#include "chess.h"
#include "data.h"
/* last modified 05/08/14 */
/*
*******************************************************************************
* *
* SetBoard() is used to set up the board in any position desired. It uses *
* a forsythe-like string of characters to describe the board position. *
* *
* The standard piece codes p,n,b,r,q,k are used to denote the type of piece *
* on a square, upper/lower case are used to indicate the side (program/ *
* opponent) of the piece. *
* *
* The pieces are entered with square a8 first, then b8, ... until the full *
* 8th rank is completed. A "/" terminates that rank. This is repeated for *
* each of the 8 ranks, with the last (1st) rank not needing a terminating *
* "/". For empty squares, a number between 1 and 8 can be used to indicate *
* the number of adjacent empty squares. *
* *
* That board description must be followed by a "b" or "w" to indicate which *
* side is on move. *
* *
* Next, up to 4 characters are used to indicate which side can castle and *
* to which side. An uppercase K means white can castle kingside, while a *
* lowercase q means black can castle queenside. *
* *
* Finally, if there is an enpassant capture possible (the last move was a *
* double pawn move and there was an enemy pawn that could capture it. The *
* square is the square the capturing pawn ends up on. *
* *
* K2R/PPP////q/5ppp/7k/ b - - *
* *
* this assumes that k represents a white king and -q represents a black *
* queen. *
* *
* k * * r * * * * *
* p p p * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* -q * * * * * * * *
* * * * * * -p -p -p *
* * * * * * * * -k *
* *
*******************************************************************************
*/
void SetBoard(TREE * tree, int nargs, char *args[], int special) {
int twtm, i, match, num, pos, square, tboard[64];
int bcastle, ep, wcastle, error = 0, whichsq;
char input[80];
static const char bdinfo[] =
{ 'k', 'q', 'r', 'b', 'n', 'p', '*', 'P', 'N', 'B',
'R', 'Q', 'K', '*', '1', '2', '3', '4',
'5', '6', '7', '8', '/'
};
static const char status[13] =
{ 'K', 'Q', 'k', 'q', 'a', 'b', 'c', 'd', 'e', 'f', 'g',
'h', ' '
};
static const int firstsq[8] = { 56, 48, 40, 32, 24, 16, 8, 0 };
if (special)
strcpy(input
, initial_position
); else
for (i = 0; i < 64; i++)
tboard[i] = 0;
/*
************************************************************
* *
* Scan the input string searching for pieces, numbers *
* [empty squares], slashes [end-of-rank] and a blank *
* [end of board, start of castle status]. *
* *
************************************************************
*/
whichsq = 0;
square = firstsq[whichsq];
num = 0;
for (pos
= 0; pos
< (int) strlen(args
[0]); pos
++) { for (match = 0; match < 23 && args[0][pos] != bdinfo[match]; match++);
if (match > 22)
break;
/*
"/" -> end of this rank.
*/
else if (match == 22) {
num = 0;
if (whichsq > 6)
break;
square = firstsq[++whichsq];
}
/*
"1-8" -> empty squares.
*/
else if (match >= 14) {
num += match - 13;
square += match - 13;
if (num > 8) {
printf("more than 8 squares on one rank\n"); error = 1;
break;
}
continue;
}
/*
piece codes.
*/
else {
if (++num > 8) {
printf("more than 8 squares on one rank\n"); error = 1;
break;
}
tboard[square++] = match - 6;
}
}
/*
************************************************************
* *
* Now extract (a) side to move [w/b], (b) castle status *
* [KkQq for white/black king-side ok, white/black queen- *
* side ok], (c) enpassant target square. *
* *
************************************************************
*/
twtm = 0;
ep = 0;
wcastle = 0;
bcastle = 0;
/*
************************************************************
* *
* Side to move. *
* *
************************************************************
*/
if (args[1][0] == 'w')
twtm = 1;
else if (args[1][0] == 'b')
twtm = 0;
else {
printf("side to move is bad\n"); error = 1;
}
/*
************************************************************
* *
* Castling/enpassant status. *
* *
************************************************************
*/
if (nargs
> 2 && strlen(args
[2])) { for (pos
= 0; pos
< (int) strlen(args
[2]); pos
++) { for (match = 0; (match < 13) && (args[2][pos] != status[match]);
match++);
if (match == 0)
wcastle += 1;
else if (match == 1)
wcastle += 2;
else if (match == 2)
bcastle += 1;
else if (match == 3)
bcastle += 2;
else if (args[2][0] != '-') {
printf("castling status is bad.\n"); error = 1;
}
}
}
}
if (nargs
> 3 && strlen(args
[3])) { if (args[3][0] >= 'a' && args[3][0] <= 'h' && args[3][1] > '0' &&
args[3][1] < '9') {
ep = (args[3][1] - '1') * 8 + args[3][0] - 'a';
} else if (args[3][0] != '-') {
printf("enpassant status is bad.\n"); error = 1;
}
}
}
for (i = 0; i < 64; i++)
PcOnSq(i) = tboard[i];
Castle(0, white) = wcastle;
Castle(0, black) = bcastle;
EnPassant(0) = 0;
if (ep) {
do {
if (twtm && Rank(ep) == RANK6 && PcOnSq(ep - 8) == -pawn) {
if (File(ep) != 7 && PcOnSq(ep - 7) == pawn)
break;
if (File(ep) != 0 && PcOnSq(ep - 9) == pawn)
break;
} else if (!twtm && Rank(ep) == RANK3 && PcOnSq(ep + 8) == pawn) {
if (File(ep) != 0 && PcOnSq(ep + 7) == -pawn)
break;
if (File(ep) != 7 && PcOnSq(ep + 9) == -pawn)
break;
} else {
ep = 0;
}
if (!ep) {
printf("enpassant status is bad.\n"); ep = 0;
error = 1;
}
} while (0);
EnPassant(0) = ep;
}
/*
************************************************************
* *
* Now check the castling status status to make sure that *
* the board is in a state that matches. *
* *
************************************************************
*/
if (((Castle(0, white) & 2) && (PcOnSq(A1) != rook))
|| ((Castle(0, white) & 1) && (PcOnSq(H1) != rook))
|| ((Castle(0, black) & 2) && (PcOnSq(A8) != -rook))
|| ((Castle(0, black) & 1) && (PcOnSq(H8) != -rook))) {
printf("ERROR-- castling status does not match board position\n"); error = 1;
}
/*
************************************************************
* *
* Now set the bitboards so that error tests can be done. *
* *
************************************************************
*/
SetChessBitBoards(tree);
/*
************************************************************
* *
* Now check the position for a sane position, which means *
* no more than 8 pawns, no more than 10 knights, bishops *
* or rooks, no more than 9 queens, no pawns on 1st or 8th *
* rank, etc. *
* *
************************************************************
*/
game_wtm = twtm;
error += InvalidPosition(tree);
if (!error) {
if (log_file)
DisplayChessBoard(log_file, tree->position);
rep_index = 0;
tree->rep_list[0] = HashKey;
Reversible(0) = 0;
if (!special) {
last_mate_score = 0;
InitializeKillers();
last_pv.pathd = 0;
last_pv.pathl = 0;
tree->pv[0].pathd = 0;
tree->pv[0].pathl = 0;
moves_out_of_book = 0;
}
} else {
if (special)
Print(4095, "bad string = \"%s\"\n", initial_position);
else
Print(4095, "bad string = \"%s\"\n", args[0]);
InitializeChessBoard(tree);
Print(4095, "Illegal position, using normal initial chess position\n");
}
}