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/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// A simple implementation of the native-bridge interface.
#include <dlfcn.h>
#include <setjmp.h>
#include <signal.h>
#include <sys/stat.h>
#include <unistd.h>
#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <vector>
#include <jni.h>
#include <nativebridge/native_bridge.h>
#include "base/macros.h"
struct NativeBridgeMethod {
const char* name;
const char* signature;
bool static_method;
void* fnPtr;
void* trampoline;
};
static NativeBridgeMethod* find_native_bridge_method(const char *name);
static const android::NativeBridgeRuntimeCallbacks* gNativeBridgeArtCallbacks;
static jint trampoline_JNI_OnLoad(JavaVM* vm, void* reserved) {
JNIEnv* env = nullptr;
using FnPtr_t = jint(*)(JavaVM*, void*);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>(find_native_bridge_method("JNI_OnLoad")->fnPtr);
vm->GetEnv(reinterpret_cast<void **>(&env), JNI_VERSION_1_6);
if (env == nullptr) {
return 0;
}
jclass klass = env->FindClass("Main");
if (klass != nullptr) {
int i, count1, count2;
count1 = gNativeBridgeArtCallbacks->getNativeMethodCount(env, klass);
std::unique_ptr<JNINativeMethod[]> methods(new JNINativeMethod[count1]);
if (methods == nullptr) {
return 0;
}
count2 = gNativeBridgeArtCallbacks->getNativeMethods(env, klass, methods.get(), count1);
if (count1 == count2) {
printf("Test ART callbacks: all JNI function number is %d.\n", count1);
}
for (i = 0; i < count1; i++) {
NativeBridgeMethod* nb_method = find_native_bridge_method(methods[i].name);
if (nb_method != nullptr) {
jmethodID mid = nullptr;
if (nb_method->static_method) {
mid = env->GetStaticMethodID(klass, methods[i].name, nb_method->signature);
} else {
mid = env->GetMethodID(klass, methods[i].name, nb_method->signature);
}
if (mid != nullptr) {
const char* shorty = gNativeBridgeArtCallbacks->getMethodShorty(env, mid);
if (strcmp(shorty, methods[i].signature) == 0) {
printf(" name:%s, signature:%s, shorty:%s.\n",
methods[i].name, nb_method->signature, shorty);
}
}
}
}
methods.release();
}
printf("%s called!\n", __FUNCTION__);
return fnPtr(vm, reserved);
}
static void trampoline_Java_Main_testFindClassOnAttachedNativeThread(JNIEnv* env, jclass klass) {
using FnPtr_t = void(*)(JNIEnv*, jclass);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>
(find_native_bridge_method("testFindClassOnAttachedNativeThread")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass);
}
static void trampoline_Java_Main_testFindFieldOnAttachedNativeThreadNative(JNIEnv* env,
jclass klass) {
using FnPtr_t = void(*)(JNIEnv*, jclass);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>
(find_native_bridge_method("testFindFieldOnAttachedNativeThreadNative")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass);
}
static void trampoline_Java_Main_testCallStaticVoidMethodOnSubClassNative(JNIEnv* env,
jclass klass) {
using FnPtr_t = void(*)(JNIEnv*, jclass);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>
(find_native_bridge_method("testCallStaticVoidMethodOnSubClassNative")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass);
}
static jobject trampoline_Java_Main_testGetMirandaMethodNative(JNIEnv* env, jclass klass) {
using FnPtr_t = jobject(*)(JNIEnv*, jclass);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>
(find_native_bridge_method("testGetMirandaMethodNative")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass);
}
static void trampoline_Java_Main_testNewStringObject(JNIEnv* env, jclass klass) {
using FnPtr_t = void(*)(JNIEnv*, jclass);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>
(find_native_bridge_method("testNewStringObject")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass);
}
static void trampoline_Java_Main_testZeroLengthByteBuffers(JNIEnv* env, jclass klass) {
using FnPtr_t = void(*)(JNIEnv*, jclass);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>
(find_native_bridge_method("testZeroLengthByteBuffers")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass);
}
static jbyte trampoline_Java_Main_byteMethod(JNIEnv* env, jclass klass, jbyte b1, jbyte b2,
jbyte b3, jbyte b4, jbyte b5, jbyte b6,
jbyte b7, jbyte b8, jbyte b9, jbyte b10) {
using FnPtr_t = jbyte(*)(JNIEnv*, jclass, jbyte, jbyte, jbyte, jbyte, jbyte, jbyte, jbyte, jbyte,
jbyte, jbyte);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>(find_native_bridge_method("byteMethod")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10);
}
static jshort trampoline_Java_Main_shortMethod(JNIEnv* env, jclass klass, jshort s1, jshort s2,
jshort s3, jshort s4, jshort s5, jshort s6,
jshort s7, jshort s8, jshort s9, jshort s10) {
using FnPtr_t = jshort(*)(JNIEnv*, jclass, jshort, jshort, jshort, jshort, jshort, jshort, jshort,
jshort, jshort, jshort);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>(find_native_bridge_method("shortMethod")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass, s1, s2, s3, s4, s5, s6, s7, s8, s9, s10);
}
static jboolean trampoline_Java_Main_booleanMethod(JNIEnv* env, jclass klass, jboolean b1,
jboolean b2, jboolean b3, jboolean b4,
jboolean b5, jboolean b6, jboolean b7,
jboolean b8, jboolean b9, jboolean b10) {
using FnPtr_t = jboolean(*)(JNIEnv*, jclass, jboolean, jboolean, jboolean, jboolean, jboolean,
jboolean, jboolean, jboolean, jboolean, jboolean);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>(find_native_bridge_method("booleanMethod")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10);
}
static jchar trampoline_Java_Main_charMethod(JNIEnv* env, jclass klass, jchar c1, jchar c2,
jchar c3, jchar c4, jchar c5, jchar c6,
jchar c7, jchar c8, jchar c9, jchar c10) {
using FnPtr_t = jchar(*)(JNIEnv*, jclass, jchar, jchar, jchar, jchar, jchar, jchar, jchar, jchar,
jchar, jchar);
FnPtr_t fnPtr = reinterpret_cast<FnPtr_t>(find_native_bridge_method("charMethod")->fnPtr);
printf("%s called!\n", __FUNCTION__);
return fnPtr(env, klass, c1, c2, c3, c4, c5, c6, c7, c8, c9, c10);
}
// This code is adapted from 004-SignalTest and causes a segfault.
char *go_away_compiler = nullptr;
[[ noreturn ]] static void test_sigaction_handler(int sig ATTRIBUTE_UNUSED,
siginfo_t* info ATTRIBUTE_UNUSED,
void* context ATTRIBUTE_UNUSED) {
printf("Should not reach the test sigaction handler.");
abort();
}
static void raise_sigsegv() {
#if defined(__arm__) || defined(__i386__) || defined(__aarch64__)
*go_away_compiler = 'a';
#elif defined(__x86_64__)
// Cause a SEGV using an instruction known to be 2 bytes long to account for hardcoded jump
// in the signal handler
asm volatile("movl $0, %%eax;" "movb %%ah, (%%rax);" : : : "%eax");
#else
// On other architectures we simulate SEGV.
kill(getpid(), SIGSEGV);
#endif
}
static jint trampoline_Java_Main_testSignal(JNIEnv*, jclass) {
// Install the sigaction handler above, which should *not* be reached as the native-bridge
// handler should be called first. Note: we won't chain at all, if we ever get here, we'll die.
struct sigaction tmp;
sigemptyset(&tmp.sa_mask);
tmp.sa_sigaction = test_sigaction_handler;
#if !defined(__APPLE__)
tmp.sa_restorer = nullptr;
#endif
// Test segv
sigaction(SIGSEGV, &tmp, nullptr);
raise_sigsegv();
// Test sigill
sigaction(SIGILL, &tmp, nullptr);
kill(getpid(), SIGILL);
#if defined(__BIONIC__)
// Do the same again, but with sigaction64.
struct sigaction64 tmp2;
sigemptyset64(&tmp2.sa_mask);
tmp2.sa_sigaction = test_sigaction_handler;
#if defined(SA_RESTORER)
tmp2.sa_restorer = nullptr;
#endif
sigaction64(SIGSEGV, &tmp2, nullptr);
sigaction64(SIGILL, &tmp2, nullptr);
#endif
// Reraise SIGSEGV/SIGILL even on non-bionic, so that the expected output is
// the same.
raise_sigsegv();
kill(getpid(), SIGILL);
return 1234;
}
// Status of the tricky control path of testSignalHandlerNotReturn.
//
// "kNone" is the default status except testSignalHandlerNotReturn,
// others are used by testSignalHandlerNotReturn.
enum class TestStatus {
kNone,
kRaiseFirst,
kHandleFirst,
kRaiseSecond,
kHandleSecond,
};
// State transition helper for testSignalHandlerNotReturn.
class SignalHandlerTestStatus {
public:
SignalHandlerTestStatus() : state_(TestStatus::kNone) {
}
TestStatus Get() {
return state_;
}
void Reset() {
Set(TestStatus::kNone);
}
void Set(TestStatus state) {
switch (state) {
case TestStatus::kNone:
AssertState(TestStatus::kHandleSecond);
break;
case TestStatus::kRaiseFirst:
AssertState(TestStatus::kNone);
break;
case TestStatus::kHandleFirst:
AssertState(TestStatus::kRaiseFirst);
break;
case TestStatus::kRaiseSecond:
AssertState(TestStatus::kHandleFirst);
break;
case TestStatus::kHandleSecond:
AssertState(TestStatus::kRaiseSecond);
break;
default:
printf("ERROR: unknown state\n");
abort();
}
state_ = state;
}
private:
TestStatus state_;
void AssertState(TestStatus expected) {
if (state_ != expected) {
printf("ERROR: unexpected state, was %d, expected %d\n", state_, expected);
}
}
};
static SignalHandlerTestStatus gSignalTestStatus;
// The context is used to jump out from signal handler.
static sigjmp_buf gSignalTestJmpBuf;
// Test whether NativeBridge can receive future signal when its handler doesn't return.
//
// Control path:
// 1. Raise first SIGSEGV in test function.
// 2. Raise another SIGSEGV in NativeBridge's signal handler which is handling
// the first SIGSEGV.
// 3. Expect that NativeBridge's signal handler invokes again. And jump back
// to test function in when handling second SIGSEGV.
// 4. Exit test.
//
// NOTE: sigchain should be aware that "special signal handler" may not return.
// Pay attention if this case fails.
static void trampoline_Java_Main_testSignalHandlerNotReturn(JNIEnv*, jclass) {
if (gSignalTestStatus.Get() != TestStatus::kNone) {
printf("ERROR: test already started?\n");
return;
}
printf("start testSignalHandlerNotReturn\n");
if (sigsetjmp(gSignalTestJmpBuf, 1) == 0) {
gSignalTestStatus.Set(TestStatus::kRaiseFirst);
printf("raising first SIGSEGV\n");
raise_sigsegv();
} else {
// jump to here from signal handler when handling second SIGSEGV.
if (gSignalTestStatus.Get() != TestStatus::kHandleSecond) {
printf("ERROR: not jump from second SIGSEGV?\n");
return;
}
gSignalTestStatus.Reset();
printf("back to test from signal handler via siglongjmp(), and done!\n");
}
}
// Signal handler for testSignalHandlerNotReturn.
// This handler won't return.
static bool NotReturnSignalHandler() {
if (gSignalTestStatus.Get() == TestStatus::kRaiseFirst) {
// handling first SIGSEGV
gSignalTestStatus.Set(TestStatus::kHandleFirst);
printf("handling first SIGSEGV, will raise another\n");
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGSEGV);
printf("unblock SIGSEGV in handler\n");
sigprocmask(SIG_UNBLOCK, &set, nullptr);
gSignalTestStatus.Set(TestStatus::kRaiseSecond);
printf("raising second SIGSEGV\n");
raise_sigsegv(); // raise second SIGSEGV
} else if (gSignalTestStatus.Get() == TestStatus::kRaiseSecond) {
// handling second SIGSEGV
gSignalTestStatus.Set(TestStatus::kHandleSecond);
printf("handling second SIGSEGV, will jump back to test function\n");
siglongjmp(gSignalTestJmpBuf, 1);
}
printf("ERROR: should not reach here!\n");
return false;
}
NativeBridgeMethod gNativeBridgeMethods[] = {
{ "JNI_OnLoad", "", true, nullptr,
reinterpret_cast<void*>(trampoline_JNI_OnLoad) },
{ "booleanMethod", "(ZZZZZZZZZZ)Z", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_booleanMethod) },
{ "byteMethod", "(BBBBBBBBBB)B", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_byteMethod) },
{ "charMethod", "(CCCCCCCCCC)C", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_charMethod) },
{ "shortMethod", "(SSSSSSSSSS)S", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_shortMethod) },
{ "testCallStaticVoidMethodOnSubClassNative", "()V", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testCallStaticVoidMethodOnSubClassNative) },
{ "testFindClassOnAttachedNativeThread", "()V", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testFindClassOnAttachedNativeThread) },
{ "testFindFieldOnAttachedNativeThreadNative", "()V", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testFindFieldOnAttachedNativeThreadNative) },
{ "testGetMirandaMethodNative", "()Ljava/lang/reflect/Method;", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testGetMirandaMethodNative) },
{ "testNewStringObject", "()V", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testNewStringObject) },
{ "testZeroLengthByteBuffers", "()V", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testZeroLengthByteBuffers) },
{ "testSignal", "()I", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testSignal) },
{ "testSignalHandlerNotReturn", "()V", true, nullptr,
reinterpret_cast<void*>(trampoline_Java_Main_testSignalHandlerNotReturn) },
};
static NativeBridgeMethod* find_native_bridge_method(const char *name) {
const char* pname = name;
if (strncmp(name, "Java_Main_", 10) == 0) {
pname += 10;
}
for (size_t i = 0; i < sizeof(gNativeBridgeMethods) / sizeof(gNativeBridgeMethods[0]); i++) {
if (strcmp(pname, gNativeBridgeMethods[i].name) == 0) {
return &gNativeBridgeMethods[i];
}
}
return nullptr;
}
// NativeBridgeCallbacks implementations
extern "C" bool native_bridge_initialize(const android::NativeBridgeRuntimeCallbacks* art_cbs,
const char* app_code_cache_dir,
const char* isa ATTRIBUTE_UNUSED) {
struct stat st;
if (app_code_cache_dir != nullptr) {
if (stat(app_code_cache_dir, &st) == 0) {
if (!S_ISDIR(st.st_mode)) {
printf("Code cache is not a directory.\n");
}
} else {
perror("Error when stat-ing the code_cache:");
}
}
if (art_cbs != nullptr) {
gNativeBridgeArtCallbacks = art_cbs;
printf("Native bridge initialized.\n");
}
return true;
}
extern "C" void* native_bridge_loadLibrary(const char* libpath, int flag) {
if (strstr(libpath, "libinvalid.so") != nullptr) {
printf("Was to load 'libinvalid.so', force fail.\n");
return nullptr;
}
size_t len = strlen(libpath);
char* tmp = new char[len + 10];
strncpy(tmp, libpath, len);
tmp[len - 3] = '2';
tmp[len - 2] = '.';
tmp[len - 1] = 's';
tmp[len] = 'o';
tmp[len + 1] = 0;
void* handle = dlopen(tmp, flag);
delete[] tmp;
if (handle == nullptr) {
printf("Handle = nullptr!\n");
printf("Was looking for %s.\n", libpath);
printf("Error = %s.\n", dlerror());
char cwd[1024] = {'\0'};
if (getcwd(cwd, sizeof(cwd)) != nullptr) {
printf("Current working dir: %s\n", cwd);
}
}
return handle;
}
extern "C" void* native_bridge_getTrampoline(void* handle, const char* name, const char* shorty,
uint32_t len ATTRIBUTE_UNUSED) {
printf("Getting trampoline for %s with shorty %s.\n", name, shorty);
// The name here is actually the JNI name, so we can directly do the lookup.
void* sym = dlsym(handle, name);
NativeBridgeMethod* method = find_native_bridge_method(name);
if (method == nullptr)
return nullptr;
method->fnPtr = sym;
return method->trampoline;
}
extern "C" bool native_bridge_isSupported(const char* libpath) {
printf("Checking for support.\n");
if (libpath == nullptr) {
return false;
}
// We don't want to hijack javacore. So we should get libarttest...
return strcmp(libpath, "libjavacore.so") != 0;
}
namespace android {
// Environment values required by the apps running with native bridge.
struct NativeBridgeRuntimeValues {
const char* os_arch;
const char* cpu_abi;
const char* cpu_abi2;
const char* *supported_abis;
int32_t abi_count;
};
} // namespace android
const char* supported_abis[] = {
"supported1", "supported2", "supported3"
};
const struct android::NativeBridgeRuntimeValues nb_env {
.os_arch = "os.arch",
.cpu_abi = "cpu_abi",
.cpu_abi2 = "cpu_abi2",
.supported_abis = supported_abis,
.abi_count = 3
};
extern "C" const struct android::NativeBridgeRuntimeValues* native_bridge_getAppEnv(
const char* abi) {
printf("Checking for getEnvValues.\n");
if (abi == nullptr) {
return nullptr;
}
return &nb_env;
}
// v2 parts.
extern "C" bool native_bridge_isCompatibleWith(uint32_t bridge_version ATTRIBUTE_UNUSED) {
return true;
}
#if defined(__i386__) || defined(__x86_64__)
#if defined(__APPLE__)
#define ucontext __darwin_ucontext
#if defined(__x86_64__)
// 64 bit mac build.
#define CTX_EIP uc_mcontext->__ss.__rip
#else
// 32 bit mac build.
#define CTX_EIP uc_mcontext->__ss.__eip
#endif
#elif defined(__x86_64__)
// 64 bit linux build.
#define CTX_EIP uc_mcontext.gregs[REG_RIP]
#else
// 32 bit linux build.
#define CTX_EIP uc_mcontext.gregs[REG_EIP]
#endif
#endif
static bool StandardSignalHandler(int sig, siginfo_t* info ATTRIBUTE_UNUSED,
void* context) {
if (sig == SIGSEGV) {
#if defined(__arm__)
struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
struct sigcontext *sc = reinterpret_cast<struct sigcontext*>(&uc->uc_mcontext);
sc->arm_pc += 2; // Skip instruction causing segv & sigill.
#elif defined(__aarch64__)
struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
struct sigcontext *sc = reinterpret_cast<struct sigcontext*>(&uc->uc_mcontext);
sc->pc += 4; // Skip instruction causing segv & sigill.
#elif defined(__i386__)
struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
uc->CTX_EIP += 3;
#elif defined(__x86_64__)
struct ucontext *uc = reinterpret_cast<struct ucontext*>(context);
uc->CTX_EIP += 2;
#else
UNUSED(context);
#endif
}
// We handled this...
return true;
}
// A placeholder special handler, continueing after the faulting location. This code comes from
// 004-SignalTest.
static bool nb_signalhandler(int sig, siginfo_t* info, void* context) {
printf("NB signal handler with signal %d.\n", sig);
if (gSignalTestStatus.Get() == TestStatus::kNone) {
return StandardSignalHandler(sig, info, context);
} else if (sig == SIGSEGV) {
return NotReturnSignalHandler();
} else {
printf("ERROR: should not reach here!\n");
return false;
}
}
static ::android::NativeBridgeSignalHandlerFn native_bridge_getSignalHandler(int signal) {
// Test segv for already claimed signal, and sigill for not claimed signal
if ((signal == SIGSEGV) || (signal == SIGILL)) {
return &nb_signalhandler;
}
return nullptr;
}
extern "C" int native_bridge_unloadLibrary(void* handle ATTRIBUTE_UNUSED) {
printf("dlclose() in native bridge.\n");
return 0;
}
extern "C" const char* native_bridge_getError() {
printf("getError() in native bridge.\n");
return "";
}
extern "C" bool native_bridge_isPathSupported(const char* library_path ATTRIBUTE_UNUSED) {
printf("Checking for path support in native bridge.\n");
return false;
}
extern "C" bool native_bridge_initAnonymousNamespace(const char* public_ns_sonames ATTRIBUTE_UNUSED,
const char* anon_ns_library_path ATTRIBUTE_UNUSED) {
printf("Initializing anonymous namespace in native bridge.\n");
return false;
}
extern "C" android::native_bridge_namespace_t*
native_bridge_createNamespace(const char* name ATTRIBUTE_UNUSED,
const char* ld_library_path ATTRIBUTE_UNUSED,
const char* default_library_path ATTRIBUTE_UNUSED,
uint64_t type ATTRIBUTE_UNUSED,
const char* permitted_when_isolated_path ATTRIBUTE_UNUSED,
android::native_bridge_namespace_t* parent_ns ATTRIBUTE_UNUSED) {
printf("Creating namespace in native bridge.\n");
return nullptr;
}
extern "C" bool native_bridge_linkNamespaces(android::native_bridge_namespace_t* from ATTRIBUTE_UNUSED,
android::native_bridge_namespace_t* to ATTRIBUTE_UNUSED,
const char* shared_libs_sonames ATTRIBUTE_UNUSED) {
printf("Linking namespaces in native bridge.\n");
return false;
}
extern "C" void* native_bridge_loadLibraryExt(const char* libpath ATTRIBUTE_UNUSED,
int flag ATTRIBUTE_UNUSED,
android::native_bridge_namespace_t* ns ATTRIBUTE_UNUSED) {
printf("Loading library with Extension in native bridge.\n");
return nullptr;
}
// "NativeBridgeItf" is effectively an API (it is the name of the symbol that will be loaded
// by the native bridge library).
android::NativeBridgeCallbacks NativeBridgeItf {
// v1
.version = 3,
.initialize = &native_bridge_initialize,
.loadLibrary = &native_bridge_loadLibrary,
.getTrampoline = &native_bridge_getTrampoline,
.isSupported = &native_bridge_isSupported,
.getAppEnv = &native_bridge_getAppEnv,
// v2
.isCompatibleWith = &native_bridge_isCompatibleWith,
.getSignalHandler = &native_bridge_getSignalHandler,
// v3
.unloadLibrary = &native_bridge_unloadLibrary,
.getError = &native_bridge_getError,
.isPathSupported = &native_bridge_isPathSupported,
.initAnonymousNamespace = &native_bridge_initAnonymousNamespace,
.createNamespace = &native_bridge_createNamespace,
.linkNamespaces = &native_bridge_linkNamespaces,
.loadLibraryExt = &native_bridge_loadLibraryExt
};