1 /*
2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "memory/oopFactory.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "memory/universe.inline.hpp"
32 #include "oops/instanceKlass.hpp"
33 #include "oops/methodOop.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "oops/symbolOop.hpp"
36 #include "prims/jvm_misc.hpp"
37 #include "prims/nativeLookup.hpp"
38 #include "runtime/arguments.hpp"
39 #include "runtime/handles.inline.hpp"
40 #include "runtime/hpi.hpp"
41 #include "runtime/javaCalls.hpp"
42 #include "runtime/sharedRuntime.hpp"
43 #include "runtime/signature.hpp"
44 #ifdef TARGET_OS_FAMILY_linux
45 # include "os_linux.inline.hpp"
46 #endif
47 #ifdef TARGET_OS_FAMILY_solaris
48 # include "os_solaris.inline.hpp"
49 #endif
50 #ifdef TARGET_OS_FAMILY_windows
51 # include "os_windows.inline.hpp"
52 #endif
53
54
55 static void mangle_name_on(outputStream* st, symbolOop name, int begin, int end) {
56 char* bytes = (char*)name->bytes() + begin;
57 char* end_bytes = (char*)name->bytes() + end;
58 while (bytes < end_bytes) {
59 jchar c;
60 bytes = UTF8::next(bytes, &c);
61 if (c <= 0x7f && isalnum(c)) {
62 st->put((char) c);
63 } else {
64 if (c == '_') st->print("_1");
65 else if (c == '/') st->print("_");
66 else if (c == ';') st->print("_2");
67 else if (c == '[') st->print("_3");
68 else st->print("_%.5x", c);
69 }
70 }
71 }
72
73
74 static void mangle_name_on(outputStream* st, symbolOop name) {
75 mangle_name_on(st, name, 0, name->utf8_length());
76 }
77
78
79 char* NativeLookup::pure_jni_name(methodHandle method) {
80 stringStream st;
81 // Prefix
82 st.print("Java_");
83 // Klass name
84 mangle_name_on(&st, method->klass_name());
85 st.print("_");
86 // Method name
87 mangle_name_on(&st, method->name());
88 return st.as_string();
89 }
90
91
92 char* NativeLookup::long_jni_name(methodHandle method) {
93 // Signature ignore the wrapping parenteses and the trailing return type
94 stringStream st;
95 symbolOop signature = method->signature();
96 st.print("__");
97 // find ')'
98 int end;
99 for (end = 0; end < signature->utf8_length() && signature->byte_at(end) != ')'; end++);
100 // skip first '('
101 mangle_name_on(&st, signature, 1, end);
102 return st.as_string();
103 }
104
105 extern "C" {
106 void JNICALL JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls);
107 void JNICALL JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass unsafecls);
108 void JNICALL JVM_RegisterPerfMethods(JNIEnv *env, jclass perfclass);
109 }
110
111 static address lookup_special_native(char* jni_name) {
112 // NB: To ignore the jni prefix and jni postfix strstr is used matching.
113 if (!JDK_Version::is_gte_jdk14x_version()) {
114 // These functions only exist for compatibility with 1.3.1 and earlier
115 // Intercept ObjectOutputStream getPrimitiveFieldValues for faster serialization
116 if (strstr(jni_name, "Java_java_io_ObjectOutputStream_getPrimitiveFieldValues") != NULL) {
117 return CAST_FROM_FN_PTR(address, JVM_GetPrimitiveFieldValues);
118 }
119 // Intercept ObjectInputStream setPrimitiveFieldValues for faster serialization
120 if (strstr(jni_name, "Java_java_io_ObjectInputStream_setPrimitiveFieldValues") != NULL) {
121 return CAST_FROM_FN_PTR(address, JVM_SetPrimitiveFieldValues);
122 }
123 }
124 if (strstr(jni_name, "Java_sun_misc_Unsafe_registerNatives") != NULL) {
125 return CAST_FROM_FN_PTR(address, JVM_RegisterUnsafeMethods);
126 }
127 if (strstr(jni_name, "Java_sun_dyn_MethodHandleNatives_registerNatives") != NULL) {
128 return CAST_FROM_FN_PTR(address, JVM_RegisterMethodHandleMethods);
129 }
130 if (strstr(jni_name, "Java_sun_misc_Perf_registerNatives") != NULL) {
131 return CAST_FROM_FN_PTR(address, JVM_RegisterPerfMethods);
132 }
133
134 return NULL;
135 }
136
137 address NativeLookup::lookup_style(methodHandle method, char* pure_name, const char* long_name, int args_size, bool os_style, bool& in_base_library, TRAPS) {
138 address entry;
139 // Compute complete JNI name for style
140 stringStream st;
141 if (os_style) os::print_jni_name_prefix_on(&st, args_size);
142 st.print_raw(pure_name);
143 st.print_raw(long_name);
144 if (os_style) os::print_jni_name_suffix_on(&st, args_size);
145 char* jni_name = st.as_string();
146
147 // If the loader is null we have a system class, so we attempt a lookup in
148 // the native Java library. This takes care of any bootstrapping problems.
149 // Note: It is critical for bootstrapping that Java_java_lang_ClassLoader_00024NativeLibrary_find
150 // gets found the first time around - otherwise an infinite loop can occure. This is
151 // another VM/library dependency
152 Handle loader(THREAD,
153 instanceKlass::cast(method->method_holder())->class_loader());
154 if (loader.is_null()) {
155 entry = lookup_special_native(jni_name);
156 if (entry == NULL) {
157 entry = (address) hpi::dll_lookup(os::native_java_library(), jni_name);
158 }
159 if (entry != NULL) {
160 in_base_library = true;
161 return entry;
162 }
163 }
164
165 // Otherwise call static method findNative in ClassLoader
166 KlassHandle klass (THREAD, SystemDictionary::ClassLoader_klass());
167 Handle name_arg = java_lang_String::create_from_str(jni_name, CHECK_NULL);
168
169 JavaValue result(T_LONG);
170 JavaCalls::call_static(&result,
171 klass,
172 vmSymbolHandles::findNative_name(),
173 vmSymbolHandles::classloader_string_long_signature(),
174 // Arguments
175 loader,
176 name_arg,
177 CHECK_NULL);
178 entry = (address) (intptr_t) result.get_jlong();
179
180 if (entry == NULL) {
181 // findNative didn't find it, if there are any agent libraries look in them
182 AgentLibrary* agent;
183 for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
184 entry = (address) hpi::dll_lookup(agent->os_lib(), jni_name);
185 if (entry != NULL) {
186 return entry;
187 }
188 }
189 }
190
191 return entry;
192 }
193
194
195 // Check all the formats of native implementation name to see if there is one
196 // for the specified method.
197 address NativeLookup::lookup_entry(methodHandle method, bool& in_base_library, TRAPS) {
198 address entry = NULL;
199 in_base_library = false;
200 // Compute pure name
201 char* pure_name = pure_jni_name(method);
202
203 // Compute argument size
204 int args_size = 1 // JNIEnv
205 + (method->is_static() ? 1 : 0) // class for static methods
206 + method->size_of_parameters(); // actual parameters
207
208
209 // 1) Try JNI short style
210 entry = lookup_style(method, pure_name, "", args_size, true, in_base_library, CHECK_NULL);
211 if (entry != NULL) return entry;
212
213 // Compute long name
214 char* long_name = long_jni_name(method);
215
216 // 2) Try JNI long style
217 entry = lookup_style(method, pure_name, long_name, args_size, true, in_base_library, CHECK_NULL);
218 if (entry != NULL) return entry;
219
220 // 3) Try JNI short style without os prefix/suffix
221 entry = lookup_style(method, pure_name, "", args_size, false, in_base_library, CHECK_NULL);
222 if (entry != NULL) return entry;
223
224 // 4) Try JNI long style without os prefix/suffix
225 entry = lookup_style(method, pure_name, long_name, args_size, false, in_base_library, CHECK_NULL);
226
227 return entry; // NULL indicates not found
228 }
229
230 // Check if there are any JVM TI prefixes which have been applied to the native method name.
231 // If any are found, remove them before attemping the look up of the
232 // native implementation again.
233 // See SetNativeMethodPrefix in the JVM TI Spec for more details.
234 address NativeLookup::lookup_entry_prefixed(methodHandle method, bool& in_base_library, TRAPS) {
235 ResourceMark rm(THREAD);
236
237 int prefix_count;
238 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
239 char* in_name = method->name()->as_C_string();
240 char* wrapper_name = in_name;
241 // last applied prefix will be first -- go backwards
242 for (int i = prefix_count-1; i >= 0; i--) {
243 char* prefix = prefixes[i];
244 size_t prefix_len = strlen(prefix);
245 if (strncmp(prefix, wrapper_name, prefix_len) == 0) {
246 // has this prefix remove it
247 wrapper_name += prefix_len;
248 }
249 }
250 if (wrapper_name != in_name) {
251 // we have a name for a wrapping method
252 int wrapper_name_len = (int)strlen(wrapper_name);
253 symbolHandle wrapper_symbol(THREAD, SymbolTable::probe(wrapper_name, wrapper_name_len));
254 if (!wrapper_symbol.is_null()) {
255 KlassHandle kh(method->method_holder());
256 methodOop wrapper_method = Klass::cast(kh())->lookup_method(wrapper_symbol(),
257 method->signature());
258 if (wrapper_method != NULL && !wrapper_method->is_native()) {
259 // we found a wrapper method, use its native entry
260 method->set_is_prefixed_native();
261 return lookup_entry(wrapper_method, in_base_library, THREAD);
262 }
263 }
264 }
265 return NULL;
266 }
267
268 address NativeLookup::lookup_base(methodHandle method, bool& in_base_library, TRAPS) {
269 address entry = NULL;
270 ResourceMark rm(THREAD);
271
272 entry = lookup_entry(method, in_base_library, THREAD);
273 if (entry != NULL) return entry;
274
275 // standard native method resolution has failed. Check if there are any
276 // JVM TI prefixes which have been applied to the native method name.
277 entry = lookup_entry_prefixed(method, in_base_library, THREAD);
278 if (entry != NULL) return entry;
279
280 // Native function not found, throw UnsatisfiedLinkError
281 THROW_MSG_0(vmSymbols::java_lang_UnsatisfiedLinkError(),
282 method->name_and_sig_as_C_string());
283 }
284
285
286 address NativeLookup::lookup(methodHandle method, bool& in_base_library, TRAPS) {
287 if (!method->has_native_function()) {
288 address entry = lookup_base(method, in_base_library, CHECK_NULL);
289 method->set_native_function(entry,
290 methodOopDesc::native_bind_event_is_interesting);
291 // -verbose:jni printing
292 if (PrintJNIResolving) {
293 ResourceMark rm(THREAD);
294 tty->print_cr("[Dynamic-linking native method %s.%s ... JNI]",
295 Klass::cast(method->method_holder())->external_name(),
296 method->name()->as_C_string());
297 }
298 }
299 return method->native_function();
300 }
301
302 address NativeLookup::base_library_lookup(const char* class_name, const char* method_name, const char* signature) {
303 EXCEPTION_MARK;
304 bool in_base_library = true; // SharedRuntime inits some math methods.
305 symbolHandle c_name = oopFactory::new_symbol_handle(class_name, CATCH);
306 symbolHandle m_name = oopFactory::new_symbol_handle(method_name, CATCH);
307 symbolHandle s_name = oopFactory::new_symbol_handle(signature, CATCH);
308
309 // Find the class
310 klassOop k = SystemDictionary::resolve_or_fail(c_name, true, CATCH);
311 instanceKlassHandle klass (THREAD, k);
312
313 // Find method and invoke standard lookup
314 methodHandle method (THREAD,
315 klass->uncached_lookup_method(m_name(), s_name()));
316 address result = lookup(method, in_base_library, CATCH);
317 assert(in_base_library, "must be in basic library");
318 guarantee(result != NULL, "must be non NULL");
319 return result;
320 }