d7ac581045
Bug: webrtc:12338 Change-Id: Ifaad29ccb63b0f2f3aeefb77dae061ebc7f87e6c Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/227024 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Artem Titov <titovartem@webrtc.org> Cr-Commit-Position: refs/heads/master@{#34561}
134 lines
4.3 KiB
C++
134 lines
4.3 KiB
C++
/*
|
|
* Copyright 2018 The WebRTC project authors. All Rights Reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#include "sdk/android/src/jni/jvm.h"
|
|
|
|
#include <asm/unistd.h>
|
|
#include <pthread.h>
|
|
#include <sys/prctl.h>
|
|
#include <sys/syscall.h>
|
|
#include <unistd.h>
|
|
|
|
#include <string>
|
|
|
|
#include "rtc_base/checks.h"
|
|
|
|
namespace webrtc {
|
|
namespace jni {
|
|
|
|
static JavaVM* g_jvm = nullptr;
|
|
|
|
static pthread_once_t g_jni_ptr_once = PTHREAD_ONCE_INIT;
|
|
|
|
// Key for per-thread JNIEnv* data. Non-NULL in threads attached to `g_jvm` by
|
|
// AttachCurrentThreadIfNeeded(), NULL in unattached threads and threads that
|
|
// were attached by the JVM because of a Java->native call.
|
|
static pthread_key_t g_jni_ptr;
|
|
|
|
JavaVM* GetJVM() {
|
|
RTC_CHECK(g_jvm) << "JNI_OnLoad failed to run?";
|
|
return g_jvm;
|
|
}
|
|
|
|
// Return a |JNIEnv*| usable on this thread or NULL if this thread is detached.
|
|
JNIEnv* GetEnv() {
|
|
void* env = nullptr;
|
|
jint status = g_jvm->GetEnv(&env, JNI_VERSION_1_6);
|
|
RTC_CHECK(((env != nullptr) && (status == JNI_OK)) ||
|
|
((env == nullptr) && (status == JNI_EDETACHED)))
|
|
<< "Unexpected GetEnv return: " << status << ":" << env;
|
|
return reinterpret_cast<JNIEnv*>(env);
|
|
}
|
|
|
|
static void ThreadDestructor(void* prev_jni_ptr) {
|
|
// This function only runs on threads where `g_jni_ptr` is non-NULL, meaning
|
|
// we were responsible for originally attaching the thread, so are responsible
|
|
// for detaching it now. However, because some JVM implementations (notably
|
|
// Oracle's http://goo.gl/eHApYT) also use the pthread_key_create mechanism,
|
|
// the JVMs accounting info for this thread may already be wiped out by the
|
|
// time this is called. Thus it may appear we are already detached even though
|
|
// it was our responsibility to detach! Oh well.
|
|
if (!GetEnv())
|
|
return;
|
|
|
|
RTC_CHECK(GetEnv() == prev_jni_ptr)
|
|
<< "Detaching from another thread: " << prev_jni_ptr << ":" << GetEnv();
|
|
jint status = g_jvm->DetachCurrentThread();
|
|
RTC_CHECK(status == JNI_OK) << "Failed to detach thread: " << status;
|
|
RTC_CHECK(!GetEnv()) << "Detaching was a successful no-op???";
|
|
}
|
|
|
|
static void CreateJNIPtrKey() {
|
|
RTC_CHECK(!pthread_key_create(&g_jni_ptr, &ThreadDestructor))
|
|
<< "pthread_key_create";
|
|
}
|
|
|
|
jint InitGlobalJniVariables(JavaVM* jvm) {
|
|
RTC_CHECK(!g_jvm) << "InitGlobalJniVariables!";
|
|
g_jvm = jvm;
|
|
RTC_CHECK(g_jvm) << "InitGlobalJniVariables handed NULL?";
|
|
|
|
RTC_CHECK(!pthread_once(&g_jni_ptr_once, &CreateJNIPtrKey)) << "pthread_once";
|
|
|
|
JNIEnv* jni = nullptr;
|
|
if (jvm->GetEnv(reinterpret_cast<void**>(&jni), JNI_VERSION_1_6) != JNI_OK)
|
|
return -1;
|
|
|
|
return JNI_VERSION_1_6;
|
|
}
|
|
|
|
// Return thread ID as a string.
|
|
static std::string GetThreadId() {
|
|
char buf[21]; // Big enough to hold a kuint64max plus terminating NULL.
|
|
RTC_CHECK_LT(snprintf(buf, sizeof(buf), "%ld",
|
|
static_cast<long>(syscall(__NR_gettid))),
|
|
sizeof(buf))
|
|
<< "Thread id is bigger than uint64??";
|
|
return std::string(buf);
|
|
}
|
|
|
|
// Return the current thread's name.
|
|
static std::string GetThreadName() {
|
|
char name[17] = {0};
|
|
if (prctl(PR_GET_NAME, name) != 0)
|
|
return std::string("<noname>");
|
|
return std::string(name);
|
|
}
|
|
|
|
// Return a |JNIEnv*| usable on this thread. Attaches to `g_jvm` if necessary.
|
|
JNIEnv* AttachCurrentThreadIfNeeded() {
|
|
JNIEnv* jni = GetEnv();
|
|
if (jni)
|
|
return jni;
|
|
RTC_CHECK(!pthread_getspecific(g_jni_ptr))
|
|
<< "TLS has a JNIEnv* but not attached?";
|
|
|
|
std::string name(GetThreadName() + " - " + GetThreadId());
|
|
JavaVMAttachArgs args;
|
|
args.version = JNI_VERSION_1_6;
|
|
args.name = &name[0];
|
|
args.group = nullptr;
|
|
// Deal with difference in signatures between Oracle's jni.h and Android's.
|
|
#ifdef _JAVASOFT_JNI_H_ // Oracle's jni.h violates the JNI spec!
|
|
void* env = nullptr;
|
|
#else
|
|
JNIEnv* env = nullptr;
|
|
#endif
|
|
RTC_CHECK(!g_jvm->AttachCurrentThread(&env, &args))
|
|
<< "Failed to attach thread";
|
|
RTC_CHECK(env) << "AttachCurrentThread handed back NULL!";
|
|
jni = reinterpret_cast<JNIEnv*>(env);
|
|
RTC_CHECK(!pthread_setspecific(g_jni_ptr, jni)) << "pthread_setspecific";
|
|
return jni;
|
|
}
|
|
|
|
} // namespace jni
|
|
} // namespace webrtc
|