From b943a9b0572fe3cfd6c8892b4d9b1de4c4871417 Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Fri, 8 Mar 2013 09:56:19 +0000
Subject: [PATCH] merged long-name truncation fix from RC_0_16

---
 ChangeLog            |  1 +
 src/torrent_info.cpp | 51 +++++++++++++++++++++++++++++++++-----------
 2 files changed, 39 insertions(+), 13 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a26cf6dfe..e8847730a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,7 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* fix long filename truncation on windows
 	* distinguish file open mode when checking files and downloading/seeding with bittorrent. updates storage interface
 	* improve file_storage::map_file when dealing with invalid input
 	* improve handling of invalid utf-8 sequences in strings in torrent files
diff --git a/src/torrent_info.cpp b/src/torrent_info.cpp
index 9f903df95..81ec99ead 100644
--- a/src/torrent_info.cpp
+++ b/src/torrent_info.cpp
@@ -189,23 +189,48 @@ namespace libtorrent
 		return true;
 	}
 
-	TORRENT_EXTRA_EXPORT void trim_path_element(std::string& path_element)
+	TORRENT_EXTRA_EXPORT void trim_path_element(std::string& element)
 	{
 		const int max_path_len = TORRENT_MAX_PATH;
-		if (int(path_element.size()) > max_path_len)
+
+		// on windows, the max path is expressed in
+		// unicode characters, not bytes
+#if defined TORRENT_WINDOWS
+		std::wstring path_element;
+		utf8_wchar(element, path_element);
+		if (path_element.size() <= max_path_len) return;
+
+		// truncate filenames that are too long. But keep extensions!
+		std::wstring ext;
+		wchar_t const* ext1 = wcsrchr(path_element.c_str(), '.');
+		if (ext1 != NULL) ext = ext1;
+
+		if (ext.size() > 15)
 		{
-			// truncate filenames that are too long. But keep extensions!
-			std::string ext = extension(path_element);
-			if (ext.size() > 15)
-			{
-				path_element.resize(max_path_len);
-			}
-			else
-			{
-				path_element.resize(max_path_len - ext.size());
-				path_element += ext;
-			}
+			path_element.resize(max_path_len);
 		}
+		else
+		{
+			path_element.resize(max_path_len - ext.size());
+			path_element += ext;
+		}
+		wchar_utf8(path_element, element);
+#else
+		std::string& path_element = element;
+		if (int(path_element.size()) <= max_path_len) return;
+
+		// truncate filenames that are too long. But keep extensions!
+		std::string ext = extension(path_element);
+		if (ext.size() > 15)
+		{
+			path_element.resize(max_path_len);
+		}
+		else
+		{
+			path_element.resize(max_path_len - ext.size());
+			path_element += ext;
+		}
+#endif
 	}
 
 	TORRENT_EXTRA_EXPORT std::string sanitize_path(std::string const& p)