Low level polyglot binary opening book support.

1 files changed, 430 insertions, 0 deletions

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+;;; chess-polyglot.el --- Polyglot book access for Emacs  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2014  Mario Lang
+
+;; Author: Mario Lang <mlang@delysid.org>
+;; Keywords: games
+
+;; This program 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.
+
+;; This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; 
+
+;;; Code:
+
+(eval-when-compile (require 'cl-lib))
+(require 'chess-ply)
+(require 'chess-pos)
+
+(defsubst chess-polyglot-read-octets (count)
+  (let ((val 0))
+    (dotimes (i count (progn (cl-assert (<= val most-positive-fixnum)) val))
+      (setq val (logior (lsh val 8)
+			(progn (forward-char 1) (preceding-char)))))))
+
+(defsubst chess-polyglot-read-key ()
+  (cons (chess-polyglot-read-octets 4) (chess-polyglot-read-octets 4)))
+
+(defun chess-polyglot-read-move ()
+  (let ((mask (chess-polyglot-read-octets 2)))
+    (pcase (let (r)
+	     (dotimes (i 5 r)
+	       (push (logand mask 7) r)
+	       (setq mask (ash mask -3))))
+      (`(,promotion ,from-rank ,from-file ,to-rank ,to-file)
+       (list (chess-rf-to-index (- 7 from-rank) from-file)
+	     (chess-rf-to-index (- 7 to-rank) to-file)
+	     (nth promotion '(nil ?N ?B ?R ?Q))
+	     (chess-polyglot-read-octets 2))))))
+
+(defun chess-polyglot-move-to-ply (position from to promotion weight)
+  "Convert a polyglot move for POSITION to a ply."
+  (cl-assert (vectorp position))
+  (cl-assert (integerp from))
+  (cl-assert (integerp to))
+  (cl-assert (memq promotion '(nil ?N ?B ?R ?Q)))
+  (cl-assert (integerp weight))
+  (let ((ply (apply #'chess-ply-create position nil
+		    (if (and (= from
+				(chess-pos-king-index
+				 position (chess-pos-side-to-move position)))
+			     (= (chess-index-rank from) (chess-index-rank to))
+			     (or (= (chess-index-file to) 0)
+				 (= (chess-index-file to) 7)))
+			(chess-ply-castling-changes
+			 position (= (chess-index-file to) 0))
+		      (nconc (list from to)
+			     (when promotion (list :promote promotion)))))))
+    (chess-ply-set-keyword ply :polyglot-book-weight weight)
+    ply))
+
+(defsubst chess-polyglot-skip-learn ()
+  (forward-char 4))
+
+(defun chess-polyglot-moves (key &optional low high)
+  (unless low (setq low 0))
+  (unless high (setq high (1- (/ (buffer-size) 16))))
+  (let ((mid (/ (+ low high) 2)))
+    (goto-char (1+ (* mid 16)))
+    (let ((mid-key (chess-polyglot-read-key)))
+      (cond
+       ((= low high)
+	(when (equal key mid-key)
+	  (chess-polyglot-read-move)))
+       ((< (car key) (car mid-key))
+	(chess-polyglot-moves key low mid))
+       ((> (car key) (car mid-key))
+	(chess-polyglot-moves key (1+ mid) high))
+       (t (cond
+	   ((< (cdr key) (cdr mid-key))
+	    (chess-polyglot-moves key low mid))
+	   ((> (cdr key) (cdr mid-key))
+	    (chess-polyglot-moves key (1+ mid) high))
+	   (t (when (> (point) 16) (forward-char -16))
+	      (while (progn (forward-char -8)
+			    (and (> (point) 16) (equal key (chess-polyglot-read-key))))
+		(forward-char -16))
+	      (forward-char 8)
+	      (let (moves)
+		(while (equal key (chess-polyglot-read-key))
+		  (setq moves (nconc moves (list (chess-polyglot-read-move))))
+		  (chess-polyglot-skip-learn))
+		moves))))))))
+
+(defconst chess-polyglot-zorbit-hashes
+  [(2637767806 . 863464769) (720845184 . 95069639) (1155203408 . 610415943)
+   (2618685246 . 1655139042) (1971536997 . 1218186377) (848342074 . 540017087)
+   (263957791 . 1627660921) (3896152207 . 4076560586) (226391645 . 1484086288)
+   (436746274 . 3467632685) (2516964848 . 3797861296) (3491888988 . 3510251221)
+   (1086189917 . 1248276018) (18044180 . 1876255637) (1572111136 . 1190386149)
+   (597658413 . 2146900428) (97624494 . 2243205793) (1738507407 . 1854916977)
+   (1950989311 . 2149575947) (2098318769 . 3283594736) (2194108574 . 2015279052)
+   (4079062812 . 2500884588) (856979699 . 2941369318) (1270058469 . 3877737539)
+   (2858720366 . 3170717948) (2378012835 . 1387254795) (2278688587 . 2178388503)
+   (435406673 . 3555273441) (3031118064 . 1655806655) (2063925420 . 1107589828)
+   (3376753832 . 436852829) (615148625 . 1302492416) (1285502018 . 1963045959)
+   (346460119 . 1016137793) (2803604355 . 1176288659) (55085973 . 2968618255)
+   (1669016372 . 4287873088) (164740250 . 1037634196) (896886403 . 883023163)
+   (1935551383 . 2764331555) (410153072 . 4055711755) (533441746 . 1505690343)
+   (3541084098 . 3466290517) (3214426080 . 4267541060) (2675233103 . 1951705124)
+   (1374411850 . 3115986997) (1552073989 . 3684348154) (4244110986 . 875606593)
+   (844343081 . 3115990494) (2356462440 . 135999605) (3116133511 . 377238503)
+   (2129956651 . 2197966368) (299173332 . 3276914047) (1701379241 . 745972291)
+   (1306570996 . 254977976) (2530644806 . 214138461) (1122123979 . 1667800879)
+   (1831591130 . 3801192033) (1116211970 . 920967505) (1594837592 . 2551651254)
+   (972591349 . 2046373768) (2479207924 . 1935030411) (1675376029 . 2367888248)
+   (3960916618 . 3935874422) (1398143232 . 3265801671) (133930885 . 1520005442)
+   (1351827834 . 2829577566) (2076951437 . 2723839804) (435980918 . 2364847828)
+   (1668970368 . 3738157273) (2185864314 . 3993911799) (2041407829 . 31969768)
+   (346864372 . 2004703094) (4047877822 . 3437142421) (3669961416 . 538399484)
+   (616810829 . 4190688246) (3144558884 . 4030272234) (216165387 . 2513010905)
+   (2761740594 . 3216997572) (3919406634 . 4096014649) (669429112 . 2434161727)
+   (2234904640 . 3111407601) (1421079802 . 1598085235) (1924213810 . 310373675)
+   (4002762044 . 2067865415) (2592451728 . 2586110625) (1890340057 . 4031717877)
+   (4189625662 . 2577429954) (2276713138 . 3049850801) (2741429688 . 3310307512)
+   (2924122950 . 3426712818) (421576781 . 1193704381) (2277442246 . 3030264553)
+   (153237420 . 595540057) (4278711886 . 4176286928) (2380848297 . 4030514510)
+   (2618700582 . 1303682185) (3018992701 . 185284845) (957243316 . 1291916363)
+   (1543415220 . 1898408169) (504378001 . 531073412) (2591337657 . 1692896435)
+   (1333852064 . 903543556) (1661259930 . 188168388) (561112646 . 2197961224)
+   (1536910315 . 2632972300) (1349168372 . 2307429186) (411152329 . 2745631190)
+   (1694697476 . 1081411140) (3755185459 . 2631660711) (4019355068 . 4027326706)
+   (2066937809 . 3761668332) (3120395808 . 3878773315) (94890149 . 2109283191)
+   (3045629038 . 358812277) (1249184265 . 3465901047) (3477490924 . 2308583306)
+   (4114113436 . 3875911716) (1014604031 . 1434513279) (3991324799 . 2222416029)
+   (2040431088 . 1539915569) (2253613964 . 4081224332) (2547464012 . 1611168627)
+   (2722521980 . 4281500978) (71289574 . 213969824) (2450408597 . 903689630)
+   (1894451515 . 364024012) (1939968537 . 374938813) (1447259295 . 3785468557)
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+   (3373793513 . 2411305257) (2156648078 . 1791034213) (3737413652 . 1534461430)
+   (468575139 . 2935304962) (1129551363 . 3603256834) (2861996892 . 1763494778)
+   (2826449619 . 2465197654) (1704209531 . 1014895022) (3738359347 . 3402630390)
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+   (4012836163 . 150381244) (2938127093 . 3428591704) (1208226490 . 3086335530)
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+   (4109399782 . 1596778224) (288855589 . 1954372339) (3169178148 . 2256716053)
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+   (1359190711 . 1898207171) (3229237120 . 3273634996) (3027167685 . 3863637628)
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+   (4154611160 . 1002664952) (3623154244 . 2349656961) (3646679180 . 3524329383)
+   (862933752 . 4282853607) (2806008282 . 3272780913) (2734037942 . 3828874677)
+   (1328176304 . 2137666995) (2278785213 . 2780788825) (381286368 . 1816476193)
+   (2074232908 . 2316293454) (4087773386 . 3651330956) (967884669 . 3728964514)
+   (4239349185 . 3213509668) (419231360 . 1463788948) (1275421624 . 2672384707)
+   (1088456595 . 436245261) (2365565249 . 783696577) (1758083333 . 845223583)
+   (2048846183 . 3530914274) (2635948261 . 124738415) (940630937 . 3069598626)
+   (839474029 . 1253439921) (902477345 . 165479306) (2836079689 . 2681188273)
+   (2007115168 . 2093139645) (1363041891 . 1282466609) (1130479818 . 1063857938)
+   (3644959908 . 1260430427) (1385135238 . 46497915) (1386975934 . 3110156681)
+   (2635987502 . 4233461619) (1915744629 . 4117939016) (487743653 . 285736599)
+   (2049219159 . 3960249250) (69242857 . 3908563670) (1511066720 . 1488527520)
+   (215590039 . 1703564952) (1459430344 . 4184955468) (676103291 . 2642967214)
+   (83799035 . 3182827979) (1949179493 . 476101251) (2593534694 . 1493478716)
+   (2283504289 . 995211746) (1349412676 . 3449243940) (2954378677 . 1878813305)
+   (249149717 . 3329151870) (1578231917 . 1483986052) (4135085182 . 890874990)
+   (461755528 . 3505523909) (3669622373 . 634949665) (219487622 . 2914465301)
+   (2825233742 . 3703631897) (2479105382 . 2935590907) (2582097898 . 3187672881)
+   (1221328648 . 1843341402) (2140891889 . 3958868911) (1482849818 . 345750049)
+   (751922730 . 3178831411) (3546542069 . 4036458902) (216179596 . 877293293)
+   (444615341 . 3117393729) (2424254530 . 494454238) (1344234989 . 3003337991)
+   (929188581 . 2760877801) (2507911009 . 1879899982) (980166547 . 1311840394)
+   (3566535507 . 1790747461) (143525013 . 2311336672) (4181962471 . 4273938872)
+   (1815842366 . 862009811) (911175674 . 1179575598) (3591335374 . 3694215714)
+   (1452686093 . 3393294272) (385158879 . 2447709103) (4011414929 . 1264623507)
+   (1448477120 . 911094312) (3971299641 . 2289992053) (3133647265 . 2234591563)
+   (3007628400 . 964409938) (1708345684 . 3673411261) (3031964479 . 2843021794)
+   (3022128657 . 2480338599) (118850112 . 473449293) (2048127371 . 3202109429)
+   (3158349745 . 382018770) (1505327237 . 3807570472) (2568424029 . 3272693060)
+   (1866609495 . 3888556537) (844703982 . 1852802964) (3504617058 . 682636099)
+   (1448882679 . 3733580327) (821387540 . 2215744532) (3631471417 . 311618895)
+   (2077838877 . 2383929020) (3352949096 . 1688694420) (2491080787 . 3998672444)
+   (3368630402 . 4182204255) (983299419 . 2837414346) (3651215291 . 1033373924)
+   (265429091 . 3988955082) (3019003608 . 2896212153) (2955948456 . 3025235588)
+   (903690197 . 2266253487) (3925215275 . 89402958) (3959093811 . 3609545561)
+   (2455088053 . 223552128) (3115011301 . 2133669107) (1765081558 . 673805649)
+   (3324795129 . 2111392191) (3443871631 . 432345706) (3152559950 . 3425427147)
+   (3699649406 . 672784944) (3129545774 . 7668664) (2747044893 . 173040075)
+   (3925243406 . 852328481) (164095314 . 3161868591) (2234471571 . 1302682825)
+   (2164784335 . 105893718) (159995093 . 536831360) (599199451 . 425051327)
+   (3274759746 . 1680930461) (1192619331 . 3903085578) (2832721114 . 3078660237)
+   (91404660 . 4030521531) (3044880024 . 1578375623) (3906596030 . 754177855)
+   (803516785 . 1894094672) (288455592 . 2030430096) (2143232492 . 2317305324)
+   (388352703 . 3406060288) (2521731420 . 3588403719) (1043041227 . 4028028525)
+   (3195290851 . 2468913324) (4166724431 . 3168683191) (1228226538 . 968516529)
+   (500177583 . 3444787306) (533367442 . 4252082053) (4236023256 . 657816314)
+   (413575568 . 3367198397) (3435884549 . 3334062733) (1004255532 . 1135705894)
+   (2859513268 . 4170618274) (3914086821 . 1251487871) (3080761716 . 3489067886)
+   (3571165255 . 699353261) (773372954 . 3648014952) (769693293 . 2939128604)
+   (3116440923 . 507748478) (1687629160 . 3739431776) (2489486648 . 3502376324)
+   (3686847158 . 2878383449) (3530767427 . 902211375) (2121652637 . 2493976397)
+   (1827477891 . 930064171) (2549918411 . 4029725732) (2071415163 . 844118802)
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+   (2190878435 . 2301466071) (2465915458 . 2448602097) (1675766804 . 2073834499)
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+
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+
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+  "Zorbit hashes.")
+
+(defun chess-polyglot-pos-to-key (position)
+  "Convert a POSITION to a polyglot zorbist hash, a `cons' of 32bit integers."
+  (cl-assert (vectorp position))
+  (let ((pieces '(?p ?P ?n ?N ?b ?B ?r ?R ?q ?Q ?k ?K))
+	(key (cons 0 0)))
+    (dotimes (rank 8)
+      (dotimes (file 8)
+	(let ((piece (cl-position (chess-pos-piece position (chess-rf-to-index
+							     rank file))
+				  pieces)))
+	  (when piece
+	    (let ((piece-key (aref chess-polyglot-zorbit-hashes
+				   (+ (* 64 piece) (* (- 7 rank) 8) file))))
+	      (setcar key (logxor (car key) (car piece-key)))
+	      (setcdr key (logxor (cdr key) (cdr piece-key))))))))
+    (let ((sides '(?K ?Q ?k ?q)))
+      (dolist (side sides)
+	(when (chess-pos-can-castle position side)
+	  (let ((castle-key (aref chess-polyglot-zorbit-hashes
+				  (+ 768 (cl-position side sides)))))
+	    (setcar key (logxor (car key) (car castle-key)))
+	    (setcdr key (logxor (cdr key) (cdr castle-key)))))))
+    (when (chess-pos-side-to-move position)
+      (let ((turn-key (aref chess-polyglot-zorbit-hashes 780)))
+	(setcar key (logxor (car key) (car turn-key)))
+	(setcdr key (logxor (cdr key) (cdr turn-key)))))
+    key))
+
+(defun chess-polyglot-book-open (file)
+  "Open a polyglot book file.
+Returns a buffer object which contains the binary data."
+  (when (file-exists-p file)
+    (with-current-buffer (get-buffer-create (concat " *chess-polyglot " file "*"))
+      (erase-buffer)
+      (set-buffer-multibyte nil)
+      (insert-file-contents-literally file)
+      (current-buffer))))
+
+(defun chess-polyglot-book-plies (book position)
+  "Return a list of plies found in BOOK for POSITION.
+The :polyglot-book-weight ply keyword is used to store move weights."
+  (cl-assert (bufferp book))
+  (cl-assert (vectorp position))
+  (let (plies)
+    (dolist (move
+	     (with-current-buffer book
+	       (chess-polyglot-moves (chess-polyglot-pos-to-key position)))
+	     plies)
+      (let ((ply (apply #'chess-polyglot-move-to-ply position move)))
+	(when ply
+	  (setq plies (nconc plies (list ply))))))))
+
+(defalias 'chess-polyglot-book-close 'kill-buffer
+  "Close a polyglot book.")
+
+(provide 'chess-polyglot)
+;;; chess-polyglot.el ends here