--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/prims/nativeLookup.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,413 @@
+/*
+ * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code 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 General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "classfile/javaClasses.hpp"
+#include "classfile/systemDictionary.hpp"
+#include "classfile/vmSymbols.hpp"
+#include "memory/oopFactory.hpp"
+#include "memory/resourceArea.hpp"
+#include "memory/universe.inline.hpp"
+#include "oops/instanceKlass.hpp"
+#include "oops/method.hpp"
+#include "oops/oop.inline.hpp"
+#include "oops/symbol.hpp"
+#include "prims/jvm_misc.hpp"
+#include "prims/nativeLookup.hpp"
+#include "prims/unsafe.hpp"
+#include "runtime/arguments.hpp"
+#include "runtime/handles.inline.hpp"
+#include "runtime/javaCalls.hpp"
+#include "runtime/sharedRuntime.hpp"
+#include "runtime/signature.hpp"
+#include "utilities/macros.hpp"
+#if INCLUDE_TRACE
+#include "trace/traceMacros.hpp"
+#endif
+
+static void mangle_name_on(outputStream* st, Symbol* name, int begin, int end) {
+ char* bytes = (char*)name->bytes() + begin;
+ char* end_bytes = (char*)name->bytes() + end;
+ while (bytes < end_bytes) {
+ jchar c;
+ bytes = UTF8::next(bytes, &c);
+ if (c <= 0x7f && isalnum(c)) {
+ st->put((char) c);
+ } else {
+ if (c == '_') st->print("_1");
+ else if (c == '/') st->print("_");
+ else if (c == ';') st->print("_2");
+ else if (c == '[') st->print("_3");
+ else st->print("_%.5x", c);
+ }
+ }
+}
+
+
+static void mangle_name_on(outputStream* st, Symbol* name) {
+ mangle_name_on(st, name, 0, name->utf8_length());
+}
+
+
+char* NativeLookup::pure_jni_name(const methodHandle& method) {
+ stringStream st;
+ // Prefix
+ st.print("Java_");
+ // Klass name
+ mangle_name_on(&st, method->klass_name());
+ st.print("_");
+ // Method name
+ mangle_name_on(&st, method->name());
+ return st.as_string();
+}
+
+
+char* NativeLookup::critical_jni_name(const methodHandle& method) {
+ stringStream st;
+ // Prefix
+ st.print("JavaCritical_");
+ // Klass name
+ mangle_name_on(&st, method->klass_name());
+ st.print("_");
+ // Method name
+ mangle_name_on(&st, method->name());
+ return st.as_string();
+}
+
+
+char* NativeLookup::long_jni_name(const methodHandle& method) {
+ // Signature ignore the wrapping parenteses and the trailing return type
+ stringStream st;
+ Symbol* signature = method->signature();
+ st.print("__");
+ // find ')'
+ int end;
+ for (end = 0; end < signature->utf8_length() && signature->byte_at(end) != ')'; end++);
+ // skip first '('
+ mangle_name_on(&st, signature, 1, end);
+ return st.as_string();
+}
+
+extern "C" {
+ void JNICALL JVM_RegisterMethodHandleMethods(JNIEnv *env, jclass unsafecls);
+ void JNICALL JVM_RegisterPerfMethods(JNIEnv *env, jclass perfclass);
+ void JNICALL JVM_RegisterWhiteBoxMethods(JNIEnv *env, jclass wbclass);
+#if INCLUDE_JVMCI
+ jobject JNICALL JVM_GetJVMCIRuntime(JNIEnv *env, jclass c);
+ void JNICALL JVM_RegisterJVMCINatives(JNIEnv *env, jclass compilerToVMClass);
+#endif
+}
+
+#define CC (char*) /* cast a literal from (const char*) */
+#define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
+
+static JNINativeMethod lookup_special_native_methods[] = {
+ { CC"Java_jdk_internal_misc_Unsafe_registerNatives", NULL, FN_PTR(JVM_RegisterJDKInternalMiscUnsafeMethods) },
+ { CC"Java_java_lang_invoke_MethodHandleNatives_registerNatives", NULL, FN_PTR(JVM_RegisterMethodHandleMethods) },
+ { CC"Java_jdk_internal_perf_Perf_registerNatives", NULL, FN_PTR(JVM_RegisterPerfMethods) },
+ { CC"Java_sun_hotspot_WhiteBox_registerNatives", NULL, FN_PTR(JVM_RegisterWhiteBoxMethods) },
+#if INCLUDE_JVMCI
+ { CC"Java_jdk_vm_ci_runtime_JVMCI_initializeRuntime", NULL, FN_PTR(JVM_GetJVMCIRuntime) },
+ { CC"Java_jdk_vm_ci_hotspot_CompilerToVM_registerNatives", NULL, FN_PTR(JVM_RegisterJVMCINatives) },
+#endif
+#if INCLUDE_TRACE
+ { CC"Java_jdk_jfr_internal_JVM_registerNatives", NULL, TRACE_REGISTER_NATIVES },
+#endif
+};
+
+static address lookup_special_native(char* jni_name) {
+ int count = sizeof(lookup_special_native_methods) / sizeof(JNINativeMethod);
+ for (int i = 0; i < count; i++) {
+ // NB: To ignore the jni prefix and jni postfix strstr is used matching.
+ if (strstr(jni_name, lookup_special_native_methods[i].name) != NULL) {
+ return CAST_FROM_FN_PTR(address, lookup_special_native_methods[i].fnPtr);
+ }
+ }
+ return NULL;
+}
+
+address NativeLookup::lookup_style(const methodHandle& method, char* pure_name, const char* long_name, int args_size, bool os_style, bool& in_base_library, TRAPS) {
+ address entry;
+ // Compute complete JNI name for style
+ stringStream st;
+ if (os_style) os::print_jni_name_prefix_on(&st, args_size);
+ st.print_raw(pure_name);
+ st.print_raw(long_name);
+ if (os_style) os::print_jni_name_suffix_on(&st, args_size);
+ char* jni_name = st.as_string();
+
+ // If the loader is null we have a system class, so we attempt a lookup in
+ // the native Java library. This takes care of any bootstrapping problems.
+ // Note: It is critical for bootstrapping that Java_java_lang_ClassLoader_00024NativeLibrary_find
+ // gets found the first time around - otherwise an infinite loop can occure. This is
+ // another VM/library dependency
+ Handle loader(THREAD, method->method_holder()->class_loader());
+ if (loader.is_null()) {
+ entry = lookup_special_native(jni_name);
+ if (entry == NULL) {
+ entry = (address) os::dll_lookup(os::native_java_library(), jni_name);
+ }
+ if (entry != NULL) {
+ in_base_library = true;
+ return entry;
+ }
+ }
+
+ // Otherwise call static method findNative in ClassLoader
+ Klass* klass = SystemDictionary::ClassLoader_klass();
+ Handle name_arg = java_lang_String::create_from_str(jni_name, CHECK_NULL);
+
+ JavaValue result(T_LONG);
+ JavaCalls::call_static(&result,
+ klass,
+ vmSymbols::findNative_name(),
+ vmSymbols::classloader_string_long_signature(),
+ // Arguments
+ loader,
+ name_arg,
+ CHECK_NULL);
+ entry = (address) (intptr_t) result.get_jlong();
+
+ if (entry == NULL) {
+ // findNative didn't find it, if there are any agent libraries look in them
+ AgentLibrary* agent;
+ for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
+ entry = (address) os::dll_lookup(agent->os_lib(), jni_name);
+ if (entry != NULL) {
+ return entry;
+ }
+ }
+ }
+
+ return entry;
+}
+
+
+address NativeLookup::lookup_critical_style(const methodHandle& method, char* pure_name, const char* long_name, int args_size, bool os_style) {
+ if (!method->has_native_function()) {
+ return NULL;
+ }
+
+ address current_entry = method->native_function();
+
+ char dll_name[JVM_MAXPATHLEN];
+ int offset;
+ if (os::dll_address_to_library_name(current_entry, dll_name, sizeof(dll_name), &offset)) {
+ char ebuf[32];
+ void* dll = os::dll_load(dll_name, ebuf, sizeof(ebuf));
+ if (dll != NULL) {
+ // Compute complete JNI name for style
+ stringStream st;
+ if (os_style) os::print_jni_name_prefix_on(&st, args_size);
+ st.print_raw(pure_name);
+ st.print_raw(long_name);
+ if (os_style) os::print_jni_name_suffix_on(&st, args_size);
+ char* jni_name = st.as_string();
+ return (address)os::dll_lookup(dll, jni_name);
+ }
+ }
+
+ return NULL;
+}
+
+
+// Check all the formats of native implementation name to see if there is one
+// for the specified method.
+address NativeLookup::lookup_entry(const methodHandle& method, bool& in_base_library, TRAPS) {
+ address entry = NULL;
+ in_base_library = false;
+ // Compute pure name
+ char* pure_name = pure_jni_name(method);
+
+ // Compute argument size
+ int args_size = 1 // JNIEnv
+ + (method->is_static() ? 1 : 0) // class for static methods
+ + method->size_of_parameters(); // actual parameters
+
+
+ // 1) Try JNI short style
+ entry = lookup_style(method, pure_name, "", args_size, true, in_base_library, CHECK_NULL);
+ if (entry != NULL) return entry;
+
+ // Compute long name
+ char* long_name = long_jni_name(method);
+
+ // 2) Try JNI long style
+ entry = lookup_style(method, pure_name, long_name, args_size, true, in_base_library, CHECK_NULL);
+ if (entry != NULL) return entry;
+
+ // 3) Try JNI short style without os prefix/suffix
+ entry = lookup_style(method, pure_name, "", args_size, false, in_base_library, CHECK_NULL);
+ if (entry != NULL) return entry;
+
+ // 4) Try JNI long style without os prefix/suffix
+ entry = lookup_style(method, pure_name, long_name, args_size, false, in_base_library, CHECK_NULL);
+
+ return entry; // NULL indicates not found
+}
+
+// Check all the formats of native implementation name to see if there is one
+// for the specified method.
+address NativeLookup::lookup_critical_entry(const methodHandle& method) {
+ if (!CriticalJNINatives) return NULL;
+
+ if (method->is_synchronized() ||
+ !method->is_static()) {
+ // Only static non-synchronized methods are allowed
+ return NULL;
+ }
+
+ ResourceMark rm;
+ address entry = NULL;
+
+ Symbol* signature = method->signature();
+ for (int end = 0; end < signature->utf8_length(); end++) {
+ if (signature->byte_at(end) == 'L') {
+ // Don't allow object types
+ return NULL;
+ }
+ }
+
+ // Compute critical name
+ char* critical_name = critical_jni_name(method);
+
+ // Compute argument size
+ int args_size = 1 // JNIEnv
+ + (method->is_static() ? 1 : 0) // class for static methods
+ + method->size_of_parameters(); // actual parameters
+
+
+ // 1) Try JNI short style
+ entry = lookup_critical_style(method, critical_name, "", args_size, true);
+ if (entry != NULL) return entry;
+
+ // Compute long name
+ char* long_name = long_jni_name(method);
+
+ // 2) Try JNI long style
+ entry = lookup_critical_style(method, critical_name, long_name, args_size, true);
+ if (entry != NULL) return entry;
+
+ // 3) Try JNI short style without os prefix/suffix
+ entry = lookup_critical_style(method, critical_name, "", args_size, false);
+ if (entry != NULL) return entry;
+
+ // 4) Try JNI long style without os prefix/suffix
+ entry = lookup_critical_style(method, critical_name, long_name, args_size, false);
+
+ return entry; // NULL indicates not found
+}
+
+// Check if there are any JVM TI prefixes which have been applied to the native method name.
+// If any are found, remove them before attemping the look up of the
+// native implementation again.
+// See SetNativeMethodPrefix in the JVM TI Spec for more details.
+address NativeLookup::lookup_entry_prefixed(const methodHandle& method, bool& in_base_library, TRAPS) {
+#if INCLUDE_JVMTI
+ ResourceMark rm(THREAD);
+
+ int prefix_count;
+ char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
+ char* in_name = method->name()->as_C_string();
+ char* wrapper_name = in_name;
+ // last applied prefix will be first -- go backwards
+ for (int i = prefix_count-1; i >= 0; i--) {
+ char* prefix = prefixes[i];
+ size_t prefix_len = strlen(prefix);
+ if (strncmp(prefix, wrapper_name, prefix_len) == 0) {
+ // has this prefix remove it
+ wrapper_name += prefix_len;
+ }
+ }
+ if (wrapper_name != in_name) {
+ // we have a name for a wrapping method
+ int wrapper_name_len = (int)strlen(wrapper_name);
+ TempNewSymbol wrapper_symbol = SymbolTable::probe(wrapper_name, wrapper_name_len);
+ if (wrapper_symbol != NULL) {
+ Klass* k = method->method_holder();
+ Method* wrapper_method = k->lookup_method(wrapper_symbol, method->signature());
+ if (wrapper_method != NULL && !wrapper_method->is_native()) {
+ // we found a wrapper method, use its native entry
+ method->set_is_prefixed_native();
+ return lookup_entry(wrapper_method, in_base_library, THREAD);
+ }
+ }
+ }
+#endif // INCLUDE_JVMTI
+ return NULL;
+}
+
+address NativeLookup::lookup_base(const methodHandle& method, bool& in_base_library, TRAPS) {
+ address entry = NULL;
+ ResourceMark rm(THREAD);
+
+ entry = lookup_entry(method, in_base_library, THREAD);
+ if (entry != NULL) return entry;
+
+ // standard native method resolution has failed. Check if there are any
+ // JVM TI prefixes which have been applied to the native method name.
+ entry = lookup_entry_prefixed(method, in_base_library, THREAD);
+ if (entry != NULL) return entry;
+
+ // Native function not found, throw UnsatisfiedLinkError
+ THROW_MSG_0(vmSymbols::java_lang_UnsatisfiedLinkError(),
+ method->name_and_sig_as_C_string());
+}
+
+
+address NativeLookup::lookup(const methodHandle& method, bool& in_base_library, TRAPS) {
+ if (!method->has_native_function()) {
+ address entry = lookup_base(method, in_base_library, CHECK_NULL);
+ method->set_native_function(entry,
+ Method::native_bind_event_is_interesting);
+ // -verbose:jni printing
+ if (PrintJNIResolving) {
+ ResourceMark rm(THREAD);
+ tty->print_cr("[Dynamic-linking native method %s.%s ... JNI]",
+ method->method_holder()->external_name(),
+ method->name()->as_C_string());
+ }
+ }
+ return method->native_function();
+}
+
+address NativeLookup::base_library_lookup(const char* class_name, const char* method_name, const char* signature) {
+ EXCEPTION_MARK;
+ bool in_base_library = true; // SharedRuntime inits some math methods.
+ TempNewSymbol c_name = SymbolTable::new_symbol(class_name, CATCH);
+ TempNewSymbol m_name = SymbolTable::new_symbol(method_name, CATCH);
+ TempNewSymbol s_name = SymbolTable::new_symbol(signature, CATCH);
+
+ // Find the class
+ Klass* k = SystemDictionary::resolve_or_fail(c_name, true, CATCH);
+ InstanceKlass* klass = InstanceKlass::cast(k);
+
+ // Find method and invoke standard lookup
+ methodHandle method (THREAD,
+ klass->uncached_lookup_method(m_name, s_name, Klass::find_overpass));
+ address result = lookup(method, in_base_library, CATCH);
+ assert(in_base_library, "must be in basic library");
+ guarantee(result != NULL, "must be non NULL");
+ return result;
+}