1 /*
2 * Copyright (c) 1997, 2011, 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/symbol.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/javaCalls.hpp"
41 #include "runtime/sharedRuntime.hpp"
42 #include "runtime/signature.hpp"
43 #ifdef TARGET_OS_FAMILY_linux
44 # include "os_linux.inline.hpp"
45 #endif
46 #ifdef TARGET_OS_FAMILY_solaris
47 # include "os_solaris.inline.hpp"
48 #endif
49 #ifdef TARGET_OS_FAMILY_windows
50 # include "os_windows.inline.hpp"
51 #endif
52
53
54 static void mangle_name_on(outputStream* st, Symbol* name, int begin, int end) {
55 char* bytes = (char*)name->bytes() + begin;
56 char* end_bytes = (char*)name->bytes() + end;
57 while (bytes < end_bytes) {
58 jchar c;
59 bytes = UTF8::next(bytes, &c);
60 if (c <= 0x7f && isalnum(c)) {
61 st->put((char) c);
62 } else {
63 if (c == '_') st->print("_1");
64 else if (c == '/') st->print("_");
65 else if (c == ';') st->print("_2");
66 else if (c == '[') st->print("_3");
67 else st->print("_%.5x", c);
68 }
69 }
70 }
71
72
73 static void mangle_name_on(outputStream* st, Symbol* name) {
74 mangle_name_on(st, name, 0, name->utf8_length());
75 }
76
77
78 char* NativeLookup::pure_jni_name(methodHandle method) {
79 stringStream st;
80 // Prefix
81 st.print("Java_");
82 // Klass name
83 mangle_name_on(&st, method->klass_name());
84 st.print("_");
85 // Method name
86 mangle_name_on(&st, method->name());
87 return st.as_string();
88 }
89
90
91 char* NativeLookup::long_jni_name(methodHandle method) {
92 // Signature ignore the wrapping parenteses and the trailing return type
93 stringStream st;
94 Symbol* signature = method->signature();
95 st.print("__");
96 // find ')'
97 int end;
98 for (end = 0; end < signature->utf8_length() && signature->byte_at(end) != ')'; end++);
99 // skip first '('
100 mangle_name_on(&st, signature, 1, end);
101 return st.as_string();
102 }
103
104 extern "C" {
105 void JNICALL JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls);
106 void JNICALL JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass unsafecls);
107 void JNICALL JVM_RegisterPerfMethods(JNIEnv *env, jclass perfclass);
108 }
109
110 #define CC (char*) /* cast a literal from (const char*) */
111 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
112
113 static JNINativeMethod lookup_special_native_methods[] = {
114 // Next two functions only exist for compatibility with 1.3.1 and earlier.
115 { CC"Java_java_io_ObjectOutputStream_getPrimitiveFieldValues", NULL, FN_PTR(JVM_GetPrimitiveFieldValues) }, // intercept ObjectOutputStream getPrimitiveFieldValues for faster serialization
116 { CC"Java_java_io_ObjectInputStream_setPrimitiveFieldValues", NULL, FN_PTR(JVM_SetPrimitiveFieldValues) }, // intercept ObjectInputStream setPrimitiveFieldValues for faster serialization
117
118 { CC"Java_sun_misc_Unsafe_registerNatives", NULL, FN_PTR(JVM_RegisterUnsafeMethods) },
119 { CC"Java_sun_dyn_MethodHandleNatives_registerNatives", NULL, FN_PTR(JVM_RegisterMethodHandleMethods) }, // AllowTransitionalJSR292
120 { CC"Java_java_dyn_MethodHandleNatives_registerNatives", NULL, FN_PTR(JVM_RegisterMethodHandleMethods) }, // AllowTransitionalJSR292
121 { CC"Java_sun_misc_Perf_registerNatives", NULL, FN_PTR(JVM_RegisterPerfMethods) }
122 };
123
124 static address lookup_special_native(char* jni_name) {
125 int i = !JDK_Version::is_gte_jdk14x_version() ? 0 : 2; // see comment in lookup_special_native_methods
126 int count = sizeof(lookup_special_native_methods) / sizeof(JNINativeMethod);
127 for (; i < count; i++) {
128 // NB: To ignore the jni prefix and jni postfix strstr is used matching.
129 if (strstr(jni_name, lookup_special_native_methods[i].name) != NULL) {
130 return CAST_FROM_FN_PTR(address, lookup_special_native_methods[i].fnPtr);
131 }
132 }
133 return NULL;
134 }
135
136 address NativeLookup::lookup_style(methodHandle method, char* pure_name, const char* long_name, int args_size, bool os_style, bool& in_base_library, TRAPS) {
137 address entry;
138 // Compute complete JNI name for style
139 stringStream st;
140 if (os_style) os::print_jni_name_prefix_on(&st, args_size);
141 st.print_raw(pure_name);
142 st.print_raw(long_name);
143 if (os_style) os::print_jni_name_suffix_on(&st, args_size);
144 char* jni_name = st.as_string();
145
146 // If the loader is null we have a system class, so we attempt a lookup in
147 // the native Java library. This takes care of any bootstrapping problems.
148 // Note: It is critical for bootstrapping that Java_java_lang_ClassLoader_00024NativeLibrary_find
149 // gets found the first time around - otherwise an infinite loop can occure. This is
150 // another VM/library dependency
151 Handle loader(THREAD,
152 instanceKlass::cast(method->method_holder())->class_loader());
153 if (loader.is_null()) {
154 entry = lookup_special_native(jni_name);
155 if (entry == NULL) {
156 entry = (address) os::dll_lookup(os::native_java_library(), jni_name);
157 }
158 if (entry != NULL) {
159 in_base_library = true;
160 return entry;
161 }
162 }
163
164 // Otherwise call static method findNative in ClassLoader
165 KlassHandle klass (THREAD, SystemDictionary::ClassLoader_klass());
166 Handle name_arg = java_lang_String::create_from_str(jni_name, CHECK_NULL);
167
168 JavaValue result(T_LONG);
169 JavaCalls::call_static(&result,
170 klass,
171 vmSymbols::findNative_name(),
172 vmSymbols::classloader_string_long_signature(),
173 // Arguments
174 loader,
175 name_arg,
176 CHECK_NULL);
177 entry = (address) (intptr_t) result.get_jlong();
178
179 if (entry == NULL) {
180 // findNative didn't find it, if there are any agent libraries look in them
181 AgentLibrary* agent;
182 for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
183 entry = (address) os::dll_lookup(agent->os_lib(), jni_name);
184 if (entry != NULL) {
185 return entry;
186 }
187 }
188 }
189
190 return entry;
191 }
192
193
194 // Check all the formats of native implementation name to see if there is one
195 // for the specified method.
196 address NativeLookup::lookup_entry(methodHandle method, bool& in_base_library, TRAPS) {
197 address entry = NULL;
198 in_base_library = false;
199 // Compute pure name
200 char* pure_name = pure_jni_name(method);
201
202 // Compute argument size
203 int args_size = 1 // JNIEnv
204 + (method->is_static() ? 1 : 0) // class for static methods
205 + method->size_of_parameters(); // actual parameters
206
207
208 // 1) Try JNI short style
209 entry = lookup_style(method, pure_name, "", args_size, true, in_base_library, CHECK_NULL);
210 if (entry != NULL) return entry;
211
212 // Compute long name
213 char* long_name = long_jni_name(method);
214
215 // 2) Try JNI long style
216 entry = lookup_style(method, pure_name, long_name, args_size, true, in_base_library, CHECK_NULL);
217 if (entry != NULL) return entry;
218
219 // 3) Try JNI short style without os prefix/suffix
220 entry = lookup_style(method, pure_name, "", args_size, false, in_base_library, CHECK_NULL);
221 if (entry != NULL) return entry;
222
223 // 4) Try JNI long style without os prefix/suffix
224 entry = lookup_style(method, pure_name, long_name, args_size, false, in_base_library, CHECK_NULL);
225
226 return entry; // NULL indicates not found
227 }
228
229 // Check if there are any JVM TI prefixes which have been applied to the native method name.
230 // If any are found, remove them before attemping the look up of the
231 // native implementation again.
232 // See SetNativeMethodPrefix in the JVM TI Spec for more details.
233 address NativeLookup::lookup_entry_prefixed(methodHandle method, bool& in_base_library, TRAPS) {
234 ResourceMark rm(THREAD);
235
236 int prefix_count;
237 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
238 char* in_name = method->name()->as_C_string();
239 char* wrapper_name = in_name;
240 // last applied prefix will be first -- go backwards
241 for (int i = prefix_count-1; i >= 0; i--) {
242 char* prefix = prefixes[i];
243 size_t prefix_len = strlen(prefix);
244 if (strncmp(prefix, wrapper_name, prefix_len) == 0) {
245 // has this prefix remove it
246 wrapper_name += prefix_len;
247 }
248 }
249 if (wrapper_name != in_name) {
250 // we have a name for a wrapping method
251 int wrapper_name_len = (int)strlen(wrapper_name);
252 TempNewSymbol wrapper_symbol = SymbolTable::probe(wrapper_name, wrapper_name_len);
253 if (wrapper_symbol != NULL) {
254 KlassHandle kh(method->method_holder());
255 methodOop wrapper_method = Klass::cast(kh())->lookup_method(wrapper_symbol,
256 method->signature());
257 if (wrapper_method != NULL && !wrapper_method->is_native()) {
258 // we found a wrapper method, use its native entry
259 method->set_is_prefixed_native();
260 return lookup_entry(wrapper_method, in_base_library, THREAD);
261 }
262 }
263 }
264 return NULL;
265 }
266
267 address NativeLookup::lookup_base(methodHandle method, bool& in_base_library, TRAPS) {
268 address entry = NULL;
269 ResourceMark rm(THREAD);
270
271 entry = lookup_entry(method, in_base_library, THREAD);
272 if (entry != NULL) return entry;
273
274 // standard native method resolution has failed. Check if there are any
275 // JVM TI prefixes which have been applied to the native method name.
276 entry = lookup_entry_prefixed(method, in_base_library, THREAD);
277 if (entry != NULL) return entry;
278
279 // Native function not found, throw UnsatisfiedLinkError
280 THROW_MSG_0(vmSymbols::java_lang_UnsatisfiedLinkError(),
281 method->name_and_sig_as_C_string());
282 }
283
284
285 address NativeLookup::lookup(methodHandle method, bool& in_base_library, TRAPS) {
286 if (!method->has_native_function()) {
287 address entry = lookup_base(method, in_base_library, CHECK_NULL);
288 method->set_native_function(entry,
289 methodOopDesc::native_bind_event_is_interesting);
290 // -verbose:jni printing
291 if (PrintJNIResolving) {
292 ResourceMark rm(THREAD);
293 tty->print_cr("[Dynamic-linking native method %s.%s ... JNI]",
294 Klass::cast(method->method_holder())->external_name(),
295 method->name()->as_C_string());
296 }
297 }
298 return method->native_function();
299 }
300
301 address NativeLookup::base_library_lookup(const char* class_name, const char* method_name, const char* signature) {
302 EXCEPTION_MARK;
303 bool in_base_library = true; // SharedRuntime inits some math methods.
304 TempNewSymbol c_name = SymbolTable::new_symbol(class_name, CATCH);
305 TempNewSymbol m_name = SymbolTable::new_symbol(method_name, CATCH);
306 TempNewSymbol s_name = SymbolTable::new_symbol(signature, CATCH);
307
308 // Find the class
309 klassOop k = SystemDictionary::resolve_or_fail(c_name, true, CATCH);
310 instanceKlassHandle klass (THREAD, k);
311
312 // Find method and invoke standard lookup
313 methodHandle method (THREAD,
314 klass->uncached_lookup_method(m_name, s_name));
315 address result = lookup(method, in_base_library, CATCH);
316 assert(in_base_library, "must be in basic library");
317 guarantee(result != NULL, "must be non NULL");
318 return result;
319 }