Rename update action to scan.

src/scan/pathname.cpp

@@ -0,0 +1,220 @@
+/* Copyright 2015, Michele Santullo
+ * This file is part of "dindexer".
+ *
+ * "dindexer" is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * "dindexer" is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with "dindexer".  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "pathname.hpp"
+#include <algorithm>
+#include <functional>
+#include <ciso646>
+#include <iostream>
+
+namespace din {
+	const std::string PathName::m_empty_str("");
+
+	namespace {
+		std::string get_joint_atoms ( const StringPool<char>& parPool, bool parAbs, std::size_t parSkipRight=0 );
+
+		bool ptr_between (const char* parPtr, const char* parBeg, const char* parEnd) {
+			std::less<const char*> less;
+			std::less_equal<const char*> lesseq;
+
+			return lesseq(parBeg, parPtr) and less(parPtr, parEnd);
+		}
+
+		std::size_t count_grouped (boost::string_ref parIn, char parDelim) {
+			std::size_t retval = 0;
+			char prev = '\0';
+			for (auto c : parIn) {
+				retval += (parDelim == c and prev != parDelim ? 1 : 0);
+				prev = c;
+			}
+			return retval;
+		}
+
+		void split_path (std::vector<boost::string_ref>* parOut, boost::string_ref parPath) {
+			auto from = parPath.begin();
+			boost::string_ref::const_iterator next;
+			const auto end = parPath.end();
+			const auto beg = parPath.begin();
+			while (end != (next = std::find(from, end, '/'))) {
+				if (next != from) {
+					parOut->push_back(parPath.substr(from - beg, next - from));
+					from = next;
+				}
+				++from;
+			}
+			if (next != from) {
+				parOut->push_back(parPath.substr(from - beg, next - from));
+			}
+		}
+
+		std::string get_joint_atoms (const StringPool<char>& parPool, bool parAbs, std::size_t parSkipRight) {
+			const auto orig_atom_count = parPool.size();
+			const auto atom_count = (parSkipRight >= orig_atom_count ? 0 : orig_atom_count - parSkipRight);
+			if (not atom_count) {
+				if (parPool.empty() and parAbs) {
+					return std::string("/");
+				}
+				else {
+					return std::string("");
+				}
+			}
+
+			std::size_t reserve = (parAbs ? 1 : 0);
+			for (std::size_t z = 0; z < atom_count; ++z) {
+				reserve += parPool[z].size();
+			}
+			reserve += atom_count - 1;
+
+			std::string out;
+			out.reserve(reserve);
+			const char* slash = (parAbs ? "/" : "");
+			for (std::size_t z = 0; z < atom_count; ++z) {
+				out += slash;
+				const auto& curr_itm = parPool[z];
+				out.insert(out.end(), curr_itm.begin(), curr_itm.end());
+				slash = "/";
+			}
+			return std::move(out);
+		}
+	} //unnamed namespace
+
+	PathName::PathName (boost::string_ref parPath) {
+		if (not parPath.empty()) {
+			m_absolute = ('/' == parPath.front());
+			std::string path(parPath.begin(), parPath.end());
+
+			const auto count = count_grouped(path, '/');
+			const std::size_t trailing = (path.back() == '/' ? 1 : 0);
+			const std::size_t absolute = (m_absolute ? 1 : 0);
+			const auto res = count + 1 - trailing - absolute;
+			std::vector<boost::string_ref> atoms;
+			atoms.reserve(res);
+			split_path(&atoms, path);
+			m_pool.insert(atoms, &path);
+		}
+		else {
+			m_original_path = nullptr;
+			m_absolute = false;
+		}
+	}
+
+	std::string PathName::path() const {
+		return get_joint_atoms(m_pool, m_absolute);
+	}
+
+	void PathName::join (const PathName& parOther) {
+		m_pool.update(parOther.m_pool);
+	}
+
+	const boost::string_ref PathName::operator[] (std::size_t parIndex) const {
+		return *(m_pool.begin() + parIndex);
+	}
+
+	std::size_t PathName::atom_count ( void ) const {
+		return m_pool.size();
+	}
+
+	void PathName::join (const char* parOther) {
+		const std::string src(parOther);
+		const boost::string_ref ref(src);
+		m_pool.insert(ref, &src);
+	}
+
+	void PathName::join (boost::string_ref parOther, const std::string* parSource) {
+		m_pool.insert(parOther, parSource);
+	}
+
+	PathName make_relative_path (const PathName& parBasePath, const PathName& parOtherPath) {
+		if (not parBasePath.is_absolute() and parOtherPath.is_absolute()) {
+			return parOtherPath;
+		}
+
+		std::size_t common_atoms = 0;
+		{
+			const std::size_t shortest = std::min(parOtherPath.atom_count(), parBasePath.atom_count());
+			for (std::size_t z = 0; z < shortest; ++z) {
+				if (parOtherPath[z] == parBasePath[z]) {
+					++common_atoms;
+				}
+				else {
+					break;
+				}
+			}
+		}
+
+		PathName retval("");
+		const auto ellipses_count = parBasePath.atom_count() - common_atoms;
+		for (std::size_t z = 0; z < ellipses_count; ++z) {
+			retval.join("..");
+		}
+
+		const auto remaining_atoms = parOtherPath.atom_count() - common_atoms;
+		for (std::size_t z = 0; z < remaining_atoms; ++z) {
+			retval.join(parOtherPath[z + common_atoms], parOtherPath.get_stringref_source(z + common_atoms));
+		}
+		return std::move(retval);
+	}
+
+	const std::string* PathName::get_stringref_source (std::size_t parIndex) const {
+		return m_pool.get_stringref_source(parIndex);
+	}
+
+	std::string PathName::dirname() const {
+		if (this->atom_count() == 0)
+			return std::string();
+
+		return get_joint_atoms(m_pool, m_absolute, 1);
+	}
+
+	std::ostream& operator<< (std::ostream& parStream, const PathName& parPath) {
+		parStream << parPath.path();
+		return parStream;
+	}
+
+	PathName& PathName::pop_right() {
+		m_pool.pop();
+		return *this;
+	}
+
+	bool PathName::operator!= (const PathName& parOther) const {
+		const auto count = atom_count();
+		if (count != parOther.atom_count()) {
+			return true;
+		}
+
+		for (std::size_t z = 0; z < count; ++z) {
+			if ((*this)[z] != parOther[z]) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	bool PathName::operator== (const PathName& parOther) const {
+		const auto count = atom_count();
+		if (count != parOther.atom_count()) {
+			return false;
+		}
+
+		for (std::size_t z = 0; z < count; ++z) {
+			if ((*this)[z] != parOther[z]) {
+				return false;
+			}
+		}
+		return true;
+	}
+} //namespace din