Give access to LimitReadFiles.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2304 dfc29bdd-3216-0410-991c-e03cc46cb475

include/IFileSystem.h

@@ -53,6 +53,19 @@ public:
 	*/
 	virtual IReadFile* createMemoryReadFile(void* memory, s32 len, const core::string<c16>& fileName, bool deleteMemoryWhenDropped=false) =0;
 
+	//! Creates an IReadFile interface for accessing files inside files.
+	/** This is useful e.g. for archives.
+	\param fileName: The name given to this file
+	\param alreadyOpenedFile: Pointer to the enclosing file
+	\param pos: Start of the file inside alreadyOpenedFile
+	\param areaSize: The length of the file
+	\return A pointer to the created file interface.
+	The returned pointer should be dropped when no longer needed.
+	See IReferenceCounted::drop() for more information.
+	*/
+	virtual IReadFile* createLimitReadFile(const core::string<c16>& fileName,
+			IReadFile* alreadyOpenedFile, long pos, long areaSize) =0;
+
 	//! Creates an IWriteFile interface for accessing memory like a file.
 	/** This allows you to use a pointer to memory where an IWriteFile is requested.
 		You are responsible for allocating enough memory.

source/Irrlicht/CFileSystem.cpp

@@ -16,6 +16,7 @@
 #include "os.h"
 #include "CAttributes.h"
 #include "CMemoryFile.h"
+#include "CLimitReadFile.h"
 
 #if defined (_IRR_WINDOWS_API_)
 	#if !defined ( _WIN32_WCE )
@@ -93,6 +94,18 @@ IReadFile* CFileSystem::createMemoryReadFile(void* memory, s32 len,
 		return new CMemoryFile(memory, len, fileName, deleteMemoryWhenDropped);
 }
 
+
+//! Creates an IReadFile interface for reading files inside files
+IReadFile* CFileSystem::createLimitReadFile(const core::string<c16>& fileName,
+		IReadFile* alreadyOpenedFile, long pos, long areaSize)
+{
+	if (!alreadyOpenedFile)
+		return 0;
+	else
+		return new CLimitReadFile(alreadyOpenedFile, pos, areaSize, fileName);
+}
+
+
 //! Creates an IReadFile interface for treating memory like a file.
 IWriteFile* CFileSystem::createMemoryWriteFile(void* memory, s32 len,
 		const core::string<c16>& fileName, bool deleteMemoryWhenDropped)

source/Irrlicht/CFileSystem.h

@@ -36,6 +36,9 @@ public:
 	//! Creates an IReadFile interface for accessing memory like a file.
 	virtual IReadFile* createMemoryReadFile(void* memory, s32 len, const core::string<c16>& fileName, bool deleteMemoryWhenDropped = false);
 
+	//! Creates an IReadFile interface for accessing files inside files
+	virtual IReadFile* createLimitReadFile(const core::string<c16>& fileName, IReadFile* alreadyOpenedFile, long pos, long areaSize);
+
 	//! Creates an IWriteFile interface for accessing memory like a file.
 	virtual IWriteFile* createMemoryWriteFile(void* memory, s32 len, const core::string<c16>& fileName, bool deleteMemoryWhenDropped=false);
 

source/Irrlicht/CLimitReadFile.cpp

@@ -11,9 +11,10 @@ namespace io
 {
 
 
-CLimitReadFile::CLimitReadFile(IReadFile* alreadyOpenedFile, long pos, long areaSize,
-							   const core::string<c16>& name)
-: Filename(name), AreaStart(0), AreaEnd(0), Pos(0), File(alreadyOpenedFile)
+CLimitReadFile::CLimitReadFile(IReadFile* alreadyOpenedFile, long pos,
+		long areaSize, const core::string<c16>& name)
+	: Filename(name), AreaStart(0), AreaEnd(0), Pos(0),
+	File(alreadyOpenedFile)
 {
 	#ifdef _DEBUG
 	setDebugName("CLimitReadFile");
@@ -35,19 +36,18 @@ CLimitReadFile::~CLimitReadFile()
 }
 
 
-
 //! returns how much was read
 s32 CLimitReadFile::read(void* buffer, u32 sizeToRead)
 {
 #if 1
-	if ( 0 == File )
+	if (0 == File)
 		return 0;
 
 	s32 r = AreaStart + Pos;
-	s32 toRead = core::s32_min( AreaEnd, r + sizeToRead ) - core::s32_max( AreaStart, r );
-	if ( toRead < 0 )
+	s32 toRead = core::s32_min(AreaEnd, r + sizeToRead) - core::s32_max(AreaStart, r);
+	if (toRead < 0)
 		return 0;
-	File->seek ( r );
+	File->seek(r);
 	r = File->read(buffer, toRead);
 	Pos += r;
 	return r;
@@ -65,14 +65,11 @@ s32 CLimitReadFile::read(void* buffer, u32 sizeToRead)
 }
 
 
-
 //! changes position in file, returns true if successful
-//! if relativeMovement==true, the pos is changed relative to current pos,
-//! otherwise from begin of file
 bool CLimitReadFile::seek(long finalPos, bool relativeMovement)
 {
 #if 1
-	Pos = core::s32_clamp ( finalPos + (relativeMovement ? Pos : 0 ), 0, AreaEnd - AreaStart );
+	Pos = core::s32_clamp(finalPos + (relativeMovement ? Pos : 0 ), 0, AreaEnd - AreaStart);
 	return true;
 #else
 	const long pos = File->getPos();
@@ -101,7 +98,6 @@ long CLimitReadFile::getSize() const
 }
 
 
-
 //! returns where in the file we are.
 long CLimitReadFile::getPos() const
 {
@@ -113,7 +109,6 @@ long CLimitReadFile::getPos() const
 }
 
 
-
 //! returns name of file
 const core::string<c16>& CLimitReadFile::getFileName() const
 {