Merge "libbinder: Handle transaction failures correctly" (823fa55a) · Commits · e / os / android_frameworks_native-old

include/binder/Status.h

+25 −16

Original line number	Diff line number	Diff line
		@@ -60,31 +60,31 @@ public:
		EX_ILLEGAL_STATE = -5,
		EX_NETWORK_MAIN_THREAD = -6,
		EX_UNSUPPORTED_OPERATION = -7,
		EX_TRANSACTION_FAILED = -8,

		// This is special and Java specific; see Parcel.java.
		EX_HAS_REPLY_HEADER = -128,
		// This is special, and indicates to C++ binder proxies that the
		// transaction has failed at a low level.
		EX_TRANSACTION_FAILED = -129,
		};

		// A more readable alias for the default constructor.
		static Status ok();
		// Allow authors to explicitly pick whether their integer is a status_t or
		// exception code.
		static Status fromExceptionCode(int32_t exception_code);
		static Status fromExceptionCode(int32_t exceptionCode);
		static Status fromExceptionCode(int32_t exceptionCode,
		const String8& message);
		static Status fromStatusT(status_t status);
		// A more readable alias for the default constructor.
		static Status ok();

		Status() = default;
		Status(int32_t exception_code, const String8& message);
		Status(int32_t exception_code, const char* message);

		~Status() = default;

		// Status objects are copyable and contain just simple data.
		Status(const Status& status) = default;
		Status(Status&& status) = default;
		Status& operator=(const Status& status) = default;

		~Status() = default;

		// Bear in mind that if the client or service is a Java endpoint, this
		// is not the logic which will provide/interpret the data here.
		status_t readFromParcel(const Parcel& parcel);
		@@ -92,16 +92,17 @@ public:

		// Set one of the pre-defined exception types defined above.
		void setException(int32_t ex, const String8& message);
		// A few of the status_t values map to exception codes, but most of them
		// simply map to "transaction failed."
		// Setting a \|status\| != OK causes generated code to return \|status\|
		// from Binder transactions, rather than writing an exception into the
		// reply Parcel.
		void setFromStatusT(status_t status);

		// Get information about an exception.
		// Any argument may be given as nullptr.
		void getException(int32_t* returned_exception,
		String8* returned_message) const;
		int32_t exceptionCode() const { return mException; }
		const String8& exceptionMessage() const { return mMessage; }
		status_t transactionError() const {
		return mException == EX_TRANSACTION_FAILED ? mErrorCode : OK;
		}

		bool isOk() const { return mException == EX_NONE; }

		@@ -109,9 +110,17 @@ public:
		String8 toString8() const;

		private:
		// We always write \|mException\| to the parcel.
		// If \|mException\| != EX_NONE, we write message as well.
		Status(int32_t exception_code);
		Status(int32_t exception_code, const String8& message);

		// If \|mException\| == EX_TRANSACTION_FAILED, generated code will return
		// \|mErrorCode\| as the result of the transaction rather than write an
		// exception to the reply parcel.
		//
		// Otherwise, we always write \|mException\| to the parcel.
		// If \|mException\| != EX_NONE, we write \|mMessage\| as well.
		int32_t mException = EX_NONE;
		int32_t mErrorCode = 0;
		String8 mMessage;
		}; // class Status

libs/binder/Status.cpp

+34 −37

Original line number	Diff line number	Diff line
		@@ -19,8 +19,17 @@
		namespace android {
		namespace binder {

		Status Status::fromExceptionCode(int32_t exception_code) {
		return Status(exception_code, "");
		Status Status::ok() {
		return Status();
		}

		Status Status::fromExceptionCode(int32_t exceptionCode) {
		return Status(exceptionCode);
		}

		Status Status::fromExceptionCode(int32_t exceptionCode,
		const String8& message) {
		return Status(exceptionCode, message);
		}

		Status Status::fromStatusT(status_t status) {
		@@ -29,16 +38,9 @@ Status Status::fromStatusT(status_t status) {
		return ret;
		}

		Status Status::ok() {
		return Status();
		}

		Status::Status(int32_t exception_code, const String8& message)
		: mException(exception_code),
		mMessage(message) {}

		Status::Status(int32_t exception_code, const char* message)
		: mException(exception_code),
		Status::Status(int32_t exceptionCode) : mException(exceptionCode) {}
		Status::Status(int32_t exceptionCode, const String8& message)
		: mException(exceptionCode),
		mMessage(message) {}

		status_t Status::readFromParcel(const Parcel& parcel) {
		@@ -69,12 +71,24 @@ status_t Status::readFromParcel(const Parcel& parcel) {
		}

		// The remote threw an exception. Get the message back.
		mMessage = String8(parcel.readString16());
		String16 message;
		status = parcel.readString16(&message);
		if (status != OK) {
		setFromStatusT(status);
		return status;
		}
		mMessage = String8(message);

		return status;
		}

		status_t Status::writeToParcel(Parcel* parcel) const {
		// Something really bad has happened, and we're not going to even
		// try returning rich error data.
		if (mException == EX_TRANSACTION_FAILED) {
		return mErrorCode;
		}

		status_t status = parcel->writeInt32(mException);
		if (status != OK) { return status; }
		if (mException == EX_NONE) {
		@@ -86,43 +100,26 @@ status_t Status::writeToParcel(Parcel* parcel) const {
		}

		void Status::setFromStatusT(status_t status) {
		switch (status) {
		case NO_ERROR:
		mException = EX_NONE;
		mException = (status == NO_ERROR) ? EX_NONE : EX_TRANSACTION_FAILED;
		mErrorCode = status;
		mMessage.clear();
		break;
		case UNEXPECTED_NULL:
		mException = EX_NULL_POINTER;
		mMessage.setTo("Unexpected null reference in Parcel");
		break;
		default:
		mException = EX_TRANSACTION_FAILED;
		mMessage.setTo("Transaction failed");
		break;
		}
		}

		void Status::setException(int32_t ex, const String8& message) {
		mException = ex;
		mErrorCode = NO_ERROR; // an exception, not a transaction failure.
		mMessage.setTo(message);
		}

		void Status::getException(int32_t* returned_exception,
		String8* returned_message) const {
		if (returned_exception) {
		*returned_exception = mException;
		}
		if (returned_message) {
		returned_message->setTo(mMessage);
		}
		}

		String8 Status::toString8() const {
		String8 ret;
		if (mException == EX_NONE) {
		ret.append("No error");
		} else {
		ret.appendFormat("Status(%d): '", mException);
		if (mException == EX_TRANSACTION_FAILED) {
		ret.appendFormat("%d: ", mErrorCode);
		}
		ret.append(String8(mMessage));
		ret.append("'");
		}