libcruft-util/exe_linux.cpp
Danny Robson 34788756d2 build: don't use './' as an include prefix
GCC produces ODR error when including paths of the form './foo' and
'foo' in the same binary. Rather than managing duplication we just
universally pick the absolute form over the relative form.
2017-11-22 16:49:37 +11:00

52 lines
1.5 KiB
C++

/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Copyright 2010-2016 Danny Robson <danny@nerdcruft.net>
*/
#include "exe.hpp"
#include "except.hpp"
#include "cast.hpp"
#include <vector>
#include <experimental/filesystem>
#include <unistd.h>
///////////////////////////////////////////////////////////////////////////////
std::experimental::filesystem::path
util::image_path (void)
{
static const char PROC_SELF[] = "/proc/self/exe";
// We can't use lstat to check the size of the link in proc, as Linux
// will return 0 for most entries under proc. Instead we've got to
// iterate for a correct size.
std::vector<char> resolved (256);
retry:
const auto written = readlink (PROC_SELF, resolved.data (), resolved.size ());
if (written < 0)
errno_error::throw_code ();
if (sign_cast<size_t> (written) == resolved.size ()) {
resolved.resize (resolved.size () * 2);
goto retry;
}
return std::experimental::filesystem::path (resolved.data (), resolved.data () + written);
}