Update mojo sdk to rev 59145288bae55b0fce4276b017df6a1117bcf00f

mojo/public/cpp/system/handle.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MOJO_PUBLIC_CPP_SYSTEM_HANDLE_H_
 #define MOJO_PUBLIC_CPP_SYSTEM_HANDLE_H_
 
 #include <assert.h>
 #include <limits>
 
@@ skipping 168 matching lines @@
 };
 
 // Should have zero overhead.
 static_assert(sizeof(Handle) == sizeof(MojoHandle), "Bad size for C++ Handle");
 
 // The scoper should also impose no more overhead.
 typedef ScopedHandleBase<Handle> ScopedHandle;
 static_assert(sizeof(ScopedHandle) == sizeof(Handle),
               "Bad size for C++ ScopedHandle");
 
+// TODO(jimbe): Remove this function
 inline MojoResult Wait(Handle handle,
                        MojoHandleSignals signals,
                        MojoDeadline deadline) {
   return MojoWait(handle.value(), signals, deadline);
 }
 
+inline MojoResult Wait(Handle handle,
+                       MojoHandleSignals signals,
+                       MojoDeadline deadline,
+                       MojoHandleSignalsState* signals_state) {
+  return MojoNewWait(handle.value(), signals, deadline, signals_state);
+}
+
+// TODO(jimbe): Remove this function
 // |HandleVectorType| and |FlagsVectorType| should be similar enough to
 // |std::vector<Handle>| and |std::vector<MojoHandleSignals>|, respectively:
 //  - They should have a (const) |size()| method that returns an unsigned type.
 //  - They must provide contiguous storage, with access via (const) reference to
 //    that storage provided by a (const) |operator[]()| (by reference).
 template <class HandleVectorType, class FlagsVectorType>
 inline MojoResult WaitMany(const HandleVectorType& handles,
                            const FlagsVectorType& signals,
                            MojoDeadline deadline) {
   if (signals.size() != handles.size())
     return MOJO_RESULT_INVALID_ARGUMENT;
   if (handles.size() > std::numeric_limits<uint32_t>::max())
     return MOJO_RESULT_OUT_OF_RANGE;
 
   if (handles.size() == 0)
     return MojoWaitMany(nullptr, nullptr, 0, deadline);
 
   const Handle& first_handle = handles[0];
   const MojoHandleSignals& first_signals = signals[0];
   return MojoWaitMany(
       reinterpret_cast<const MojoHandle*>(&first_handle),
       reinterpret_cast<const MojoHandleSignals*>(&first_signals),
       static_cast<uint32_t>(handles.size()),
       deadline);
 }
 
+const uint32_t kInvalidWaitManyIndexValue = static_cast<uint32_t>(-1);
+
+// Simplify the interpretation of the output from |MojoWaitMany()|.
+class WaitManyResult {
+ public:
+  explicit WaitManyResult(MojoResult mojo_wait_many_result)
+      : result(mojo_wait_many_result), index(kInvalidWaitManyIndexValue) {}
+
+  WaitManyResult(MojoResult mojo_wait_many_result, uint32_t result_index)
+      : result(mojo_wait_many_result), index(result_index) {}
+
+  // A valid handle index is always returned if |WaitMany()| succeeds, but may
+  // or may not be returned if |WaitMany()| returns an error. Use this helper
+  // function to check if |index| is a valid index into the handle array.
+  bool IsIndexValid() const { return index != kInvalidWaitManyIndexValue; }
+
+  // The |signals_states| array is always returned by |WaitMany()| on success,
+  // but may or may not be returned if |WaitMany()| returns an error. Use this
+  // helper function to check if |signals_states| holds valid data.
+  bool AreSignalsStatesValid() const {
+    return result != MOJO_RESULT_INVALID_ARGUMENT &&
+           result != MOJO_RESULT_RESOURCE_EXHAUSTED;
+  }
+
+  MojoResult result;
+  uint32_t index;
+};
+
+// |HandleVectorType| and |FlagsVectorType| should be similar enough to
+// |std::vector<Handle>| and |std::vector<MojoHandleSignals>|, respectively:
+//  - They should have a (const) |size()| method that returns an unsigned type.
+//  - They must provide contiguous storage, with access via (const) reference to
+//    that storage provided by a (const) |operator[]()| (by reference).
+template <class HandleVectorType,
+          class FlagsVectorType,
+          class SignalsStateVectorType>
+inline WaitManyResult WaitMany(const HandleVectorType& handles,
+                               const FlagsVectorType& signals,
+                               MojoDeadline deadline,
+                               SignalsStateVectorType* signals_states) {
+  if (signals.size() != handles.size() ||
+      (signals_states && signals_states->size() != signals.size()))
+    return WaitManyResult(MOJO_RESULT_INVALID_ARGUMENT);
+  if (handles.size() >= kInvalidWaitManyIndexValue)
+    return WaitManyResult(MOJO_RESULT_RESOURCE_EXHAUSTED);
+
+  if (handles.size() == 0) {
+    return WaitManyResult(
+        MojoNewWaitMany(nullptr, nullptr, 0, deadline, nullptr, nullptr));
+  }
+
+  uint32_t result_index = kInvalidWaitManyIndexValue;
+  const Handle& first_handle = handles[0];
+  const MojoHandleSignals& first_signals = signals[0];
+  MojoHandleSignalsState* first_state =
+      signals_states ? &(*signals_states)[0] : nullptr;
+  MojoResult result =
+      MojoNewWaitMany(reinterpret_cast<const MojoHandle*>(&first_handle),
+                      &first_signals, static_cast<uint32_t>(handles.size()),
+                      deadline, &result_index, first_state);
+  return WaitManyResult(result, result_index);
+}
+
+// C++ 4.10, regarding pointer conversion, says that an integral null pointer
+// constant can be converted to |std::nullptr_t| (which is a typedef for
+// |decltype(nullptr)|). The opposite direction is not allowed.
+template <class HandleVectorType, class FlagsVectorType>
+inline WaitManyResult WaitMany(const HandleVectorType& handles,
+                               const FlagsVectorType& signals,
+                               MojoDeadline deadline,
+                               decltype(nullptr) signals_states) {
+  if (signals.size() != handles.size())
+    return WaitManyResult(MOJO_RESULT_INVALID_ARGUMENT);
+  if (handles.size() >= kInvalidWaitManyIndexValue)
+    return WaitManyResult(MOJO_RESULT_OUT_OF_RANGE);
+
+  if (handles.size() == 0) {
+    return WaitManyResult(
+        MojoNewWaitMany(nullptr, nullptr, 0, deadline, nullptr, nullptr));
+  }
+
+  uint32_t result_index = kInvalidWaitManyIndexValue;
+  const Handle& first_handle = handles[0];
+  const MojoHandleSignals& first_signals = signals[0];
+  MojoResult result = MojoNewWaitMany(
+      reinterpret_cast<const MojoHandle*>(&first_handle), &first_signals,
+      static_cast<uint32_t>(handles.size()), deadline, &result_index, nullptr);
+  return WaitManyResult(result, result_index);
+}
+
 // |Close()| takes ownership of the handle, since it'll invalidate it.
 // Note: There's nothing to do, since the argument will be destroyed when it
 // goes out of scope.
 template <class HandleType>
 inline void Close(ScopedHandleBase<HandleType> /*handle*/) {
 }
 
 // Most users should typically use |Close()| (above) instead.
 inline MojoResult CloseRaw(Handle handle) {
   return MojoClose(handle.value());
 }
 
 // Strict weak ordering, so that |Handle|s can be used as keys in |std::map|s,
 inline bool operator<(const Handle a, const Handle b) {
   return a.value() < b.value();
 }
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_SYSTEM_HANDLE_H_