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 is an extension. It defines two streambufs: 20 // stdio_istreambuf, a read-only streambuf synchronized with a C stdio 21 // FILE object, and stdio_ostreambuf, a write-only streambuf 22 // synchronized with a C stdio FILE object. Note that neither 23 // stdio_istreambuf nor stdio_ostreambuf is a template; both classes 24 // are derived from basic_streambuf<char, char_traits<char> >. 25 26 // Note: the imbue() member function is a no-op. In particular, these 27 // classes assume that codecvt<char, char, mbstate_t> is always an identity 28 // transformation. This is true of the default locale, and of all locales 29 // defined for the C I/O library. If you need to use a locale where 30 // the codecvt<char, char, mbstate_t> facet performs a nontrivial 31 // conversion, then you should use basic_filebuf<> instead of stdio_istreambuf 32 // or stdio_ostreambuf. (If you don't understand what any of this means, 33 // then it's not a feature you need to worry about. Locales where 34 // codecvt<char, char, mbstate_t> does something nontrivial are a rare 35 // corner case.) 36 37 38 #ifndef _STLP_STDIO_STREAMBUF 39 #define _STLP_STDIO_STREAMBUF 40 41 #include <streambuf> 42 #include <cstdio> // For FILE. 43 44 _STLP_BEGIN_NAMESPACE 45 _STLP_MOVE_TO_PRIV_NAMESPACE 46 47 // Base class for features common to stdio_istreambuf and stdio_ostreambuf 48 class stdio_streambuf_base : 49 public basic_streambuf<char, char_traits<char> > /* FILE_basic_streambuf */ { 50 public: // Constructor, destructor. 51 // The argument may not be null. It must be an open file pointer. 52 stdio_streambuf_base(FILE*); 53 54 // The destructor flushes the stream, but does not close it. 55 ~stdio_streambuf_base(); 56 57 protected: // Virtual functions from basic_streambuf. 58 streambuf* setbuf(char*, streamsize); 59 60 pos_type seekoff(off_type, ios_base::seekdir, 61 ios_base::openmode 62 = ios_base::in | ios_base::out); 63 pos_type seekpos(pos_type, 64 ios_base::openmode 65 = ios_base::in | ios_base::out); 66 int sync(); 67 68 protected: 69 FILE* _M_file; 70 }; 71 72 class stdio_istreambuf : public stdio_streambuf_base { 73 public: // Constructor, destructor. stdio_istreambuf(FILE * __f)74 stdio_istreambuf(FILE* __f) : stdio_streambuf_base(__f) {} 75 ~stdio_istreambuf(); 76 77 protected: // Virtual functions from basic_streambuf. 78 streamsize showmanyc(); 79 int_type underflow(); 80 int_type uflow(); 81 virtual int_type pbackfail(int_type c = traits_type::eof()); 82 }; 83 84 class stdio_ostreambuf : public stdio_streambuf_base { 85 public: // Constructor, destructor. stdio_ostreambuf(FILE * __f)86 stdio_ostreambuf(FILE* __f) : stdio_streambuf_base(__f) {} 87 ~stdio_ostreambuf(); 88 89 protected: // Virtual functions from basic_streambuf. 90 streamsize showmanyc(); 91 int_type overflow(int_type c = traits_type::eof()); 92 }; 93 94 _STLP_MOVE_TO_STD_NAMESPACE 95 _STLP_END_NAMESPACE 96 97 #endif /* _STLP_STDIO_STREAMBUF */ 98 99 // Local Variables: 100 // mode:C++ 101 // End: 102