Initial cFile implementation (using stdio FILE) and test in cChunkMap

git-svn-id: http://mc-server.googlecode.com/svn/trunk@192 0a769ca7-a7f5-676a-18bf-c427514a06d6

source/cFile.cpp

@@ -0,0 +1,200 @@
+
+// cFile.cpp
+
+// Implements the cFile class providing an OS-independent abstraction of a file.
+
+#include "Globals.h"  // NOTE: MSVC stupidness requires this to be the same across all modules
+
+#include "cFile.h"
+
+
+
+
+
+
+/// Simple constructor - creates an unopened file object, use Open() to open / create a real file
+cFile::cFile(void) :
+	#ifdef USE_STDIO_FILE
+	m_File(NULL)
+	#else
+	m_File(INVALID_HANDLE_VALUE)
+	#endif  // USE_STDIO_FILE
+{
+	// Nothing needed yet
+}
+
+
+
+
+
+/// Constructs and opens / creates the file specified, use IsOpen() to check for success
+cFile::cFile(const char * iFileName, EMode iMode) :
+	#ifdef USE_STDIO_FILE
+	m_File(NULL)
+	#else
+	m_File(INVALID_HANDLE_VALUE)
+	#endif  // USE_STDIO_FILE
+{
+	Open(iFileName, iMode);
+}
+
+
+
+
+
+/// Auto-closes the file, if open
+cFile::~cFile()
+{
+	if (IsOpen())
+	{
+		Close();
+	}
+}
+
+
+
+
+
+bool cFile::Open(const char * iFileName, EMode iMode)
+{
+	assert(!IsOpen());  // You should close the file before opening another one
+	
+	if (IsOpen())
+	{
+		Close();
+	}
+	
+	const char * Mode = NULL;
+	switch (iMode)
+	{
+		case fmRead:      Mode = "rb";  break;
+		case fmWrite:     Mode = "wb";  break;
+		case fmReadWrite: Mode = "ab+"; break;
+		default:
+		{
+			assert(!"Unhandled file mode");
+			return false;
+		}
+	}
+	m_File = fopen(iFileName, Mode);
+	return (m_File != NULL);
+}
+
+
+
+
+
+void cFile::Close(void)
+{
+	assert(IsOpen());  // You should not close file objects that don't have an open file.
+	
+	if (!IsOpen())
+	{
+		return;
+	}
+
+	fclose(m_File);
+}
+
+
+
+
+
+bool cFile::IsOpen(void) const
+{
+	return (m_File != NULL);
+}
+
+
+
+
+
+bool cFile::IsEOF(void) const
+{
+	assert(IsOpen());
+	
+	if (!IsOpen())
+	{
+		// Unopened files behave as at EOF
+		return true;
+	}
+	
+	return (feof(m_File) != 0);
+}
+
+
+
+
+
+/// Reads  up to iNumBytes bytes into iBuffer, returns the number of bytes actually read,    or -1 on failure; asserts if not open
+int cFile::Read (void * iBuffer, int iNumBytes)
+{
+	assert(IsOpen());
+	
+	if (!IsOpen())
+	{
+		return -1;
+	}
+	
+	return fread(iBuffer, 1, iNumBytes, m_File);  // fread() returns the portion of Count parameter actually read, so we need to send iNumBytes as Count
+}
+
+
+
+
+
+/// Writes up to iNumBytes bytes from iBuffer, returns the number of bytes actually written, or -1 on failure; asserts if not open
+int cFile::Write(const void * iBuffer, int iNumBytes)
+{
+	assert(IsOpen());
+	
+	if (!IsOpen())
+	{
+		return -1;
+	}
+
+	return fwrite(iBuffer, 1, iNumBytes, m_File);  // fwrite() returns the portion of Count parameter actually written, so we need to send iNumBytes as Count
+}
+
+
+
+
+
+/// Seeks to iPosition bytes from file start, returns old position or -1 for failure
+int cFile::Seek (int iPosition)
+{
+	assert(IsOpen());
+	
+	if (!IsOpen())
+	{
+		return -1;
+	}
+	
+	if (fseek(m_File, iPosition, SEEK_SET) != 0)
+	{
+		return -1;
+	}
+	return ftell(m_File);
+}
+
+
+
+
+
+
+/// Returns the current position (bytes from file start)
+int cFile::Tell (void) const
+{
+	assert(IsOpen());
+	
+	if (!IsOpen())
+	{
+		return -1;
+	}
+	
+	return ftell(m_File);
+}
+
+
+
+