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Diffstat (limited to 'ipc/ipc_message.h')
-rw-r--r-- | ipc/ipc_message.h | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/ipc/ipc_message.h b/ipc/ipc_message.h new file mode 100644 index 0000000..6357c0b --- /dev/null +++ b/ipc/ipc_message.h @@ -0,0 +1,279 @@ +// Copyright (c) 2006-2008 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 IPC_IPC_MESSAGE_H__ +#define IPC_IPC_MESSAGE_H__ + +#include <string> + +#include "base/basictypes.h" +#include "base/pickle.h" + +#ifndef NDEBUG +#define IPC_MESSAGE_LOG_ENABLED +#endif + +#if defined(OS_POSIX) +#include "base/ref_counted.h" +#endif + +namespace base { +class FileDescriptor; +} + +class FileDescriptorSet; + +namespace IPC { + +//------------------------------------------------------------------------------ + +class Channel; +class Message; +struct LogData; + +class Message : public Pickle { + public: + // Implemented by objects that can send IPC messages across a channel. + class Sender { + public: + virtual ~Sender() {} + + // Sends the given IPC message. The implementor takes ownership of the + // given Message regardless of whether or not this method succeeds. This + // is done to make this method easier to use. Returns true on success and + // false otherwise. + virtual bool Send(Message* msg) = 0; + }; + + enum PriorityValue { + PRIORITY_LOW = 1, + PRIORITY_NORMAL, + PRIORITY_HIGH + }; + + virtual ~Message(); + + Message(); + + // Initialize a message with a user-defined type, priority value, and + // destination WebView ID. + Message(int32 routing_id, uint16 type, PriorityValue priority); + + // Initializes a message from a const block of data. The data is not copied; + // instead the data is merely referenced by this message. Only const methods + // should be used on the message when initialized this way. + Message(const char* data, int data_len); + + Message(const Message& other); + Message& operator=(const Message& other); + + PriorityValue priority() const { + return static_cast<PriorityValue>(header()->flags & PRIORITY_MASK); + } + + // True if this is a synchronous message. + bool is_sync() const { + return (header()->flags & SYNC_BIT) != 0; + } + + // Set this on a reply to a synchronous message. + void set_reply() { + header()->flags |= REPLY_BIT; + } + + bool is_reply() const { + return (header()->flags & REPLY_BIT) != 0; + } + + // Set this on a reply to a synchronous message to indicate that no receiver + // was found. + void set_reply_error() { + header()->flags |= REPLY_ERROR_BIT; + } + + bool is_reply_error() const { + return (header()->flags & REPLY_ERROR_BIT) != 0; + } + + // Normally when a receiver gets a message and they're blocked on a + // synchronous message Send, they buffer a message. Setting this flag causes + // the receiver to be unblocked and the message to be dispatched immediately. + void set_unblock(bool unblock) { + if (unblock) { + header()->flags |= UNBLOCK_BIT; + } else { + header()->flags &= ~UNBLOCK_BIT; + } + } + + bool should_unblock() const { + return (header()->flags & UNBLOCK_BIT) != 0; + } + + // Tells the receiver that the caller is pumping messages while waiting + // for the result. + bool is_caller_pumping_messages() const { + return (header()->flags & PUMPING_MSGS_BIT) != 0; + } + + uint16 type() const { + return header()->type; + } + + int32 routing_id() const { + return header()->routing; + } + + void set_routing_id(int32 new_id) { + header()->routing = new_id; + } + + template<class T> + static bool Dispatch(const Message* msg, T* obj, void (T::*func)()) { + (obj->*func)(); + return true; + } + + template<class T> + static bool Dispatch(const Message* msg, T* obj, void (T::*func)() const) { + (obj->*func)(); + return true; + } + + template<class T> + static bool Dispatch(const Message* msg, T* obj, + void (T::*func)(const Message&)) { + (obj->*func)(*msg); + return true; + } + + template<class T> + static bool Dispatch(const Message* msg, T* obj, + void (T::*func)(const Message&) const) { + (obj->*func)(*msg); + return true; + } + + // Used for async messages with no parameters. + static void Log(const Message* msg, std::wstring* l) { + } + + // Find the end of the message data that starts at range_start. Returns NULL + // if the entire message is not found in the given data range. + static const char* FindNext(const char* range_start, const char* range_end) { + return Pickle::FindNext(sizeof(Header), range_start, range_end); + } + +#if defined(OS_POSIX) + // On POSIX, a message supports reading / writing FileDescriptor objects. + // This is used to pass a file descriptor to the peer of an IPC channel. + + // Add a descriptor to the end of the set. Returns false iff the set is full. + bool WriteFileDescriptor(const base::FileDescriptor& descriptor); + // Get a file descriptor from the message. Returns false on error. + // iter: a Pickle iterator to the current location in the message. + bool ReadFileDescriptor(void** iter, base::FileDescriptor* descriptor) const; +#endif + +#ifdef IPC_MESSAGE_LOG_ENABLED + // Adds the outgoing time from Time::Now() at the end of the message and sets + // a bit to indicate that it's been added. + void set_sent_time(int64 time); + int64 sent_time() const; + + void set_received_time(int64 time) const; + int64 received_time() const { return received_time_; } + void set_output_params(const std::wstring& op) const { output_params_ = op; } + const std::wstring& output_params() const { return output_params_; } + // The following four functions are needed so we can log sync messages with + // delayed replies. We stick the log data from the sent message into the + // reply message, so that when it's sent and we have the output parameters + // we can log it. As such, we set a flag on the sent message to not log it. + void set_sync_log_data(LogData* data) const { log_data_ = data; } + LogData* sync_log_data() const { return log_data_; } + void set_dont_log() const { dont_log_ = true; } + bool dont_log() const { return dont_log_; } +#endif + + protected: + friend class Channel; + friend class MessageReplyDeserializer; + friend class SyncMessage; + + void set_sync() { + header()->flags |= SYNC_BIT; + } + + // flags + enum { + PRIORITY_MASK = 0x0003, + SYNC_BIT = 0x0004, + REPLY_BIT = 0x0008, + REPLY_ERROR_BIT = 0x0010, + UNBLOCK_BIT = 0x0020, + PUMPING_MSGS_BIT= 0x0040, + HAS_SENT_TIME_BIT = 0x0080, + }; + +#pragma pack(push, 2) + struct Header : Pickle::Header { + int32 routing; // ID of the view that this message is destined for + uint16 type; // specifies the user-defined message type + uint16 flags; // specifies control flags for the message +#if defined(OS_POSIX) + uint32 num_fds; // the number of descriptors included with this message +#endif + }; +#pragma pack(pop) + + Header* header() { + return headerT<Header>(); + } + const Header* header() const { + return headerT<Header>(); + } + + void InitLoggingVariables(); + +#if defined(OS_POSIX) + // The set of file descriptors associated with this message. + scoped_refptr<FileDescriptorSet> file_descriptor_set_; + + // Ensure that a FileDescriptorSet is allocated + void EnsureFileDescriptorSet(); + + FileDescriptorSet* file_descriptor_set() { + EnsureFileDescriptorSet(); + return file_descriptor_set_.get(); + } + const FileDescriptorSet* file_descriptor_set() const { + return file_descriptor_set_.get(); + } +#endif + +#ifdef IPC_MESSAGE_LOG_ENABLED + // Used for logging. + mutable int64 received_time_; + mutable std::wstring output_params_; + mutable LogData* log_data_; + mutable bool dont_log_; +#endif +}; + +//------------------------------------------------------------------------------ + +} // namespace IPC + +enum SpecialRoutingIDs { + // indicates that we don't have a routing ID yet. + MSG_ROUTING_NONE = -2, + + // indicates a general message not sent to a particular tab. + MSG_ROUTING_CONTROL = kint32max, +}; + +#define IPC_REPLY_ID 0xFFF0 // Special message id for replies +#define IPC_LOGGING_ID 0xFFF1 // Special message id for logging + +#endif // IPC_IPC_MESSAGE_H__ |