ceph/src/boost/libs/iostreams/test/write_failure_test.cpp

   1 // (C) COPYRIGHT 2017 ARM Limited
   2
   3 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
   5
   6 #include <boost/iostreams/categories.hpp>  // tags.
   7 #include <boost/iostreams/detail/adapter/non_blocking_adapter.hpp>
   8 #include <boost/iostreams/filter/gzip.hpp>
   9 #include <boost/iostreams/filtering_stream.hpp>
  10 #include <boost/iostreams/write.hpp>
  11 #include <boost/test/unit_test.hpp>
  12
  13 using namespace boost;
  14 using namespace boost::iostreams;
  15 using boost::unit_test::test_suite;
  16
  17 struct limit_device {
  18     typedef char char_type;
  19     typedef sink_tag category;
  20     int written, overflow_count, limit;
  21     explicit limit_device(int limit = 20) : written(0), overflow_count(0), limit(limit) {}
  22     std::streamsize write(const char_type *, std::streamsize n)
  23     {
  24         if (written > limit) {
  25             // first return partial writes, then an error
  26             ++overflow_count;
  27             if (overflow_count > 2 || n < 2)
  28             {
  29                 return -1;
  30             }
  31             n /= 2;
  32         }
  33         written += n;
  34         return n;
  35     }
  36 };
  37
  38 static void disk_full_test()
  39 {
  40     // non_blocking_adapter used to handle write returning
  41     // -1 correctly, usually hanging (see ticket 2557).
  42     // As non_blocking_adapter is used for ofstream, this
  43     // would happen for ordinary files when reaching quota,
  44     // disk full or rlimits.
  45     // Could be tested without gzip_compressor,
  46     // but this tests a bit better that the whole path can handle it.
  47     // TODO: should there be some check on error bit being set
  48     // or should an exception be triggered?
  49     limit_device outdev;
  50     non_blocking_adapter<limit_device> nonblock_outdev(outdev);
  51     filtering_ostream out;
  52     out.push(gzip_compressor());
  53     out.push(nonblock_outdev);
  54     write(out, "teststring0123456789", 20);
  55     out.flush();
  56     write(out, "secondwrite123456789", 20);
  57     close(out);
  58 }
  59
  60 test_suite* init_unit_test_suite(int, char* [])
  61 {
  62     test_suite* test = BOOST_TEST_SUITE("disk full test");
  63     test->add(BOOST_TEST_CASE(&disk_full_test));
  64     return test;
  65 }