| Index: mojo/public/cpp/system/handle.h
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| diff --git a/mojo/public/cpp/system/handle.h b/mojo/public/cpp/system/handle.h
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| deleted file mode 100644
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| index 988e5e01875a9c957dbc595d9282f351d67eacd8..0000000000000000000000000000000000000000
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| --- a/mojo/public/cpp/system/handle.h
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| +++ /dev/null
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| @@ -1,251 +0,0 @@
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| -// 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 <mojo/result.h>
|
| -#include <mojo/system/handle.h>
|
| -#include <stdint.h>
|
| -
|
| -#include <limits>
|
| -
|
| -#include "mojo/public/cpp/system/macros.h"
|
| -
|
| -namespace mojo {
|
| -
|
| -// OVERVIEW
|
| -//
|
| -// |Handle| and |...Handle|:
|
| -//
|
| -// |Handle| is a simple, copyable wrapper for the C type |MojoHandle| (which is
|
| -// just an integer). Its purpose is to increase type-safety, not provide
|
| -// lifetime management. For the same purpose, we have trivial *subclasses* of
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| -// |Handle|, e.g., |MessagePipeHandle| and |DataPipeProducerHandle|. |Handle|
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| -// and its subclasses impose *no* extra overhead over using |MojoHandle|s
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| -// directly.
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| -//
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| -// Note that though we provide constructors for |Handle|/|...Handle| from a
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| -// |MojoHandle|, we do not provide, e.g., a constructor for |MessagePipeHandle|
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| -// from a |Handle|. This is for type safety: If we did, you'd then be able to
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| -// construct a |MessagePipeHandle| from, e.g., a |DataPipeProducerHandle| (since
|
| -// it's a |Handle|).
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| -//
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| -// |ScopedHandleBase| and |Scoped...Handle|:
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| -//
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| -// |ScopedHandleBase<HandleType>| is a templated scoped wrapper, for the handle
|
| -// types above (in the same sense that a C++11 |unique_ptr<T>| is a scoped
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| -// wrapper for a |T*|). It provides lifetime management, closing its owned
|
| -// handle on destruction. It also provides (emulated) move semantics, again
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| -// along the lines of C++11's |unique_ptr| (and exactly like Chromium's
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| -// |scoped_ptr|).
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| -//
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| -// |ScopedHandle| is just (a typedef of) a |ScopedHandleBase<Handle>|.
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| -// Similarly, |ScopedMessagePipeHandle| is just a
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| -// |ScopedHandleBase<MessagePipeHandle>|. Etc. Note that a
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| -// |ScopedMessagePipeHandle| is *not* a (subclass of) |ScopedHandle|.
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| -//
|
| -// Wrapper functions:
|
| -//
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| -// We provide simple wrappers for the |Mojo...()| functions (declared in various
|
| -// mojo/public/c/include/mojo/system/*.h -- see those file for details on
|
| -// individual functions).
|
| -//
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| -// The general guideline is functions that imply ownership transfer of a handle
|
| -// should take (or produce) an appropriate |Scoped...Handle|, while those that
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| -// don't take a |...Handle|. For example, |CreateMessagePipe()| has two
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| -// |ScopedMessagePipe| "out" parameters, whereas |Wait()| and |WaitMany()| take
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| -// |Handle| parameters. Some, have both: e.g., |DuplicatedBuffer()| takes a
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| -// suitable (unscoped) handle (e.g., |SharedBufferHandle|) "in" parameter and
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| -// produces a suitable scoped handle (e.g., |ScopedSharedBufferHandle| a.k.a.
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| -// |ScopedHandleBase<SharedBufferHandle>|) as an "out" parameter.
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| -//
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| -// An exception are some of the |...Raw()| functions. E.g., |CloseRaw()| takes a
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| -// |Handle|, leaving the user to discard the wrapper.
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| -//
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| -// ScopedHandleBase ------------------------------------------------------------
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| -
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| -// Scoper for the actual handle types defined further below. It's move-only,
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| -// like the C++11 |unique_ptr|.
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| -template <class HandleType>
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| -class ScopedHandleBase {
|
| - public:
|
| - ScopedHandleBase() {}
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| - explicit ScopedHandleBase(HandleType handle) : handle_(handle) {}
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| - ~ScopedHandleBase() { CloseIfNecessary(); }
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| -
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| - template <class CompatibleHandleType>
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| - explicit ScopedHandleBase(ScopedHandleBase<CompatibleHandleType> other)
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| - : handle_(other.release()) {}
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| -
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| - // Move-only constructor and operator=.
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| - ScopedHandleBase(ScopedHandleBase&& other) : handle_(other.release()) {}
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| - ScopedHandleBase& operator=(ScopedHandleBase&& other) {
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| - if (&other != this) {
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| - CloseIfNecessary();
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| - handle_ = other.release();
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| - }
|
| - return *this;
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| - }
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| -
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| - const HandleType& get() const { return handle_; }
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| -
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| - template <typename PassedHandleType>
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| - static ScopedHandleBase<HandleType> From(
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| - ScopedHandleBase<PassedHandleType> other) {
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| - static_assert(
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| - sizeof(static_cast<PassedHandleType*>(static_cast<HandleType*>(0))),
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| - "HandleType is not a subtype of PassedHandleType");
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| - return ScopedHandleBase<HandleType>(
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| - static_cast<HandleType>(other.release().value()));
|
| - }
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| -
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| - void swap(ScopedHandleBase& other) { handle_.swap(other.handle_); }
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| -
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| - HandleType release() MOJO_WARN_UNUSED_RESULT {
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| - HandleType rv;
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| - rv.swap(handle_);
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| - return rv;
|
| - }
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| -
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| - void reset(HandleType handle = HandleType()) {
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| - CloseIfNecessary();
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| - handle_ = handle;
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| - }
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| -
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| - bool is_valid() const { return handle_.is_valid(); }
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| -
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| - private:
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| - void CloseIfNecessary() {
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| - if (!handle_.is_valid())
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| - return;
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| - MojoResult result = MojoClose(handle_.value());
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| - MOJO_ALLOW_UNUSED_LOCAL(result);
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| - assert(result == MOJO_RESULT_OK);
|
| - }
|
| -
|
| - HandleType handle_;
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| -
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| - MOJO_MOVE_ONLY_TYPE(ScopedHandleBase);
|
| -};
|
| -
|
| -template <typename HandleType>
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| -inline ScopedHandleBase<HandleType> MakeScopedHandle(HandleType handle) {
|
| - return ScopedHandleBase<HandleType>(handle);
|
| -}
|
| -
|
| -// Handle ----------------------------------------------------------------------
|
| -
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| -const MojoHandle kInvalidHandleValue = MOJO_HANDLE_INVALID;
|
| -
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| -// Wrapper base class for |MojoHandle|.
|
| -class Handle {
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| - public:
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| - Handle() : value_(kInvalidHandleValue) {}
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| - explicit Handle(MojoHandle value) : value_(value) {}
|
| - ~Handle() {}
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| -
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| - void swap(Handle& other) {
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| - MojoHandle temp = value_;
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| - value_ = other.value_;
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| - other.value_ = temp;
|
| - }
|
| -
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| - bool is_valid() const { return value_ != kInvalidHandleValue; }
|
| -
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| - const MojoHandle& value() const { return value_; }
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| - MojoHandle* mutable_value() { return &value_; }
|
| - void set_value(MojoHandle value) { value_ = value; }
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| -
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| - private:
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| - MojoHandle value_;
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| -
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| - // Copying and assignment allowed.
|
| -};
|
| -
|
| -// Should have zero overhead.
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| -static_assert(sizeof(Handle) == sizeof(MojoHandle), "Bad size for C++ Handle");
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| -
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| -// The scoper should also impose no more overhead.
|
| -typedef ScopedHandleBase<Handle> ScopedHandle;
|
| -static_assert(sizeof(ScopedHandle) == sizeof(Handle),
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| - "Bad size for C++ ScopedHandle");
|
| -
|
| -// |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>
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| -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();
|
| -}
|
| -
|
| -// Rights and duplication/replacement ------------------------------------------
|
| -
|
| -// |handle| must be valid.
|
| -inline MojoHandleRights GetRights(Handle handle) {
|
| - assert(handle.is_valid());
|
| - MojoHandleRights rights = MOJO_HANDLE_RIGHT_NONE;
|
| - MojoResult result = MojoGetRights(handle.value(), &rights);
|
| - MOJO_ALLOW_UNUSED_LOCAL(result);
|
| - assert(result == MOJO_RESULT_OK);
|
| - return rights;
|
| -}
|
| -
|
| -// |HandleType| should be some subclass of |Handle|; this is templated so that
|
| -// it will work with multiple handle types. |*handle| must be valid. Returns
|
| -// true on success or false on failure (in which case |*handle| is reset).
|
| -template <class HandleType>
|
| -inline bool ReplaceHandleWithReducedRights(ScopedHandleBase<HandleType>* handle,
|
| - MojoHandleRights rights_to_remove) {
|
| - assert(handle);
|
| - assert(handle->is_valid());
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| - HandleType raw_handle = handle->release();
|
| - HandleType new_raw_handle;
|
| - if (MojoReplaceHandleWithReducedRights(raw_handle.value(), rights_to_remove,
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| - new_raw_handle.mutable_value()) !=
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| - MOJO_RESULT_OK) {
|
| - assert(false); // This really shouldn't happen.
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| - CloseRaw(raw_handle);
|
| - return false;
|
| - }
|
| - // Otherwise, |raw_handle| is invalidated.
|
| - handle->reset(new_raw_handle);
|
| - return true;
|
| -}
|
| -
|
| -template <class HandleType>
|
| -inline ScopedHandleBase<HandleType> DuplicateHandleWithReducedRights(
|
| - HandleType handle,
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| - MojoHandleRights rights_to_remove) {
|
| - assert(handle.is_valid());
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| - HandleType new_handle;
|
| - MojoResult result = MojoDuplicateHandleWithReducedRights(
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| - handle.value(), rights_to_remove, new_handle.mutable_value());
|
| - MOJO_ALLOW_UNUSED_LOCAL(result);
|
| - assert(result == MOJO_RESULT_OK);
|
| - return MakeScopedHandle(new_handle);
|
| -}
|
| -
|
| -template <class HandleType>
|
| -inline ScopedHandleBase<HandleType> DuplicateHandle(HandleType handle) {
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| - HandleType new_handle;
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| - MojoResult result =
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| - MojoDuplicateHandle(handle.value(), new_handle.mutable_value());
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| - MOJO_ALLOW_UNUSED_LOCAL(result);
|
| - assert(result == MOJO_RESULT_OK);
|
| - return MakeScopedHandle(new_handle);
|
| -}
|
| -
|
| -} // namespace mojo
|
| -
|
| -#endif // MOJO_PUBLIC_CPP_SYSTEM_HANDLE_H_
|
|
|