1 /*
2 * xmlmodule.c : basic API for dynamic module loading added 2.6.17
3 *
4 * See Copyright for the status of this software.
5 *
6 * [email protected]
7 *
8 * http://www.fortran-2000.com/ArnaudRecipes/sharedlib.html
9 */
10
11 /* In order RTLD_GLOBAL and RTLD_NOW to be defined on zOS */
12 #if defined(__MVS__)
13 #define _UNIX03_SOURCE
14 #endif
15
16 #define IN_LIBXML
17 #include "libxml.h"
18
19 #include <string.h>
20 #include <libxml/xmlmodule.h>
21 #include <libxml/xmlmemory.h>
22 #include <libxml/xmlerror.h>
23 #include <libxml/xmlstring.h>
24
25 #include "private/error.h"
26
27 #ifdef LIBXML_MODULES_ENABLED
28
29 struct _xmlModule {
30 unsigned char *name;
31 void *handle;
32 };
33
34 static void *xmlModulePlatformOpen(const char *name);
35 static int xmlModulePlatformClose(void *handle);
36 static int xmlModulePlatformSymbol(void *handle, const char *name, void **result);
37
38 /************************************************************************
39 * *
40 * module memory error handler *
41 * *
42 ************************************************************************/
43
44 /**
45 * xmlModuleOpen:
46 * @name: the module name
47 * @options: a set of xmlModuleOption
48 *
49 * Opens a module/shared library given its name or path
50 * NOTE: that due to portability issues, behaviour can only be
51 * guaranteed with @name using ASCII. We cannot guarantee that
52 * an UTF-8 string would work, which is why name is a const char *
53 * and not a const xmlChar * .
54 * TODO: options are not yet implemented.
55 *
56 * Returns a handle for the module or NULL in case of error
57 */
58 xmlModulePtr
xmlModuleOpen(const char * name,int options ATTRIBUTE_UNUSED)59 xmlModuleOpen(const char *name, int options ATTRIBUTE_UNUSED)
60 {
61 xmlModulePtr module;
62
63 module = (xmlModulePtr) xmlMalloc(sizeof(xmlModule));
64 if (module == NULL)
65 return (NULL);
66
67 memset(module, 0, sizeof(xmlModule));
68
69 module->handle = xmlModulePlatformOpen(name);
70
71 if (module->handle == NULL) {
72 xmlFree(module);
73 return(NULL);
74 }
75
76 module->name = xmlStrdup((const xmlChar *) name);
77 return (module);
78 }
79
80 /**
81 * xmlModuleSymbol:
82 * @module: the module
83 * @name: the name of the symbol
84 * @symbol: the resulting symbol address
85 *
86 * Lookup for a symbol address in the given module
87 * NOTE: that due to portability issues, behaviour can only be
88 * guaranteed with @name using ASCII. We cannot guarantee that
89 * an UTF-8 string would work, which is why name is a const char *
90 * and not a const xmlChar * .
91 *
92 * Returns 0 if the symbol was found, or -1 in case of error
93 */
94 int
xmlModuleSymbol(xmlModulePtr module,const char * name,void ** symbol)95 xmlModuleSymbol(xmlModulePtr module, const char *name, void **symbol)
96 {
97 int rc = -1;
98
99 if ((NULL == module) || (symbol == NULL) || (name == NULL))
100 return rc;
101
102 rc = xmlModulePlatformSymbol(module->handle, name, symbol);
103
104 if (rc == -1)
105 return rc;
106
107 return rc;
108 }
109
110 /**
111 * xmlModuleClose:
112 * @module: the module handle
113 *
114 * The close operations unload the associated module and free the
115 * data associated to the module.
116 *
117 * Returns 0 in case of success, -1 in case of argument error and -2
118 * if the module could not be closed/unloaded.
119 */
120 int
xmlModuleClose(xmlModulePtr module)121 xmlModuleClose(xmlModulePtr module)
122 {
123 int rc;
124
125 if (NULL == module)
126 return -1;
127
128 rc = xmlModulePlatformClose(module->handle);
129
130 if (rc != 0)
131 return -2;
132
133 rc = xmlModuleFree(module);
134 return (rc);
135 }
136
137 /**
138 * xmlModuleFree:
139 * @module: the module handle
140 *
141 * The free operations free the data associated to the module
142 * but does not unload the associated shared library which may still
143 * be in use.
144 *
145 * Returns 0 in case of success, -1 in case of argument error
146 */
147 int
xmlModuleFree(xmlModulePtr module)148 xmlModuleFree(xmlModulePtr module)
149 {
150 if (NULL == module)
151 return -1;
152
153 xmlFree(module->name);
154 xmlFree(module);
155
156 return (0);
157 }
158
159 #if defined(HAVE_DLOPEN) && !defined(_WIN32)
160 #include <dlfcn.h>
161
162 #ifndef RTLD_GLOBAL /* For Tru64 UNIX 4.0 */
163 #define RTLD_GLOBAL 0
164 #endif
165
166 /**
167 * xmlModulePlatformOpen:
168 * @name: path to the module
169 *
170 * returns a handle on success, and zero on error.
171 */
172
173 static void *
xmlModulePlatformOpen(const char * name)174 xmlModulePlatformOpen(const char *name)
175 {
176 return dlopen(name, RTLD_GLOBAL | RTLD_NOW);
177 }
178
179 /*
180 * xmlModulePlatformClose:
181 * @handle: handle to the module
182 *
183 * returns 0 on success, and non-zero on error.
184 */
185
186 static int
xmlModulePlatformClose(void * handle)187 xmlModulePlatformClose(void *handle)
188 {
189 return dlclose(handle);
190 }
191
192 /*
193 * xmlModulePlatformSymbol:
194 * http://www.opengroup.org/onlinepubs/009695399/functions/dlsym.html
195 * returns 0 on success and the loaded symbol in result, and -1 on error.
196 */
197
198 static int
xmlModulePlatformSymbol(void * handle,const char * name,void ** symbol)199 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
200 {
201 *symbol = dlsym(handle, name);
202 if (dlerror() != NULL) {
203 return -1;
204 }
205 return 0;
206 }
207
208 #else /* ! HAVE_DLOPEN */
209
210 #ifdef HAVE_SHLLOAD /* HAVE_SHLLOAD */
211 #include <dl.h>
212 /*
213 * xmlModulePlatformOpen:
214 * returns a handle on success, and zero on error.
215 */
216
217 static void *
xmlModulePlatformOpen(const char * name)218 xmlModulePlatformOpen(const char *name)
219 {
220 return shl_load(name, BIND_IMMEDIATE, 0L);
221 }
222
223 /*
224 * xmlModulePlatformClose:
225 * returns 0 on success, and non-zero on error.
226 */
227
228 static int
xmlModulePlatformClose(void * handle)229 xmlModulePlatformClose(void *handle)
230 {
231 return shl_unload(handle);
232 }
233
234 /*
235 * xmlModulePlatformSymbol:
236 * http://docs.hp.com/en/B2355-90683/shl_load.3X.html
237 * returns 0 on success and the loaded symbol in result, and -1 on error.
238 */
239
240 static int
xmlModulePlatformSymbol(void * handle,const char * name,void ** symbol)241 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
242 {
243 int rc;
244
245 errno = 0;
246 rc = shl_findsym(&handle, name, TYPE_UNDEFINED, symbol);
247 return rc;
248 }
249
250 #endif /* HAVE_SHLLOAD */
251 #endif /* ! HAVE_DLOPEN */
252
253 #if defined(_WIN32)
254
255 #define WIN32_LEAN_AND_MEAN
256 #include <windows.h>
257
258 /*
259 * xmlModulePlatformOpen:
260 * returns a handle on success, and zero on error.
261 */
262
263 static void *
xmlModulePlatformOpen(const char * name)264 xmlModulePlatformOpen(const char *name)
265 {
266 return LoadLibraryA(name);
267 }
268
269 /*
270 * xmlModulePlatformClose:
271 * returns 0 on success, and non-zero on error.
272 */
273
274 static int
xmlModulePlatformClose(void * handle)275 xmlModulePlatformClose(void *handle)
276 {
277 int rc;
278
279 rc = FreeLibrary(handle);
280 return (0 == rc);
281 }
282
283 /*
284 * xmlModulePlatformSymbol:
285 * http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/getprocaddress.asp
286 * returns 0 on success and the loaded symbol in result, and -1 on error.
287 */
288
289 static int
xmlModulePlatformSymbol(void * handle,const char * name,void ** symbol)290 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
291 {
292 XML_IGNORE_FPTR_CAST_WARNINGS
293 *symbol = GetProcAddress(handle, name);
294 return (NULL == *symbol) ? -1 : 0;
295 XML_POP_WARNINGS
296 }
297
298 #endif /* _WIN32 */
299
300 #endif /* LIBXML_MODULES_ENABLED */
301