adb: move fdevent implementation out to a separate file.
Test: mma
Change-Id: I8af945b9ae0accac75fa93c538e44cbab357bb5d
diff --git a/adb/Android.bp b/adb/Android.bp
index 583248b..f6aede8 100644
--- a/adb/Android.bp
+++ b/adb/Android.bp
@@ -125,6 +125,7 @@
"adb_unique_fd.cpp",
"adb_utils.cpp",
"fdevent/fdevent.cpp",
+ "fdevent/fdevent_poll.cpp",
"services.cpp",
"sockets.cpp",
"socket_spec.cpp",
diff --git a/adb/fdevent/fdevent.cpp b/adb/fdevent/fdevent.cpp
index eda9463..82bb0a2 100644
--- a/adb/fdevent/fdevent.cpp
+++ b/adb/fdevent/fdevent.cpp
@@ -1,64 +1,31 @@
-/* http://frotznet.googlecode.com/svn/trunk/utils/fdevent.c
-**
-** Copyright 2006, Brian Swetland <swetland@frotz.net>
-**
-** 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.
-*/
+/*
+ * Copyright 2006, Brian Swetland <swetland@frotz.net>
+ *
+ * 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 TRACE_TAG FDEVENT
#include "sysdeps.h"
-#include "fdevent.h"
-#include <fcntl.h>
#include <inttypes.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <atomic>
-#include <deque>
-#include <functional>
-#include <list>
-#include <mutex>
-#include <optional>
-#include <unordered_map>
-#include <utility>
-#include <variant>
-#include <vector>
-
-#include <android-base/chrono_utils.h>
-#include <android-base/file.h>
-#include <android-base/logging.h>
#include <android-base/stringprintf.h>
-#include <android-base/thread_annotations.h>
-#include <android-base/threads.h>
-#include "adb_io.h"
-#include "adb_trace.h"
-#include "adb_unique_fd.h"
-#include "adb_utils.h"
-#include "sysdeps/chrono.h"
+#include "fdevent.h"
+#include "fdevent_poll.h"
-#define FDE_EVENTMASK 0x00ff
-#define FDE_STATEMASK 0xff00
-
-#define FDE_ACTIVE 0x0100
-#define FDE_PENDING 0x0200
-#define FDE_CREATED 0x0400
-
-static std::string dump_fde(const fdevent* fde) {
+std::string dump_fde(const fdevent* fde) {
std::string state;
if (fde->state & FDE_ACTIVE) {
state += "A";
@@ -82,486 +49,12 @@
state.c_str());
}
-struct PollNode {
- fdevent* fde;
- adb_pollfd pollfd;
-
- explicit PollNode(fdevent* fde) : fde(fde) {
- memset(&pollfd, 0, sizeof(pollfd));
- pollfd.fd = fde->fd.get();
-
-#if defined(__linux__)
- // Always enable POLLRDHUP, so the host server can take action when some clients disconnect.
- // Then we can avoid leaving many sockets in CLOSE_WAIT state. See http://b/23314034.
- pollfd.events = POLLRDHUP;
-#endif
- }
-};
-
-struct fdevent_context_poll : public fdevent_context {
- virtual ~fdevent_context_poll() = default;
-
- virtual fdevent* Create(unique_fd fd, std::variant<fd_func, fd_func2> func, void* arg) final;
- virtual unique_fd Destroy(fdevent* fde) final;
-
- virtual void Set(fdevent* fde, unsigned events) final;
- virtual void Add(fdevent* fde, unsigned events) final;
- virtual void Del(fdevent* fde, unsigned events) final;
- virtual void SetTimeout(fdevent* fde, std::optional<std::chrono::milliseconds> timeout) final;
-
- virtual void Loop() final;
-
- virtual void CheckMainThread() final;
-
- virtual void Run(std::function<void()> fn) final;
-
- virtual void TerminateLoop() final;
- virtual size_t InstalledCount() final;
- virtual void Reset() final;
-
- // All operations to fdevent should happen only in the main thread.
- // That's why we don't need a lock for fdevent.
- std::unordered_map<int, PollNode> poll_node_map_;
- std::list<fdevent*> pending_list_;
- bool main_thread_valid_ = false;
- uint64_t main_thread_id_ = 0;
- uint64_t fdevent_id_ = 0;
-
- bool run_needs_flush_ = false;
- unique_fd run_queue_notify_fd_;
- std::mutex run_queue_mutex_;
- std::deque<std::function<void()>> run_queue_ GUARDED_BY(run_queue_mutex_);
-
- std::atomic<bool> terminate_loop_ = false;
-};
-
static fdevent_context* g_ambient_fdevent_context = new fdevent_context_poll();
static fdevent_context* fdevent_get_ambient() {
return g_ambient_fdevent_context;
}
-void fdevent_context_poll::CheckMainThread() {
- if (main_thread_valid_) {
- CHECK_EQ(main_thread_id_, android::base::GetThreadId());
- }
-}
-
-fdevent* fdevent_context_poll::Create(unique_fd fd, std::variant<fd_func, fd_func2> func,
- void* arg) {
- CheckMainThread();
- CHECK_GE(fd.get(), 0);
-
- fdevent* fde = new fdevent();
- fde->id = fdevent_id_++;
- fde->state = FDE_ACTIVE;
- fde->fd = std::move(fd);
- fde->func = func;
- fde->arg = arg;
- if (!set_file_block_mode(fde->fd, false)) {
- // Here is not proper to handle the error. If it fails here, some error is
- // likely to be detected by poll(), then we can let the callback function
- // to handle it.
- LOG(ERROR) << "failed to set non-blocking mode for fd " << fde->fd.get();
- }
- auto pair = poll_node_map_.emplace(fde->fd.get(), PollNode(fde));
- CHECK(pair.second) << "install existing fd " << fde->fd.get();
-
- fde->state |= FDE_CREATED;
- return fde;
-}
-
-unique_fd fdevent_context_poll::Destroy(fdevent* fde) {
- CheckMainThread();
- if (!fde) {
- return {};
- }
-
- if (!(fde->state & FDE_CREATED)) {
- LOG(FATAL) << "destroying fde not created by fdevent_create(): " << dump_fde(fde);
- }
-
- unique_fd result = std::move(fde->fd);
- if (fde->state & FDE_ACTIVE) {
- poll_node_map_.erase(result.get());
-
- if (fde->state & FDE_PENDING) {
- pending_list_.remove(fde);
- }
- fde->state = 0;
- fde->events = 0;
- }
-
- delete fde;
- return result;
-}
-
-void fdevent_context_poll::Set(fdevent* fde, unsigned events) {
- CheckMainThread();
- events &= FDE_EVENTMASK;
- if ((fde->state & FDE_EVENTMASK) == events) {
- return;
- }
- CHECK(fde->state & FDE_ACTIVE);
-
- auto it = poll_node_map_.find(fde->fd.get());
- CHECK(it != poll_node_map_.end());
- PollNode& node = it->second;
- if (events & FDE_READ) {
- node.pollfd.events |= POLLIN;
- } else {
- node.pollfd.events &= ~POLLIN;
- }
-
- if (events & FDE_WRITE) {
- node.pollfd.events |= POLLOUT;
- } else {
- node.pollfd.events &= ~POLLOUT;
- }
- fde->state = (fde->state & FDE_STATEMASK) | events;
-
- D("fdevent_set: %s, events = %u", dump_fde(fde).c_str(), events);
-
- if (fde->state & FDE_PENDING) {
- // If we are pending, make sure we don't signal an event that is no longer wanted.
- fde->events &= events;
- if (fde->events == 0) {
- pending_list_.remove(fde);
- fde->state &= ~FDE_PENDING;
- }
- }
-}
-
-void fdevent_context_poll::Add(fdevent* fde, unsigned events) {
- Set(fde, (fde->state & FDE_EVENTMASK) | events);
-}
-
-void fdevent_context_poll::Del(fdevent* fde, unsigned events) {
- CHECK(!(events & FDE_TIMEOUT));
- Set(fde, (fde->state & FDE_EVENTMASK) & ~events);
-}
-
-void fdevent_context_poll::SetTimeout(fdevent* fde,
- std::optional<std::chrono::milliseconds> timeout) {
- CheckMainThread();
- fde->timeout = timeout;
- fde->last_active = std::chrono::steady_clock::now();
-}
-
-static std::string dump_pollfds(const std::vector<adb_pollfd>& pollfds) {
- std::string result;
- for (const auto& pollfd : pollfds) {
- std::string op;
- if (pollfd.events & POLLIN) {
- op += "R";
- }
- if (pollfd.events & POLLOUT) {
- op += "W";
- }
- android::base::StringAppendF(&result, " %d(%s)", pollfd.fd, op.c_str());
- }
- return result;
-}
-
-static std::optional<std::chrono::milliseconds> calculate_timeout(fdevent_context_poll* ctx) {
- std::optional<std::chrono::milliseconds> result = std::nullopt;
- auto now = std::chrono::steady_clock::now();
- ctx->CheckMainThread();
-
- for (const auto& [fd, pollnode] : ctx->poll_node_map_) {
- UNUSED(fd);
- auto timeout_opt = pollnode.fde->timeout;
- if (timeout_opt) {
- auto deadline = pollnode.fde->last_active + *timeout_opt;
- auto time_left = std::chrono::duration_cast<std::chrono::milliseconds>(deadline - now);
- if (time_left < std::chrono::milliseconds::zero()) {
- time_left = std::chrono::milliseconds::zero();
- }
-
- if (!result) {
- result = time_left;
- } else {
- result = std::min(*result, time_left);
- }
- }
- }
-
- return result;
-}
-
-static void fdevent_process(fdevent_context_poll* ctx) {
- std::vector<adb_pollfd> pollfds;
- for (const auto& pair : ctx->poll_node_map_) {
- pollfds.push_back(pair.second.pollfd);
- }
- CHECK_GT(pollfds.size(), 0u);
- D("poll(), pollfds = %s", dump_pollfds(pollfds).c_str());
-
- auto timeout = calculate_timeout(ctx);
- int timeout_ms;
- if (!timeout) {
- timeout_ms = -1;
- } else {
- timeout_ms = timeout->count();
- }
-
- int ret = adb_poll(&pollfds[0], pollfds.size(), timeout_ms);
- if (ret == -1) {
- PLOG(ERROR) << "poll(), ret = " << ret;
- return;
- }
-
- auto post_poll = std::chrono::steady_clock::now();
-
- for (const auto& pollfd : pollfds) {
- if (pollfd.revents != 0) {
- D("for fd %d, revents = %x", pollfd.fd, pollfd.revents);
- }
- unsigned events = 0;
- if (pollfd.revents & POLLIN) {
- events |= FDE_READ;
- }
- if (pollfd.revents & POLLOUT) {
- events |= FDE_WRITE;
- }
- if (pollfd.revents & (POLLERR | POLLHUP | POLLNVAL)) {
- // We fake a read, as the rest of the code assumes that errors will
- // be detected at that point.
- events |= FDE_READ | FDE_ERROR;
- }
-#if defined(__linux__)
- if (pollfd.revents & POLLRDHUP) {
- events |= FDE_READ | FDE_ERROR;
- }
-#endif
- auto it = ctx->poll_node_map_.find(pollfd.fd);
- CHECK(it != ctx->poll_node_map_.end());
- fdevent* fde = it->second.fde;
-
- if (events == 0) {
- // Check for timeout.
- if (fde->timeout) {
- auto deadline = fde->last_active + *fde->timeout;
- if (deadline < post_poll) {
- events |= FDE_TIMEOUT;
- }
- }
- }
-
- if (events != 0) {
- CHECK_EQ(fde->fd.get(), pollfd.fd);
- fde->events |= events;
- fde->last_active = post_poll;
- D("%s got events %x", dump_fde(fde).c_str(), events);
- fde->state |= FDE_PENDING;
- ctx->pending_list_.push_back(fde);
- }
- }
-}
-
-template <class T>
-struct always_false : std::false_type {};
-
-static void fdevent_call_fdfunc(fdevent* fde) {
- unsigned events = fde->events;
- fde->events = 0;
- CHECK(fde->state & FDE_PENDING);
- fde->state &= (~FDE_PENDING);
- D("fdevent_call_fdfunc %s", dump_fde(fde).c_str());
- std::visit(
- [&](auto&& f) {
- using F = std::decay_t<decltype(f)>;
- if constexpr (std::is_same_v<fd_func, F>) {
- f(fde->fd.get(), events, fde->arg);
- } else if constexpr (std::is_same_v<fd_func2, F>) {
- f(fde, events, fde->arg);
- } else {
- static_assert(always_false<F>::value, "non-exhaustive visitor");
- }
- },
- fde->func);
-}
-
-static void fdevent_run_flush(fdevent_context_poll* ctx) EXCLUDES(ctx->run_queue_mutex_) {
- // We need to be careful around reentrancy here, since a function we call can queue up another
- // function.
- while (true) {
- std::function<void()> fn;
- {
- std::lock_guard<std::mutex> lock(ctx->run_queue_mutex_);
- if (ctx->run_queue_.empty()) {
- break;
- }
- fn = ctx->run_queue_.front();
- ctx->run_queue_.pop_front();
- }
- fn();
- }
-}
-
-static void fdevent_run_func(int fd, unsigned ev, void* data) {
- CHECK_GE(fd, 0);
- CHECK(ev & FDE_READ);
-
- bool* run_needs_flush = static_cast<bool*>(data);
- char buf[1024];
-
- // Empty the fd.
- if (adb_read(fd, buf, sizeof(buf)) == -1) {
- PLOG(FATAL) << "failed to empty run queue notify fd";
- }
-
- // Mark that we need to flush, and then run it at the end of fdevent_loop.
- *run_needs_flush = true;
-}
-
-static void fdevent_run_setup(fdevent_context_poll* ctx) {
- {
- std::lock_guard<std::mutex> lock(ctx->run_queue_mutex_);
- CHECK(ctx->run_queue_notify_fd_.get() == -1);
- int s[2];
- if (adb_socketpair(s) != 0) {
- PLOG(FATAL) << "failed to create run queue notify socketpair";
- }
-
- if (!set_file_block_mode(s[0], false) || !set_file_block_mode(s[1], false)) {
- PLOG(FATAL) << "failed to make run queue notify socket nonblocking";
- }
-
- ctx->run_queue_notify_fd_.reset(s[0]);
- fdevent* fde = ctx->Create(unique_fd(s[1]), fdevent_run_func, &ctx->run_needs_flush_);
- CHECK(fde != nullptr);
- ctx->Add(fde, FDE_READ);
- }
-
- fdevent_run_flush(ctx);
-}
-
-void fdevent_context_poll::Run(std::function<void()> fn) {
- std::lock_guard<std::mutex> lock(run_queue_mutex_);
- run_queue_.push_back(std::move(fn));
-
- // run_queue_notify_fd could still be -1 if we're called before fdevent has finished setting up.
- // In that case, rely on the setup code to flush the queue without a notification being needed.
- if (run_queue_notify_fd_ != -1) {
- int rc = adb_write(run_queue_notify_fd_.get(), "", 1);
-
- // It's possible that we get EAGAIN here, if lots of notifications came in while handling.
- if (rc == 0) {
- PLOG(FATAL) << "run queue notify fd was closed?";
- } else if (rc == -1 && errno != EAGAIN) {
- PLOG(FATAL) << "failed to write to run queue notify fd";
- }
- }
-}
-
-static void fdevent_check_spin(fdevent_context_poll* ctx, uint64_t cycle) {
- // Check to see if we're spinning because we forgot about an fdevent
- // by keeping track of how long fdevents have been continuously pending.
- struct SpinCheck {
- fdevent* fde;
- android::base::boot_clock::time_point timestamp;
- uint64_t cycle;
- };
-
- // TODO: Move this into the base fdevent_context.
- static auto& g_continuously_pending = *new std::unordered_map<uint64_t, SpinCheck>();
- static auto last_cycle = android::base::boot_clock::now();
-
- auto now = android::base::boot_clock::now();
- if (now - last_cycle > 10ms) {
- // We're not spinning.
- g_continuously_pending.clear();
- last_cycle = now;
- return;
- }
- last_cycle = now;
-
- for (auto* fde : ctx->pending_list_) {
- auto it = g_continuously_pending.find(fde->id);
- if (it == g_continuously_pending.end()) {
- g_continuously_pending[fde->id] =
- SpinCheck{.fde = fde, .timestamp = now, .cycle = cycle};
- } else {
- it->second.cycle = cycle;
- }
- }
-
- for (auto it = g_continuously_pending.begin(); it != g_continuously_pending.end();) {
- if (it->second.cycle != cycle) {
- it = g_continuously_pending.erase(it);
- } else {
- // Use an absurdly long window, since all we really care about is
- // getting a bugreport eventually.
- if (now - it->second.timestamp > 300s) {
- LOG(FATAL_WITHOUT_ABORT)
- << "detected spin in fdevent: " << dump_fde(it->second.fde);
-#if defined(__linux__)
- int fd = it->second.fde->fd.get();
- std::string fd_path = android::base::StringPrintf("/proc/self/fd/%d", fd);
- std::string path;
- if (!android::base::Readlink(fd_path, &path)) {
- PLOG(FATAL_WITHOUT_ABORT) << "readlink of fd " << fd << " failed";
- }
- LOG(FATAL_WITHOUT_ABORT) << "fd " << fd << " = " << path;
-#endif
- abort();
- }
- ++it;
- }
- }
-}
-
-void fdevent_context_poll::Loop() {
- this->main_thread_id_ = android::base::GetThreadId();
- this->main_thread_valid_ = true;
- fdevent_run_setup(this);
-
- uint64_t cycle = 0;
- while (true) {
- if (terminate_loop_) {
- return;
- }
-
- D("--- --- waiting for events");
-
- fdevent_process(this);
-
- fdevent_check_spin(this, cycle++);
-
- while (!pending_list_.empty()) {
- fdevent* fde = pending_list_.front();
- pending_list_.pop_front();
- fdevent_call_fdfunc(fde);
- }
-
- if (run_needs_flush_) {
- fdevent_run_flush(this);
- run_needs_flush_ = false;
- }
- }
-}
-
-void fdevent_context_poll::TerminateLoop() {
- terminate_loop_ = true;
-}
-
-size_t fdevent_context_poll::InstalledCount() {
- return poll_node_map_.size();
-}
-
-void fdevent_context_poll::Reset() {
- poll_node_map_.clear();
- pending_list_.clear();
-
- std::lock_guard<std::mutex> lock(run_queue_mutex_);
- run_queue_notify_fd_.reset();
- run_queue_.clear();
-
- main_thread_valid_ = false;
- terminate_loop_ = false;
-}
-
fdevent* fdevent_create(int fd, fd_func func, void* arg) {
unique_fd ufd(fd);
return fdevent_get_ambient()->Create(std::move(ufd), func, arg);
diff --git a/adb/fdevent/fdevent.h b/adb/fdevent/fdevent.h
index a953cc1..7bc50f4 100644
--- a/adb/fdevent/fdevent.h
+++ b/adb/fdevent/fdevent.h
@@ -33,10 +33,19 @@
#define FDE_ERROR 0x0004
#define FDE_TIMEOUT 0x0008
+// Internal states.
+#define FDE_EVENTMASK 0x00ff
+#define FDE_STATEMASK 0xff00
+
+#define FDE_ACTIVE 0x0100
+#define FDE_PENDING 0x0200
+#define FDE_CREATED 0x0400
+
typedef void (*fd_func)(int fd, unsigned events, void *userdata);
typedef void (*fd_func2)(struct fdevent* fde, unsigned events, void* userdata);
struct fdevent;
+std::string dump_fde(const fdevent* fde);
struct fdevent_context {
virtual ~fdevent_context() = default;
diff --git a/adb/fdevent/fdevent_poll.cpp b/adb/fdevent/fdevent_poll.cpp
new file mode 100644
index 0000000..63ef3f1
--- /dev/null
+++ b/adb/fdevent/fdevent_poll.cpp
@@ -0,0 +1,472 @@
+/*
+ * Copyright (C) 2019 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 TRACE_TAG FDEVENT
+
+#include "sysdeps.h"
+#include "fdevent_poll.h"
+
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <atomic>
+#include <deque>
+#include <functional>
+#include <list>
+#include <mutex>
+#include <optional>
+#include <unordered_map>
+#include <utility>
+#include <variant>
+#include <vector>
+
+#include <android-base/chrono_utils.h>
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <android-base/threads.h>
+
+#include "adb_io.h"
+#include "adb_trace.h"
+#include "adb_unique_fd.h"
+#include "adb_utils.h"
+#include "fdevent.h"
+#include "sysdeps/chrono.h"
+
+void fdevent_context_poll::CheckMainThread() {
+ if (main_thread_valid_) {
+ CHECK_EQ(main_thread_id_, android::base::GetThreadId());
+ }
+}
+
+fdevent* fdevent_context_poll::Create(unique_fd fd, std::variant<fd_func, fd_func2> func,
+ void* arg) {
+ CheckMainThread();
+ CHECK_GE(fd.get(), 0);
+
+ fdevent* fde = new fdevent();
+ fde->id = fdevent_id_++;
+ fde->state = FDE_ACTIVE;
+ fde->fd = std::move(fd);
+ fde->func = func;
+ fde->arg = arg;
+ if (!set_file_block_mode(fde->fd, false)) {
+ // Here is not proper to handle the error. If it fails here, some error is
+ // likely to be detected by poll(), then we can let the callback function
+ // to handle it.
+ LOG(ERROR) << "failed to set non-blocking mode for fd " << fde->fd.get();
+ }
+ auto pair = poll_node_map_.emplace(fde->fd.get(), PollNode(fde));
+ CHECK(pair.second) << "install existing fd " << fde->fd.get();
+
+ fde->state |= FDE_CREATED;
+ return fde;
+}
+
+unique_fd fdevent_context_poll::Destroy(fdevent* fde) {
+ CheckMainThread();
+ if (!fde) {
+ return {};
+ }
+
+ if (!(fde->state & FDE_CREATED)) {
+ LOG(FATAL) << "destroying fde not created by fdevent_create(): " << dump_fde(fde);
+ }
+
+ unique_fd result = std::move(fde->fd);
+ if (fde->state & FDE_ACTIVE) {
+ poll_node_map_.erase(result.get());
+
+ if (fde->state & FDE_PENDING) {
+ pending_list_.remove(fde);
+ }
+ fde->state = 0;
+ fde->events = 0;
+ }
+
+ delete fde;
+ return result;
+}
+
+void fdevent_context_poll::Set(fdevent* fde, unsigned events) {
+ CheckMainThread();
+ events &= FDE_EVENTMASK;
+ if ((fde->state & FDE_EVENTMASK) == events) {
+ return;
+ }
+ CHECK(fde->state & FDE_ACTIVE);
+
+ auto it = poll_node_map_.find(fde->fd.get());
+ CHECK(it != poll_node_map_.end());
+ PollNode& node = it->second;
+ if (events & FDE_READ) {
+ node.pollfd.events |= POLLIN;
+ } else {
+ node.pollfd.events &= ~POLLIN;
+ }
+
+ if (events & FDE_WRITE) {
+ node.pollfd.events |= POLLOUT;
+ } else {
+ node.pollfd.events &= ~POLLOUT;
+ }
+ fde->state = (fde->state & FDE_STATEMASK) | events;
+
+ D("fdevent_set: %s, events = %u", dump_fde(fde).c_str(), events);
+
+ if (fde->state & FDE_PENDING) {
+ // If we are pending, make sure we don't signal an event that is no longer wanted.
+ fde->events &= events;
+ if (fde->events == 0) {
+ pending_list_.remove(fde);
+ fde->state &= ~FDE_PENDING;
+ }
+ }
+}
+
+void fdevent_context_poll::Add(fdevent* fde, unsigned events) {
+ Set(fde, (fde->state & FDE_EVENTMASK) | events);
+}
+
+void fdevent_context_poll::Del(fdevent* fde, unsigned events) {
+ CHECK(!(events & FDE_TIMEOUT));
+ Set(fde, (fde->state & FDE_EVENTMASK) & ~events);
+}
+
+void fdevent_context_poll::SetTimeout(fdevent* fde,
+ std::optional<std::chrono::milliseconds> timeout) {
+ CheckMainThread();
+ fde->timeout = timeout;
+ fde->last_active = std::chrono::steady_clock::now();
+}
+
+static std::string dump_pollfds(const std::vector<adb_pollfd>& pollfds) {
+ std::string result;
+ for (const auto& pollfd : pollfds) {
+ std::string op;
+ if (pollfd.events & POLLIN) {
+ op += "R";
+ }
+ if (pollfd.events & POLLOUT) {
+ op += "W";
+ }
+ android::base::StringAppendF(&result, " %d(%s)", pollfd.fd, op.c_str());
+ }
+ return result;
+}
+
+static std::optional<std::chrono::milliseconds> calculate_timeout(fdevent_context_poll* ctx) {
+ std::optional<std::chrono::milliseconds> result = std::nullopt;
+ auto now = std::chrono::steady_clock::now();
+ ctx->CheckMainThread();
+
+ for (const auto& [fd, pollnode] : ctx->poll_node_map_) {
+ UNUSED(fd);
+ auto timeout_opt = pollnode.fde->timeout;
+ if (timeout_opt) {
+ auto deadline = pollnode.fde->last_active + *timeout_opt;
+ auto time_left = std::chrono::duration_cast<std::chrono::milliseconds>(deadline - now);
+ if (time_left < std::chrono::milliseconds::zero()) {
+ time_left = std::chrono::milliseconds::zero();
+ }
+
+ if (!result) {
+ result = time_left;
+ } else {
+ result = std::min(*result, time_left);
+ }
+ }
+ }
+
+ return result;
+}
+
+static void fdevent_process(fdevent_context_poll* ctx) {
+ std::vector<adb_pollfd> pollfds;
+ for (const auto& pair : ctx->poll_node_map_) {
+ pollfds.push_back(pair.second.pollfd);
+ }
+ CHECK_GT(pollfds.size(), 0u);
+ D("poll(), pollfds = %s", dump_pollfds(pollfds).c_str());
+
+ auto timeout = calculate_timeout(ctx);
+ int timeout_ms;
+ if (!timeout) {
+ timeout_ms = -1;
+ } else {
+ timeout_ms = timeout->count();
+ }
+
+ int ret = adb_poll(&pollfds[0], pollfds.size(), timeout_ms);
+ if (ret == -1) {
+ PLOG(ERROR) << "poll(), ret = " << ret;
+ return;
+ }
+
+ auto post_poll = std::chrono::steady_clock::now();
+
+ for (const auto& pollfd : pollfds) {
+ if (pollfd.revents != 0) {
+ D("for fd %d, revents = %x", pollfd.fd, pollfd.revents);
+ }
+ unsigned events = 0;
+ if (pollfd.revents & POLLIN) {
+ events |= FDE_READ;
+ }
+ if (pollfd.revents & POLLOUT) {
+ events |= FDE_WRITE;
+ }
+ if (pollfd.revents & (POLLERR | POLLHUP | POLLNVAL)) {
+ // We fake a read, as the rest of the code assumes that errors will
+ // be detected at that point.
+ events |= FDE_READ | FDE_ERROR;
+ }
+#if defined(__linux__)
+ if (pollfd.revents & POLLRDHUP) {
+ events |= FDE_READ | FDE_ERROR;
+ }
+#endif
+ auto it = ctx->poll_node_map_.find(pollfd.fd);
+ CHECK(it != ctx->poll_node_map_.end());
+ fdevent* fde = it->second.fde;
+
+ if (events == 0) {
+ // Check for timeout.
+ if (fde->timeout) {
+ auto deadline = fde->last_active + *fde->timeout;
+ if (deadline < post_poll) {
+ events |= FDE_TIMEOUT;
+ }
+ }
+ }
+
+ if (events != 0) {
+ CHECK_EQ(fde->fd.get(), pollfd.fd);
+ fde->events |= events;
+ fde->last_active = post_poll;
+ D("%s got events %x", dump_fde(fde).c_str(), events);
+ fde->state |= FDE_PENDING;
+ ctx->pending_list_.push_back(fde);
+ }
+ }
+}
+
+template <class T>
+struct always_false : std::false_type {};
+
+static void fdevent_call_fdfunc(fdevent* fde) {
+ unsigned events = fde->events;
+ fde->events = 0;
+ CHECK(fde->state & FDE_PENDING);
+ fde->state &= (~FDE_PENDING);
+ D("fdevent_call_fdfunc %s", dump_fde(fde).c_str());
+ std::visit(
+ [&](auto&& f) {
+ using F = std::decay_t<decltype(f)>;
+ if constexpr (std::is_same_v<fd_func, F>) {
+ f(fde->fd.get(), events, fde->arg);
+ } else if constexpr (std::is_same_v<fd_func2, F>) {
+ f(fde, events, fde->arg);
+ } else {
+ static_assert(always_false<F>::value, "non-exhaustive visitor");
+ }
+ },
+ fde->func);
+}
+
+static void fdevent_run_flush(fdevent_context_poll* ctx) EXCLUDES(ctx->run_queue_mutex_) {
+ // We need to be careful around reentrancy here, since a function we call can queue up another
+ // function.
+ while (true) {
+ std::function<void()> fn;
+ {
+ std::lock_guard<std::mutex> lock(ctx->run_queue_mutex_);
+ if (ctx->run_queue_.empty()) {
+ break;
+ }
+ fn = ctx->run_queue_.front();
+ ctx->run_queue_.pop_front();
+ }
+ fn();
+ }
+}
+
+static void fdevent_run_func(int fd, unsigned ev, void* data) {
+ CHECK_GE(fd, 0);
+ CHECK(ev & FDE_READ);
+
+ bool* run_needs_flush = static_cast<bool*>(data);
+ char buf[1024];
+
+ // Empty the fd.
+ if (adb_read(fd, buf, sizeof(buf)) == -1) {
+ PLOG(FATAL) << "failed to empty run queue notify fd";
+ }
+
+ // Mark that we need to flush, and then run it at the end of fdevent_loop.
+ *run_needs_flush = true;
+}
+
+static void fdevent_run_setup(fdevent_context_poll* ctx) {
+ {
+ std::lock_guard<std::mutex> lock(ctx->run_queue_mutex_);
+ CHECK(ctx->run_queue_notify_fd_.get() == -1);
+ int s[2];
+ if (adb_socketpair(s) != 0) {
+ PLOG(FATAL) << "failed to create run queue notify socketpair";
+ }
+
+ if (!set_file_block_mode(s[0], false) || !set_file_block_mode(s[1], false)) {
+ PLOG(FATAL) << "failed to make run queue notify socket nonblocking";
+ }
+
+ ctx->run_queue_notify_fd_.reset(s[0]);
+ fdevent* fde = ctx->Create(unique_fd(s[1]), fdevent_run_func, &ctx->run_needs_flush_);
+ CHECK(fde != nullptr);
+ ctx->Add(fde, FDE_READ);
+ }
+
+ fdevent_run_flush(ctx);
+}
+
+void fdevent_context_poll::Run(std::function<void()> fn) {
+ std::lock_guard<std::mutex> lock(run_queue_mutex_);
+ run_queue_.push_back(std::move(fn));
+
+ // run_queue_notify_fd could still be -1 if we're called before fdevent has finished setting up.
+ // In that case, rely on the setup code to flush the queue without a notification being needed.
+ if (run_queue_notify_fd_ != -1) {
+ int rc = adb_write(run_queue_notify_fd_.get(), "", 1);
+
+ // It's possible that we get EAGAIN here, if lots of notifications came in while handling.
+ if (rc == 0) {
+ PLOG(FATAL) << "run queue notify fd was closed?";
+ } else if (rc == -1 && errno != EAGAIN) {
+ PLOG(FATAL) << "failed to write to run queue notify fd";
+ }
+ }
+}
+
+static void fdevent_check_spin(fdevent_context_poll* ctx, uint64_t cycle) {
+ // Check to see if we're spinning because we forgot about an fdevent
+ // by keeping track of how long fdevents have been continuously pending.
+ struct SpinCheck {
+ fdevent* fde;
+ android::base::boot_clock::time_point timestamp;
+ uint64_t cycle;
+ };
+
+ // TODO: Move this into the base fdevent_context.
+ static auto& g_continuously_pending = *new std::unordered_map<uint64_t, SpinCheck>();
+ static auto last_cycle = android::base::boot_clock::now();
+
+ auto now = android::base::boot_clock::now();
+ if (now - last_cycle > 10ms) {
+ // We're not spinning.
+ g_continuously_pending.clear();
+ last_cycle = now;
+ return;
+ }
+ last_cycle = now;
+
+ for (auto* fde : ctx->pending_list_) {
+ auto it = g_continuously_pending.find(fde->id);
+ if (it == g_continuously_pending.end()) {
+ g_continuously_pending[fde->id] =
+ SpinCheck{.fde = fde, .timestamp = now, .cycle = cycle};
+ } else {
+ it->second.cycle = cycle;
+ }
+ }
+
+ for (auto it = g_continuously_pending.begin(); it != g_continuously_pending.end();) {
+ if (it->second.cycle != cycle) {
+ it = g_continuously_pending.erase(it);
+ } else {
+ // Use an absurdly long window, since all we really care about is
+ // getting a bugreport eventually.
+ if (now - it->second.timestamp > 300s) {
+ LOG(FATAL_WITHOUT_ABORT)
+ << "detected spin in fdevent: " << dump_fde(it->second.fde);
+#if defined(__linux__)
+ int fd = it->second.fde->fd.get();
+ std::string fd_path = android::base::StringPrintf("/proc/self/fd/%d", fd);
+ std::string path;
+ if (!android::base::Readlink(fd_path, &path)) {
+ PLOG(FATAL_WITHOUT_ABORT) << "readlink of fd " << fd << " failed";
+ }
+ LOG(FATAL_WITHOUT_ABORT) << "fd " << fd << " = " << path;
+#endif
+ abort();
+ }
+ ++it;
+ }
+ }
+}
+
+void fdevent_context_poll::Loop() {
+ this->main_thread_id_ = android::base::GetThreadId();
+ this->main_thread_valid_ = true;
+ fdevent_run_setup(this);
+
+ uint64_t cycle = 0;
+ while (true) {
+ if (terminate_loop_) {
+ return;
+ }
+
+ D("--- --- waiting for events");
+
+ fdevent_process(this);
+
+ fdevent_check_spin(this, cycle++);
+
+ while (!pending_list_.empty()) {
+ fdevent* fde = pending_list_.front();
+ pending_list_.pop_front();
+ fdevent_call_fdfunc(fde);
+ }
+
+ if (run_needs_flush_) {
+ fdevent_run_flush(this);
+ run_needs_flush_ = false;
+ }
+ }
+}
+
+void fdevent_context_poll::TerminateLoop() {
+ terminate_loop_ = true;
+}
+
+size_t fdevent_context_poll::InstalledCount() {
+ return poll_node_map_.size();
+}
+
+void fdevent_context_poll::Reset() {
+ poll_node_map_.clear();
+ pending_list_.clear();
+
+ std::lock_guard<std::mutex> lock(run_queue_mutex_);
+ run_queue_notify_fd_.reset();
+ run_queue_.clear();
+
+ main_thread_valid_ = false;
+ terminate_loop_ = false;
+}
diff --git a/adb/fdevent/fdevent_poll.h b/adb/fdevent/fdevent_poll.h
new file mode 100644
index 0000000..aa82ee5
--- /dev/null
+++ b/adb/fdevent/fdevent_poll.h
@@ -0,0 +1,81 @@
+#pragma once
+
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#include "sysdeps.h"
+
+#include <deque>
+#include <list>
+#include <mutex>
+#include <unordered_map>
+
+#include <android-base/thread_annotations.h>
+
+#include "fdevent.h"
+
+struct PollNode {
+ fdevent* fde;
+ adb_pollfd pollfd;
+
+ explicit PollNode(fdevent* fde) : fde(fde) {
+ memset(&pollfd, 0, sizeof(pollfd));
+ pollfd.fd = fde->fd.get();
+
+#if defined(__linux__)
+ // Always enable POLLRDHUP, so the host server can take action when some clients disconnect.
+ // Then we can avoid leaving many sockets in CLOSE_WAIT state. See http://b/23314034.
+ pollfd.events = POLLRDHUP;
+#endif
+ }
+};
+
+struct fdevent_context_poll : public fdevent_context {
+ virtual ~fdevent_context_poll() = default;
+
+ virtual fdevent* Create(unique_fd fd, std::variant<fd_func, fd_func2> func, void* arg) final;
+ virtual unique_fd Destroy(fdevent* fde) final;
+
+ virtual void Set(fdevent* fde, unsigned events) final;
+ virtual void Add(fdevent* fde, unsigned events) final;
+ virtual void Del(fdevent* fde, unsigned events) final;
+ virtual void SetTimeout(fdevent* fde, std::optional<std::chrono::milliseconds> timeout) final;
+
+ virtual void Loop() final;
+
+ virtual void CheckMainThread() final;
+
+ virtual void Run(std::function<void()> fn) final;
+
+ virtual void TerminateLoop() final;
+ virtual size_t InstalledCount() final;
+ virtual void Reset() final;
+
+ // All operations to fdevent should happen only in the main thread.
+ // That's why we don't need a lock for fdevent.
+ std::unordered_map<int, PollNode> poll_node_map_;
+ std::list<fdevent*> pending_list_;
+ bool main_thread_valid_ = false;
+ uint64_t main_thread_id_ = 0;
+ uint64_t fdevent_id_ = 0;
+
+ bool run_needs_flush_ = false;
+ unique_fd run_queue_notify_fd_;
+ std::mutex run_queue_mutex_;
+ std::deque<std::function<void()>> run_queue_ GUARDED_BY(run_queue_mutex_);
+
+ std::atomic<bool> terminate_loop_ = false;
+};