aboutsummaryrefslogtreecommitdiff
path: root/libltdl/ltdl.h
blob: 2e2465158cefbaf8d1819a157dc74661d0826809 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
/* ltdl.h -- generic dlopen functions
   Copyright (C) 1998-2000 Free Software Foundation, Inc.
   Originally by Thomas Tanner <tanner@ffii.org>
   This file is part of GNU Libtool.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.

As a special exception to the GNU Lesser General Public License,
if you distribute this file as part of a program or library that
is built using GNU libtool, you may include it under the same
distribution terms that you use for the rest of that program.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307  USA
*/

/* Only include this header file once. */
#ifndef LTDL_H
#define LTDL_H 1

#include <sys/types.h>          /* for size_t declaration */


/* --- MACROS FOR PORTABILITY --- */


/* Saves on those hard to debug '\0' typos....  */
#define LT_EOS_CHAR	'\0'

/* LTDL_BEGIN_C_DECLS should be used at the beginning of your declarations,
   so that C++ compilers don't mangle their names.  Use LTDL_END_C_DECLS at
   the end of C declarations. */
#ifdef __cplusplus
# define LT_BEGIN_C_DECLS	extern "C" {
# define LT_END_C_DECLS		}
#else
# define LT_BEGIN_C_DECLS       /* empty */
# define LT_END_C_DECLS         /* empty */
#endif

LT_BEGIN_C_DECLS
/* LT_PARAMS is a macro used to wrap function prototypes, so that compilers
   that don't understand ANSI C prototypes still work, and ANSI C
   compilers can issue warnings about type mismatches.  */
#if defined (__STDC__) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(WIN32) || defined(__cplusplus)
# define LT_PARAMS(protos)	protos
# define lt_ptr		void*
#else
# define LT_PARAMS(protos)	()
# define lt_ptr		char*
#endif
/* LT_STMT_START/END are used to create macros which expand to a
   a single compound statement in a portable way.  */
#if defined (__GNUC__) && !defined (__STRICT_ANSI__) && !defined (__cplusplus)
#  define LT_STMT_START        (void)(
#  define LT_STMT_END          )
#else
#  if (defined (sun) || defined (__sun__))
#    define LT_STMT_START      if (1)
#    define LT_STMT_END        else (void)0
#  else
#    define LT_STMT_START      do
#    define LT_STMT_END        while (0)
#  endif
#endif
/* LT_CONC creates a new concatenated symbol for the compiler
   in a portable way.  */
#if defined(__STDC__) || defined(__cplusplus) || defined(_MSC_VER)
#  define LT_CONC(s,t)	s##t
#else
#  define LT_CONC(s,t)	s/**/t
#endif
/* LT_STRLEN can be used safely on NULL pointers.  */
#define LT_STRLEN(s)	(((s) && (s)[0]) ? strlen (s) : 0)
/* --- WINDOWS SUPPORT --- */
/* Canonicalise Windows and Cygwin recognition macros.  */
#ifdef __CYGWIN32__
#  ifndef __CYGWIN__
#    define __CYGWIN__ __CYGWIN32__
#  endif
#endif
#if defined(_WIN32) || defined(WIN32)
#  ifndef __WINDOWS__
#    ifdef _WIN32
#      define __WINDOWS__ _WIN32
#    else
#      ifdef WIN32
#        define __WINDOWS__ WIN32
#      endif
#    endif
#  endif
#endif
#ifdef __WINDOWS__
#  ifndef __CYGWIN__
/* LT_DIRSEP_CHAR is accepted *in addition* to '/' as a directory
   separator when it is set. */
#    define LT_DIRSEP_CHAR	'\\'
#    define LT_PATHSEP_CHAR	';'
#  endif
#endif
#ifndef LT_PATHSEP_CHAR
#  define LT_PATHSEP_CHAR	':'
#endif
/* DLL building support on win32 hosts;  mostly to workaround their
   ridiculous implementation of data symbol exporting. */
#ifndef LT_SCOPE
#  ifdef __WINDOWS__
#    ifdef DLL_EXPORT           /* defined by libtool (if required) */
#      define LT_SCOPE	__declspec(dllexport)
#    endif
#    ifdef LIBLTDL_DLL_IMPORT   /* define if linking with this dll */
#      define LT_SCOPE	extern __declspec(dllimport)
#    endif
#  endif
#  ifndef LT_SCOPE              /* static linking or !__WINDOWS__ */
#    define LT_SCOPE	extern
#  endif
#endif
#if defined(_MSC_VER)           /* Visual Studio */
#  define R_OK 4
#endif
/* --- DYNAMIC MODULE LOADING API --- */
typedef struct lt_dlhandle_struct *lt_dlhandle; /* A loaded module.  */

/* Initialisation and finalisation functions for libltdl. */
LT_SCOPE int lt_dlinit LT_PARAMS ((void));
LT_SCOPE int lt_dlexit LT_PARAMS ((void));

/* Module search path manipulation.  */
LT_SCOPE int lt_dladdsearchdir LT_PARAMS ((const char *search_dir));
LT_SCOPE int lt_dlinsertsearchdir LT_PARAMS ((const char *before,
                                              const char *search_dir));
LT_SCOPE int lt_dlsetsearchpath LT_PARAMS ((const char *search_path));
LT_SCOPE const char *lt_dlgetsearchpath LT_PARAMS ((void));
LT_SCOPE int lt_dlforeachfile LT_PARAMS ((const char *search_path,
                                          int (*func) (const char *filename,
                                                       lt_ptr data),
                                          lt_ptr data));

/* Portable libltdl versions of the system dlopen() API. */
LT_SCOPE lt_dlhandle lt_dlopen LT_PARAMS ((const char *filename));
LT_SCOPE lt_dlhandle lt_dlopenext LT_PARAMS ((const char *filename));
LT_SCOPE lt_ptr lt_dlsym LT_PARAMS ((lt_dlhandle handle, const char *name));
LT_SCOPE const char *lt_dlerror LT_PARAMS ((void));
LT_SCOPE int lt_dlclose LT_PARAMS ((lt_dlhandle handle));

/* Module residency management. */
LT_SCOPE int lt_dlmakeresident LT_PARAMS ((lt_dlhandle handle));
LT_SCOPE int lt_dlisresident LT_PARAMS ((lt_dlhandle handle));




/* --- MUTEX LOCKING --- */


typedef void lt_dlmutex_lock LT_PARAMS ((void));
typedef void lt_dlmutex_unlock LT_PARAMS ((void));
typedef void lt_dlmutex_seterror LT_PARAMS ((const char *errmsg));
typedef const char *lt_dlmutex_geterror LT_PARAMS ((void));

LT_SCOPE int lt_dlmutex_register LT_PARAMS ((lt_dlmutex_lock * lock,
                                             lt_dlmutex_unlock * unlock,
                                             lt_dlmutex_seterror * seterror,
                                             lt_dlmutex_geterror * geterror));




/* --- MEMORY HANDLING --- */


/* By default, the realloc function pointer is set to our internal
   realloc implementation which iself uses lt_dlmalloc and lt_dlfree.
   libltdl relies on a featureful realloc, but if you are sure yours
   has the right semantics then you can assign it directly.  Generally,
   it is safe to assign just a malloc() and a free() function.  */
LT_SCOPE
lt_ptr (*lt_dlmalloc)
LT_PARAMS ((size_t size));
     LT_SCOPE lt_ptr (*lt_dlrealloc) LT_PARAMS ((lt_ptr ptr, size_t size));
     LT_SCOPE void (*lt_dlfree) LT_PARAMS ((lt_ptr ptr));




/* --- PRELOADED MODULE SUPPORT --- */


/* A preopened symbol. Arrays of this type comprise the exported
   symbols for a dlpreopened module. */
     typedef struct
     {
       const char *name;
       lt_ptr address;
     } lt_dlsymlist;

     LT_SCOPE int lt_dlpreload LT_PARAMS ((const lt_dlsymlist * preloaded));
     LT_SCOPE int lt_dlpreload_default
       LT_PARAMS ((const lt_dlsymlist * preloaded));

#define LTDL_SET_PRELOADED_SYMBOLS() 		LT_STMT_START{	\
	extern const lt_dlsymlist lt_preloaded_symbols[];		\
	lt_dlpreload_default(lt_preloaded_symbols);			\
						}LT_STMT_END




/* --- MODULE INFORMATION --- */


/* Read only information pertaining to a loaded module. */
     typedef struct
     {
       char *filename;          /* file name */
       char *name;              /* module name */
       int ref_count;           /* number of times lt_dlopened minus
                                   number of times lt_dlclosed. */
     } lt_dlinfo;

     LT_SCOPE const lt_dlinfo *lt_dlgetinfo LT_PARAMS ((lt_dlhandle handle));
     LT_SCOPE lt_dlhandle lt_dlhandle_next LT_PARAMS ((lt_dlhandle place));
     LT_SCOPE int lt_dlforeach
       LT_PARAMS ((int (*func) (lt_dlhandle handle, lt_ptr data),
                   lt_ptr data));

/* Associating user data with loaded modules. */
     typedef unsigned lt_dlcaller_id;

     LT_SCOPE lt_dlcaller_id lt_dlcaller_register LT_PARAMS ((void));
     LT_SCOPE lt_ptr lt_dlcaller_set_data LT_PARAMS ((lt_dlcaller_id key,
                                                      lt_dlhandle handle,
                                                      lt_ptr data));
     LT_SCOPE lt_ptr lt_dlcaller_get_data LT_PARAMS ((lt_dlcaller_id key,
                                                      lt_dlhandle handle));



/* --- USER MODULE LOADER API --- */


     typedef struct lt_dlloader lt_dlloader;
     typedef lt_ptr lt_user_data;
     typedef lt_ptr lt_module;

/* Function pointer types for creating user defined module loaders. */
     typedef lt_module lt_module_open LT_PARAMS ((lt_user_data loader_data,
                                                  const char *filename));
     typedef int lt_module_close LT_PARAMS ((lt_user_data loader_data,
                                             lt_module handle));
     typedef lt_ptr lt_find_sym LT_PARAMS ((lt_user_data loader_data,
                                            lt_module handle,
                                            const char *symbol));
     typedef int lt_dlloader_exit LT_PARAMS ((lt_user_data loader_data));

     struct lt_user_dlloader
     {
       const char *sym_prefix;
       lt_module_open *module_open;
       lt_module_close *module_close;
       lt_find_sym *find_sym;
       lt_dlloader_exit *dlloader_exit;
       lt_user_data dlloader_data;
     };

     LT_SCOPE lt_dlloader *lt_dlloader_next LT_PARAMS ((lt_dlloader * place));
     LT_SCOPE lt_dlloader *lt_dlloader_find
       LT_PARAMS ((const char *loader_name));
     LT_SCOPE const char *lt_dlloader_name LT_PARAMS ((lt_dlloader * place));
     LT_SCOPE lt_user_data *lt_dlloader_data
       LT_PARAMS ((lt_dlloader * place));
     LT_SCOPE int lt_dlloader_add
       LT_PARAMS ((lt_dlloader * place,
                   const struct lt_user_dlloader * dlloader,
                   const char *loader_name));
     LT_SCOPE int lt_dlloader_remove LT_PARAMS ((const char *loader_name));



/* --- ERROR MESSAGE HANDLING --- */


/* Defining error strings alongside their symbolic names in a macro in
   this way allows us to expand the macro in different contexts with
   confidence that the enumeration of symbolic names will map correctly
   onto the table of error strings.  */
#define lt_dlerror_table						\
    LT_ERROR(UNKNOWN,		    "unknown error")			\
    LT_ERROR(DLOPEN_NOT_SUPPORTED,  "dlopen support not available")	\
    LT_ERROR(INVALID_LOADER,	    "invalid loader")			\
    LT_ERROR(INIT_LOADER,	    "loader initialization failed")	\
    LT_ERROR(REMOVE_LOADER,	    "loader removal failed")		\
    LT_ERROR(FILE_NOT_FOUND,	    "file not found")			\
    LT_ERROR(DEPLIB_NOT_FOUND,      "dependency library not found")	\
    LT_ERROR(NO_SYMBOLS,	    "no symbols defined")		\
    LT_ERROR(CANNOT_OPEN,	    "can't open the module")		\
    LT_ERROR(CANNOT_CLOSE,	    "can't close the module")		\
    LT_ERROR(SYMBOL_NOT_FOUND,      "symbol not found")			\
    LT_ERROR(NO_MEMORY,		    "not enough memory")		\
    LT_ERROR(INVALID_HANDLE,	    "invalid module handle")		\
    LT_ERROR(BUFFER_OVERFLOW,	    "internal buffer overflow")		\
    LT_ERROR(INVALID_ERRORCODE,     "invalid errorcode")		\
    LT_ERROR(SHUTDOWN,		    "library already shutdown")		\
    LT_ERROR(CLOSE_RESIDENT_MODULE, "can't close resident module")	\
    LT_ERROR(INVALID_MUTEX_ARGS,    "invalid mutex handler registration") \
    LT_ERROR(INVALID_POSITION,	    "invalid search path insert position")

/* Enumerate the symbolic error names. */
     enum
     {
#define LT_ERROR(name, diagnostic)	LT_CONC(LT_ERROR_, name),
       lt_dlerror_table
#undef LT_ERROR
       LT_ERROR_MAX
     };

/* These functions are only useful from inside custom module loaders. */
     LT_SCOPE int lt_dladderror LT_PARAMS ((const char *diagnostic));
     LT_SCOPE int lt_dlseterror LT_PARAMS ((int errorcode));




/* --- SOURCE COMPATIBILITY WITH OLD LIBLTDL --- */


#ifdef LT_NON_POSIX_NAMESPACE
#  define lt_ptr_t		lt_ptr
#  define lt_module_t		lt_module
#  define lt_module_open_t	lt_module_open
#  define lt_module_close_t	lt_module_close
#  define lt_find_sym_t		lt_find_sym
#  define lt_dlloader_exit_t	lt_dlloader_exit
#  define lt_dlloader_t		lt_dlloader
#  define lt_dlloader_data_t	lt_user_data
#endif

LT_END_C_DECLS
#endif /* !LTDL_H */