Added fs::file_ptr, fom::rewrite, cleanup

Utilities/File.cpp

@@ -96,6 +96,7 @@ bool truncate_file(const std::string& file, u64 length)
 }
 
 #else
+#include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <dirent.h>
@@ -306,14 +307,16 @@ bool fs::rename(const std::string& from, const std::string& to)
 
 int OSCopyFile(const char* source, const char* destination, bool overwrite)
 {
-	/* This function was taken from http://stackoverflow.com/questions/2180079/how-can-i-copy-a-file-on-unix-using-c */
+	/* Source: http://stackoverflow.com/questions/2180079/how-can-i-copy-a-file-on-unix-using-c */
 
-	int input, output;
-	if ((input = open(source, O_RDONLY)) == -1)
+	const int input = open(source, O_RDONLY);
+	if (input == -1)
 	{
 		return -1;
 	}
-	if ((output = open(destination, O_WRONLY | O_CREAT | (overwrite ? O_TRUNC : O_EXCL), 0666)) == -1)
+
+	const int output = open(destination, O_WRONLY | O_CREAT | (overwrite ? O_TRUNC : O_EXCL), 0666);
+	if (output == -1)
 	{
 		close(input);
 		return -1;
@@ -322,13 +325,12 @@ int OSCopyFile(const char* source, const char* destination, bool overwrite)
 	//Here we use kernel-space copying for performance reasons
 #if defined(__APPLE__) || defined(__FreeBSD__)
 	//fcopyfile works on FreeBSD and OS X 10.5+ 
-	int result = fcopyfile(input, output, 0, COPYFILE_ALL);
+	const int result = fcopyfile(input, output, 0, COPYFILE_ALL);
 #else
 	//sendfile will work with non-socket output (i.e. regular file) on Linux 2.6.33+
 	off_t bytesCopied = 0;
 	struct stat fileinfo = { 0 };
-	fstat(input, &fileinfo);
-	int result = sendfile(output, input, &bytesCopied, fileinfo.st_size) == -1 ? -1 : 0;
+	const int result = fstat(input, &fileinfo) == -1 || sendfile(output, input, &bytesCopied, fileinfo.st_size) == -1 ? -1 : 0;
 #endif
 
 	close(input);
@@ -662,6 +664,36 @@ fs::dir::~dir()
 	}
 }
 
+void fs::file_ptr::reset(const file& f)
+{
+	reset();
+
+	if (f)
+	{
+#ifdef _WIN32
+		const HANDLE handle = ::CreateFileMapping((HANDLE)f.m_fd, NULL, PAGE_READONLY, 0, 0, NULL);
+		m_ptr = (char*)::MapViewOfFile(handle, FILE_MAP_READ, 0, 0, 0);
+		m_size = f.size();
+		::CloseHandle(handle);
+#else
+		m_ptr = (char*)::mmap(nullptr, m_size = f.size(), PROT_READ, MAP_SHARED, f.m_fd, 0);
+		if (m_ptr == (void*)-1) m_ptr = nullptr;
+#endif
+	}
+}
+
+void fs::file_ptr::reset()
+{
+	if (m_ptr)
+	{
+#ifdef _WIN32
+		::UnmapViewOfFile(m_ptr);
+#else
+		::munmap(m_ptr, m_size);
+#endif
+	}
+}
+
 bool fs::dir::open(const std::string& dirname)
 {
 	this->close();

Utilities/File.h

@@ -11,12 +11,14 @@ namespace fom // file open mode
 {
 	enum : u32
 	{
-		read = 1 << 0,
-		write = 1 << 1,
-		append = 1 << 2,
-		create = 1 << 3,
-		trunc = 1 << 4,
-		excl = 1 << 5,
+		read = 1 << 0, // enable reading
+		write = 1 << 1, // enable writing
+		append = 1 << 2, // enable appending (always write to the end of file)
+		create = 1 << 3, // create file if it doesn't exist
+		trunc = 1 << 4, // clear opened file if it's not empty
+		excl = 1 << 5, // failure if the file already exists (used with `create`)
+
+		rewrite = write | create | trunc, // write + create + trunc
 	};
 };
 
@@ -81,6 +83,8 @@ namespace fs
 
 		handle_type m_fd = null;
 
+		friend class file_ptr;
+
 	public:
 		file() = default;
 
@@ -133,14 +137,63 @@ namespace fs
 		// Write the data to the file and return the amount of data actually written
 		u64 write(const void* buffer, u64 count) const;
 
-		// Write std::string
-		u64 write(const std::string& string) const { return write(string.data(), string.size()); }
-
 		// Move file pointer
 		u64 seek(s64 offset, fsm seek_mode = fsm::begin) const;
 
 		// Get file size
 		u64 size() const;
+
+		// Write std::string
+		const file& operator <<(const std::string& str) const
+		{
+			CHECK_ASSERTION(write(str.data(), str.size()) == str.size());
+			return *this;
+		}
+	};
+
+	class file_ptr final
+	{
+		char* m_ptr = nullptr;
+		u64 m_size;
+
+	public:
+		file_ptr() = default;
+
+		file_ptr(file_ptr&& right)
+			: m_ptr(right.m_ptr)
+			, m_size(right.m_size)
+		{
+			right.m_ptr = 0;
+		}
+
+		file_ptr& operator =(file_ptr&& right)
+		{
+			std::swap(m_ptr, right.m_ptr);
+			std::swap(m_size, right.m_size);
+			return *this;
+		}
+
+		file_ptr(const file& f)
+		{
+			reset(f);
+		}
+
+		~file_ptr()
+		{
+			reset();
+		}
+
+		// Open file mapping
+		void reset(const file& f);
+		
+		// Close file mapping
+		void reset();
+
+		// Get pointer
+		operator char*() const
+		{
+			return m_ptr;
+		}
 	};
 
 	class dir final

Utilities/Log.cpp

@@ -94,7 +94,7 @@ struct FileListener : LogListener
 	bool mPrependChannelName;
 
 	FileListener(const std::string& name = _PRGNAME_, bool prependChannel = true)
-		: mFile(rPlatform::getConfigDir() + name + ".log", fom::write | fom::create | fom::trunc)
+		: mFile(rPlatform::getConfigDir() + name + ".log", fom::rewrite)
 		, mPrependChannelName(prependChannel)
 	{
 		if (!mFile)
@@ -120,7 +120,7 @@ struct FileListener : LogListener
 			}
 		}
 
-		mFile.write(text.c_str(), text.size());
+		mFile << text;
 	}
 };