1 | // |
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2 | // StreamUtil.h |
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3 | // |
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4 | // $Id: //poco/1.3/Foundation/include/Poco/StreamUtil.h#2 $ |
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5 | // |
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6 | // Library: Foundation |
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7 | // Package: Streams |
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8 | // Module: StreamUtil |
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9 | // |
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10 | // Stream implementation support. |
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11 | // |
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12 | // Copyright (c) 2005-2006, Applied Informatics Software Engineering GmbH. |
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13 | // and Contributors. |
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14 | // |
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15 | // Permission is hereby granted, free of charge, to any person or organization |
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16 | // obtaining a copy of the software and accompanying documentation covered by |
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17 | // this license (the "Software") to use, reproduce, display, distribute, |
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18 | // execute, and transmit the Software, and to prepare derivative works of the |
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19 | // Software, and to permit third-parties to whom the Software is furnished to |
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20 | // do so, all subject to the following: |
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21 | // |
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22 | // The copyright notices in the Software and this entire statement, including |
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23 | // the above license grant, this restriction and the following disclaimer, |
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24 | // must be included in all copies of the Software, in whole or in part, and |
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25 | // all derivative works of the Software, unless such copies or derivative |
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26 | // works are solely in the form of machine-executable object code generated by |
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27 | // a source language processor. |
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28 | // |
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29 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
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30 | // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
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31 | // FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT |
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32 | // SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE |
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33 | // FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, |
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34 | // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
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35 | // DEALINGS IN THE SOFTWARE. |
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36 | // |
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37 | |
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38 | |
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39 | #ifndef Foundation_StreamUtil_INCLUDED |
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40 | #define Foundation_StreamUtil_INCLUDED |
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41 | |
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42 | |
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43 | #include "Poco/Foundation.h" |
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44 | |
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45 | |
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46 | // poco_ios_init |
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47 | // |
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48 | // This is a workaround for a bug in the Dinkumware |
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49 | // implementation of iostreams. |
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50 | // |
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51 | // Calling basic_ios::init() multiple times for the |
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52 | // same basic_ios instance results in a memory leak |
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53 | // caused by the ios' locale being allocated more than |
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54 | // once, each time overwriting the old pointer. |
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55 | // This usually occurs in the following scenario: |
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56 | // |
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57 | // class MyStreamBuf: public std::streambuf |
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58 | // { |
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59 | // ... |
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60 | // }; |
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61 | // |
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62 | // class MyIOS: public virtual std::ios |
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63 | // { |
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64 | // public: |
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65 | // MyIOS() |
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66 | // { |
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67 | // init(&_buf); |
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68 | // } |
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69 | // protected: |
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70 | // MyStreamBuf _buf; |
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71 | // }; |
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72 | // |
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73 | // class MyIStream: public MyIOS, public std::istream |
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74 | // { |
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75 | // ... |
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76 | // }; |
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77 | // |
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78 | // In this scenario, std::ios::init() is called twice |
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79 | // (the first time by the MyIOS constructor, the second |
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80 | // time by the std::istream constructor), resulting in |
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81 | // two locale objects being allocated, the pointer second |
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82 | // one overwriting the pointer to the first one and thus |
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83 | // causing a memory leak. |
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84 | // |
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85 | // The workaround is to call init() only once for each |
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86 | // stream object - by the istream, ostream or iostream |
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87 | // constructor, and not calling init() in ios-derived |
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88 | // base classes. |
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89 | // |
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90 | // Some stream implementations, however, require that |
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91 | // init() is called in the MyIOS constructor. |
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92 | // Therefore we replace each call to init() with |
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93 | // the poco_ios_init macro defined below. |
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94 | |
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95 | |
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96 | #if !defined(POCO_IOS_INIT_HACK) |
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97 | // Microsoft Visual Studio with Dinkumware STL (but not STLport) |
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98 | # if defined(_MSC_VER) && (!defined(_STLP_MSVC) || defined(_STLP_NO_OWN_IOSTREAMS)) |
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99 | # define POCO_IOS_INIT_HACK 1 |
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100 | // QNX with Dinkumware but not GNU C++ Library |
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101 | # elif defined(__QNX__) && !defined(__GLIBCPP__) |
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102 | # define POCO_IOS_INIT_HACK 1 |
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103 | # endif |
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104 | #endif |
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105 | |
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106 | |
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107 | #if defined(POCO_IOS_INIT_HACK) |
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108 | # define poco_ios_init(buf) |
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109 | #else |
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110 | # define poco_ios_init(buf) init(buf) |
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111 | #endif |
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112 | |
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113 | |
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114 | #endif // Foundation_StreamUtil_INCLUDED |
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