libbinder: move interruptableReadOrWrite to new file (9b40419e) · Commits · e / os / platform_frameworks_native

libs/binder/FdTrigger.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,7 @@
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/
		#pragma once

		#include <memory>

libs/binder/RpcTransportRaw.cpp

+5 −86

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@

		#include "FdTrigger.h"
		#include "RpcState.h"
		#include "RpcTransportUtils.h"

		namespace android {

		@@ -55,90 +56,6 @@ public:
		return OK;
		}

		template <typename SendOrReceive>
		status_t interruptableReadOrWrite(
		FdTrigger* fdTrigger, iovec* iovs, int niovs, SendOrReceive sendOrReceiveFun,
		const char* funName, int16_t event,
		const std::optional<android::base::function_ref<status_t()>>& altPoll) {
		MAYBE_WAIT_IN_FLAKE_MODE;

		if (niovs < 0) {
		return BAD_VALUE;
		}

		// Since we didn't poll, we need to manually check to see if it was triggered. Otherwise, we
		// may never know we should be shutting down.
		if (fdTrigger->isTriggered()) {
		return DEAD_OBJECT;
		}

		// If iovs has one or more empty vectors at the end and
		// we somehow advance past all the preceding vectors and
		// pass some or all of the empty ones to sendmsg/recvmsg,
		// the call will return processSize == 0. In that case
		// we should be returning OK but instead return DEAD_OBJECT.
		// To avoid this problem, we make sure here that the last
		// vector at iovs[niovs - 1] has a non-zero length.
		while (niovs > 0 && iovs[niovs - 1].iov_len == 0) {
		niovs--;
		}
		if (niovs == 0) {
		// The vectors are all empty, so we have nothing to send.
		return OK;
		}

		bool havePolled = false;
		while (true) {
		ssize_t processSize = sendOrReceiveFun(iovs, niovs);
		if (processSize < 0) {
		int savedErrno = errno;

		// Still return the error on later passes, since it would expose
		// a problem with polling
		if (havePolled \|\| (savedErrno != EAGAIN && savedErrno != EWOULDBLOCK)) {
		LOG_RPC_DETAIL("RpcTransport %s(): %s", funName, strerror(savedErrno));
		return -savedErrno;
		}
		} else if (processSize == 0) {
		return DEAD_OBJECT;
		} else {
		while (processSize > 0 && niovs > 0) {
		auto& iov = iovs[0];
		if (static_cast<size_t>(processSize) < iov.iov_len) {
		// Advance the base of the current iovec
		iov.iov_base = reinterpret_cast<char*>(iov.iov_base) + processSize;
		iov.iov_len -= processSize;
		break;
		}

		// The current iovec was fully written
		processSize -= iov.iov_len;
		iovs++;
		niovs--;
		}
		if (niovs == 0) {
		LOG_ALWAYS_FATAL_IF(processSize > 0,
		"Reached the end of iovecs "
		"with %zd bytes remaining",
		processSize);
		return OK;
		}
		}

		if (altPoll) {
		if (status_t status = (*altPoll)(); status != OK) return status;
		if (fdTrigger->isTriggered()) {
		return DEAD_OBJECT;
		}
		} else {
		if (status_t status = fdTrigger->triggerablePoll(mSocket.get(), event);
		status != OK)
		return status;
		if (!havePolled) havePolled = true;
		}
		}
		}

		status_t interruptableWriteFully(
		FdTrigger* fdTrigger, iovec* iovs, int niovs,
		const std::optional<android::base::function_ref<status_t()>>& altPoll,
		@@ -198,7 +115,8 @@ public:
		};
		return TEMP_FAILURE_RETRY(sendmsg(mSocket.get(), &msg, MSG_NOSIGNAL));
		};
		return interruptableReadOrWrite(fdTrigger, iovs, niovs, send, "sendmsg", POLLOUT, altPoll);
		return interruptableReadOrWrite(mSocket.get(), fdTrigger, iovs, niovs, send, "sendmsg",
		POLLOUT, altPoll);
		}

		status_t interruptableReadFully(
		@@ -255,7 +173,8 @@ public:
		};
		return TEMP_FAILURE_RETRY(recvmsg(mSocket.get(), &msg, MSG_NOSIGNAL));
		};
		return interruptableReadOrWrite(fdTrigger, iovs, niovs, recv, "recvmsg", POLLIN, altPoll);
		return interruptableReadOrWrite(mSocket.get(), fdTrigger, iovs, niovs, recv, "recvmsg",
		POLLIN, altPoll);
		}

		private:

libs/binder/RpcTransportUtils.h

0 → 100644

+109 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2022 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.
		*/
		#pragma once

		#include <android-base/unique_fd.h>
		#include <poll.h>

		#include "FdTrigger.h"
		#include "RpcState.h"

		namespace android {

		template <typename SendOrReceive>
		status_t interruptableReadOrWrite(
		int socketFd, FdTrigger* fdTrigger, iovec* iovs, int niovs, SendOrReceive sendOrReceiveFun,
		const char* funName, int16_t event,
		const std::optional<android::base::function_ref<status_t()>>& altPoll) {
		MAYBE_WAIT_IN_FLAKE_MODE;

		if (niovs < 0) {
		return BAD_VALUE;
		}

		// Since we didn't poll, we need to manually check to see if it was triggered. Otherwise, we
		// may never know we should be shutting down.
		if (fdTrigger->isTriggered()) {
		return DEAD_OBJECT;
		}

		// If iovs has one or more empty vectors at the end and
		// we somehow advance past all the preceding vectors and
		// pass some or all of the empty ones to sendmsg/recvmsg,
		// the call will return processSize == 0. In that case
		// we should be returning OK but instead return DEAD_OBJECT.
		// To avoid this problem, we make sure here that the last
		// vector at iovs[niovs - 1] has a non-zero length.
		while (niovs > 0 && iovs[niovs - 1].iov_len == 0) {
		niovs--;
		}
		if (niovs == 0) {
		// The vectors are all empty, so we have nothing to send.
		return OK;
		}

		bool havePolled = false;
		while (true) {
		ssize_t processSize = sendOrReceiveFun(iovs, niovs);
		if (processSize < 0) {
		int savedErrno = errno;

		// Still return the error on later passes, since it would expose
		// a problem with polling
		if (havePolled \|\| (savedErrno != EAGAIN && savedErrno != EWOULDBLOCK)) {
		LOG_RPC_DETAIL("RpcTransport %s(): %s", funName, strerror(savedErrno));
		return -savedErrno;
		}
		} else if (processSize == 0) {
		return DEAD_OBJECT;
		} else {
		while (processSize > 0 && niovs > 0) {
		auto& iov = iovs[0];
		if (static_cast<size_t>(processSize) < iov.iov_len) {
		// Advance the base of the current iovec
		iov.iov_base = reinterpret_cast<char*>(iov.iov_base) + processSize;
		iov.iov_len -= processSize;
		break;
		}

		// The current iovec was fully written
		processSize -= iov.iov_len;
		iovs++;
		niovs--;
		}
		if (niovs == 0) {
		LOG_ALWAYS_FATAL_IF(processSize > 0,
		"Reached the end of iovecs "
		"with %zd bytes remaining",
		processSize);
		return OK;
		}
		}

		if (altPoll) {
		if (status_t status = (*altPoll)(); status != OK) return status;
		if (fdTrigger->isTriggered()) {
		return DEAD_OBJECT;
		}
		} else {
		if (status_t status = fdTrigger->triggerablePoll(socketFd, event); status != OK)
		return status;
		if (!havePolled) havePolled = true;
		}
		}
		}

		} // namespace android