diff options
| author | Jonathan Wakely <jwakely@redhat.com> | 2015-09-17 16:06:42 +0100 |
|---|---|---|
| committer | Jonathan Wakely <redi@gcc.gnu.org> | 2015-09-17 16:06:42 +0100 |
| commit | a2b4d73daf5854c40b71e0b655a9507bf6977279 (patch) | |
| tree | 0dd3c7308998c3b62b6757ec7e3b42426e1828b6 /libstdc++-v3 | |
| parent | 2eb57e545ba21b1776371acf6cb11bc28233bd82 (diff) | |
| download | gcc-a2b4d73daf5854c40b71e0b655a9507bf6977279.zip gcc-a2b4d73daf5854c40b71e0b655a9507bf6977279.tar.gz gcc-a2b4d73daf5854c40b71e0b655a9507bf6977279.tar.bz2 | |
Make std::random_device retry after short reads
PR libstdc++/65142
* src/c++11/random.cc (random_device::_M_getval()): Retry after short
reads.
From-SVN: r227872
Diffstat (limited to 'libstdc++-v3')
| -rw-r--r-- | libstdc++-v3/ChangeLog | 4 | ||||
| -rw-r--r-- | libstdc++-v3/src/c++11/random.cc | 24 |
2 files changed, 21 insertions, 7 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index c70ad43..25aa16b 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,5 +1,9 @@ 2015-09-17 Jonathan Wakely <jwakely@redhat.com> + PR libstdc++/65142 + * src/c++11/random.cc (random_device::_M_getval()): Retry after short + reads. + * include/std/system_error (error_code::operator bool(), error_condition::operator bool()): Remove redundant conditional expression. diff --git a/libstdc++-v3/src/c++11/random.cc b/libstdc++-v3/src/c++11/random.cc index 1d102c7..f1d6125 100644 --- a/libstdc++-v3/src/c++11/random.cc +++ b/libstdc++-v3/src/c++11/random.cc @@ -130,16 +130,26 @@ namespace std _GLIBCXX_VISIBILITY(default) #endif result_type __ret; - + void* p = &__ret; + size_t n = sizeof(result_type); #ifdef _GLIBCXX_HAVE_UNISTD_H - auto e = read(fileno(static_cast<FILE*>(_M_file)), - static_cast<void*>(&__ret), sizeof(result_type)); + do + { + const int e = read(fileno(static_cast<FILE*>(_M_file)), p, n); + if (e > 0) + { + n -= e; + p = static_cast<char*>(p) + e; + } + else if (e != -1 || errno != EINTR) + __throw_runtime_error(__N("random_device could not be read")); + } + while (n > 0); #else - auto e = std::fread(static_cast<void*>(&__ret), sizeof(result_type), - 1, static_cast<FILE*>(_M_file)); + const size_t e = std::fread(p, n, 1, static_cast<FILE*>(_M_file)); + if (e != 1) + __throw_runtime_error(__N("random_device could not be read")); #endif - if (e != sizeof(result_type)) - __throw_runtime_error(__N("random_device could not read enough bytes")); return __ret; } |