libstdc++-v3/testsuite/27_io/basic_filebuf/sgetn/char/1-io.cc

   1 // 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
   2
   3 // Copyright (C) 2001-2019 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 // The ARM simulator does not provide support for "fstat", which
  21 // causes "in_avail" to return an incorrect value.
  22 // { dg-do run { xfail arm*-*-elf arm*-*-eabi } }
  23
  24 // 27.8.1.4 Overridden virtual functions
  25
  26 // { dg-require-fileio "" }
  27 // { dg-require-binary-io "" }
  28
  29 #include <fstream>
  30 #include <testsuite_hooks.h>
  31 #include <testsuite_io.h>
  32
  33 // @require@ %-*.tst %-*.txt
  34 // @diff@ %-*.tst %*.txt
  35
  36 const char name_01[] = "sgetn.txt"; // file with data in it
  37 const char name_03[] = "tmp_sgetn_1io.tst"; // empty file, need to create
  38
  39 // Test overloaded virtual functions.
  40 void test05()
  41 {
  42   using namespace std;
  43   using namespace __gnu_test;
  44   typedef filebuf::int_type     int_type;
  45   typedef filebuf::traits_type  traits_type;
  46
  47   streamsize                    strmsz_1, strmsz_2;
  48   char carray1[13] = "";
  49   char carray2[8192] = "";
  50   char buffer[8192] = "";
  51   int_type                      c1, c4;
  52
  53   // streamsize sgetn(char_type *s, streamsize n)
  54   // streamsize xsgetn(char_type *s, streamsize n)
  55   // assign up to n chars to s from input sequence, indexing in_cur as
  56   // approp and returning the number of chars assigned
  57
  58   // in | out 1
  59   {
  60     constraint_filebuf fb_03;
  61     fb_03.open(name_03, ios_base::out | ios_base::in | ios_base::trunc);
  62     VERIFY( !fb_03.write_position() );
  63     VERIFY( !fb_03.read_position() );
  64     strmsz_1 = fb_03.sgetn(carray1, 10);
  65     VERIFY( strmsz_1 == 0 );
  66     VERIFY( !fb_03.write_position() );
  67     VERIFY( !fb_03.read_position() );
  68   }
  69
  70   // in | out 2
  71   {
  72     constraint_filebuf fb_01;
  73     // Need this since BUFSIZ is only guaranteed >= 255 and we want
  74     // to trigger the same underflow situation everywhere.
  75     fb_01.pubsetbuf(buffer, 8192);
  76     fb_01.open(name_01, ios_base::in | ios_base::out);
  77     VERIFY( !fb_01.write_position() );
  78     strmsz_1 = fb_01.in_avail();
  79     strmsz_2 = fb_01.sgetn(carray1, 10);
  80     VERIFY( strmsz_2 == 10 );
  81     strmsz_2 = fb_01.in_avail();
  82     VERIFY( strmsz_1 > strmsz_2 );
  83     c1 = fb_01.sgetc();
  84     VERIFY( c1 == 'b' );
  85     strmsz_1 = fb_01.in_avail();
  86     strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
  87     VERIFY( strmsz_1 == strmsz_2 - 5 );
  88     c4 = fb_01.sgetc(); // buffer should have underflowed from above.
  89     VERIFY( c4 == 'e' );
  90     strmsz_1 = fb_01.in_avail();
  91     VERIFY( strmsz_1 > 0 );
  92     strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
  93     VERIFY( strmsz_1 == strmsz_2 ); //at the end of the actual file
  94     VERIFY( !fb_01.write_position() );
  95     VERIFY( !fb_01.read_position() );
  96   }
  97 }
  98
  99 int main()
 100 {
 101   test05();
 102   return 0;
 103 }