ceph/src/boost/libs/context/src/posix/stack_traits.cpp

   1
   2 //          Copyright Oliver Kowalke 2014.
   3 // Distributed under the Boost Software License, Version 1.0.
   4 //    (See accompanying file LICENSE_1_0.txt or copy at
   5 //          http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #include "boost/context/stack_traits.hpp"
   8
   9 extern "C" {
  10 #include <signal.h>
  11 #include <sys/resource.h>
  12 #include <sys/time.h>
  13 #include <unistd.h>
  14 }
  15
  16 //#if _POSIX_C_SOURCE >= 200112L
  17
  18 #include <algorithm>
  19 #include <cmath>
  20
  21 #include <boost/assert.hpp>
  22 #include <boost/config.hpp>
  23 #if defined(BOOST_NO_CXX11_HDR_MUTEX)
  24 # include <boost/thread.hpp>
  25 #else
  26 # include <mutex>
  27 #endif
  28
  29 #if !defined (SIGSTKSZ)
  30 # define SIGSTKSZ (8 * 1024)
  31 # define UDEF_SIGSTKSZ
  32 #endif
  33
  34 #ifdef BOOST_HAS_ABI_HEADERS
  35 #  include BOOST_ABI_PREFIX
  36 #endif
  37
  38 namespace {
  39
  40 void pagesize_( std::size_t * size) BOOST_NOEXCEPT_OR_NOTHROW {
  41     // conform to POSIX.1-2001
  42     * size = ::sysconf( _SC_PAGESIZE);
  43 }
  44
  45 void stacksize_limit_( rlimit * limit) BOOST_NOEXCEPT_OR_NOTHROW {
  46     // conforming to POSIX.1-2001
  47     ::getrlimit( RLIMIT_STACK, limit);
  48 }
  49
  50 std::size_t pagesize() BOOST_NOEXCEPT_OR_NOTHROW {
  51     static std::size_t size = 0;
  52 #if defined(BOOST_NO_CXX11_HDR_MUTEX)
  53     static boost::once_flag flag = BOOST_ONCE_INIT;
  54     boost::call_once( flag, pagesize_, & size);
  55 #else
  56     static std::once_flag flag;
  57     std::call_once( flag, pagesize_, & size);
  58 #endif
  59     return size;
  60 }
  61
  62 rlimit stacksize_limit() BOOST_NOEXCEPT_OR_NOTHROW {
  63     static rlimit limit;
  64 #if defined(BOOST_NO_CXX11_HDR_MUTEX)
  65     static boost::once_flag flag = BOOST_ONCE_INIT;
  66     boost::call_once( flag, stacksize_limit_, & limit);
  67 #else
  68     static std::once_flag flag;
  69     std::call_once( flag, stacksize_limit_, & limit);
  70 #endif
  71     return limit;
  72 }
  73
  74 }
  75
  76 namespace boost {
  77 namespace context {
  78
  79 bool
  80 stack_traits::is_unbounded() BOOST_NOEXCEPT_OR_NOTHROW {
  81     return RLIM_INFINITY == stacksize_limit().rlim_max;
  82 }
  83
  84 std::size_t
  85 stack_traits::page_size() BOOST_NOEXCEPT_OR_NOTHROW {
  86     return pagesize();
  87 }
  88
  89 std::size_t
  90 stack_traits::default_size() BOOST_NOEXCEPT_OR_NOTHROW {
  91     std::size_t size = 8 * minimum_size();
  92     if ( is_unbounded() ) {
  93         return size;
  94     }
  95
  96     BOOST_ASSERT( maximum_size() >= minimum_size() );
  97     return maximum_size() == size
  98         ? size
  99         : (std::min)( size, maximum_size() );
 100 }
 101
 102 std::size_t
 103 stack_traits::minimum_size() BOOST_NOEXCEPT_OR_NOTHROW {
 104     return SIGSTKSZ;
 105 }
 106
 107 std::size_t
 108 stack_traits::maximum_size() BOOST_NOEXCEPT_OR_NOTHROW {
 109     BOOST_ASSERT( ! is_unbounded() );
 110     return static_cast< std::size_t >( stacksize_limit().rlim_max);
 111 }
 112
 113 }}
 114
 115 #ifdef BOOST_HAS_ABI_HEADERS
 116 #  include BOOST_ABI_SUFFIX
 117 #endif
 118
 119 #ifdef UDEF_SIGSTKSZ
 120 # undef SIGSTKSZ
 121 #endif