diff -r 6008840b859e -r 6a26114297a1 src/rules/knight.c
--- a/src/rules/knight.c	Sat Mar 29 16:53:58 2014 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,133 +0,0 @@
-/*
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
- *
- * Copyright 2014 Mike Becker. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *   1. Redistributions of source code must retain the above copyright
- *      notice, this list of conditions and the following disclaimer.
- *
- *   2. Redistributions in binary form must reproduce the above copyright
- *      notice, this list of conditions and the following disclaimer in the
- *      documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#include "knight.h"
-#include "rules.h"
-#include <math.h>
-
-_Bool knight_chkrules(Move *move) {
-    int dx = abs(move->fromfile - move->tofile);
-    int dy = abs(move->fromrow - move->torow);
-    
-    return (dx == 2 && dy == 1) || (dx == 1 && dy == 2);
-}
-
-static int knight_getloc_fixedrow(Board board, Move *move) {
-    int d = 3 - abs(move->fromrow - move->torow);
-    
-    if (d == 1 || d == 2) {
-        if (move->tofile < 6 &&
-            board[move->fromrow][move->tofile + d] == move->piece) {
-            if (move->fromfile == POS_UNSPECIFIED) {
-                move->fromfile = move->tofile + d;
-                return VALID_MOVE_SYNTAX;
-            } else {
-                return AMBIGUOUS_MOVE;
-            }
-        }
-        if (move->tofile > 1 &&
-            board[move->fromrow][move->tofile - d] == move->piece) {
-            if (move->fromfile == POS_UNSPECIFIED) {
-                move->fromfile = move->tofile - d;
-                return VALID_MOVE_SYNTAX;
-            } else {
-                return AMBIGUOUS_MOVE;
-            }
-        }
-    }
-    
-    return INVALID_POSITION;
-}
-
-static int knight_getloc_fixedfile(Board board, Move *move) {
-    int d = 3 - abs(move->fromfile - move->tofile);
-    
-    if (d == 1 || d == 2) {
-        if (move->torow < 6 &&
-            board[move->torow + d][move->fromfile] == move->piece) {
-            if (move->fromrow == POS_UNSPECIFIED) {
-                move->fromrow = move->torow + d;
-                return VALID_MOVE_SYNTAX;
-            } else {
-                return AMBIGUOUS_MOVE;
-            }
-        }
-        if (move->torow > 1 &&
-            board[move->torow - d][move->fromfile] == move->piece) {
-            if (move->fromrow == POS_UNSPECIFIED) {
-                move->fromrow = move->torow - d;
-                return VALID_MOVE_SYNTAX;
-            } else {
-                return AMBIGUOUS_MOVE;
-            }
-        }
-    }
-    
-    return INVALID_POSITION;
-}
-
-int knight_getlocation(Board board, Move *move) {
-    
-    if (move->fromfile != POS_UNSPECIFIED) {
-        return knight_getloc_fixedfile(board, move);
-    }
-    
-    if (move->fromrow != POS_UNSPECIFIED) {
-        return knight_getloc_fixedrow(board, move);
-    }
-    
-    for (int x = -2 ; x <= 2 ; x++) {
-        if (x == 0) {
-            continue;
-        }
-        for (int y = -2 ; y <= 2 ; y++) {
-            if (y == 0 || y == x) {
-                continue;
-            }
-            uint8_t cx = move->tofile + x;
-            uint8_t cy = move->torow + y;
-
-            if (isidx(cx) && isidx(cy) && board[cy][cx] == move->piece) {
-                if (move->fromfile == POS_UNSPECIFIED
-                    && move->fromrow == POS_UNSPECIFIED) {
-                    move->fromfile = cx;
-                    move->fromrow = cy;
-                } else {
-                    return AMBIGUOUS_MOVE;
-                }
-            }
-        }
-    }
-    
-    if (move->fromfile == POS_UNSPECIFIED || move->fromrow == POS_UNSPECIFIED) {
-        return INVALID_POSITION;
-    } else {
-        return VALID_MOVE_SYNTAX;
-    }
-}