1 /* 2 * Copyright (c) 1999 3 * Silicon Graphics Computer Systems, Inc. 4 * 5 * Copyright (c) 1999 6 * Boris Fomitchev 7 * 8 * This material is provided "as is", with absolutely no warranty expressed 9 * or implied. Any use is at your own risk. 10 * 11 * Permission to use or copy this software for any purpose is hereby granted 12 * without fee, provided the above notices are retained on all copies. 13 * Permission to modify the code and to distribute modified code is granted, 14 * provided the above notices are retained, and a notice that the code was 15 * modified is included with the above copyright notice. 16 * 17 */ 18 19 // This header defines two streambufs: 20 // stdio_istreambuf, a read-only streambuf synchronized with a C stdio 21 // FILE object 22 // stdio_ostreambuf, a write-only streambuf synchronized with a C stdio 23 // FILE object. 24 // Note that neither stdio_istreambuf nor stdio_ostreambuf is a template; 25 // both classes are derived from basic_streambuf<char, char_traits<char> >. 26 27 // Note: the imbue() member function is a no-op. In particular, these 28 // classes assume that codecvt<char, char, mbstate_t> is always an identity 29 // transformation. This is true of the default locale, and of all locales 30 // defined for the C I/O library. If you need to use a locale where 31 // the codecvt<char, char, mbstate_t> facet performs a nontrivial 32 // conversion, then you should use basic_filebuf<> instead of stdio_istreambuf 33 // or stdio_ostreambuf. (If you don't understand what any of this means, 34 // then it's not a feature you need to worry about. Locales where 35 // codecvt<char, char, mbstate_t> does something nontrivial are a rare 36 // corner case.) 37 38 39 #ifndef _STLP_STDIO_STREAMBUF 40 #define _STLP_STDIO_STREAMBUF 41 42 #include <streambuf> 43 #include <cstdio> // For FILE. 44 45 _STLP_BEGIN_NAMESPACE 46 _STLP_MOVE_TO_PRIV_NAMESPACE 47 48 // Base class for features common to stdio_istreambuf and stdio_ostreambuf 49 class stdio_streambuf_base : 50 public basic_streambuf<char, char_traits<char> > /* FILE_basic_streambuf */ { 51 public: // Constructor, destructor. 52 // The argument may not be null. It must be an open file pointer. 53 stdio_streambuf_base(FILE*); 54 55 // The destructor flushes the stream, but does not close it. 56 ~stdio_streambuf_base(); 57 58 protected: // Virtual functions from basic_streambuf. 59 streambuf* setbuf(char*, streamsize); 60 61 pos_type seekoff(off_type, ios_base::seekdir, 62 ios_base::openmode 63 = ios_base::in | ios_base::out); 64 pos_type seekpos(pos_type, 65 ios_base::openmode 66 = ios_base::in | ios_base::out); 67 int sync(); 68 69 protected: 70 FILE* _M_file; 71 }; 72 73 class stdio_istreambuf : public stdio_streambuf_base { 74 public: // Constructor, destructor. 75 stdio_istreambuf(FILE* __f) : stdio_streambuf_base(__f) {} 76 ~stdio_istreambuf(); 77 78 protected: // Virtual functions from basic_streambuf. 79 streamsize showmanyc(); 80 int_type underflow(); 81 int_type uflow(); 82 virtual int_type pbackfail(int_type c = traits_type::eof()); 83 }; 84 85 class stdio_ostreambuf : public stdio_streambuf_base { 86 public: // Constructor, destructor. 87 stdio_ostreambuf(FILE* __f) : stdio_streambuf_base(__f) {} 88 ~stdio_ostreambuf(); 89 90 protected: // Virtual functions from basic_streambuf. 91 streamsize showmanyc(); 92 int_type overflow(int_type c = traits_type::eof()); 93 }; 94 95 _STLP_MOVE_TO_STD_NAMESPACE 96 _STLP_END_NAMESPACE 97 98 #endif /* _STLP_STDIO_STREAMBUF */ 99 100 // Local Variables: 101 // mode:C++ 102 // End: 103
