SceIoDirent.java

/*
This file is part of jpcsp.

Jpcsp is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Jpcsp is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Jpcsp.  If not, see <http://www.gnu.org/licenses/>.
 */
package jpcsp.HLE.kernel.types;

import jpcsp.Memory;
import jpcsp.HLE.Modules;
import jpcsp.util.Utilities;

/** http://psp.jim.sh/pspsdk-doc/structSceIoDirent.html */
public class SceIoDirent extends pspAbstractMemoryMappedStructure {
    public SceIoStat stat;
    public String filename;
    public int extendedInfoAddr; // This field is a pointer to user data and only used by the MemoryStick driver.
    public int dummy; // Always 0.
    private boolean useExtendedInfo;

    public SceIoDirent(SceIoStat stat, String filename) {
        this.stat = stat;
        this.filename = filename;
    }

	@Override
	protected void read() {
		stat = new SceIoStat();
		read(stat);
		filename = readStringNZ(256);
		extendedInfoAddr = read32();
		dummy = read32();
	}

	// Convert a "long" file name into a 8.3 file name.
	// TODO Implement correct 8.3 truncation.
	private static String convertFileNameTo83(String fileName) {
		if (fileName == null) {
			return null;
		}

		// Special character '+' is turned into '_'
		fileName = fileName.replace("+", "_");
		// File name is upper-cased
		fileName = fileName.toUpperCase();

		// Split into the name and extension parts
		int lastDot = fileName.lastIndexOf(".");
		String name;
		String ext;
		if (lastDot < 0) {
			name = fileName;
			ext = "";
		} else {
			name = fileName.substring(0, lastDot);
			ext = fileName.substring(lastDot + 1);
		}

		// All dots in name part are dropped
		name = name.replace(".", "");

		// The file extension is truncated to 3 characters
		if (ext.length() > 3) {
			ext = ext.substring(0, 3);
		}

		// The name is truncated to 6 characters (if longer than 8 characters)
		// followed by "~1"
		if (name.length() > 8) {
			name = name.substring(0, 6) + "~1";
		}

		// TODO Check if there is a name collision with "~1"

		return name + "." + ext;
	}

	@Override
	protected void write() {
		write(stat);
		writeStringNZ(256, filename);
		// NOTE: Do not overwrite the reserved field.
		// Tests confirm that sceIoDread only writes the stat and filename.

		if (useExtendedInfo) {
			if (extendedInfoAddr == 0) {
				extendedInfoAddr = read32();
			}
			if (Memory.isAddressGood(extendedInfoAddr)) {
				if (Modules.SysMemUserForUserModule.hleKernelGetCompiledSdkVersion() <= 0x0307FFFF) {
					// "reserved" is pointing to an area of unknown size
					// - [0..12] "8.3" file name (null-terminated)
					// - [13..???] long file name (null-terminated)
		            Utilities.writeStringNZ(mem, extendedInfoAddr + 0, 13, convertFileNameTo83(filename));
		            Utilities.writeStringZ(mem, extendedInfoAddr + 13, filename);
				} else {
					// "reserved" is pointing to an area of total size 1044
					// - [0..3] size of area
					// - [4..19] "8.3" file name (null-terminated)
					// - [20..???] long file name (null-terminated)
					int size = mem.read32(extendedInfoAddr);
					if (size == 1044) {
						Utilities.writeStringNZ(mem, extendedInfoAddr + 4, 13, convertFileNameTo83(filename));
						Utilities.writeStringNZ(mem, extendedInfoAddr + 20, 1024, filename);
					}
				}
			}
		}
	}

	public void setUseExtendedInfo(boolean useExtendedInfo) {
		this.useExtendedInfo = useExtendedInfo;
	}

	@Override
	public int sizeof() {
		return SceIoStat.SIZEOF + 256 + 8;
	}
}