libbinder: FdTrigger encapsulate poll
So we can use this in other places.
Bug: 185167543
Test: binderRpcTest
Change-Id: Ie8012b1c8dcea035bc8d0f14af2bd2ddbb197d89
diff --git a/libs/binder/RpcServer.cpp b/libs/binder/RpcServer.cpp
index df7c844..249ce6c 100644
--- a/libs/binder/RpcServer.cpp
+++ b/libs/binder/RpcServer.cpp
@@ -16,14 +16,12 @@
#define LOG_TAG "RpcServer"
-#include <poll.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <thread>
#include <vector>
-#include <android-base/macros.h>
#include <android-base/scopeguard.h>
#include <binder/Parcel.h>
#include <binder/RpcServer.h>
@@ -140,22 +138,7 @@
LOG_ALWAYS_FATAL_IF(mShutdownTrigger == nullptr, "Cannot create join signaler");
}
- while (true) {
- pollfd pfd[]{{.fd = mServer.get(), .events = POLLIN, .revents = 0},
- {.fd = mShutdownTrigger->readFd().get(), .events = POLLHUP, .revents = 0}};
- int ret = TEMP_FAILURE_RETRY(poll(pfd, arraysize(pfd), -1));
- if (ret < 0) {
- ALOGE("Could not poll socket: %s", strerror(errno));
- continue;
- }
- if (ret == 0) {
- continue;
- }
- if (pfd[1].revents & POLLHUP) {
- LOG_RPC_DETAIL("join() exiting because shutdown requested.");
- break;
- }
-
+ while (mShutdownTrigger->triggerablePollRead(mServer)) {
(void)acceptOneNoCheck();
}
diff --git a/libs/binder/RpcSession.cpp b/libs/binder/RpcSession.cpp
index 4efa6bb..ea82f36 100644
--- a/libs/binder/RpcSession.cpp
+++ b/libs/binder/RpcSession.cpp
@@ -19,10 +19,12 @@
#include <binder/RpcSession.h>
#include <inttypes.h>
+#include <poll.h>
#include <unistd.h>
#include <string_view>
+#include <android-base/macros.h>
#include <binder/Parcel.h>
#include <binder/RpcServer.h>
#include <binder/Stability.h>
@@ -123,6 +125,25 @@
mWrite.reset();
}
+bool RpcSession::FdTrigger::triggerablePollRead(base::borrowed_fd fd) {
+ while (true) {
+ pollfd pfd[]{{.fd = fd.get(), .events = POLLIN, .revents = 0},
+ {.fd = mRead.get(), .events = POLLHUP, .revents = 0}};
+ int ret = TEMP_FAILURE_RETRY(poll(pfd, arraysize(pfd), -1));
+ if (ret < 0) {
+ ALOGE("Could not poll: %s", strerror(errno));
+ continue;
+ }
+ if (ret == 0) {
+ continue;
+ }
+ if (pfd[1].revents & POLLHUP) {
+ return false;
+ }
+ return true;
+ }
+}
+
status_t RpcSession::readId() {
{
std::lock_guard<std::mutex> _l(mMutex);
diff --git a/libs/binder/include/binder/RpcSession.h b/libs/binder/include/binder/RpcSession.h
index 6a60e7e..bcef8dc 100644
--- a/libs/binder/include/binder/RpcSession.h
+++ b/libs/binder/include/binder/RpcSession.h
@@ -119,11 +119,21 @@
* poll() on this fd for POLLHUP to get notification when trigger is called
*/
base::borrowed_fd readFd() const { return mRead; }
+
/**
* Close the write end of the pipe so that the read end receives POLLHUP.
*/
void trigger();
+ /**
+ * Poll for a read event.
+ *
+ * Return:
+ * true - time to read!
+ * false - trigger happened
+ */
+ bool triggerablePollRead(base::borrowed_fd fd);
+
private:
base::unique_fd mWrite;
base::unique_fd mRead;