use UNC paths pervasively on windows

CMakeLists.txt

@@ -234,7 +234,6 @@ set(libtorrent_aux_include_files
 	ip_notifier
 	listen_socket_handle
 	lsd
-	max_path
 	merkle
 	noexcept_movable
 	numeric_cast

examples/make_torrent.cpp

@@ -36,7 +36,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/storage.hpp"
 #include "libtorrent/hasher.hpp"
 #include "libtorrent/create_torrent.hpp"
-#include "libtorrent/aux_/max_path.hpp" // for TORRENT_MAX_PATH
 
 #include <functional>
 #include <cstdio>
@@ -259,17 +258,24 @@ int main(int argc_, char const* argv_[]) try
 	if (full_path[0] != '/')
 #endif
 	{
-		char cwd[TORRENT_MAX_PATH];
+		char cwd[2048];
 #ifdef TORRENT_WINDOWS
-		_getcwd(cwd, sizeof(cwd));
+#define getcwd_ _getcwd
-		full_path = cwd + ("\\" + full_path);
 #else
-		char const* ret = getcwd(cwd, sizeof(cwd));
+#define getcwd_ getcwd
+#endif
+
+		char const* ret = getcwd_(cwd, sizeof(cwd));
 		if (ret == nullptr) {
 			std::cerr << "failed to get current working directory: "
 				<< strerror(errno) << "\n";
 			return 1;
 		}
+
+#undef getcwd_
+#ifdef TORRENT_WINDOWS
+		full_path = cwd + ("\\" + full_path);
+#else
 		full_path = cwd + ("/" + full_path);
 #endif
 	}

include/libtorrent/Makefile.am

@@ -178,7 +178,6 @@ nobase_include_HEADERS = \
   aux_/generate_peer_id.hpp         \
   aux_/io.hpp                       \
   aux_/listen_socket_handle.hpp     \
-  aux_/max_path.hpp                 \
   aux_/path.hpp                     \
   aux_/merkle.hpp                   \
   aux_/session_call.hpp             \

include/libtorrent/aux_/escape_string.hpp

@@ -64,7 +64,8 @@ namespace libtorrent {
 	TORRENT_EXTRA_EXPORT std::string maybe_url_encode(std::string const& url);
 
 	TORRENT_EXTRA_EXPORT string_view trim(string_view);
-	TORRENT_EXTRA_EXPORT string_view::size_type find(string_view haystack, string_view needle, string_view::size_type pos);
+	TORRENT_EXTRA_EXPORT string_view::size_type find(string_view haystack
+		, string_view needle, string_view::size_type pos);
 
 #if TORRENT_ABI_VERSION == 1
 	// deprecated in 1.2

include/libtorrent/aux_/max_path.hpp

@@ -1,67 +0,0 @@
-/*
-
-Copyright (c) 2016, Arvid Norberg
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-
-    * Redistributions of source code must retain the above copyright
-      notice, this list of conditions and the following disclaimer.
-    * Redistributions in binary form must reproduce the above copyright
-      notice, this list of conditions and the following disclaimer in
-      the documentation and/or other materials provided with the distribution.
-    * Neither the name of the author nor the names of its
-      contributors may be used to endorse or promote products derived
-      from this software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-
-*/
-
-#ifndef TORRENT_MAX_PATH_HPP_INCLUDED
-#define TORRENT_MAX_PATH_HPP_INCLUDED
-
-// on windows, NAME_MAX refers to Unicode characters
-// on linux it refers to bytes (utf-8 encoded)
-// TODO: Make this count Unicode characters instead of bytes on windows
-
-// windows
-#if defined FILENAME_MAX
-#define TORRENT_MAX_PATH FILENAME_MAX
-
-// beos
-#elif defined B_PATH_NAME_LENGTH
-#define TORRENT_MAX_PATH B_PATH_NAME_LENGTH
-
-// solaris
-#elif defined MAXPATH
-#define TORRENT_MAX_PATH MAXPATH
-
-// none of the above
-#else
-// this is the maximum number of characters in a
-// path element / filename on windows and also on many filesystems commonly used
-// on linux
-#define TORRENT_MAX_PATH 255
-
-#ifdef _MSC_VER
-#pragma message ( "unknown platform, assuming the longest path is 255" )
-#else
-#warning "unknown platform, assuming the longest path is 255"
-#endif
-
-#endif // FILENAME_MAX
-
-#endif // TORRENT_MAX_PATH_HPP_INCLUDED

include/libtorrent/aux_/path.hpp

@@ -69,8 +69,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <sys/types.h>
 #include <dirent.h> // for DIR
 
-#include "libtorrent/aux_/max_path.hpp" // for TORRENT_MAX_PATH
-
 #undef _FILE_OFFSET_BITS
 
 #endif

include/libtorrent/config.hpp

@@ -229,9 +229,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #define TORRENT_USE_GETADAPTERSADDRESSES 1
 #define TORRENT_HAS_SALEN 0
 #define TORRENT_USE_GETIPFORWARDTABLE 1
-#ifndef TORRENT_USE_UNC_PATHS
 #define TORRENT_USE_UNC_PATHS 1
-#endif
 // these are emulated on windows
 #define TORRENT_USE_PREADV 1
 #define TORRENT_USE_PWRITEV 1
@@ -273,9 +271,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #endif
 #define TORRENT_USE_RLIMIT 0
 #define TORRENT_HAS_FALLOCATE 0
-#ifndef TORRENT_USE_UNC_PATHS
 #define TORRENT_USE_UNC_PATHS 1
-#endif
 // these are emulated on windows
 #define TORRENT_USE_PREADV 1
 #define TORRENT_USE_PWRITEV 1

include/libtorrent/file.hpp

@@ -70,8 +70,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <sys/types.h>
 #include <dirent.h> // for DIR
 
-#include "libtorrent/aux_/max_path.hpp" // for TORRENT_MAX_PATH
-
 #undef _FILE_OFFSET_BITS
 
 #endif

src/alert.cpp

@@ -51,7 +51,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #endif
 
 #include "libtorrent/aux_/escape_string.hpp" // for convert_from_native
-#include "libtorrent/aux_/max_path.hpp" // for TORRENT_MAX_PATH
 
 namespace libtorrent {
 

src/create_torrent.cpp

@@ -32,7 +32,6 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #include "libtorrent/create_torrent.hpp"
 #include "libtorrent/utf8.hpp"
-#include "libtorrent/aux_/escape_string.hpp" // for convert_to_wstring
 #include "libtorrent/disk_io_thread.hpp"
 #include "libtorrent/aux_/merkle.hpp" // for merkle_*()
 #include "libtorrent/torrent_info.hpp"
@@ -69,16 +68,17 @@ namespace {
 
 	file_flags_t get_file_attributes(std::string const& p)
 	{
+		auto const path = convert_to_native_path_string(p);
+
 #ifdef TORRENT_WINDOWS
 		WIN32_FILE_ATTRIBUTE_DATA attr;
-		std::wstring path = convert_to_wstring(p);
 		GetFileAttributesExW(path.c_str(), GetFileExInfoStandard, &attr);
 		if (attr.dwFileAttributes == INVALID_FILE_ATTRIBUTES) return {};
 		if (attr.dwFileAttributes & FILE_ATTRIBUTE_HIDDEN) return file_storage::flag_hidden;
 		return {};
 #else
 		struct ::stat s;
-		if (::lstat(convert_to_native(p).c_str(), &s) < 0) return {};
+		if (::lstat(path.c_str(), &s) < 0) return {};
 		file_flags_t file_attr = {};
 		if (s.st_mode & S_IXUSR)
 			file_attr |= file_storage::flag_executable;
@@ -94,12 +94,12 @@ namespace {
 		constexpr int MAX_SYMLINK_PATH = 200;
 
 		char buf[MAX_SYMLINK_PATH];
-		std::string f = convert_to_native(path);
+		std::string f = convert_to_native_path_string(path);
 		int char_read = int(readlink(f.c_str(), buf, MAX_SYMLINK_PATH));
 		if (char_read < 0) return "";
 		if (char_read < MAX_SYMLINK_PATH) buf[char_read] = 0;
 		else buf[0] = 0;
-		return convert_from_native(buf);
+		return convert_from_native_path(buf);
 	}
 #endif
 

src/file.cpp

@@ -84,13 +84,10 @@ struct iovec
 
 #include "libtorrent/aux_/alloca.hpp"
 #include "libtorrent/file.hpp"
-#include "libtorrent/aux_/path.hpp"
+#include "libtorrent/aux_/path.hpp" // for convert_to_native_path_string
 #include "libtorrent/string_util.hpp"
-#include "libtorrent/aux_/max_path.hpp" // for TORRENT_MAX_PATH
 #include <cstring>
 
-// for convert_to_wstring and convert_to_native
-#include "libtorrent/aux_/escape_string.hpp"
 #include "libtorrent/assert.hpp"
 #include "libtorrent/aux_/throw.hpp"
 
@@ -391,7 +388,7 @@ static_assert(!(open_mode::sparse & open_mode::attribute_mask), "internal flags
 #ifdef TORRENT_WINDOWS
 		return convert_from_native_path(m_fd.cFileName);
 #else
-		return convert_from_native(m_name);
+		return convert_from_native_path(m_name.c_str());
 #endif
 	}
 

src/path.cpp

@@ -71,11 +71,9 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/aux_/path.hpp"
 #include "libtorrent/file.hpp" // for directory
 #include "libtorrent/string_util.hpp"
-#include "libtorrent/aux_/max_path.hpp" // for TORRENT_MAX_PATH
 #include <cstring>
 
-// for convert_to_wstring and convert_to_native
+#include "libtorrent/aux_/escape_string.hpp" // for convert_to_native
-#include "libtorrent/aux_/escape_string.hpp"
 #include "libtorrent/assert.hpp"
 #include "libtorrent/aux_/throw.hpp"
 
@@ -132,7 +130,11 @@ namespace libtorrent {
 	}
 
 #if defined TORRENT_WINDOWS
-	std::string convert_from_native_path(wchar_t const* s) { return convert_from_wstring(s); }
+	std::string convert_from_native_path(wchar_t const* s)
+	{
+		if (s[0] == L'\\' && s[1] == L'\\' && s[2] == L'?' && s[3] == L'\\') s += 4;
+		return convert_from_wstring(s);
+	}
 #else
 	std::string convert_from_native_path(char const* s) { return convert_from_native(s); }
 #endif
@@ -165,23 +167,13 @@ namespace {
 
 	native_path_string convert_to_native_path_string(std::string const& path)
 	{
-#ifdef TORRENT_WINDOWS
 #if TORRENT_USE_UNC_PATHS
-		std::string prepared_path;
 		// UNC paths must be absolute
 		// network paths are already UNC paths
-		if (path.substr(0,2) == "\\\\")
+		std::string prepared_path = complete(path);
-			prepared_path = path;
+		if (prepared_path.substr(0,2) != "\\\\")
-		else
+			prepared_path = "\\\\?\\" + prepared_path;
-		{
-			std::string sep_path = path;
-			std::replace(sep_path.begin(), sep_path.end(), '/', '\\');
-			prepared_path = "\\\\?\\" + (is_complete(sep_path) ? sep_path : complete(sep_path));
-		}
-#else
-		std::string prepared_path = path;
 		std::replace(prepared_path.begin(), prepared_path.end(), '/', '\\');
-#endif
 
 		return convert_to_wstring(prepared_path);
 #else // TORRENT_WINDOWS

src/storage.cpp

@@ -73,8 +73,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/disk_buffer_holder.hpp"
 #include "libtorrent/stat_cache.hpp"
 #include "libtorrent/hex.hpp" // to_hex
-// for convert_to_wstring and convert_to_native
+//#include "libtorrent/aux_/escape_string.hpp"
-#include "libtorrent/aux_/escape_string.hpp"
 
 namespace libtorrent {
 
@@ -233,7 +232,7 @@ namespace libtorrent {
 
 #ifdef TORRENT_WINDOWS
 		// don't do full file allocations on network drives
-		std::wstring file_name = convert_to_wstring(m_save_path);
+		auto const file_name = convert_to_native_path_string(m_save_path);
 		int const drive_type = GetDriveTypeW(file_name.c_str());
 
 		if (drive_type == DRIVE_REMOTE)

src/torrent.cpp

@@ -8155,7 +8155,7 @@ bool is_downloading_state(int const st)
 		if (m_storage && file >= file_index_t(0))
 		{
 			file_storage const& st = m_torrent_file->files();
-			return combine_path(m_save_path, st.file_path(file));
+			return st.file_path(file, m_save_path);
 		}
 		else
 		{

src/torrent_info.cpp

@@ -192,6 +192,8 @@ namespace libtorrent {
 		}
 
 #if !TORRENT_USE_UNC_PATHS && defined TORRENT_WINDOWS
+#pragma message ("building for windows without UNC paths is deprecated")
+
 		// if we're not using UNC paths on windows, there
 		// are certain filenames we're not allowed to use
 		static const char const* reserved_names[] =

test/main.cpp

@@ -230,12 +230,12 @@ void change_directory(std::string const& f, error_code& ec)
 {
 	ec.clear();
 
+	native_path_string const n = convert_to_native_path_string(f);
+
 #ifdef TORRENT_WINDOWS
-	native_path_string const n = convert_to_wstring(f);
 	if (SetCurrentDirectoryW(n.c_str()) == 0)
 		ec.assign(GetLastError(), system_category());
 #else
-	native_path_string const n = convert_to_native_path_string(f);
 	int ret = ::chdir(n.c_str());
 	if (ret != 0)
 		ec.assign(errno, system_category());
@@ -430,6 +430,7 @@ int EXPORT main(int argc, char const* argv[])
 			return 1;
 		}
 
+		std::printf("cwd: %s\n", unit_dir.c_str());
 		unit_test_t& t = _g_unit_tests[i];
 
 		if (redirect_stdout || redirect_stderr)

test/setup_transfer.cpp

@@ -810,7 +810,8 @@ setup_transfer(lt::session* ses1, lt::session* ses2, lt::session* ses3
 	{
 		error_code ec;
 		create_directory("tmp1" + suffix, ec);
-		std::ofstream file(combine_path("tmp1" + suffix, "temporary").c_str());
+		std::string const file_path = combine_path("tmp1" + suffix, "temporary");
+		std::ofstream file(file_path.c_str());
 		t = ::create_torrent(&file, "temporary", piece_size, 9, false);
 		file.close();
 		if (clear_files)
@@ -818,7 +819,7 @@ setup_transfer(lt::session* ses1, lt::session* ses2, lt::session* ses3
 			remove_all(combine_path("tmp2" + suffix, "temporary"), ec);
 			remove_all(combine_path("tmp3" + suffix, "temporary"), ec);
 		}
-		std::printf("generated torrent: %s tmp1%s/temporary\n", aux::to_hex(t->info_hash()).c_str(), suffix.c_str());
+		std::printf("generated torrent: %s %s\n", aux::to_hex(t->info_hash()).c_str(), file_path.c_str());
 	}
 	else
 	{

test/test_file.cpp

@@ -39,6 +39,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <vector>
 #include <set>
 #include <thread>
+#include <iostream>
 
 using namespace lt;
 
@@ -56,11 +57,13 @@ int touch_file(std::string const& filename, int size)
 	file f;
 	error_code ec;
 	if (!f.open(filename, open_mode::write_only, ec)) return -1;
+	TEST_EQUAL(ec, error_code());
 	if (ec) return -1;
 	iovec_t b = {v};
 	std::int64_t written = f.writev(0, b, ec);
 	if (written != int(v.size())) return -3;
 	if (ec) return -3;
+	TEST_EQUAL(ec, error_code());
 	return 0;
 }
 
@@ -447,31 +450,31 @@ TORRENT_TEST(stat_file)
 	TEST_EQUAL(ec, boost::system::errc::no_such_file_or_directory);
 }
 
-// specificaly UNC tests
+// UNC tests
 #if TORRENT_USE_UNC_PATHS
 
 namespace {
-std::tuple<int, bool> fill_current_directory_caps()
+std::tuple<int, bool> current_directory_caps()
 {
 #ifdef TORRENT_WINDOWS
-	error_code ec;
+	DWORD maximum_component_length = FILENAME_MAX;
-	DWORD dw_maximum_component_length;
+	DWORD file_system_flags = 0;
-	DWORD dw_file_system_flags;
+	if (GetVolumeInformation(nullptr
-	if (!GetVolumeInformationA(nullptr, nullptr, 0, nullptr, &dw_maximum_component_length, &dw_file_system_flags, nullptr, 0))
+		, nullptr, 0, nullptr
+		, &maximum_component_length, &file_system_flags, nullptr, 0) == 0)
 	{
-		ec.assign(GetLastError(), system_category());
+		error_code ec(GetLastError(), system_category());
-		std::printf("GetVolumeInformation: [%s] %s\n"
+		std::printf("GetVolumeInformation: [%s : %d] %s\n"
-			, ec.category().name(), ec.message().c_str());
+			, ec.category().name(), ec.value(), ec.message().c_str());
-		return std::make_tuple(0, false);
+		// ignore errors, this is best-effort
 	}
-	int maximum_component_length = int(dw_maximum_component_length);
+	bool const support_hard_links = ((file_system_flags & FILE_SUPPORTS_HARD_LINKS) != 0);
-	bool support_hard_links = ((dw_file_system_flags & FILE_SUPPORTS_HARD_LINKS) != 0);
+	return std::make_tuple(int(maximum_component_length), support_hard_links);
-	return std::make_tuple(maximum_component_length, support_hard_links);
 #else
-	return std::make_tuple(TORRENT_MAX_PATH, true);
+	return std::make_tuple(255, true);
 #endif
 }
-}
+} // anonymous namespace
 
 TORRENT_TEST(unc_tests)
 {
@@ -497,7 +500,7 @@ TORRENT_TEST(unc_tests)
 
 	for (std::string special_name : special_names)
 	{
-		TEST_EQUAL(touch_file(special_name, 10), 0);
+		touch_file(special_name, 10);
 		TEST_CHECK(lt::exists(special_name));
 		lt::remove(special_name, ec);
 		TEST_EQUAL(ec, error_code());
@@ -506,40 +509,63 @@ TORRENT_TEST(unc_tests)
 
 	int maximum_component_length;
 	bool support_hard_links;
-	std::tie(maximum_component_length, support_hard_links) = fill_current_directory_caps();
+	std::tie(maximum_component_length, support_hard_links) = current_directory_caps();
 
-	if (maximum_component_length > 0)
+	std::cout << "max file path component length: " << maximum_component_length << "\n"
-	{
+		<< "support hard links: " << (support_hard_links?"yes":"no") << "\n";
-		std::string long_component_name;
+
-		long_component_name.resize(size_t(maximum_component_length));
+	std::string long_dir_name;
+	maximum_component_length -= 12;
+	long_dir_name.resize(size_t(maximum_component_length));
 	for (int i = 0; i < maximum_component_length; ++i)
-			long_component_name[i] = static_cast<char>((i % 26) + 'A');
+		long_dir_name[i] = static_cast<char>((i % 26) + 'A');
 
-		std::string long_file_name1 =  combine_path(long_component_name, long_component_name);
+	std::string long_file_name1 = combine_path(long_dir_name, long_dir_name);
 	long_file_name1.back() = '1';
-		std::string long_file_name2 { long_file_name1 };
+	std::string long_file_name2 = long_file_name1;
 	long_file_name2.back() = '2';
 
-		lt::create_directory(long_component_name, ec);
+	lt::create_directory(long_dir_name, ec);
 	TEST_EQUAL(ec, error_code());
-		TEST_CHECK(lt::exists(long_component_name));
+	if (ec)
-		TEST_CHECK(lt::is_directory(long_component_name, ec));
+	{
+		std::cout << "create_directory \"" << long_dir_name << "\" failed: " << ec.message() << "\n";
+		std::wcout << convert_to_native_path_string(long_dir_name) << L"\n";
+	}
+	TEST_CHECK(lt::exists(long_dir_name));
+	TEST_CHECK(lt::is_directory(long_dir_name, ec));
+	TEST_EQUAL(ec, error_code());
+	if (ec)
+	{
+		std::cout << "is_directory \"" << long_dir_name << "\" failed " << ec.message() << "\n";
+		std::wcout << convert_to_native_path_string(long_dir_name) << L"\n";
+	}
 
-		TEST_EQUAL(touch_file(long_file_name1, 10), 0);
+	touch_file(long_file_name1, 10);
 	TEST_CHECK(lt::exists(long_file_name1));
 
 	lt::rename(long_file_name1, long_file_name2, ec);
 	TEST_EQUAL(ec, error_code());
+	if (ec)
+	{
+		std::cout << "rename \"" << long_file_name1 << "\" failed " << ec.message() << "\n";
+		std::wcout << convert_to_native_path_string(long_file_name1) << L"\n";
+	}
 	TEST_CHECK(!lt::exists(long_file_name1));
 	TEST_CHECK(lt::exists(long_file_name2));
 
 	lt::copy_file(long_file_name2, long_file_name1, ec);
 	TEST_EQUAL(ec, error_code());
+	if (ec)
+	{
+		std::cout << "copy_file \"" << long_file_name2 << "\" failed " << ec.message() << "\n";
+		std::wcout << convert_to_native_path_string(long_file_name2) << L"\n";
+	}
 	TEST_CHECK(lt::exists(long_file_name1));
 
 	std::set<std::string> files;
 
-		for (lt::directory i(long_component_name, ec); !i.done(); i.next(ec))
+	for (lt::directory i(long_dir_name, ec); !i.done(); i.next(ec))
 	{
 		std::string f = i.file();
 		files.insert(f);
@@ -549,6 +575,11 @@ TORRENT_TEST(unc_tests)
 
 	lt::remove(long_file_name1, ec);
 	TEST_EQUAL(ec, error_code());
+	if (ec)
+	{
+		std::cout << "remove \"" << long_file_name1 << "\" failed " << ec.message() << "\n";
+		std::wcout << convert_to_native_path_string(long_file_name1) << L"\n";
+	}
 	TEST_CHECK(!lt::exists(long_file_name1));
 
 	if (support_hard_links)
@@ -562,7 +593,6 @@ TORRENT_TEST(unc_tests)
 		TEST_CHECK(!lt::exists(long_file_name1));
 	}
 }
-}
 
 TORRENT_TEST(unc_paths)
 {