Mon, 15 Oct 2018 14:58:52 +0100
Merge
1 /*
2 * Copyright (c) 1997, 2017, 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 */
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/method.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 #include "utilities/macros.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 #ifdef TARGET_OS_FAMILY_aix
54 # include "os_aix.inline.hpp"
55 #endif
56 #ifdef TARGET_OS_FAMILY_bsd
57 # include "os_bsd.inline.hpp"
58 #endif
61 static void mangle_name_on(outputStream* st, Symbol* name, int begin, int end) {
62 char* bytes = (char*)name->bytes() + begin;
63 char* end_bytes = (char*)name->bytes() + end;
64 while (bytes < end_bytes) {
65 jchar c;
66 bytes = UTF8::next(bytes, &c);
67 if (c <= 0x7f && isalnum(c)) {
68 st->put((char) c);
69 } else {
70 if (c == '_') st->print("_1");
71 else if (c == '/') st->print("_");
72 else if (c == ';') st->print("_2");
73 else if (c == '[') st->print("_3");
74 else st->print("_%.5x", c);
75 }
76 }
77 }
80 static void mangle_name_on(outputStream* st, Symbol* name) {
81 mangle_name_on(st, name, 0, name->utf8_length());
82 }
85 char* NativeLookup::pure_jni_name(methodHandle method) {
86 stringStream st;
87 // Prefix
88 st.print("Java_");
89 // Klass name
90 mangle_name_on(&st, method->klass_name());
91 st.print("_");
92 // Method name
93 mangle_name_on(&st, method->name());
94 return st.as_string();
95 }
98 char* NativeLookup::critical_jni_name(methodHandle method) {
99 stringStream st;
100 // Prefix
101 st.print("JavaCritical_");
102 // Klass name
103 mangle_name_on(&st, method->klass_name());
104 st.print("_");
105 // Method name
106 mangle_name_on(&st, method->name());
107 return st.as_string();
108 }
111 char* NativeLookup::long_jni_name(methodHandle method) {
112 // Signature ignore the wrapping parenteses and the trailing return type
113 stringStream st;
114 Symbol* signature = method->signature();
115 st.print("__");
116 // find ')'
117 int end;
118 for (end = 0; end < signature->utf8_length() && signature->byte_at(end) != ')'; end++);
119 // skip first '('
120 mangle_name_on(&st, signature, 1, end);
121 return st.as_string();
122 }
124 extern "C" {
125 void JNICALL JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls);
126 void JNICALL JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass unsafecls);
127 void JNICALL JVM_RegisterPerfMethods(JNIEnv *env, jclass perfclass);
128 void JNICALL JVM_RegisterWhiteBoxMethods(JNIEnv *env, jclass wbclass);
129 }
131 #define CC (char*) /* cast a literal from (const char*) */
132 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
134 static JNINativeMethod lookup_special_native_methods[] = {
135 { CC"Java_sun_misc_Unsafe_registerNatives", NULL, FN_PTR(JVM_RegisterUnsafeMethods) },
136 { CC"Java_java_lang_invoke_MethodHandleNatives_registerNatives", NULL, FN_PTR(JVM_RegisterMethodHandleMethods) },
137 { CC"Java_sun_misc_Perf_registerNatives", NULL, FN_PTR(JVM_RegisterPerfMethods) },
138 { CC"Java_sun_hotspot_WhiteBox_registerNatives", NULL, FN_PTR(JVM_RegisterWhiteBoxMethods) },
139 };
141 static address lookup_special_native(char* jni_name) {
142 int count = sizeof(lookup_special_native_methods) / sizeof(JNINativeMethod);
143 for (int i = 0; i < count; i++) {
144 // NB: To ignore the jni prefix and jni postfix strstr is used matching.
145 if (strstr(jni_name, lookup_special_native_methods[i].name) != NULL) {
146 return CAST_FROM_FN_PTR(address, lookup_special_native_methods[i].fnPtr);
147 }
148 }
149 return NULL;
150 }
152 address NativeLookup::lookup_style(methodHandle method, char* pure_name, const char* long_name, int args_size, bool os_style, bool& in_base_library, TRAPS) {
153 address entry;
154 // Compute complete JNI name for style
155 stringStream st;
156 if (os_style) os::print_jni_name_prefix_on(&st, args_size);
157 st.print_raw(pure_name);
158 st.print_raw(long_name);
159 if (os_style) os::print_jni_name_suffix_on(&st, args_size);
160 char* jni_name = st.as_string();
162 // If the loader is null we have a system class, so we attempt a lookup in
163 // the native Java library. This takes care of any bootstrapping problems.
164 // Note: It is critical for bootstrapping that Java_java_lang_ClassLoader_00024NativeLibrary_find
165 // gets found the first time around - otherwise an infinite loop can occure. This is
166 // another VM/library dependency
167 Handle loader(THREAD, method->method_holder()->class_loader());
168 if (loader.is_null()) {
169 entry = lookup_special_native(jni_name);
170 if (entry == NULL) {
171 entry = (address) os::dll_lookup(os::native_java_library(), jni_name);
172 }
173 if (entry != NULL) {
174 in_base_library = true;
175 return entry;
176 }
177 }
179 // Otherwise call static method findNative in ClassLoader
180 KlassHandle klass (THREAD, SystemDictionary::ClassLoader_klass());
181 Handle name_arg = java_lang_String::create_from_str(jni_name, CHECK_NULL);
183 JavaValue result(T_LONG);
184 JavaCalls::call_static(&result,
185 klass,
186 vmSymbols::findNative_name(),
187 vmSymbols::classloader_string_long_signature(),
188 // Arguments
189 loader,
190 name_arg,
191 CHECK_NULL);
192 entry = (address) (intptr_t) result.get_jlong();
194 if (entry == NULL) {
195 // findNative didn't find it, if there are any agent libraries look in them
196 AgentLibrary* agent;
197 for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
198 entry = (address) os::dll_lookup(agent->os_lib(), jni_name);
199 if (entry != NULL) {
200 return entry;
201 }
202 }
203 }
205 return entry;
206 }
209 address NativeLookup::lookup_critical_style(methodHandle method, char* pure_name, const char* long_name, int args_size, bool os_style) {
210 if (!method->has_native_function()) {
211 return NULL;
212 }
214 address current_entry = method->native_function();
216 char dll_name[JVM_MAXPATHLEN];
217 int offset;
218 if (os::dll_address_to_library_name(current_entry, dll_name, sizeof(dll_name), &offset)) {
219 char ebuf[32];
220 void* dll = os::dll_load(dll_name, ebuf, sizeof(ebuf));
221 if (dll != NULL) {
222 // Compute complete JNI name for style
223 stringStream st;
224 if (os_style) os::print_jni_name_prefix_on(&st, args_size);
225 st.print_raw(pure_name);
226 st.print_raw(long_name);
227 if (os_style) os::print_jni_name_suffix_on(&st, args_size);
228 char* jni_name = st.as_string();
229 return (address)os::dll_lookup(dll, jni_name);
230 }
231 }
233 return NULL;
234 }
237 // Check all the formats of native implementation name to see if there is one
238 // for the specified method.
239 address NativeLookup::lookup_entry(methodHandle method, bool& in_base_library, TRAPS) {
240 address entry = NULL;
241 in_base_library = false;
242 // Compute pure name
243 char* pure_name = pure_jni_name(method);
245 // Compute argument size
246 int args_size = 1 // JNIEnv
247 + (method->is_static() ? 1 : 0) // class for static methods
248 + method->size_of_parameters(); // actual parameters
251 // 1) Try JNI short style
252 entry = lookup_style(method, pure_name, "", args_size, true, in_base_library, CHECK_NULL);
253 if (entry != NULL) return entry;
255 // Compute long name
256 char* long_name = long_jni_name(method);
258 // 2) Try JNI long style
259 entry = lookup_style(method, pure_name, long_name, args_size, true, in_base_library, CHECK_NULL);
260 if (entry != NULL) return entry;
262 // 3) Try JNI short style without os prefix/suffix
263 entry = lookup_style(method, pure_name, "", args_size, false, in_base_library, CHECK_NULL);
264 if (entry != NULL) return entry;
266 // 4) Try JNI long style without os prefix/suffix
267 entry = lookup_style(method, pure_name, long_name, args_size, false, in_base_library, CHECK_NULL);
269 return entry; // NULL indicates not found
270 }
272 // Check all the formats of native implementation name to see if there is one
273 // for the specified method.
274 address NativeLookup::lookup_critical_entry(methodHandle method) {
275 if (!CriticalJNINatives) return NULL;
277 if (method->is_synchronized() ||
278 !method->is_static()) {
279 // Only static non-synchronized methods are allowed
280 return NULL;
281 }
283 ResourceMark rm;
284 address entry = NULL;
286 Symbol* signature = method->signature();
287 for (int end = 0; end < signature->utf8_length(); end++) {
288 if (signature->byte_at(end) == 'L') {
289 // Don't allow object types
290 return NULL;
291 }
292 }
294 // Compute critical name
295 char* critical_name = critical_jni_name(method);
297 // Compute argument size
298 int args_size = 1 // JNIEnv
299 + (method->is_static() ? 1 : 0) // class for static methods
300 + method->size_of_parameters(); // actual parameters
303 // 1) Try JNI short style
304 entry = lookup_critical_style(method, critical_name, "", args_size, true);
305 if (entry != NULL) return entry;
307 // Compute long name
308 char* long_name = long_jni_name(method);
310 // 2) Try JNI long style
311 entry = lookup_critical_style(method, critical_name, long_name, args_size, true);
312 if (entry != NULL) return entry;
314 // 3) Try JNI short style without os prefix/suffix
315 entry = lookup_critical_style(method, critical_name, "", args_size, false);
316 if (entry != NULL) return entry;
318 // 4) Try JNI long style without os prefix/suffix
319 entry = lookup_critical_style(method, critical_name, long_name, args_size, false);
321 return entry; // NULL indicates not found
322 }
324 // Check if there are any JVM TI prefixes which have been applied to the native method name.
325 // If any are found, remove them before attemping the look up of the
326 // native implementation again.
327 // See SetNativeMethodPrefix in the JVM TI Spec for more details.
328 address NativeLookup::lookup_entry_prefixed(methodHandle method, bool& in_base_library, TRAPS) {
329 #if INCLUDE_JVMTI
330 ResourceMark rm(THREAD);
332 int prefix_count;
333 char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
334 char* in_name = method->name()->as_C_string();
335 char* wrapper_name = in_name;
336 // last applied prefix will be first -- go backwards
337 for (int i = prefix_count-1; i >= 0; i--) {
338 char* prefix = prefixes[i];
339 size_t prefix_len = strlen(prefix);
340 if (strncmp(prefix, wrapper_name, prefix_len) == 0) {
341 // has this prefix remove it
342 wrapper_name += prefix_len;
343 }
344 }
345 if (wrapper_name != in_name) {
346 // we have a name for a wrapping method
347 int wrapper_name_len = (int)strlen(wrapper_name);
348 TempNewSymbol wrapper_symbol = SymbolTable::probe(wrapper_name, wrapper_name_len);
349 if (wrapper_symbol != NULL) {
350 KlassHandle kh(method->method_holder());
351 Method* wrapper_method = kh()->lookup_method(wrapper_symbol,
352 method->signature());
353 if (wrapper_method != NULL && !wrapper_method->is_native()) {
354 // we found a wrapper method, use its native entry
355 method->set_is_prefixed_native();
356 return lookup_entry(wrapper_method, in_base_library, THREAD);
357 }
358 }
359 }
360 #endif // INCLUDE_JVMTI
361 return NULL;
362 }
364 address NativeLookup::lookup_base(methodHandle method, bool& in_base_library, TRAPS) {
365 address entry = NULL;
366 ResourceMark rm(THREAD);
368 entry = lookup_entry(method, in_base_library, THREAD);
369 if (entry != NULL) return entry;
371 // standard native method resolution has failed. Check if there are any
372 // JVM TI prefixes which have been applied to the native method name.
373 entry = lookup_entry_prefixed(method, in_base_library, THREAD);
374 if (entry != NULL) return entry;
376 // Native function not found, throw UnsatisfiedLinkError
377 THROW_MSG_0(vmSymbols::java_lang_UnsatisfiedLinkError(),
378 method->name_and_sig_as_C_string());
379 }
382 address NativeLookup::lookup(methodHandle method, bool& in_base_library, TRAPS) {
383 if (!method->has_native_function()) {
384 address entry = lookup_base(method, in_base_library, CHECK_NULL);
385 method->set_native_function(entry,
386 Method::native_bind_event_is_interesting);
387 // -verbose:jni printing
388 if (PrintJNIResolving) {
389 ResourceMark rm(THREAD);
390 tty->print_cr("[Dynamic-linking native method %s.%s ... JNI]",
391 method->method_holder()->external_name(),
392 method->name()->as_C_string());
393 }
394 }
395 return method->native_function();
396 }
398 address NativeLookup::base_library_lookup(const char* class_name, const char* method_name, const char* signature) {
399 EXCEPTION_MARK;
400 bool in_base_library = true; // SharedRuntime inits some math methods.
401 TempNewSymbol c_name = SymbolTable::new_symbol(class_name, CATCH);
402 TempNewSymbol m_name = SymbolTable::new_symbol(method_name, CATCH);
403 TempNewSymbol s_name = SymbolTable::new_symbol(signature, CATCH);
405 // Find the class
406 Klass* k = SystemDictionary::resolve_or_fail(c_name, true, CATCH);
407 instanceKlassHandle klass (THREAD, k);
409 // Find method and invoke standard lookup
410 methodHandle method (THREAD,
411 klass->uncached_lookup_method(m_name, s_name, Klass::find_overpass));
412 address result = lookup(method, in_base_library, CATCH);
413 assert(in_base_library, "must be in basic library");
414 guarantee(result != NULL, "must be non NULL");
415 return result;
416 }