libs/binder/ProcessState.cpp - platform/frameworks/native - Git at Google

 /*
  * Copyright (C) 2005 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.
  */

 #define LOG_TAG "ProcessState"

 #include <cutils/process_name.h>

 #include <binder/ProcessState.h>

 #include <utils/Atomic.h>
 #include <binder/BpBinder.h>
 #include <binder/IPCThreadState.h>
 #include <utils/Log.h>
 #include <utils/String8.h>
 #include <binder/IServiceManager.h>
 #include <utils/String8.h>
 #include <utils/threads.h>

 #include <private/binder/binder_module.h>
 #include <private/binder/Static.h>

 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <sys/stat.h>

 #define BINDER_VM_SIZE ((1*1024*1024) - (4096 *2))


 // ---------------------------------------------------------------------------

 namespace android {

 // Global variables
 int                 mArgC;
 const char* const*  mArgV;
 int                 mArgLen;

 class PoolThread : public Thread
 {
 public:
     PoolThread(bool isMain)
         : mIsMain(isMain)
     {
     }

 protected:
     virtual bool threadLoop()
     {
         IPCThreadState::self()->joinThreadPool(mIsMain);
         return false;
     }

     const bool mIsMain;
 };

 sp<ProcessState> ProcessState::self()
 {
     Mutex::Autolock _l(gProcessMutex);
     if (gProcess != NULL) {
         return gProcess;
     }
     gProcess = new ProcessState;
     return gProcess;
 }

 void ProcessState::setContextObject(const sp<IBinder>& object)
 {
     setContextObject(object, String16("default"));
 }

 sp<IBinder> ProcessState::getContextObject(const sp<IBinder>& caller)
 {
     return getStrongProxyForHandle(0);
 }

 void ProcessState::setContextObject(const sp<IBinder>& object, const String16& name)
 {
     AutoMutex _l(mLock);
     mContexts.add(name, object);
 }

 sp<IBinder> ProcessState::getContextObject(const String16& name, const sp<IBinder>& caller)
 {
     mLock.lock();
     sp<IBinder> object(
         mContexts.indexOfKey(name) >= 0 ? mContexts.valueFor(name) : NULL);
     mLock.unlock();

     //printf("Getting context object %s for %p\n", String8(name).string(), caller.get());

     if (object != NULL) return object;

     // Don't attempt to retrieve contexts if we manage them
     if (mManagesContexts) {
         ALOGE("getContextObject(%s) failed, but we manage the contexts!\n",
             String8(name).string());
         return NULL;
     }

     IPCThreadState* ipc = IPCThreadState::self();
     {
         Parcel data, reply;
         // no interface token on this magic transaction
         data.writeString16(name);
         data.writeStrongBinder(caller);
         status_t result = ipc->transact(0 /*magic*/, 0, data, &reply, 0);
         if (result == NO_ERROR) {
             object = reply.readStrongBinder();
         }
     }

     ipc->flushCommands();

     if (object != NULL) setContextObject(object, name);
     return object;
 }

 void ProcessState::startThreadPool()
 {
     AutoMutex _l(mLock);
     if (!mThreadPoolStarted) {
         mThreadPoolStarted = true;
         spawnPooledThread(true);
     }
 }

 bool ProcessState::isContextManager(void) const
 {
     return mManagesContexts;
 }

 bool ProcessState::becomeContextManager(context_check_func checkFunc, void* userData)
 {
     if (!mManagesContexts) {
         AutoMutex _l(mLock);
         mBinderContextCheckFunc = checkFunc;
         mBinderContextUserData = userData;

         int dummy = 0;
         status_t result = ioctl(mDriverFD, BINDER_SET_CONTEXT_MGR, &dummy);
         if (result == 0) {
             mManagesContexts = true;
         } else if (result == -1) {
             mBinderContextCheckFunc = NULL;
             mBinderContextUserData = NULL;
             ALOGE("Binder ioctl to become context manager failed: %s\n", strerror(errno));
         }
     }
     return mManagesContexts;
 }

 ProcessState::handle_entry* ProcessState::lookupHandleLocked(int32_t handle)
 {
     const size_t N=mHandleToObject.size();
     if (N <= (size_t)handle) {
         handle_entry e;
         e.binder = NULL;
         e.refs = NULL;
         status_t err = mHandleToObject.insertAt(e, N, handle+1-N);
         if (err < NO_ERROR) return NULL;
     }
     return &mHandleToObject.editItemAt(handle);
 }

 sp<IBinder> ProcessState::getStrongProxyForHandle(int32_t handle)
 {
     sp<IBinder> result;

     AutoMutex _l(mLock);

     handle_entry* e = lookupHandleLocked(handle);

     if (e != NULL) {
         // We need to create a new BpBinder if there isn't currently one, OR we
         // are unable to acquire a weak reference on this current one.  See comment
         // in getWeakProxyForHandle() for more info about this.
         IBinder* b = e->binder;
         if (b == NULL || !e->refs->attemptIncWeak(this)) {
             b = new BpBinder(handle);
             e->binder = b;
             if (b) e->refs = b->getWeakRefs();
             result = b;
         } else {
             // This little bit of nastyness is to allow us to add a primary
             // reference to the remote proxy when this team doesn't have one
             // but another team is sending the handle to us.
             result.force_set(b);
             e->refs->decWeak(this);
         }
     }

     return result;
 }

 wp<IBinder> ProcessState::getWeakProxyForHandle(int32_t handle)
 {
     wp<IBinder> result;

     AutoMutex _l(mLock);

     handle_entry* e = lookupHandleLocked(handle);

     if (e != NULL) {
         // We need to create a new BpBinder if there isn't currently one, OR we
         // are unable to acquire a weak reference on this current one.  The
         // attemptIncWeak() is safe because we know the BpBinder destructor will always
         // call expungeHandle(), which acquires the same lock we are holding now.
         // We need to do this because there is a race condition between someone
         // releasing a reference on this BpBinder, and a new reference on its handle
         // arriving from the driver.
         IBinder* b = e->binder;
         if (b == NULL || !e->refs->attemptIncWeak(this)) {
             b = new BpBinder(handle);
             result = b;
             e->binder = b;
             if (b) e->refs = b->getWeakRefs();
         } else {
             result = b;
             e->refs->decWeak(this);
         }
     }

     return result;
 }

 void ProcessState::expungeHandle(int32_t handle, IBinder* binder)
 {
     AutoMutex _l(mLock);

     handle_entry* e = lookupHandleLocked(handle);

     // This handle may have already been replaced with a new BpBinder
     // (if someone failed the AttemptIncWeak() above); we don't want
     // to overwrite it.
     if (e && e->binder == binder) e->binder = NULL;
 }

 void ProcessState::setArgs(int argc, const char* const argv[])
 {
     mArgC = argc;
     mArgV = (const char **)argv;

     mArgLen = 0;
     for (int i=0; i<argc; i++) {
         mArgLen += strlen(argv[i]) + 1;
     }
     mArgLen--;
 }

 int ProcessState::getArgC() const
 {
     return mArgC;
 }

 const char* const* ProcessState::getArgV() const
 {
     return mArgV;
 }

 void ProcessState::setArgV0(const char* txt)
 {
     if (mArgV != NULL) {
         strncpy((char*)mArgV[0], txt, mArgLen);
         set_process_name(txt);
     }
 }

 String8 ProcessState::makeBinderThreadName() {
     int32_t s = android_atomic_add(1, &mThreadPoolSeq);
     String8 name;
     name.appendFormat("Binder_%X", s);
     return name;
 }

 void ProcessState::spawnPooledThread(bool isMain)
 {
     if (mThreadPoolStarted) {
         String8 name = makeBinderThreadName();
         ALOGV("Spawning new pooled thread, name=%s\n", name.string());
         sp<Thread> t = new PoolThread(isMain);
         t->run(name.string());
     }
 }

 status_t ProcessState::setThreadPoolMaxThreadCount(size_t maxThreads) {
     status_t result = NO_ERROR;
     if (ioctl(mDriverFD, BINDER_SET_MAX_THREADS, &maxThreads) == -1) {
         result = -errno;
         ALOGE("Binder ioctl to set max threads failed: %s", strerror(-result));
     }
     return result;
 }

 void ProcessState::giveThreadPoolName() {
     androidSetThreadName( makeBinderThreadName().string() );
 }

 static int open_driver()
 {
     int fd = open("/dev/binder", O_RDWR);
     if (fd >= 0) {
         fcntl(fd, F_SETFD, FD_CLOEXEC);
         int vers;
         status_t result = ioctl(fd, BINDER_VERSION, &vers);
         if (result == -1) {
             ALOGE("Binder ioctl to obtain version failed: %s", strerror(errno));
             close(fd);
             fd = -1;
         }
         if (result != 0 || vers != BINDER_CURRENT_PROTOCOL_VERSION) {
             ALOGE("Binder driver protocol does not match user space protocol!");
             close(fd);
             fd = -1;
         }
         size_t maxThreads = 15;
         result = ioctl(fd, BINDER_SET_MAX_THREADS, &maxThreads);
         if (result == -1) {
             ALOGE("Binder ioctl to set max threads failed: %s", strerror(errno));
         }
     } else {
         ALOGW("Opening '/dev/binder' failed: %s\n", strerror(errno));
     }
     return fd;
 }

 ProcessState::ProcessState()
     : mDriverFD(open_driver())
     , mVMStart(MAP_FAILED)
     , mManagesContexts(false)
     , mBinderContextCheckFunc(NULL)
     , mBinderContextUserData(NULL)
     , mThreadPoolStarted(false)
     , mThreadPoolSeq(1)
 {
     if (mDriverFD >= 0) {
         // XXX Ideally, there should be a specific define for whether we
         // have mmap (or whether we could possibly have the kernel module
         // availabla).
 #if !defined(HAVE_WIN32_IPC)
         // mmap the binder, providing a chunk of virtual address space to receive transactions.
         mVMStart = mmap(0, BINDER_VM_SIZE, PROT_READ, MAP_PRIVATE | MAP_NORESERVE, mDriverFD, 0);
         if (mVMStart == MAP_FAILED) {
             // *sigh*
             ALOGE("Using /dev/binder failed: unable to mmap transaction memory.\n");
             close(mDriverFD);
             mDriverFD = -1;
         }
 #else
         mDriverFD = -1;
 #endif
     }

     LOG_ALWAYS_FATAL_IF(mDriverFD < 0, "Binder driver could not be opened.  Terminating.");
 }

 ProcessState::~ProcessState()
 {
 }

 }; // namespace android
	/*
	* Copyright (C) 2005 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.
	*/

	#define LOG_TAG "ProcessState"

	#include <cutils/process_name.h>

	#include <binder/ProcessState.h>

	#include <utils/Atomic.h>
	#include <binder/BpBinder.h>
	#include <binder/IPCThreadState.h>
	#include <utils/Log.h>
	#include <utils/String8.h>
	#include <binder/IServiceManager.h>
	#include <utils/String8.h>
	#include <utils/threads.h>

	#include <private/binder/binder_module.h>
	#include <private/binder/Static.h>

	#include <errno.h>
	#include <fcntl.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <sys/ioctl.h>
	#include <sys/mman.h>
	#include <sys/stat.h>

	#define BINDER_VM_SIZE ((110241024) - (4096 *2))


	// ---------------------------------------------------------------------------

	namespace android {

	// Global variables
	int mArgC;
	const char* const* mArgV;
	int mArgLen;

	class PoolThread : public Thread
	{
	public:
	PoolThread(bool isMain)
	: mIsMain(isMain)
	{
	}

	protected:
	virtual bool threadLoop()
	{
	IPCThreadState::self()->joinThreadPool(mIsMain);
	return false;
	}

	const bool mIsMain;
	};

	sp<ProcessState> ProcessState::self()
	{
	Mutex::Autolock _l(gProcessMutex);
	if (gProcess != NULL) {
	return gProcess;
	}
	gProcess = new ProcessState;
	return gProcess;
	}

	void ProcessState::setContextObject(const sp<IBinder>& object)
	{
	setContextObject(object, String16("default"));
	}

	sp<IBinder> ProcessState::getContextObject(const sp<IBinder>& caller)
	{
	return getStrongProxyForHandle(0);
	}

	void ProcessState::setContextObject(const sp<IBinder>& object, const String16& name)
	{
	AutoMutex _l(mLock);
	mContexts.add(name, object);
	}

	sp<IBinder> ProcessState::getContextObject(const String16& name, const sp<IBinder>& caller)
	{
	mLock.lock();
	sp<IBinder> object(
	mContexts.indexOfKey(name) >= 0 ? mContexts.valueFor(name) : NULL);
	mLock.unlock();

	//printf("Getting context object %s for %p\n", String8(name).string(), caller.get());

	if (object != NULL) return object;

	// Don't attempt to retrieve contexts if we manage them
	if (mManagesContexts) {
	ALOGE("getContextObject(%s) failed, but we manage the contexts!\n",
	String8(name).string());
	return NULL;
	}

	IPCThreadState* ipc = IPCThreadState::self();
	{
	Parcel data, reply;
	// no interface token on this magic transaction
	data.writeString16(name);
	data.writeStrongBinder(caller);
	status_t result = ipc->transact(0 /magic/, 0, data, &reply, 0);
	if (result == NO_ERROR) {
	object = reply.readStrongBinder();
	}
	}

	ipc->flushCommands();

	if (object != NULL) setContextObject(object, name);
	return object;
	}

	void ProcessState::startThreadPool()
	{
	AutoMutex _l(mLock);
	if (!mThreadPoolStarted) {
	mThreadPoolStarted = true;
	spawnPooledThread(true);
	}
	}

	bool ProcessState::isContextManager(void) const
	{
	return mManagesContexts;
	}

	bool ProcessState::becomeContextManager(context_check_func checkFunc, void* userData)
	{
	if (!mManagesContexts) {
	AutoMutex _l(mLock);
	mBinderContextCheckFunc = checkFunc;
	mBinderContextUserData = userData;

	int dummy = 0;
	status_t result = ioctl(mDriverFD, BINDER_SET_CONTEXT_MGR, &dummy);
	if (result == 0) {
	mManagesContexts = true;
	} else if (result == -1) {
	mBinderContextCheckFunc = NULL;
	mBinderContextUserData = NULL;
	ALOGE("Binder ioctl to become context manager failed: %s\n", strerror(errno));
	}
	}
	return mManagesContexts;
	}

	ProcessState::handle_entry* ProcessState::lookupHandleLocked(int32_t handle)
	{
	const size_t N=mHandleToObject.size();
	if (N <= (size_t)handle) {
	handle_entry e;
	e.binder = NULL;
	e.refs = NULL;
	status_t err = mHandleToObject.insertAt(e, N, handle+1-N);
	if (err < NO_ERROR) return NULL;
	}
	return &mHandleToObject.editItemAt(handle);
	}

	sp<IBinder> ProcessState::getStrongProxyForHandle(int32_t handle)
	{
	sp<IBinder> result;

	AutoMutex _l(mLock);

	handle_entry* e = lookupHandleLocked(handle);

	if (e != NULL) {
	// We need to create a new BpBinder if there isn't currently one, OR we
	// are unable to acquire a weak reference on this current one. See comment
	// in getWeakProxyForHandle() for more info about this.
	IBinder* b = e->binder;
	if (b == NULL \|\| !e->refs->attemptIncWeak(this)) {
	b = new BpBinder(handle);
	e->binder = b;
	if (b) e->refs = b->getWeakRefs();
	result = b;
	} else {
	// This little bit of nastyness is to allow us to add a primary
	// reference to the remote proxy when this team doesn't have one
	// but another team is sending the handle to us.
	result.force_set(b);
	e->refs->decWeak(this);
	}
	}

	return result;
	}

	wp<IBinder> ProcessState::getWeakProxyForHandle(int32_t handle)
	{
	wp<IBinder> result;

	AutoMutex _l(mLock);

	handle_entry* e = lookupHandleLocked(handle);

	if (e != NULL) {
	// We need to create a new BpBinder if there isn't currently one, OR we
	// are unable to acquire a weak reference on this current one. The
	// attemptIncWeak() is safe because we know the BpBinder destructor will always
	// call expungeHandle(), which acquires the same lock we are holding now.
	// We need to do this because there is a race condition between someone
	// releasing a reference on this BpBinder, and a new reference on its handle
	// arriving from the driver.
	IBinder* b = e->binder;
	if (b == NULL \|\| !e->refs->attemptIncWeak(this)) {
	b = new BpBinder(handle);
	result = b;
	e->binder = b;
	if (b) e->refs = b->getWeakRefs();
	} else {
	result = b;
	e->refs->decWeak(this);
	}
	}

	return result;
	}

	void ProcessState::expungeHandle(int32_t handle, IBinder* binder)
	{
	AutoMutex _l(mLock);

	handle_entry* e = lookupHandleLocked(handle);

	// This handle may have already been replaced with a new BpBinder
	// (if someone failed the AttemptIncWeak() above); we don't want
	// to overwrite it.
	if (e && e->binder == binder) e->binder = NULL;
	}

	void ProcessState::setArgs(int argc, const char* const argv[])
	{
	mArgC = argc;
	mArgV = (const char **)argv;

	mArgLen = 0;
	for (int i=0; i<argc; i++) {
	mArgLen += strlen(argv[i]) + 1;
	}
	mArgLen--;
	}

	int ProcessState::getArgC() const
	{
	return mArgC;
	}

	const char* const* ProcessState::getArgV() const
	{
	return mArgV;
	}

	void ProcessState::setArgV0(const char* txt)
	{
	if (mArgV != NULL) {
	strncpy((char*)mArgV[0], txt, mArgLen);
	set_process_name(txt);
	}
	}

	String8 ProcessState::makeBinderThreadName() {
	int32_t s = android_atomic_add(1, &mThreadPoolSeq);
	String8 name;
	name.appendFormat("Binder_%X", s);
	return name;
	}

	void ProcessState::spawnPooledThread(bool isMain)
	{
	if (mThreadPoolStarted) {
	String8 name = makeBinderThreadName();
	ALOGV("Spawning new pooled thread, name=%s\n", name.string());
	sp<Thread> t = new PoolThread(isMain);
	t->run(name.string());
	}
	}

	status_t ProcessState::setThreadPoolMaxThreadCount(size_t maxThreads) {
	status_t result = NO_ERROR;
	if (ioctl(mDriverFD, BINDER_SET_MAX_THREADS, &maxThreads) == -1) {
	result = -errno;
	ALOGE("Binder ioctl to set max threads failed: %s", strerror(-result));
	}
	return result;
	}

	void ProcessState::giveThreadPoolName() {
	androidSetThreadName( makeBinderThreadName().string() );
	}

	static int open_driver()
	{
	int fd = open("/dev/binder", O_RDWR);
	if (fd >= 0) {
	fcntl(fd, F_SETFD, FD_CLOEXEC);
	int vers;
	status_t result = ioctl(fd, BINDER_VERSION, &vers);
	if (result == -1) {
	ALOGE("Binder ioctl to obtain version failed: %s", strerror(errno));
	close(fd);
	fd = -1;
	}
	if (result != 0 \|\| vers != BINDER_CURRENT_PROTOCOL_VERSION) {
	ALOGE("Binder driver protocol does not match user space protocol!");
	close(fd);
	fd = -1;
	}
	size_t maxThreads = 15;
	result = ioctl(fd, BINDER_SET_MAX_THREADS, &maxThreads);
	if (result == -1) {
	ALOGE("Binder ioctl to set max threads failed: %s", strerror(errno));
	}
	} else {
	ALOGW("Opening '/dev/binder' failed: %s\n", strerror(errno));
	}
	return fd;
	}

	ProcessState::ProcessState()
	: mDriverFD(open_driver())
	, mVMStart(MAP_FAILED)
	, mManagesContexts(false)
	, mBinderContextCheckFunc(NULL)
	, mBinderContextUserData(NULL)
	, mThreadPoolStarted(false)
	, mThreadPoolSeq(1)
	{
	if (mDriverFD >= 0) {
	// XXX Ideally, there should be a specific define for whether we
	// have mmap (or whether we could possibly have the kernel module
	// availabla).
	#if !defined(HAVE_WIN32_IPC)
	// mmap the binder, providing a chunk of virtual address space to receive transactions.
	mVMStart = mmap(0, BINDER_VM_SIZE, PROT_READ, MAP_PRIVATE \| MAP_NORESERVE, mDriverFD, 0);
	if (mVMStart == MAP_FAILED) {
	// sigh
	ALOGE("Using /dev/binder failed: unable to mmap transaction memory.\n");
	close(mDriverFD);
	mDriverFD = -1;
	}
	#else
	mDriverFD = -1;
	#endif
	}

	LOG_ALWAYS_FATAL_IF(mDriverFD < 0, "Binder driver could not be opened. Terminating.");
	}

	ProcessState::~ProcessState()
	{
	}

	}; // namespace android