/*
* 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))
static bool gSingleProcess = false;
// ---------------------------------------------------------------------------
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()
{
if (gProcess != NULL) return gProcess;
AutoMutex _l(gProcessMutex);
if (gProcess == NULL) gProcess = new ProcessState;
return gProcess;
}
void ProcessState::setSingleProcess(bool singleProcess)
{
gSingleProcess = singleProcess;
}
void ProcessState::setContextObject(const sp<IBinder>& object)
{
setContextObject(object, String16("default"));
}
sp<IBinder> ProcessState::getContextObject(const sp<IBinder>& caller)
{
if (supportsProcesses()) {
return getStrongProxyForHandle(0);
} else {
return getContextObject(String16("default"), caller);
}
}
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) {
LOGE("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;
}
bool ProcessState::supportsProcesses() const
{
return mDriverFD >= 0;
}
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;
if (mDriverFD >= 0) {
int dummy = 0;
#if defined(HAVE_ANDROID_OS)
status_t result = ioctl(mDriverFD, BINDER_SET_CONTEXT_MGR, &dummy);
#else
status_t result = INVALID_OPERATION;
#endif
if (result == 0) {
mManagesContexts = true;
} else if (result == -1) {
mBinderContextCheckFunc = NULL;
mBinderContextUserData = NULL;
LOGE("Binder ioctl to become context manager failed: %s\n", strerror(errno));
}
} else {
// If there is no driver, our only world is the local
// process so we can always become the context manager there.
mManagesContexts = true;
}
}
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);
}
}
void ProcessState::spawnPooledThread(bool isMain)
{
if (mThreadPoolStarted) {
int32_t s = android_atomic_add(1, &mThreadPoolSeq);
char buf[32];
sprintf(buf, "Binder Thread #%d", s);
LOGV("Spawning new pooled thread, name=%s\n", buf);
sp<Thread> t = new PoolThread(isMain);
t->run(buf);
}
}
static int open_driver()
{
if (gSingleProcess) {
return -1;
}
int fd = open("/dev/binder", O_RDWR);
if (fd >= 0) {
fcntl(fd, F_SETFD, FD_CLOEXEC);
int vers;
#if defined(HAVE_ANDROID_OS)
status_t result = ioctl(fd, BINDER_VERSION, &vers);
#else
status_t result = -1;
errno = EPERM;
#endif
if (result == -1) {
LOGE("Binder ioctl to obtain version failed: %s", strerror(errno));
close(fd);
fd = -1;
}
if (result != 0 || vers != BINDER_CURRENT_PROTOCOL_VERSION) {
LOGE("Binder driver protocol does not match user space protocol!");
close(fd);
fd = -1;
}
#if defined(HAVE_ANDROID_OS)
size_t maxThreads = 15;
result = ioctl(fd, BINDER_SET_MAX_THREADS, &maxThreads);
if (result == -1) {
LOGE("Binder ioctl to set max threads failed: %s", strerror(errno));
}
#endif
} else {
LOGW("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*
LOGE("Using /dev/binder failed: unable to mmap transaction memory.\n");
close(mDriverFD);
mDriverFD = -1;
}
#else
mDriverFD = -1;
#endif
}
if (mDriverFD < 0) {
// Need to run without the driver, starting our own thread pool.
}
}
ProcessState::~ProcessState()
{
}
}; // namespace android