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Diffstat (limited to 'sandbox/win/src/shared_handles.h')
-rw-r--r-- | sandbox/win/src/shared_handles.h | 108 |
1 files changed, 0 insertions, 108 deletions
diff --git a/sandbox/win/src/shared_handles.h b/sandbox/win/src/shared_handles.h deleted file mode 100644 index 2c76bfb..0000000 --- a/sandbox/win/src/shared_handles.h +++ /dev/null @@ -1,108 +0,0 @@ -// Copyright (c) 2010 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 SANDBOX_SRC_SHARED_HANDLES_H__ -#define SANDBOX_SRC_SHARED_HANDLES_H__ - -#include "base/basictypes.h" - -#ifndef HANDLE -// We can provide our own windows compatilble handle definition, but -// in general we want to rely on the client of this api to include -// the proper windows headers. Note that we don't want to bring the -// whole <windows.h> into scope if we don't have to. -typedef void* HANDLE; -#endif - -namespace sandbox { - -// SharedHandles is a simple class to stash and find windows object handles -// given a raw block of memory which is shared between two processes. -// It addresses the need to communicate a handle value between two windows -// processes given that they are already sharing some memory. -// -// This class is not exposed directly to users of the sanbox API, instead -// we expose the wrapper methods TargetProcess::TransferHandle( ) and -// TargetServices::GetTransferHandle() -// -// Use it for a small number of items, since internaly uses linear seach -// -// The use is very simple. Given a shared memory between proces A and B: -// process A: -// HANDLE handle = SomeFunction(..); -// SharedHandles shared_handes; -// shared_handles.Init(memory) -// shared_handles.SetHandle(3, handle); -// -// process B: -// SharedHandles shared_handes; -// shared_handles.Init(memory) -// HANDLE handle = shared_handles.GetHandle(3); -// -// Note that '3' in this example is a unique id, that must be agreed before -// transfer -// -// Note2: While this class can be used in a single process, there are -// better alternatives such as STL -// -// Note3: Under windows a kernel object handle in one process does not -// make sense for another process unless there is a DuplicateHandle( ) -// call involved which this class DOES NOT do that for you. -// -// Note4: Under windows, shared memory when created is initialized to -// zeros always. If you are not using shared memory it is your responsability -// to zero it for the setter process and to copy it to the getter process. -class SharedHandles { - public: - SharedHandles(); - - // Initializes the shared memory for use. - // Pass the shared memory base and size. It will internally compute - // how many handles can it store. If initialization fails the return value - // is false. - bool Init(void* raw_mem, size_t size_bytes); - - // Sets a handle in the shared memory for transfer. - // Parameters: - // tag : an integer, different from zero that uniquely identfies the - // handle to transfer. - // handle: the handle value associated with 'tag' to tranfer - // Returns false if there is not enough space in the shared memory for - // this handle. - bool SetHandle(uint32 tag, HANDLE handle); - - // Gets a handle previously stored by SetHandle. - // Parameters: - // tag: an integer different from zero that uniquely identfies the handle - // to retrieve. - // *handle: output handle value if the call was succesful. - // If a handle with the provided tag is not found the return value is false. - // If the tag is found the return value is true. - bool GetHandle(uint32 tag, HANDLE* handle); - - private: - // A single item is the tuple handle/tag - struct SharedItem { - uint32 tag; - void* item; - }; - - // SharedMem is used to layout the memory as an array of SharedItems - struct SharedMem { - size_t max_items; - SharedItem* items; - }; - - // Finds an Item tuple provided the handle tag. - // Uses linear search because we expect the number of handles to be - // small (say less than ~100). - SharedItem* FindByTag(uint32 tag); - - SharedMem shared_; - DISALLOW_COPY_AND_ASSIGN(SharedHandles); -}; - -} // namespace sandbox - -#endif // SANDBOX_SRC_SHARED_HANDLES_H__ |