1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <fstream> 11 12 // pos_type seekoff(off_type off, ios_base::seekdir way, 13 // ios_base::openmode which = ios_base::in | ios_base::out); 14 // pos_type seekpos(pos_type sp, 15 // ios_base::openmode which = ios_base::in | ios_base::out); 16 17 // This test is not entirely portable 18 19 #include <fstream> 20 #include <cassert> 21 22 template <class CharT> 23 struct test_buf 24 : public std::basic_filebuf<CharT> 25 { 26 typedef std::basic_filebuf<CharT> base; 27 typedef typename base::char_type char_type; 28 typedef typename base::int_type int_type; 29 typedef typename base::pos_type pos_type; 30 31 char_type* eback() const {return base::eback();} 32 char_type* gptr() const {return base::gptr();} 33 char_type* egptr() const {return base::egptr();} 34 void gbump(int n) {base::gbump(n);} 35 36 virtual int_type underflow() {return base::underflow();} 37 }; 38 39 int main() 40 { 41 { 42 char buf[10]; 43 typedef std::filebuf::pos_type pos_type; 44 std::filebuf f; 45 f.pubsetbuf(buf, sizeof(buf)); 46 assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out 47 | std::ios_base::trunc) != 0); 48 assert(f.is_open()); 49 f.sputn("abcdefghijklmnopqrstuvwxyz", 26); 50 assert(buf[0] == 'v'); 51 pos_type p = f.pubseekoff(-15, std::ios_base::cur); 52 assert(p == 11); 53 assert(f.sgetc() == 'l'); 54 f.pubseekoff(0, std::ios_base::beg); 55 assert(f.sgetc() == 'a'); 56 f.pubseekoff(-1, std::ios_base::end); 57 assert(f.sgetc() == 'z'); 58 assert(f.pubseekpos(p) == p); 59 assert(f.sgetc() == 'l'); 60 } 61 std::remove("seekoff.dat"); 62 { 63 wchar_t buf[10]; 64 typedef std::filebuf::pos_type pos_type; 65 std::wfilebuf f; 66 f.pubsetbuf(buf, sizeof(buf)/sizeof(buf[0])); 67 assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out 68 | std::ios_base::trunc) != 0); 69 assert(f.is_open()); 70 f.sputn(L"abcdefghijklmnopqrstuvwxyz", 26); 71 assert(buf[0] == L'v'); 72 pos_type p = f.pubseekoff(-15, std::ios_base::cur); 73 assert(p == 11); 74 assert(f.sgetc() == L'l'); 75 f.pubseekoff(0, std::ios_base::beg); 76 assert(f.sgetc() == L'a'); 77 f.pubseekoff(-1, std::ios_base::end); 78 assert(f.sgetc() == L'z'); 79 assert(f.pubseekpos(p) == p); 80 assert(f.sgetc() == L'l'); 81 } 82 std::remove("seekoff.dat"); 83 } 84
