Aegisub/libaegisub/common/path.cpp
2014-05-23 07:28:24 -07:00

146 lines
4.2 KiB
C++

// Copyright (c) 2013, Thomas Goyne <plorkyeran@aegisub.org>
//
// Permission to use, copy, modify, and distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
//
// Aegisub Project http://www.aegisub.org/
/// @file path.cpp
/// @brief Platform-independent path code
/// @ingroup libaegisub
#include "libaegisub/path.h"
#include "libaegisub/fs.h"
#include <boost/algorithm/string/predicate.hpp>
#include <boost/range/distance.hpp>
namespace {
template<class T, class U>
typename T::const_iterator last_less_than(T const& cont, U const& value) {
auto it = cont.upper_bound(value);
if (it != cont.begin())
--it;
return it;
}
}
namespace agi {
Path::Path() {
tokens["?user"];
tokens["?local"];
tokens["?data"];
tokens["?temp"];
tokens["?dictionary"];
tokens["?docs"];
FillPlatformSpecificPaths();
tokens["?audio"];
tokens["?script"];
tokens["?video"];
}
fs::path Path::Decode(std::string const& path) const {
const auto it = last_less_than(tokens, path);
if (!it->second.empty() && boost::starts_with(path, it->first))
return (it->second/path.substr(it->first.size())).make_preferred();
return fs::path(path).make_preferred();
}
fs::path Path::MakeRelative(fs::path const& path, std::string const& token) const {
const auto it = tokens.find(token);
if (it == tokens.end()) throw agi::InternalError("Bad token: " + token, nullptr);
return MakeRelative(path, it->second);
}
fs::path Path::MakeRelative(fs::path const& path, fs::path const& base) const {
if (path.empty() || base.empty()) return path;
const auto str = path.string();
if (boost::starts_with(str, "?dummy") || boost::starts_with(str, "dummy-audio:"))
return path;
// Paths on different volumes can't be made relative to each other
if (path.has_root_name() && path.root_name() != base.root_name())
return path.string();
auto path_it = path.begin();
auto ref_it = base.begin();
for (; path_it != path.end() && ref_it != base.end() && *path_it == *ref_it; ++path_it, ++ref_it) ;
agi::fs::path result;
for (; ref_it != base.end(); ++ref_it)
result /= "..";
for (; path_it != path.end(); ++path_it)
result /= *path_it;
return result;
}
fs::path Path::MakeAbsolute(fs::path path, std::string const& token) const {
const auto it = tokens.find(token);
if (it == tokens.end()) throw agi::InternalError("Bad token: " + token, nullptr);
if (path.empty()) return path;
path.make_preferred();
const auto str = path.string();
if (boost::starts_with(str, "?dummy") || boost::starts_with(str, "dummy-audio:"))
return path;
return (it->second.empty() || path.is_absolute()) ? path : it->second/path;
}
std::string Path::Encode(fs::path const& path) const {
// Find the shortest encoding of path made relative to each token
std::string shortest = path.string();
size_t length = boost::distance(path);
for (auto const& tok : tokens) {
if (tok.second.empty()) continue;
const auto p = MakeRelative(path, tok.first);
const size_t d = boost::distance(p);
if (d < length) {
length = d;
shortest = (tok.first/p).string();
}
}
return shortest;
}
void Path::SetToken(std::string const& token_name, fs::path const& token_value) {
const auto it = tokens.find(token_name);
if (it == tokens.end()) throw agi::InternalError("Bad token: " + token_name, nullptr);
if (token_value.empty())
it->second = token_value;
else if (!token_value.is_absolute())
it->second.clear();
else {
it->second = token_value;
it->second.make_preferred();
if (fs::FileExists(it->second))
it->second = it->second.parent_path();
}
paths.clear();
for (auto const& tok : tokens) {
if (!tok.second.empty())
paths[tok.second] = tok.first;
}
}
}