问题
I needed a function to get the absolute path and for that purpose I had a look in boost but it only has that in recent version and I'm using an old 1.44. As I cannot update my code on recent boost 1.55 or higher, I decided to re-write that function. It worked fine on Windows but I'm getting in an infinite recursion under Linux and I cannot understand why ? That code is based on the description you can find here
All advice to fix that issue will be welcome ! Thanks
#include "boost/filesystem.hpp"
namespace bfs = boost::filesystem;
inline bfs::path absolute(const bfs::path& p, const bfs::path& base=bfs::current_path())
{
if(p.has_root_directory())
{
if(p.has_root_name()) return p;
else return absolute(base).root_name() / p;
}
else
{
if(p.has_root_name()) return bfs::path(p.root_name()) / bfs::path(absolute(base).root_directory()) / absolute(base).relative_path() / p.relative_path();
else return absolute(base) / p;
}
}
回答1:
Finally I used a copy of the boost v1.55 code to solve that issue.
inline bool is_absolute(const bfs::path p)
{
#if defined(WIN32) || defined(WIN64)
return p.has_root_name() && p.has_root_directory();
#else
return p.has_root_directory();
#endif
}
inline bfs::path absolute(const bfs::path& p, const bfs::path& base=bfs::current_path())
{
// recursively calling absolute is sub-optimal, but is sure and simple
bfs::path abs_base(is_absolute(base) ? base : absolute(base));
// store expensive to compute values that are needed multiple times
bfs::path p_root_name (p.root_name());
bfs::path base_root_name (abs_base.root_name());
bfs::path p_root_directory (p.root_directory());
if (p.empty())
{
return abs_base;
}
if (!p_root_name.empty()) // p.has_root_name()
{
if (p_root_directory.empty()) // !p.has_root_directory()
return p_root_name / abs_base.root_directory()
/ abs_base.relative_path() / p.relative_path();
// p is absolute, so fall through to return p at end of block
}
else if (!p_root_directory.empty()) // p.has_root_directory()
{
return base_root_name / p;
}
else
{
return abs_base / p;
}
return p; // p.is_absolute() is true
}
来源:https://stackoverflow.com/questions/22144256/infinite-recursion-when-i-build-an-absolute-path-using-boost