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1 /* |
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2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. |
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3 * |
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4 * Copyright 2014 Mike Becker. All rights reserved. |
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5 * |
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6 * Redistribution and use in source and binary forms, with or without |
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7 * modification, are permitted provided that the following conditions are met: |
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8 * |
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9 * 1. Redistributions of source code must retain the above copyright |
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10 * notice, this list of conditions and the following disclaimer. |
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11 * |
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12 * 2. Redistributions in binary form must reproduce the above copyright |
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13 * notice, this list of conditions and the following disclaimer in the |
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14 * documentation and/or other materials provided with the distribution. |
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15 * |
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16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
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17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
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20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
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21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
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22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
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23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
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24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
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25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
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26 * POSSIBILITY OF SUCH DAMAGE. |
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27 * |
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28 */ |
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29 |
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30 #include "rules.h" |
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31 #include "chess.h" |
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32 #include <string.h> |
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33 #include <stdlib.h> |
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34 #include <sys/time.h> |
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35 |
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36 static GameState gamestate_copy_sim(GameState *gamestate) { |
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37 GameState simulation = *gamestate; |
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38 if (simulation.lastmove) { |
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39 MoveList *lastmovecopy = malloc(sizeof(MoveList)); |
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40 *lastmovecopy = *(simulation.lastmove); |
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41 simulation.movelist = simulation.lastmove = lastmovecopy; |
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42 } |
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43 |
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44 return simulation; |
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45 } |
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46 |
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47 void gamestate_init(GameState *gamestate) { |
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48 memset(gamestate, 0, sizeof(GameState)); |
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49 |
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50 Board initboard = { |
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51 {WROOK, WKNIGHT, WBISHOP, WQUEEN, WKING, WBISHOP, WKNIGHT, WROOK}, |
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52 {WPAWN, WPAWN, WPAWN, WPAWN, WPAWN, WPAWN, WPAWN, WPAWN}, |
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53 {0, 0, 0, 0, 0, 0, 0, 0}, |
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54 {0, 0, 0, 0, 0, 0, 0, 0}, |
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55 {0, 0, 0, 0, 0, 0, 0, 0}, |
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56 {0, 0, 0, 0, 0, 0, 0, 0}, |
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57 {BPAWN, BPAWN, BPAWN, BPAWN, BPAWN, BPAWN, BPAWN, BPAWN}, |
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58 {BROOK, BKNIGHT, BBISHOP, BQUEEN, BKING, BBISHOP, BKNIGHT, BROOK} |
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59 }; |
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60 memcpy(gamestate->board, initboard, sizeof(Board)); |
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61 } |
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62 |
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63 void gamestate_cleanup(GameState *gamestate) { |
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64 MoveList *elem; |
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65 elem = gamestate->movelist; |
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66 while (elem) { |
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67 MoveList *cur = elem; |
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68 elem = elem->next; |
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69 free(cur); |
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70 }; |
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71 } |
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72 |
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73 /* MUST be called IMMEDIATLY after applying a move to work correctly */ |
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74 static void format_move(GameState *gamestate, Move *move) { |
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75 char *string = move->string; |
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76 |
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77 /* at least 8 characters should be available, wipe them out */ |
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78 memset(string, 0, 8); |
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79 |
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80 /* special formats for castling */ |
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81 if ((move->piece&PIECE_MASK) == KING && |
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82 abs(move->tofile-move->fromfile) == 2) { |
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83 if (move->tofile==fileidx('c')) { |
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84 memcpy(string, "O-O-O", 5); |
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85 } else { |
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86 memcpy(string, "O-O", 3); |
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87 } |
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88 } |
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89 |
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90 /* start by notating the piece character */ |
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91 string[0] = getpiecechr(move->piece); |
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92 int idx = string[0] ? 1 : 0; |
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93 |
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94 /* find out how many source information we do need */ |
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95 uint8_t piece = move->piece & PIECE_MASK; |
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96 if (piece == PAWN) { |
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97 if (move->capture) { |
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98 string[idx++] = filechr(move->fromfile); |
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99 } |
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100 } else if (piece != KING) { |
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101 Move threats[16]; |
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102 uint8_t threatcount; |
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103 get_real_threats(gamestate, move->torow, move->tofile, |
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104 move->piece&COLOR_MASK, threats, &threatcount); |
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105 if (threatcount > 1) { |
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106 int ambrows = 0, ambfiles = 0; |
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107 for (uint8_t i = 0 ; i < threatcount ; i++) { |
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108 if (threats[i].fromrow == move->fromrow) { |
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109 ambrows++; |
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110 } |
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111 if (threats[i].fromfile == move->fromfile) { |
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112 ambfiles++; |
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113 } |
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114 } |
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115 /* ambiguous row, name file */ |
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116 if (ambrows > 1) { |
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117 string[idx++] = filechr(move->fromfile); |
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118 } |
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119 /* ambiguous file, name row */ |
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120 if (ambfiles > 1) { |
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121 string[idx++] = filechr(move->fromrow); |
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122 } |
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123 } |
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124 } |
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125 |
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126 /* capturing? */ |
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127 if (move->capture) { |
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128 string[idx++] = 'x'; |
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129 } |
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130 |
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131 /* destination */ |
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132 string[idx++] = filechr(move->tofile); |
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133 string[idx++] = rowchr(move->torow); |
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134 |
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135 /* promotion? */ |
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136 if (move->promotion) { |
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137 string[idx++] = '='; |
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138 string[idx++] = getpiecechr(move->promotion); |
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139 } |
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140 |
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141 /* check? */ |
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142 if (move->check) { |
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143 /* works only, if this function is called when applying the move */ |
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144 string[idx++] = gamestate->checkmate?'#':'+'; |
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145 } |
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146 } |
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147 |
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148 static void addmove(GameState* gamestate, Move *move) { |
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149 MoveList *elem = malloc(sizeof(MoveList)); |
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150 elem->next = NULL; |
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151 elem->move = *move; |
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152 |
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153 struct timeval curtimestamp; |
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154 gettimeofday(&curtimestamp, NULL); |
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155 elem->move.timestamp.tv_sec = curtimestamp.tv_sec; |
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156 elem->move.timestamp.tv_usec = curtimestamp.tv_usec; |
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157 |
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158 if (gamestate->lastmove) { |
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159 struct movetimeval *lasttstamp = &(gamestate->lastmove->move.timestamp); |
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160 uint64_t sec = curtimestamp.tv_sec - lasttstamp->tv_sec; |
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161 suseconds_t micros; |
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162 if (curtimestamp.tv_usec < lasttstamp->tv_usec) { |
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163 micros = 1e6L-(lasttstamp->tv_usec - curtimestamp.tv_usec); |
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164 sec--; |
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165 } else { |
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166 micros = curtimestamp.tv_usec - lasttstamp->tv_usec; |
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167 } |
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168 |
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169 elem->move.movetime.tv_sec = sec; |
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170 elem->move.movetime.tv_usec = micros; |
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171 |
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172 gamestate->lastmove->next = elem; |
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173 gamestate->lastmove = elem; |
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174 } else { |
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175 elem->move.movetime.tv_usec = 0; |
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176 elem->move.movetime.tv_sec = 0; |
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177 gamestate->movelist = gamestate->lastmove = elem; |
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178 } |
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179 } |
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180 |
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181 char getpiecechr(uint8_t piece) { |
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182 switch (piece & PIECE_MASK) { |
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183 case ROOK: return 'R'; |
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184 case KNIGHT: return 'N'; |
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185 case BISHOP: return 'B'; |
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186 case QUEEN: return 'Q'; |
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187 case KING: return 'K'; |
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188 default: return '\0'; |
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189 } |
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190 } |
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191 |
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192 uint8_t getpiece(char c) { |
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193 switch (c) { |
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194 case 'R': return ROOK; |
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195 case 'N': return KNIGHT; |
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196 case 'B': return BISHOP; |
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197 case 'Q': return QUEEN; |
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198 case 'K': return KING; |
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199 default: return 0; |
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200 } |
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201 } |
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202 |
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203 static void apply_move_impl(GameState *gamestate, Move *move, _Bool simulate) { |
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204 uint8_t piece = move->piece & PIECE_MASK; |
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205 uint8_t color = move->piece & COLOR_MASK; |
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206 |
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207 /* en passant capture */ |
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208 if (move->capture && piece == PAWN && |
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209 mdst(gamestate->board, move) == 0) { |
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210 gamestate->board[move->fromrow][move->tofile] = 0; |
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211 } |
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212 |
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213 /* remove old en passant threats */ |
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214 for (uint8_t file = 0 ; file < 8 ; file++) { |
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215 gamestate->board[3][file] &= ~ENPASSANT_THREAT; |
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216 gamestate->board[4][file] &= ~ENPASSANT_THREAT; |
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217 } |
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218 |
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219 /* add new en passant threat */ |
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220 if (piece == PAWN && ( |
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221 (move->fromrow == 1 && move->torow == 3) || |
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222 (move->fromrow == 6 && move->torow == 4))) { |
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223 move->piece |= ENPASSANT_THREAT; |
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224 } |
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225 |
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226 /* move (and maybe capture or promote) */ |
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227 msrc(gamestate->board, move) = 0; |
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228 if (move->promotion) { |
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229 mdst(gamestate->board, move) = move->promotion; |
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230 } else { |
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231 mdst(gamestate->board, move) = move->piece; |
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232 } |
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233 |
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234 /* castling */ |
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235 if (piece == KING && move->fromfile == fileidx('e')) { |
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236 |
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237 if (move->tofile == fileidx('g')) { |
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238 gamestate->board[move->torow][fileidx('h')] = 0; |
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239 gamestate->board[move->torow][fileidx('f')] = color|ROOK; |
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240 } else if (move->tofile == fileidx('c')) { |
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241 gamestate->board[move->torow][fileidx('a')] = 0; |
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242 gamestate->board[move->torow][fileidx('d')] = color|ROOK; |
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243 } |
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244 } |
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245 |
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246 if (!simulate) { |
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247 if (!move->string[0]) { |
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248 format_move(gamestate, move); |
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249 } |
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250 } |
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251 /* add move, even in simulation (checkmate test needs it) */ |
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252 addmove(gamestate, move); |
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253 } |
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254 |
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255 void apply_move(GameState *gamestate, Move *move) { |
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256 apply_move_impl(gamestate, move, 0); |
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257 } |
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258 |
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259 static int validate_move_rules(GameState *gamestate, Move *move) { |
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260 /* validate indices (don't trust opponent) */ |
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261 if (!chkidx(move)) { |
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262 return INVALID_POSITION; |
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263 } |
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264 |
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265 /* must move */ |
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266 if (move->fromfile == move->tofile && move->fromrow == move->torow) { |
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267 return INVALID_MOVE_SYNTAX; |
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268 } |
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269 |
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270 /* does piece exist */ |
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271 if ((msrc(gamestate->board, move)&(PIECE_MASK|COLOR_MASK)) |
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272 != (move->piece&(PIECE_MASK|COLOR_MASK))) { |
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273 return INVALID_POSITION; |
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274 } |
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275 |
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276 /* can't capture own pieces */ |
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277 if ((mdst(gamestate->board, move) & COLOR_MASK) |
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278 == (move->piece & COLOR_MASK)) { |
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279 return RULES_VIOLATED; |
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280 } |
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281 |
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282 /* must capture, if and only if destination is occupied */ |
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283 if ((mdst(gamestate->board, move) == 0 && move->capture) || |
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284 (mdst(gamestate->board, move) != 0 && !move->capture)) { |
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285 return INVALID_MOVE_SYNTAX; |
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286 } |
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287 |
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288 /* validate individual rules */ |
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289 _Bool chkrules; |
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290 switch (move->piece & PIECE_MASK) { |
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291 case PAWN: |
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292 chkrules = pawn_chkrules(gamestate, move) && |
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293 !pawn_isblocked(gamestate, move); |
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294 break; |
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295 case ROOK: |
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296 chkrules = rook_chkrules(move) && |
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297 !rook_isblocked(gamestate, move); |
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298 break; |
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299 case KNIGHT: |
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300 chkrules = knight_chkrules(move); /* knight is never blocked */ |
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301 break; |
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302 case BISHOP: |
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303 chkrules = bishop_chkrules(move) && |
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304 !bishop_isblocked(gamestate, move); |
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305 break; |
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306 case QUEEN: |
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307 chkrules = queen_chkrules(move) && |
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308 !queen_isblocked(gamestate, move); |
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309 break; |
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310 case KING: |
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311 chkrules = king_chkrules(gamestate, move) && |
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312 !king_isblocked(gamestate, move); |
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313 break; |
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314 default: |
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315 return INVALID_MOVE_SYNTAX; |
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316 } |
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317 |
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318 return chkrules ? VALID_MOVE_SEMANTICS : RULES_VIOLATED; |
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319 } |
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320 |
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321 int validate_move(GameState *gamestate, Move *move) { |
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322 |
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323 int result = validate_move_rules(gamestate, move); |
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324 |
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325 /* cancel processing to save resources */ |
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326 if (result != VALID_MOVE_SEMANTICS) { |
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327 return result; |
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328 } |
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329 |
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330 /* find kings for check validation */ |
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331 uint8_t piececolor = (move->piece & COLOR_MASK); |
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332 |
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333 uint8_t mykingfile = 0, mykingrow = 0, opkingfile = 0, opkingrow = 0; |
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334 for (uint8_t row = 0 ; row < 8 ; row++) { |
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335 for (uint8_t file = 0 ; file < 8 ; file++) { |
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336 if (gamestate->board[row][file] == |
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337 (piececolor == WHITE?WKING:BKING)) { |
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338 mykingfile = file; |
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339 mykingrow = row; |
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340 } else if (gamestate->board[row][file] == |
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341 (piececolor == WHITE?BKING:WKING)) { |
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342 opkingfile = file; |
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343 opkingrow = row; |
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344 } |
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345 } |
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346 } |
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347 |
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348 /* simulate move for check validation */ |
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349 GameState simulation = gamestate_copy_sim(gamestate); |
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350 Move simmove = *move; |
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351 apply_move_impl(&simulation, &simmove, 1); |
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352 |
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353 /* don't move into or stay in check position */ |
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354 if (is_covered(&simulation, mykingrow, mykingfile, |
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355 opponent_color(piececolor))) { |
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356 |
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357 gamestate_cleanup(&simulation); |
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358 if ((move->piece & PIECE_MASK) == KING) { |
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359 return KING_MOVES_INTO_CHECK; |
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360 } else { |
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361 /* last move is always not null in this case */ |
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362 return gamestate->lastmove->move.check ? |
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363 KING_IN_CHECK : PIECE_PINNED; |
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364 } |
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365 } |
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366 |
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367 /* correct check and checkmate flags (move is still valid) */ |
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368 Move threats[16]; |
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369 uint8_t threatcount; |
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370 move->check = get_threats(&simulation, opkingrow, opkingfile, |
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371 piececolor, threats, &threatcount); |
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372 |
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373 if (move->check) { |
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374 /* determine possible escape fields */ |
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375 _Bool canescape = 0; |
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376 for (int dr = -1 ; dr <= 1 && !canescape ; dr++) { |
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377 for (int df = -1 ; df <= 1 && !canescape ; df++) { |
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378 if (!(dr == 0 && df == 0) && |
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379 isidx(opkingrow + dr) && isidx(opkingfile + df)) { |
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380 |
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381 /* escape field neither blocked nor covered */ |
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382 if ((simulation.board[opkingrow + dr][opkingfile + df] |
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383 & COLOR_MASK) != opponent_color(piececolor)) { |
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384 canescape |= !is_covered(&simulation, |
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385 opkingrow + dr, opkingfile + df, piececolor); |
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386 } |
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387 } |
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388 } |
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389 } |
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390 /* can't escape, can he capture? */ |
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391 if (!canescape && threatcount == 1) { |
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392 canescape = is_attacked(&simulation, threats[0].fromrow, |
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393 threats[0].fromfile, opponent_color(piececolor)); |
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394 } |
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395 |
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396 /* can't capture, can he block? */ |
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397 if (!canescape && threatcount == 1) { |
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398 Move *threat = &(threats[0]); |
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399 uint8_t threatpiece = threat->piece & PIECE_MASK; |
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400 |
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401 /* knight, pawns and the king cannot be blocked */ |
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402 if (threatpiece == BISHOP || threatpiece == ROOK |
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403 || threatpiece == QUEEN) { |
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404 if (threat->fromrow == threat->torow) { |
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405 /* rook aspect (on row) */ |
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406 int d = threat->tofile > threat->fromfile ? 1 : -1; |
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407 uint8_t file = threat->fromfile; |
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408 while (!canescape && file != threat->tofile - d) { |
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409 file += d; |
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410 canescape |= is_protected(&simulation, |
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411 threat->torow, file, opponent_color(piececolor)); |
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412 } |
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413 } else if (threat->fromfile == threat->tofile) { |
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414 /* rook aspect (on file) */ |
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415 int d = threat->torow > threat->fromrow ? 1 : -1; |
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416 uint8_t row = threat->fromrow; |
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417 while (!canescape && row != threat->torow - d) { |
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418 row += d; |
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419 canescape |= is_protected(&simulation, |
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420 row, threat->tofile, opponent_color(piececolor)); |
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421 } |
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422 } else { |
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423 /* bishop aspect */ |
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424 int dr = threat->torow > threat->fromrow ? 1 : -1; |
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425 int df = threat->tofile > threat->fromfile ? 1 : -1; |
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426 |
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427 uint8_t row = threat->fromrow; |
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428 uint8_t file = threat->fromfile; |
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429 while (!canescape && file != threat->tofile - df |
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430 && row != threat->torow - dr) { |
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431 row += dr; |
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432 file += df; |
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433 canescape |= is_protected(&simulation, row, file, |
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434 opponent_color(piececolor)); |
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435 } |
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436 } |
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437 } |
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438 } |
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439 |
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440 if (!canescape) { |
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441 gamestate->checkmate = 1; |
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442 } |
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443 } |
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444 |
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445 gamestate_cleanup(&simulation); |
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446 |
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447 return VALID_MOVE_SEMANTICS; |
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448 } |
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449 |
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450 _Bool get_threats(GameState *gamestate, uint8_t row, uint8_t file, |
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451 uint8_t color, Move *threats, uint8_t *threatcount) { |
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452 Move candidates[32]; |
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453 int candidatecount = 0; |
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454 for (uint8_t r = 0 ; r < 8 ; r++) { |
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455 for (uint8_t f = 0 ; f < 8 ; f++) { |
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456 if ((gamestate->board[r][f] & COLOR_MASK) == color) { |
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457 // non-capturing move |
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458 memset(&(candidates[candidatecount]), 0, sizeof(Move)); |
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459 candidates[candidatecount].piece = gamestate->board[r][f]; |
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460 candidates[candidatecount].fromrow = r; |
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461 candidates[candidatecount].fromfile = f; |
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462 candidates[candidatecount].torow = row; |
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463 candidates[candidatecount].tofile = file; |
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464 candidatecount++; |
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465 |
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466 // capturing move |
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467 memcpy(&(candidates[candidatecount]), |
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468 &(candidates[candidatecount-1]), sizeof(Move)); |
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469 candidates[candidatecount].capture = 1; |
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470 candidatecount++; |
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471 } |
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472 } |
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473 } |
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474 |
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475 if (threatcount) { |
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476 *threatcount = 0; |
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477 } |
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478 |
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479 |
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480 _Bool result = 0; |
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481 |
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482 for (int i = 0 ; i < candidatecount ; i++) { |
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483 if (validate_move_rules(gamestate, &(candidates[i])) |
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484 == VALID_MOVE_SEMANTICS) { |
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485 result = 1; |
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486 if (threats && threatcount) { |
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487 threats[(*threatcount)++] = candidates[i]; |
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488 } |
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489 } |
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490 } |
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491 |
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492 return result; |
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493 } |
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494 |
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495 _Bool is_pinned(GameState *gamestate, Move *move) { |
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496 uint8_t color = move->piece & COLOR_MASK; |
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497 |
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498 uint8_t kingfile = 0, kingrow = 0; |
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499 for (uint8_t row = 0 ; row < 8 ; row++) { |
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500 for (uint8_t file = 0 ; file < 8 ; file++) { |
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501 if (gamestate->board[row][file] == (color|KING)) { |
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502 kingfile = file; |
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503 kingrow = row; |
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504 } |
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505 } |
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506 } |
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507 |
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508 GameState simulation = gamestate_copy_sim(gamestate); |
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509 Move simmove = *move; |
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510 apply_move(&simulation, &simmove); |
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511 _Bool covered = is_covered(&simulation, |
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512 kingrow, kingfile, opponent_color(color)); |
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513 gamestate_cleanup(&simulation); |
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514 |
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515 return covered; |
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516 } |
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517 |
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518 _Bool get_real_threats(GameState *gamestate, uint8_t row, uint8_t file, |
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519 uint8_t color, Move *threats, uint8_t *threatcount) { |
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520 |
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521 if (threatcount) { |
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522 *threatcount = 0; |
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523 } |
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524 |
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525 Move candidates[16]; |
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526 uint8_t candidatecount; |
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527 if (get_threats(gamestate, row, file, color, candidates, &candidatecount)) { |
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528 |
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529 _Bool result = 0; |
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530 uint8_t kingfile = 0, kingrow = 0; |
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531 for (uint8_t row = 0 ; row < 8 ; row++) { |
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532 for (uint8_t file = 0 ; file < 8 ; file++) { |
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533 if (gamestate->board[row][file] == (color|KING)) { |
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534 kingfile = file; |
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535 kingrow = row; |
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536 } |
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537 } |
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538 } |
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539 |
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540 for (uint8_t i = 0 ; i < candidatecount ; i++) { |
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541 GameState simulation = gamestate_copy_sim(gamestate); |
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542 Move simmove = candidates[i]; |
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543 apply_move(&simulation, &simmove); |
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544 if (!is_covered(&simulation, kingrow, kingfile, |
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545 opponent_color(color))) { |
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546 result = 1; |
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547 if (threats && threatcount) { |
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548 threats[(*threatcount)++] = candidates[i]; |
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549 } |
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550 } |
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551 } |
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552 |
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553 return result; |
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554 } else { |
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555 return 0; |
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556 } |
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557 } |
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558 |
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559 static int getlocation(GameState *gamestate, Move *move) { |
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560 |
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561 uint8_t color = move->piece & COLOR_MASK; |
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562 _Bool incheck = gamestate->lastmove?gamestate->lastmove->move.check:0; |
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563 |
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564 Move threats[16], *threat = NULL; |
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565 uint8_t threatcount; |
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566 |
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567 if (get_threats(gamestate, move->torow, move->tofile, color, |
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568 threats, &threatcount)) { |
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569 |
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570 int reason = INVALID_POSITION; |
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571 |
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572 // find threats for the specified position |
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573 for (uint8_t i = 0 ; i < threatcount ; i++) { |
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574 if ((threats[i].piece & (PIECE_MASK | COLOR_MASK)) |
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575 == move->piece && |
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576 (move->fromrow == POS_UNSPECIFIED || |
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577 move->fromrow == threats[i].fromrow) && |
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578 (move->fromfile == POS_UNSPECIFIED || |
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579 move->fromfile == threats[i].fromfile)) { |
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580 |
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581 if (threat) { |
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582 return AMBIGUOUS_MOVE; |
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583 } else { |
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584 // found threat is no real threat |
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585 if (is_pinned(gamestate, &(threats[i]))) { |
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586 reason = incheck?KING_IN_CHECK:PIECE_PINNED; |
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587 } else { |
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588 threat = &(threats[i]); |
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589 } |
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590 } |
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591 } |
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592 } |
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593 |
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594 // can't threaten specified position |
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595 if (!threat) { |
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596 return reason; |
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597 } |
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598 |
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599 memcpy(move, threat, sizeof(Move)); |
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600 return VALID_MOVE_SYNTAX; |
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601 } else { |
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602 return INVALID_POSITION; |
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603 } |
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604 } |
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605 |
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606 int eval_move(GameState *gamestate, char *mstr, Move *move, uint8_t color) { |
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607 memset(move, 0, sizeof(Move)); |
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608 move->fromfile = POS_UNSPECIFIED; |
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609 move->fromrow = POS_UNSPECIFIED; |
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610 |
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611 size_t len = strlen(mstr); |
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612 if (len < 1 || len > 6) { |
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613 return INVALID_MOVE_SYNTAX; |
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614 } |
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615 |
|
616 /* evaluate check/checkmate flags */ |
|
617 if (mstr[len-1] == '+') { |
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618 len--; mstr[len] = '\0'; |
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619 move->check = 1; |
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620 } else if (mstr[len-1] == '#') { |
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621 len--; mstr[len] = '\0'; |
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622 /* ignore - validation should set game state */ |
|
623 } |
|
624 |
|
625 /* evaluate promotion */ |
|
626 if (len > 3 && mstr[len-2] == '=') { |
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627 move->promotion = getpiece(mstr[len-1]); |
|
628 if (!move->promotion) { |
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629 return INVALID_MOVE_SYNTAX; |
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630 } else { |
|
631 move->promotion |= color; |
|
632 len -= 2; |
|
633 mstr[len] = 0; |
|
634 } |
|
635 } |
|
636 |
|
637 if (len == 2) { |
|
638 /* pawn move (e.g. "e4") */ |
|
639 move->piece = PAWN; |
|
640 move->tofile = fileidx(mstr[0]); |
|
641 move->torow = rowidx(mstr[1]); |
|
642 } else if (len == 3) { |
|
643 if (strcmp(mstr, "O-O") == 0) { |
|
644 /* king side castling */ |
|
645 move->piece = KING; |
|
646 move->fromfile = fileidx('e'); |
|
647 move->tofile = fileidx('g'); |
|
648 move->fromrow = move->torow = color == WHITE ? 0 : 7; |
|
649 } else { |
|
650 /* move (e.g. "Nf3") */ |
|
651 move->piece = getpiece(mstr[0]); |
|
652 move->tofile = fileidx(mstr[1]); |
|
653 move->torow = rowidx(mstr[2]); |
|
654 } |
|
655 } else if (len == 4) { |
|
656 move->piece = getpiece(mstr[0]); |
|
657 if (!move->piece) { |
|
658 move->piece = PAWN; |
|
659 move->fromfile = fileidx(mstr[0]); |
|
660 } |
|
661 if (mstr[1] == 'x') { |
|
662 /* capture (e.g. "Nxf3", "dxe5") */ |
|
663 move->capture = 1; |
|
664 } else { |
|
665 /* move (e.g. "Ndf3", "N2c3", "e2e4") */ |
|
666 if (isfile(mstr[1])) { |
|
667 move->fromfile = fileidx(mstr[1]); |
|
668 if (move->piece == PAWN) { |
|
669 move->piece = 0; |
|
670 } |
|
671 } else { |
|
672 move->fromrow = rowidx(mstr[1]); |
|
673 } |
|
674 } |
|
675 move->tofile = fileidx(mstr[2]); |
|
676 move->torow = rowidx(mstr[3]); |
|
677 } else if (len == 5) { |
|
678 if (strcmp(mstr, "O-O-O") == 0) { |
|
679 /* queen side castling "O-O-O" */ |
|
680 move->piece = KING; |
|
681 move->fromfile = fileidx('e'); |
|
682 move->tofile = fileidx('c'); |
|
683 move->fromrow = move->torow = color == WHITE ? 0 : 7; |
|
684 } else { |
|
685 move->piece = getpiece(mstr[0]); |
|
686 if (mstr[2] == 'x') { |
|
687 move->capture = 1; |
|
688 if (move->piece) { |
|
689 /* capture (e.g. "Ndxf3") */ |
|
690 move->fromfile = fileidx(mstr[1]); |
|
691 } else { |
|
692 /* long notation capture (e.g. "e5xf6") */ |
|
693 move->piece = PAWN; |
|
694 move->fromfile = fileidx(mstr[0]); |
|
695 move->fromrow = rowidx(mstr[1]); |
|
696 } |
|
697 } else { |
|
698 /* long notation move (e.g. "Nc5a4") */ |
|
699 move->fromfile = fileidx(mstr[1]); |
|
700 move->fromrow = rowidx(mstr[2]); |
|
701 } |
|
702 move->tofile = fileidx(mstr[3]); |
|
703 move->torow = rowidx(mstr[4]); |
|
704 } |
|
705 } else if (len == 6) { |
|
706 /* long notation capture (e.g. "Nc5xf3") */ |
|
707 if (mstr[3] == 'x') { |
|
708 move->capture = 1; |
|
709 move->piece = getpiece(mstr[0]); |
|
710 move->fromfile = fileidx(mstr[1]); |
|
711 move->fromrow = rowidx(mstr[2]); |
|
712 move->tofile = fileidx(mstr[4]); |
|
713 move->torow = rowidx(mstr[5]); |
|
714 } |
|
715 } |
|
716 |
|
717 |
|
718 if (move->piece) { |
|
719 if (move->piece == PAWN |
|
720 && move->torow == (color==WHITE?7:0) |
|
721 && !move->promotion) { |
|
722 return NEED_PROMOTION; |
|
723 } |
|
724 |
|
725 move->piece |= color; |
|
726 if (move->fromfile == POS_UNSPECIFIED |
|
727 || move->fromrow == POS_UNSPECIFIED) { |
|
728 return getlocation(gamestate, move); |
|
729 } else { |
|
730 return chkidx(move) ? VALID_MOVE_SYNTAX : INVALID_POSITION; |
|
731 } |
|
732 } else { |
|
733 return INVALID_MOVE_SYNTAX; |
|
734 } |
|
735 } |
|
736 |
|
737 _Bool is_protected(GameState *gamestate, uint8_t row, uint8_t file, |
|
738 uint8_t color) { |
|
739 |
|
740 Move threats[16]; |
|
741 uint8_t threatcount; |
|
742 if (get_real_threats(gamestate, row, file, color, threats, &threatcount)) { |
|
743 for (int i = 0 ; i < threatcount ; i++) { |
|
744 if (threats[i].piece != (color|KING)) { |
|
745 return 1; |
|
746 } |
|
747 } |
|
748 return 0; |
|
749 } else { |
|
750 return 0; |
|
751 } |
|
752 } |
|
753 |
|
754 uint16_t remaining_movetime(GameInfo *gameinfo, GameState *gamestate, |
|
755 uint8_t color) { |
|
756 if (!gameinfo->timecontrol) { |
|
757 return 0; |
|
758 } |
|
759 |
|
760 if (gamestate->movelist) { |
|
761 uint16_t time = gameinfo->time; |
|
762 suseconds_t micros = 0; |
|
763 |
|
764 MoveList *movelist = color == WHITE ? |
|
765 gamestate->movelist : gamestate->movelist->next; |
|
766 |
|
767 while (movelist) { |
|
768 time += gameinfo->addtime; |
|
769 |
|
770 struct movetimeval *movetime = &(movelist->move.movetime); |
|
771 if (movetime->tv_sec >= time) { |
|
772 return 0; |
|
773 } |
|
774 |
|
775 time -= movetime->tv_sec; |
|
776 micros += movetime->tv_usec; |
|
777 |
|
778 movelist = movelist->next ? movelist->next->next : NULL; |
|
779 } |
|
780 |
|
781 time_t sec; |
|
782 movelist = gamestate->lastmove; |
|
783 if ((movelist->move.piece & COLOR_MASK) != color) { |
|
784 struct movetimeval *lastmovetstamp = &(movelist->move.timestamp); |
|
785 struct timeval currenttstamp; |
|
786 gettimeofday(¤ttstamp, NULL); |
|
787 micros += currenttstamp.tv_usec - lastmovetstamp->tv_usec; |
|
788 sec = currenttstamp.tv_sec - lastmovetstamp->tv_sec; |
|
789 if (sec >= time) { |
|
790 return 0; |
|
791 } |
|
792 |
|
793 time -= sec; |
|
794 } |
|
795 |
|
796 sec = micros / 1e6L; |
|
797 |
|
798 if (sec >= time) { |
|
799 return 0; |
|
800 } |
|
801 |
|
802 time -= sec; |
|
803 |
|
804 return time; |
|
805 } else { |
|
806 return gameinfo->time; |
|
807 } |
|
808 } |