process/include/boost/process/error.hpp
2016-12-04 03:57:30 +01:00

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6.5 KiB
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// Copyright (c) 2006, 2007 Julio M. Merino Vidal
// Copyright (c) 2008 Ilya Sokolov, Boris Schaeling
// Copyright (c) 2009 Boris Schaeling
// Copyright (c) 2010 Felipe Tanus, Boris Schaeling
// Copyright (c) 2011, 2012 Jeff Flinn, Boris Schaeling
// Copyright (c) 2016 Klemens D. Morgenstern
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_PROCESS_DETAIL_ERROR_HPP
#define BOOST_PROCESS_DETAIL_ERROR_HPP
#include <boost/process/detail/config.hpp>
#include <boost/process/detail/traits.hpp>
#if defined(BOOST_POSIX_API)
#include <boost/process/detail/posix/handler.hpp>
#elif defined(BOOST_WINDOWS_API)
#include <boost/process/detail/windows/handler.hpp>
#endif
#include <system_error>
#include <type_traits>
#include <boost/fusion/algorithm/query/find_if.hpp>
#include <boost/fusion/sequence/intrinsic/begin.hpp>
#include <boost/fusion/sequence/intrinsic/end.hpp>
#include <boost/fusion/container/vector/convert.hpp>
#include <boost/fusion/iterator/deref.hpp>
#include <boost/fusion/sequence/comparison/equal_to.hpp>
#include <boost/fusion/container/set/convert.hpp>
#include <boost/type_index.hpp>
/** \file boost/process/error.hpp
*
* Header which provides the error properties. It allows to explicitly set the error handling, the properties are:
*
\xmlonly
<programlisting>
namespace boost {
namespace process {
<emphasis>unspecified</emphasis> <globalname alt="boost::process::ignore_error">ignore_error</globalname>;
<emphasis>unspecified</emphasis> <globalname alt="boost::process::throw_on_error">throw_on_error</globalname>;
<emphasis>unspecified</emphasis> <globalname alt="boost::process::error">error</globalname>;
<emphasis>unspecified</emphasis> <globalname alt="boost::process::error_ref">error_ref</globalname>;
<emphasis>unspecified</emphasis> <globalname alt="boost::process::error_code">error_code</globalname>;
}
}
</programlisting>
\endxmlonly
* For error there are two aliases: error_ref and error_code
*/
namespace boost { namespace process {
namespace detail {
struct throw_on_error_ : ::boost::process::detail::api::handler_base_ext
{
constexpr throw_on_error_() {};
template <class Executor>
void on_error(Executor&, const std::error_code & ec) const
{
throw process_error(ec, "process creation failed");
}
const throw_on_error_ &operator()() const {return *this;}
};
struct ignore_error_ : ::boost::process::detail::api::handler_base_ext
{
constexpr ignore_error_() {};
};
struct set_on_error : ::boost::process::detail::api::handler_base_ext
{
set_on_error(const set_on_error&) = default;
explicit set_on_error(std::error_code &ec) : ec_(ec) {}
template <class Executor>
void on_error(Executor&, const std::error_code & ec) const
{
ec_ = ec;
}
private:
std::error_code &ec_;
};
struct error_
{
constexpr error_() {}
set_on_error operator()(std::error_code &ec) const {return set_on_error(ec);}
set_on_error operator= (std::error_code &ec) const {return set_on_error(ec);}
};
template<typename T>
struct is_error_handler : std::false_type {};
template<> struct is_error_handler<set_on_error> : std::true_type {};
template<> struct is_error_handler<throw_on_error_> : std::true_type {};
template<> struct is_error_handler<ignore_error_> : std::true_type {};
template<typename Iterator, typename End>
struct has_error_handler_impl
{
typedef typename boost::fusion::result_of::deref<Iterator>::type ref_type;
typedef typename std::remove_reference<ref_type>::type res_type_;
typedef typename std::remove_cv<res_type_>::type res_type;
typedef typename is_error_handler<res_type>::type cond;
typedef typename boost::fusion::result_of::next<Iterator>::type next_itr;
typedef typename has_error_handler_impl<next_itr, End>::type next;
typedef typename boost::mpl::or_<cond, next>::type type;
};
template<typename Iterator>
struct has_error_handler_impl<Iterator, Iterator>
{
typedef boost::mpl::false_ type;
};
template<typename Sequence>
struct has_error_handler
{
typedef typename boost::fusion::result_of::as_vector<Sequence>::type vector_type;
typedef typename has_error_handler_impl<
typename boost::fusion::result_of::begin<vector_type>::type,
typename boost::fusion::result_of::end< vector_type>::type
>::type type;
};
template<typename Sequence>
struct has_ignore_error
{
typedef typename boost::fusion::result_of::as_set<Sequence>::type set_type;
typedef typename boost::fusion::result_of::has_key<set_type, ignore_error_>::type type1;
typedef typename boost::fusion::result_of::has_key<set_type, ignore_error_&>::type type2;
typedef typename boost::fusion::result_of::has_key<set_type, const ignore_error_&>::type type3;
typedef typename boost::mpl::or_<type1,type2, type3>::type type;
};
struct error_builder
{
std::error_code *err;
typedef set_on_error result_type;
set_on_error get_initializer() {return set_on_error(*err);};
void operator()(std::error_code & ec) {err = &ec;};
};
template<>
struct initializer_tag<std::error_code>
{
typedef error_tag type;
};
template<>
struct initializer_builder<error_tag>
{
typedef error_builder type;
};
}
/**The ignore_error property will disable any error handling. This can be useful
on linux, where error handling will require a pipe.*/
constexpr boost::process::detail::ignore_error_ ignore_error;
/**The throw_on_error property will enable the exception when launching a process.
It is unnecessary by default, but may be used, when an additional error_code is provided.*/
constexpr boost::process::detail::throw_on_error_ throw_on_error;
/**
The error property will set the executor to handle any errors by setting an
[std::error_code](http://en.cppreference.com/w/cpp/error/error_code).
\code{.cpp}
std::error_code ec;
system("gcc", error(ec));
\endcode
The following syntax is valid:
\code{.cpp}
error(ec);
error=ec;
\endcode
The overload version is achieved by just passing an object of
[std::error_code](http://en.cppreference.com/w/cpp/error/error_code) to the function.
*/
constexpr boost::process::detail::error_ error;
///Alias for \xmlonly <globalname alt="boost::process::error">error</globalname> \endxmlonly .
constexpr boost::process::detail::error_ error_ref;
///Alias for \xmlonly <globalname alt="boost::process::error">error</globalname> \endxmlonly .
constexpr boost::process::detail::error_ error_code;
}}
#endif