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			96 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			96 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //
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| // StreamUtil.h
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| //
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| // Library: Foundation
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| // Package: Streams
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| // Module:  StreamUtil
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| //
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| // Stream implementation support.
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| //
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| // Copyright (c) 2005-2006, Applied Informatics Software Engineering GmbH.
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| // and Contributors.
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| //
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| // SPDX-License-Identifier:	BSL-1.0
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| //
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| 
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| 
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| #ifndef Foundation_StreamUtil_INCLUDED
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| #define Foundation_StreamUtil_INCLUDED
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| 
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| 
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| #include "Poco/Foundation.h"
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| 
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| 
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| // poco_ios_init
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| //
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| // This is a workaround for a bug in the Dinkumware
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| // implementation of iostreams.
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| //
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| // Calling basic_ios::init() multiple times for the
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| // same basic_ios instance results in a memory leak
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| // caused by the ios' locale being allocated more than
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| // once, each time overwriting the old pointer.
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| // This usually occurs in the following scenario:
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| //
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| // class MyStreamBuf: public std::streambuf
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| // {
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| //     ...
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| // };
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| //
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| // class MyIOS: public virtual std::ios
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| // {
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| // public:
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| //     MyIOS()
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| //     {
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| //         init(&_buf);
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| //     }
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| // protected:
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| //     MyStreamBuf _buf;
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| // };
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| //
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| // class MyIStream: public MyIOS, public std::istream
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| // {
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| //     ...
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| // };
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| //
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| // In this scenario, std::ios::init() is called twice
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| // (the first time by the MyIOS constructor, the second
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| // time by the std::istream constructor), resulting in
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| // two locale objects being allocated, the pointer second
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| // one overwriting the pointer to the first one and thus
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| // causing a memory leak.
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| //
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| // The workaround is to call init() only once for each
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| // stream object - by the istream, ostream or iostream
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| // constructor, and not calling init() in ios-derived
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| // base classes.
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| //
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| // Some stream implementations, however, require that
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| // init() is called in the MyIOS constructor.
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| // Therefore we replace each call to init() with
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| // the poco_ios_init macro defined below.
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| 
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| 
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| #if !defined(POCO_IOS_INIT_HACK)
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| 	// Microsoft Visual Studio with Dinkumware STL (but not STLport)
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| #	if defined(_MSC_VER) && (!defined(_STLP_MSVC) || defined(_STLP_NO_OWN_IOSTREAMS))
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| #		define POCO_IOS_INIT_HACK 1
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|     // QNX with Dinkumware but not GNU C++ Library
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| #	elif defined(__QNX__) && !defined(__GLIBCPP__)
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| #		define POCO_IOS_INIT_HACK 1
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| 	// Linux with Clang libc++
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| #   elif defined(__linux) && defined(_LIBCPP_VERSION)
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| #		define POCO_IOS_INIT_HACK 1
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| #	endif
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| #endif
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| 
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| 
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| #if defined(POCO_IOS_INIT_HACK)
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| #	define poco_ios_init(buf)
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| #else
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| #	define poco_ios_init(buf) init(buf)
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| #endif
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| 
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| 
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| #endif // Foundation_StreamUtil_INCLUDED
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