merge File::linkTo() from 1.8.1

Foundation/include/Poco/File.h

@@ -60,6 +60,13 @@ class Foundation_API File: private FileImpl
 public:
 	typedef FileSizeImpl FileSize;
 
+	enum LinkType
+		/// Type of link for linkTo().
+	{
+		LINK_HARD     = 0, /// hard link
+		LINK_SYMBOLIC = 1  /// symbolic link
+	};
+
 	File();
 		/// Creates the file.
 
@@ -186,6 +193,14 @@ public:
 	void renameTo(const std::string& path);
 		/// Renames the file to the new name.
 
+	void linkTo(const std::string& path, LinkType type = LINK_SYMBOLIC) const;
+		/// Creates a link (symbolic or hard, depending on type argument)
+		/// at the given path to the file or directory.
+		///
+		/// May not be supported on all platforms.
+		/// Furthermore, some operating systems do not allow creating
+		/// hard links to directories.
+
 	void remove(bool recursive = false);
 		/// Deletes the file. If recursive is true and the
 		/// file is a directory, recursively deletes all

Foundation/include/Poco/File_UNIX.h

@@ -54,6 +54,7 @@ protected:
 	void setExecutableImpl(bool flag = true);		
 	void copyToImpl(const std::string& path) const;
 	void renameToImpl(const std::string& path);
+	void linkToImpl(const std::string& path, int type) const;
 	void removeImpl();
 	bool createFileImpl();
 	bool createDirectoryImpl();

Foundation/include/Poco/File_VX.h

@@ -53,6 +53,7 @@ protected:
 	void setExecutableImpl(bool flag = true);		
 	void copyToImpl(const std::string& path) const;
 	void renameToImpl(const std::string& path);
+	void linkToImpl(const std::string& path, int type) const;
 	void removeImpl();
 	bool createFileImpl();
 	bool createDirectoryImpl();

Foundation/include/Poco/File_WIN32.h

@@ -54,6 +54,7 @@ protected:
 	void setExecutableImpl(bool flag = true);
 	void copyToImpl(const std::string& path) const;
 	void renameToImpl(const std::string& path);
+	void linkToImpl(const std::string& path, int type) const;
 	void removeImpl();
 	bool createFileImpl();
 	bool createDirectoryImpl();

Foundation/include/Poco/File_WINCE.h

@@ -54,6 +54,7 @@ protected:
 	void setExecutableImpl(bool flag = true);		
 	void copyToImpl(const std::string& path) const;
 	void renameToImpl(const std::string& path);
+	void linkToImpl(const std::string& path, int type) const;
 	void removeImpl();
 	bool createFileImpl();
 	bool createDirectoryImpl();

Foundation/src/File.cpp

@@ -260,6 +260,12 @@ void File::renameTo(const std::string& rPath)
 }
 
 
+void File::linkTo(const std::string& rPath, LinkType type) const
+{
+	linkToImpl(rPath, type);
+}
+
+
 void File::remove(bool recursive)
 {
 	if (recursive && !isLink() && isDirectory())

Foundation/src/File_UNIX.cpp

@@ -414,6 +414,23 @@ void FileImpl::renameToImpl(const std::string& path)
 }
 
 
+void FileImpl::linkToImpl(const std::string& path, int type) const
+{
+	poco_assert (!_path.empty());
+
+	if (type == 0)
+	{
+		if (link(_path.c_str(), path.c_str()) != 0)
+			handleLastErrorImpl(_path);
+	}
+	else
+	{
+		if (symlink(_path.c_str(), path.c_str()) != 0)
+			handleLastErrorImpl(_path);
+	}
+}
+
+
 void FileImpl::removeImpl()
 {
 	poco_assert (!_path.empty());

Foundation/src/File_VX.cpp

@@ -285,6 +285,12 @@ void FileImpl::renameToImpl(const std::string& path)
 }
 
 
+void FileImpl::linkToImpl(const std::string& path, int type) const
+{
+	throw Poco::NotImplementedException("File::linkTo() is not available on this platform");
+}
+
+
 void FileImpl::removeImpl()
 {
 	poco_assert (!_path.empty());

Foundation/src/File_WIN32.cpp

@@ -167,7 +167,12 @@ bool FileImpl::isDirectoryImpl() const
 
 bool FileImpl::isLinkImpl() const
 {
-	return false;
+	poco_assert (!_path.empty());
+
+	DWORD attr = GetFileAttributesW(_upath.c_str());
+	if (attr == INVALID_FILE_ATTRIBUTES)
+		handleLastErrorImpl(_path);
+	return (attr & FILE_ATTRIBUTE_DIRECTORY) == 0 && (attr & FILE_ATTRIBUTE_REPARSE_POINT) != 0;
 }
 
 
@@ -308,6 +313,35 @@ void FileImpl::renameToImpl(const std::string& path)
 }
 
 
+void FileImpl::linkToImpl(const std::string& path, int type) const
+{
+	poco_assert (!_path.empty());
+
+	std::wstring upath;
+	convertPath(path, upath);
+
+	if (type == 0)
+	{
+		if (CreateHardLinkW(upath.c_str(), _upath.c_str(), NULL) == 0)
+			handleLastErrorImpl(_path);
+	}
+	else
+	{
+#if _WIN32_WINNT >= 0x0600 && defined(SYMBOLIC_LINK_FLAG_DIRECTORY)
+		DWORD flags = 0;
+		if (isDirectoryImpl()) flags |= SYMBOLIC_LINK_FLAG_DIRECTORY;
+#ifdef SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE
+		flags |= SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;
+#endif
+		if (CreateSymbolicLinkW(upath.c_str(), _upath.c_str(), flags) == 0)
+			handleLastErrorImpl(_path);
+#else
+		throw Poco::NotImplementedException("Symbolic link support not available in used version of the Windows SDK");
+#endif
+	}
+}
+
+
 void FileImpl::removeImpl()
 {
 	poco_assert (!_path.empty());

Foundation/src/File_WINCE.cpp

@@ -299,6 +299,12 @@ void FileImpl::renameToImpl(const std::string& path)
 }
 
 
+void FileImpl::linkToImpl(const std::string& path, int type) const
+{
+	throw Poco::NotImplementedException("File::linkTo() is not available on this platform");
+}
+
+
 void FileImpl::removeImpl()
 {
 	poco_assert (!_path.empty());