More generic implementation for searching nodes

src/main.cpp

@@ -1,4 +1,6 @@
 #include "parser.hpp"
+#include "split.hpp"
+
 #include <iostream>
 #include <fstream>
 #include <string>
@@ -13,8 +15,6 @@
 #include <sha1/FileSource.hpp>
 
 namespace {
-constexpr char g_test[] = "d8:announce75:http://tracker.bakabt.me:2710/f53895da71a9546b3b14682e63cb9069/announce.php7:comment21:http://www.bakabt.me/10:created by37:ruTorrent (PHP Class - Adrien Gibrat)13:creation datei1394860194ee";
-
 std::string load_file (const std::string& path) {
 	std::ifstream ifs(path);
 	ifs >> std::noskipws;
@@ -107,13 +107,35 @@ struct PrintVisitor {
 	bool skip_first;
 };
 
-struct FindHashesVisitor : boost::static_visitor<std::string_view> {
+struct FindStringVisitor : boost::static_visitor<std::string_view> {
+	FindStringVisitor (std::string path) {
+		auto split = dincore::split(path, '/', true, true);
+		search.reserve(split.size());
+		for (const auto& itm : split) {
+			search.emplace_back(itm.data(), itm.size());
+		}
+	}
+
+	bool is_prefix_path (std::string_view curr_element) const {
+		if (path.size() + 1 > search.size())
+			return false;
+
+		return std::equal(path.cbegin(), path.cend(), search.cbegin()) and (search[path.size()] == curr_element);
+	}
+
+	bool is_path_found() const {
+		if (path.size() != search.size())
+			return false;
+
+		return std::equal(path.cbegin(), path.cend(), search.cbegin());
+	}
+
 	std::string_view operator() (long long value) {
 		return {};
 	}
 
 	std::string_view operator() (const duck::TorrentStringType& value) {
-		if (this_is_pieces)
+		if (is_path_found())
 			return value;
 		else
 			return {};
@@ -124,22 +146,20 @@ struct FindHashesVisitor : boost::static_visitor<std::string_view> {
 	}
 
 	std::string_view operator() (const std::map<duck::TorrentStringType, duck::TorrentValue>& value) {
-		if (this_is_pieces)
+		if (is_path_found())
 			return {};
 
 		for (const auto& item : value) {
-			if (item.first == "info") {
-				return boost::apply_visitor(*this, item.second);
-			}
-			else if (item.first == "pieces") {
-				this_is_pieces = true;
+			if (is_prefix_path(item.first)) {
+				path.push_back(item.first);
 				return boost::apply_visitor(*this, item.second);
 			}
 		}
 		return {};
 	}
 
-	bool this_is_pieces{false};
+	std::vector<std::string_view> path;
+	std::vector<std::string> search;
 };
 
 std::vector<std::array<std::uint32_t, 5>> collect_hashes (std::string_view hashes) {
@@ -189,7 +209,7 @@ int main(int argc, const char* argv[]) {
 	}
 
 	if (values.size() == 1) {
-		FindHashesVisitor visitor;
+		FindStringVisitor visitor("/info/pieces");
 		auto source_hashes = boost::apply_visitor(visitor, values.front());
 		std::cout << "Got source_hashes with size " << source_hashes.size() << '\n';
 		auto hashes = collect_hashes(source_hashes);

src/meson.build

@@ -1,6 +1,7 @@
 executable(meson.project_name(),
   'main.cpp',
   'parser.cpp',
+  'split.cpp',
   dependencies: [
 	boost_dep,
     libstriezel_dep,

src/split.cpp

@@ -0,0 +1,72 @@
+/* Copyright 2015, 2016, 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 "split.hpp"
+#include <boost/algorithm/string/finder.hpp>
+#include <boost/algorithm/string/split.hpp>
+#include <boost/algorithm/string/trim.hpp>
+#include <boost/range/adaptor/transformed.hpp>
+#include <boost/range/adaptor/filtered.hpp>
+#include <ciso646>
+
+namespace dincore {
+	std::vector<std::string_view> split (std::string_view parList, char parSeparator, bool parTrim, bool parDeleteEmpty) {
+		using OutRange = boost::iterator_range<std::string::const_iterator>;
+		using boost::token_finder;
+		using boost::adaptors::transformed;
+		using boost::adaptors::filtered;
+		using std::string_view;
+		using boost::iter_split;
+		using boost::trim_copy;
+
+		std::vector<OutRange> out_range;
+
+		//See:
+		//https://stackoverflow.com/questions/27999941/how-to-use-boostsplit-with-booststring-ref-in-boost-1-55
+		//http://www.boost.org/doc/libs/1_60_0/doc/html/boost/algorithm/iter_split.html
+		//http://www.boost.org/doc/libs/1_60_0/doc/html/boost/algorithm/token_finder.html
+		//https://stackoverflow.com/questions/20781090/difference-between-boostsplit-vs-boostiter-split
+		if (parTrim and parDeleteEmpty) {
+			return boost::copy_range<std::vector<string_view>>(
+				iter_split(out_range, parList, token_finder([parSeparator](char c){return parSeparator==c;})) |
+					transformed([](const OutRange& r){return trim_copy(r);}) |
+					transformed([](const OutRange& r){return string_view(&*r.begin(), r.size());}) |
+					filtered([](string_view r){return not r.empty();})
+			);
+		}
+		else if (parTrim) {
+			return boost::copy_range<std::vector<string_view>>(
+				iter_split(out_range, parList, token_finder([parSeparator](char c){return parSeparator==c;})) |
+					transformed([](const OutRange& r){return trim_copy(r);}) |
+					transformed([](const OutRange& r){return string_view(&*r.begin(), r.size());})
+			);
+		}
+		else if (parDeleteEmpty) {
+			return boost::copy_range<std::vector<string_view>>(
+				iter_split(out_range, parList, token_finder([parSeparator](char c){return parSeparator==c;})) |
+					transformed([](const OutRange& r){return string_view(&*r.begin(), r.size());}) |
+					filtered([](string_view r){return not r.empty();})
+			);
+		}
+		else {
+			return boost::copy_range<std::vector<string_view>>(
+				iter_split(out_range, parList, token_finder([parSeparator](char c){return parSeparator==c;})) |
+					transformed([](const OutRange& r){return string_view(&*r.begin(), r.size());})
+			);
+		}
+	}
+} //namespace dincore

src/split.hpp

@@ -0,0 +1,28 @@
+/* Copyright 2015, 2016, 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/>.
+ */
+
+#ifndef id913CE9D2F60745349F39F2C82455973E
+#define id913CE9D2F60745349F39F2C82455973E
+
+#include <vector>
+#include <string_view>
+
+namespace dincore {
+	std::vector<std::string_view> split ( std::string_view parList, char parSeparator, bool parTrim, bool parDeleteEmpty );
+} //namespace dincore
+
+#endif