adb: fdevent: extract Create/Destroy from fdevent_context_poll.

am: 33944a2742

Change-Id: Ie999135e7a60d01848e3ccee13d93135ab2170e8

adb/fdevent/fdevent.cpp

@@ -24,6 +24,7 @@
 #include <android-base/stringprintf.h>
 #include <android-base/threads.h>
 
+#include "adb_utils.h"
 #include "fdevent.h"
 #include "fdevent_poll.h"
 
@@ -48,6 +49,40 @@ std::string dump_fde(const fdevent* fde) {
                                        state.c_str());
 }
 
+fdevent* fdevent_context::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();
+    }
+
+    this->Register(fde);
+    return fde;
+}
+
+unique_fd fdevent_context::Destroy(fdevent* fde) {
+    CheckMainThread();
+    if (!fde) {
+        return {};
+    }
+
+    this->Unregister(fde);
+
+    unique_fd result = std::move(fde->fd);
+    delete fde;
+    return result;
+}
+
 void fdevent_context::CheckMainThread() {
     if (main_thread_id_) {
         CHECK_EQ(*main_thread_id_, android::base::GetThreadId());

adb/fdevent/fdevent.h

@@ -55,11 +55,19 @@ struct fdevent_context {
     virtual ~fdevent_context() = default;
 
     // Allocate and initialize a new fdevent object.
-    virtual fdevent* Create(unique_fd fd, std::variant<fd_func, fd_func2> func, void* arg) = 0;
+    fdevent* Create(unique_fd fd, std::variant<fd_func, fd_func2> func, void* arg);
 
     // Deallocate an fdevent object, returning the file descriptor that was owned by it.
-    virtual unique_fd Destroy(fdevent* fde) = 0;
+    unique_fd Destroy(fdevent* fde);
 
+  protected:
+    // Register an fdevent that is being created by Create with the fdevent_context.
+    virtual void Register(fdevent* fde) = 0;
+
+    // Unregister an fdevent that is being destroyed by Destroy with the fdevent_context.
+    virtual void Unregister(fdevent* fde) = 0;
+
+  public:
     // Change which events should cause notifications.
     virtual void Set(fdevent* fde, unsigned events) = 0;
     virtual void Add(fdevent* fde, unsigned events) = 0;
@@ -98,6 +106,7 @@ struct fdevent_context {
     std::atomic<bool> terminate_loop_ = false;
 
   private:
+    uint64_t fdevent_id_ = 0;
     std::mutex run_queue_mutex_;
     std::deque<std::function<void()>> run_queue_ GUARDED_BY(run_queue_mutex_);
 };

adb/fdevent/fdevent_poll.cpp

@@ -78,38 +78,14 @@ fdevent_context_poll::~fdevent_context_poll() {
     this->Destroy(this->interrupt_fde_);
 }
 
-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();
-    }
+void fdevent_context_poll::Register(fdevent* fde) {
     auto pair = poll_node_map_.emplace(fde->fd.get(), PollNode(fde));
     CHECK(pair.second) << "install existing fd " << fde->fd.get();
-
-    return fde;
 }
 
-unique_fd fdevent_context_poll::Destroy(fdevent* fde) {
-    CheckMainThread();
-    if (!fde) {
-        return {};
-    }
-
-    unique_fd result = std::move(fde->fd);
+void fdevent_context_poll::Unregister(fdevent* fde) {
     if (fde->state & FDE_ACTIVE) {
-        poll_node_map_.erase(result.get());
+        poll_node_map_.erase(fde->fd.get());
 
         if (fde->state & FDE_PENDING) {
             pending_list_.remove(fde);
@@ -117,9 +93,6 @@ unique_fd fdevent_context_poll::Destroy(fdevent* fde) {
         fde->state = 0;
         fde->events = 0;
     }
-
-    delete fde;
-    return result;
 }
 
 void fdevent_context_poll::Set(fdevent* fde, unsigned events) {

adb/fdevent/fdevent_poll.h

@@ -48,8 +48,8 @@ struct fdevent_context_poll : public fdevent_context {
     fdevent_context_poll();
     virtual ~fdevent_context_poll();
 
-    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 Register(fdevent* fde) final;
+    virtual void Unregister(fdevent* fde) final;
 
     virtual void Set(fdevent* fde, unsigned events) final;
     virtual void Add(fdevent* fde, unsigned events) final;
@@ -68,7 +68,6 @@ struct fdevent_context_poll : public fdevent_context {
     // That's why we don't need a lock for fdevent.
     std::unordered_map<int, PollNode> poll_node_map_;
     std::list<fdevent*> pending_list_;
-    uint64_t fdevent_id_ = 0;
 
     unique_fd interrupt_fd_;
     fdevent* interrupt_fde_ = nullptr;