Fri, 28 Mar 2014 14:32:52 +0100
introduced status codes for get_location to produce detailed error messages + added knight rules
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2014 Mike Becker. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 *
28 */
30 #include "pawn.h"
31 #include "rules.h"
33 _Bool pawn_chkrules(Board board, Move *move) {
34 int8_t d = ((move->piece & COLOR_MASK) == WHITE ? -1 : 1);
35 if (move->capture) {
36 if (move->fromrow == move->torow + d && (
37 move->fromfile == move->tofile + 1 ||
38 move->fromfile == move->tofile - 1)) {
40 return mdst(board,move)
41 || (board[move->fromrow][move->tofile] & ENPASSANT_THREAT);
42 } else {
43 return FALSE;
44 }
45 } else {
46 if (move->fromfile == move->tofile) {
47 return (move->fromrow == move->torow + d) ||
48 (move->fromrow == (d < 0 ? 1 : 6) && /* advanced first move */
49 move->fromrow == move->torow + d*2);
50 } else {
51 return FALSE;
52 }
53 }
54 }
56 _Bool pawn_isblocked(Board board, Move *move) {
57 return mdst(board,move) && !move->capture;
58 }
60 int pawn_getlocation(Board board, Move *move) {
61 int8_t d = ((move->piece & COLOR_MASK) == WHITE ? -1 : 1);
63 if (move->fromfile == POS_UNSPECIFIED) {
64 move->fromfile = move->tofile;
65 }
66 move->fromrow = move->torow + d;
67 if (move->fromrow > 6) {
68 return INVALID_POSITION;
69 } else {
70 /* advanced first move */
71 if (move->fromrow == (d < 0 ? 2 : 5) &&
72 msrc(board,move) != move->piece) {
74 move->fromrow += d;
75 if (move->fromrow > 6) {
76 return INVALID_POSITION;
77 }
78 }
79 }
80 return VALID_MOVE_SYNTAX;
81 }