Engine directory for ticket #1

Engine/source/core/fileio.h

@@ -0,0 +1,140 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#ifndef _FILEIO_H_
+#define _FILEIO_H_
+
+#ifndef _PLATFORM_H_
+#include "platform/platform.h"
+#endif
+
+class File
+{
+public:
+   /// What is the status of our file handle?
+   enum Status
+   {
+      Ok = 0,           ///< Ok!
+      IOError,          ///< Read or Write error
+      EOS,              ///< End of Stream reached (mostly for reads)
+      IllegalCall,      ///< An unsupported operation used.  Always accompanied by AssertWarn
+      Closed,           ///< Tried to operate on a closed stream (or detached filter)
+      UnknownError      ///< Catchall
+   };
+
+   /// How are we accessing the file?
+   enum AccessMode
+   {
+      Read         = 0,  ///< Open for read only, starting at beginning of file.
+      Write        = 1,  ///< Open for write only, starting at beginning of file; will blast old contents of file.
+      ReadWrite    = 2,  ///< Open for read-write.
+      WriteAppend  = 3   ///< Write-only, starting at end of file.
+   };
+
+   /// Flags used to indicate what we can do to the file.
+   enum Capability
+   {
+      FileRead         = BIT(0),
+      FileWrite        = BIT(1)
+   };
+
+private:
+   void *handle;           ///< Pointer to the file handle.
+   Status currentStatus;   ///< Current status of the file (Ok, IOError, etc.).
+   U32 capability;         ///< Keeps track of file capabilities.
+
+   File(const File&);              ///< This is here to disable the copy constructor.
+   File& operator=(const File&);   ///< This is here to disable assignment.
+
+public:
+   File();                     ///< Default constructor
+   virtual ~File();            ///< Destructor
+
+   /// Opens a file for access using the specified AccessMode
+   ///
+   /// @returns The status of the file
+   Status open(const char *filename, const AccessMode openMode);
+
+   /// Gets the current position in the file
+   ///
+   /// This is in bytes from the beginning of the file.
+   U32 getPosition() const;
+
+   /// Sets the current position in the file.
+   ///
+   /// You can set either a relative or absolute position to go to in the file.
+   ///
+   /// @code
+   /// File *foo;
+   ///
+   /// ... set up file ...
+   ///
+   /// // Go to byte 32 in the file...
+   /// foo->setPosition(32);
+   ///
+   /// // Now skip back 20 bytes...
+   /// foo->setPosition(-20, false);
+   ///
+   /// // And forward 17...
+   /// foo->setPosition(17, false);
+   /// @endcode
+   ///
+   /// @returns The status of the file
+   Status setPosition(S32 position, bool absolutePos = true);
+
+   /// Returns the size of the file
+   U32 getSize() const;
+
+   /// Make sure everything that's supposed to be written to the file gets written.
+   ///
+   /// @returns The status of the file.
+   Status flush();
+
+   /// Closes the file
+   ///
+   /// @returns The status of the file.
+   Status close();
+
+   /// Gets the status of the file
+   Status getStatus() const;
+
+   /// Reads "size" bytes from the file, and dumps data into "dst".
+   /// The number of actual bytes read is returned in bytesRead
+   /// @returns The status of the file
+   Status read(U32 size, char *dst, U32 *bytesRead = NULL);
+
+   /// Writes "size" bytes into the file from the pointer "src".
+   /// The number of actual bytes written is returned in bytesWritten
+   /// @returns The status of the file
+   Status write(U32 size, const char *src, U32 *bytesWritten = NULL);
+
+   /// Returns whether or not this file is capable of the given function.
+   bool hasCapability(Capability cap) const;
+
+   const void* getHandle() { return handle; }
+
+protected:
+   Status setStatus();                 ///< Called after error encountered.
+   Status setStatus(Status status);    ///< Setter for the current status.
+};
+
+#endif // _FILE_IO_H_