binder: Refactor: move FdTrigger to its own file / class.

Also move interruptable*Fully functions to RpcTransport so that we no
longer need pending() and pollSocket().

This also allows us to hide send() / recv(); callers should use
interruptableWriteFully / interruptableReadFully instead, because
those repsect the shutdown trigger.
- Fix one place to use interruptableWriteFully() instead of send() when
  sending header.

interruptable*Fully are marked as virtual functions because TLS will
need to poll with events dynamically adjusted. See follow-up CLs for
TLS implementation.

Test: TH
Bug: 190868302
Change-Id: I131eed3a637b3a30280b320966e466bbfac0fc45

1 files changed, 6 insertions, 5 deletions

diff --git a/libs/binder/RpcServer.cpp b/libs/binder/RpcServer.cpp
index 4fa99c0e45..66483edffb 100644
--- a/libs/binder/RpcServer.cpp
+++ b/libs/binder/RpcServer.cpp
@@ -29,6 +29,7 @@
 #include <binder/RpcTransportRaw.h>
 #include <log/log.h>
 
+#include "FdTrigger.h"
 #include "RpcSocketAddress.h"
 #include "RpcState.h"
 #include "RpcWireFormat.h"
@@ -156,7 +157,7 @@ void RpcServer::join() {
         LOG_ALWAYS_FATAL_IF(!mServer.ok(), "RpcServer must be setup to join.");
         LOG_ALWAYS_FATAL_IF(mShutdownTrigger != nullptr, "Already joined");
         mJoinThreadRunning = true;
-        mShutdownTrigger = RpcSession::FdTrigger::make();
+        mShutdownTrigger = FdTrigger::make();
         LOG_ALWAYS_FATAL_IF(mShutdownTrigger == nullptr, "Cannot create join signaler");
 
         mCtx = mRpcTransportCtxFactory->newServerCtx();
@@ -270,8 +271,8 @@ void RpcServer::establishConnection(sp<RpcServer>&& server, base::unique_fd clie
 
     RpcConnectionHeader header;
     if (status == OK) {
-        status = server->mShutdownTrigger->interruptableReadFully(client.get(), &header,
-                                                                  sizeof(header));
+        status = client->interruptableReadFully(server->mShutdownTrigger.get(), &header,
+                                                sizeof(header));
         if (status != OK) {
             ALOGE("Failed to read ID for client connecting to RPC server: %s",
                   statusToString(status).c_str());
@@ -296,8 +297,8 @@ void RpcServer::establishConnection(sp<RpcServer>&& server, base::unique_fd clie
                     .version = protocolVersion,
             };
 
-            status = server->mShutdownTrigger->interruptableWriteFully(client.get(), &response,
-                                                                       sizeof(response));
+            status = client->interruptableWriteFully(server->mShutdownTrigger.get(), &response,
+                                                     sizeof(response));
             if (status != OK) {
                 ALOGE("Failed to send new session response: %s", statusToString(status).c_str());
                 // still need to cleanup before we can return