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

   1 // 2001-05-21 Benjamin Kosnik  <bkoz@redhat.com>
   2
   3 // Copyright (C) 2001-2024 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
  38 // Test overloaded virtual functions.
  39 void test05()
  40 {
  41   using namespace std;
  42   using namespace __gnu_test;
  43   typedef filebuf::int_type     int_type;
  44   typedef filebuf::traits_type  traits_type;
  45
  46   streamsize                    strmsz_1, strmsz_2;
  47   char carray1[13] = "";
  48   char carray2[8192] = "";
  49   char buffer[8192] = "";
  50   int_type                      c1, c4;
  51
  52   // streamsize sgetn(char_type *s, streamsize n)
  53   // streamsize xsgetn(char_type *s, streamsize n)
  54   // assign up to n chars to s from input sequence, indexing in_cur as
  55   // approp and returning the number of chars assigned
  56
  57   // in
  58   {
  59     constraint_filebuf fb_01;
  60     // Need this since BUFSIZ is only guaranteed >= 255 and we want
  61     // to trigger the same underflow situation everywhere.
  62     fb_01.pubsetbuf(buffer, 8192);
  63     fb_01.open(name_01, ios_base::in);
  64     VERIFY( !fb_01.write_position() );
  65     strmsz_1 = fb_01.in_avail(); // 8261
  66     strmsz_2 = fb_01.sgetn(carray1, 10);
  67     VERIFY( strmsz_2 == 10 );
  68     strmsz_2 = fb_01.in_avail();
  69     VERIFY( strmsz_1 > strmsz_2 );
  70     c1 = fb_01.sgetc();
  71     VERIFY( c1 == 'b' );
  72     strmsz_1 = fb_01.in_avail();
  73     strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
  74     VERIFY( strmsz_1 == strmsz_2 - 5 );
  75     c4 = fb_01.sgetc(); // buffer should have underflowed from above.
  76     VERIFY( c4 == 'e' );
  77     strmsz_1 = fb_01.in_avail();
  78     VERIFY( strmsz_1 > 0 );
  79     strmsz_2 = fb_01.sgetn(carray2, strmsz_1 + 5);
  80     VERIFY( strmsz_1 == strmsz_2 ); //at the end of the actual file
  81     VERIFY( !fb_01.write_position() );
  82     VERIFY( !fb_01.read_position() );
  83   }
  84 }
  85
  86 int main()
  87 {
  88   test05();
  89   return 0;
  90 }