 | /* These functions are only useful from inside custom module loaders. */ |
344 | LT_SCOPE int lt_dladderror LT_PARAMS((const char *diagnostic)); |
345 | LT_SCOPE int lt_dlseterror LT_PARAMS((int errorcode)); |
346 | |
347 | |
348 | |
349 | \f |
350 | /* --- SOURCE COMPATIBILITY WITH OLD LIBLTDL --- */ |
351 | |
352 | |
353 | #ifdef LT_NON_POSIX_NAMESPACE |
354 | # define lt_ptr_t lt_ptr |
355 | # define lt_module_t lt_module |
356 | # define lt_module_open_t lt_module_open |
357 | # define lt_module_close_t lt_module_close |
358 | # define lt_find_sym_t lt_find_sym |
359 | # define lt_dlloader_exit_t lt_dlloader_exit |
360 | # define lt_dlloader_t lt_dlloader |
361 | # define lt_dlloader_data_t lt_user_data |
362 | #endif |
363 | |
364 | LT_END_C_DECLS |
365 | |
366 | #endif /* !LTDL_H */ |