xwords/xwords4/common/movestak.c
2003-11-01 05:35:29 +00:00

351 lines
9.4 KiB
C

/* -*-mode: C; fill-column: 78; c-basic-offset: 4; -*- */
/*
* Copyright 2001 by Eric House (fixin@peak.org). All rights reserved.
*
* 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 2
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
//#include "modelp.h"
#include "mempool.h"
#include "xwstream.h"
#include "movestak.h"
#include "memstream.h"
#include "strutils.h"
#ifdef CPLUS
extern "C" {
#endif
struct StackCtxt {
VTableMgr* vtmgr;
XWStreamCtxt* data;
XWStreamPos top;
XWStreamPos cachedPos;
XP_U16 cacheNext;
XP_U16 nEntries;
XP_U16 highWaterMark;
MPSLOT
};
void
stack_init( StackCtxt* stack )
{
stack->nEntries = stack->highWaterMark = 0;
stack->top = START_OF_STREAM;
/* I see little point in freeing or shrinking stack->data. It'll get
shrunk to fit as soon as we serialize/deserialize anyway. */
} /* stack_init */
StackCtxt*
stack_make( MPFORMAL VTableMgr* vtmgr )
{
StackCtxt* result = (StackCtxt*)XP_MALLOC( mpool, sizeof( *result ) );
if ( !!result ) {
XP_MEMSET( result, 0, sizeof(*result) );
MPASSIGN(result->mpool, mpool);
result->vtmgr = vtmgr;
}
return result;
} /* stack_make */
void
stack_destroy( StackCtxt* stack )
{
if ( !!stack->data ) {
stream_destroy( stack->data );
}
XP_FREE( stack->mpool, stack );
} /* stack_destroy */
void
stack_loadFromStream( StackCtxt* stack, XWStreamCtxt* stream )
{
XP_U16 nBytes = stream_getU16( stream );
if ( nBytes > 0 ) {
stack->highWaterMark = stream_getU16( stream );
stack->nEntries = stream_getU16( stream );
stack->top = stream_getU32( stream );
stack->data = mem_stream_make( MPPARM(stack->mpool) stack->vtmgr,
NULL, 0,
(MemStreamCloseCallback)NULL );
stream_copyFromStream( stack->data, stream, nBytes );
} else {
XP_ASSERT( stack->nEntries == 0 );
XP_ASSERT( stack->top == 0 );
}
} /* stack_makeFromStream */
void
stack_writeToStream( StackCtxt* stack, XWStreamCtxt* stream )
{
XP_U16 nBytes = !!stack->data? stream_getSize( stack->data ): 0;
stream_putU16( stream, nBytes );
if ( nBytes > 0 ) {
stream_putU16( stream, stack->highWaterMark );
stream_putU16( stream, stack->nEntries );
stream_putU32( stream, stack->top );
stream_setPos( stack->data, START_OF_STREAM, POS_READ );
stream_copyFromStream( stream, stack->data, nBytes );
}
} /* stack_writeToStream */
static void
pushEntry( StackCtxt* stack, StackEntry* entry )
{
XP_U16 i;
XWStreamPos oldLoc;
XP_U16 nTiles = entry->u.move.moveInfo.nTiles;
XWStreamCtxt* stream = stack->data;
if ( !stream ) {
stream = mem_stream_make( MPPARM(stack->mpool) stack->vtmgr, NULL, 0,
(MemStreamCloseCallback)NULL );
stack->data = stream;
}
oldLoc = stream_setPos( stream, stack->top, POS_WRITE );
stream_putBits( stream, 2, entry->moveType );
stream_putBits( stream, 2, entry->playerNum );
switch( entry->moveType ) {
case MOVE_TYPE:
case PHONY_TYPE:
stream_putBits( stream, NTILES_NBITS, nTiles );
stream_putBits( stream, 5, entry->u.move.moveInfo.commonCoord );
stream_putBits( stream, 1, entry->u.move.moveInfo.isHorizontal );
for ( i = 0; i < nTiles; ++i ) {
stream_putBits( stream, 5,
entry->u.move.moveInfo.tiles[i].varCoord );
stream_putBits( stream, 6, entry->u.move.moveInfo.tiles[i].tile );
}
if ( entry->moveType == MOVE_TYPE ) {
traySetToStream( stream, &entry->u.move.newTiles );
}
break;
case ASSIGN_TYPE:
traySetToStream( stream, &entry->u.assign.tiles );
break;
case TRADE_TYPE:
XP_ASSERT( entry->u.trade.newTiles.nTiles
== entry->u.trade.oldTiles.nTiles );
traySetToStream( stream, &entry->u.trade.oldTiles );
/* could save three bits per trade by just writing the tiles of the
second guy */
traySetToStream( stream, &entry->u.trade.newTiles );
break;
}
++stack->nEntries;
stack->highWaterMark = stack->nEntries;
stack->top = stream_setPos( stream, oldLoc, POS_WRITE );
} /* pushEntry */
static void
readEntry( StackCtxt* stack, StackEntry* entry )
{
XP_U16 nTiles, i;
XWStreamCtxt* stream = stack->data;
entry->moveType = (StackMoveType)stream_getBits( stream, 2 );
entry->playerNum = (XP_U8)stream_getBits( stream, 2 );
switch( entry->moveType ) {
case MOVE_TYPE:
case PHONY_TYPE:
nTiles = entry->u.move.moveInfo.nTiles =
(XP_U8)stream_getBits( stream, NTILES_NBITS );
XP_ASSERT( nTiles <= MAX_TRAY_TILES );
entry->u.move.moveInfo.commonCoord = (XP_U8)stream_getBits(stream, 5);
entry->u.move.moveInfo.isHorizontal = (XP_U8)stream_getBits(stream, 1);
for ( i = 0; i < nTiles; ++i ) {
entry->u.move.moveInfo.tiles[i].varCoord =
(XP_U8)stream_getBits(stream, 5);
entry->u.move.moveInfo.tiles[i].tile =
(Tile)stream_getBits( stream, 6 );
}
if ( entry->moveType == MOVE_TYPE ) {
traySetFromStream( stream, &entry->u.move.newTiles );
}
break;
case ASSIGN_TYPE:
traySetFromStream( stream, &entry->u.assign.tiles );
break;
case TRADE_TYPE:
traySetFromStream( stream, &entry->u.trade.oldTiles );
traySetFromStream( stream, &entry->u.trade.newTiles );
XP_ASSERT( entry->u.trade.newTiles.nTiles
== entry->u.trade.oldTiles.nTiles );
break;
}
} /* readEntry */
void
stack_addMove( StackCtxt* stack, XP_U16 turn, MoveInfo* moveInfo,
TrayTileSet* newTiles )
{
StackEntry move;
move.playerNum = (XP_U8)turn;
move.moveType = MOVE_TYPE;
XP_MEMCPY( &move.u.move.moveInfo, moveInfo, sizeof(move.u.move.moveInfo));
move.u.move.newTiles = *newTiles;
pushEntry( stack, &move );
} /* stack_addMove */
void
stack_addPhony( StackCtxt* stack, XP_U16 turn, MoveInfo* moveInfo )
{
StackEntry move;
move.playerNum = (XP_U8)turn;
move.moveType = PHONY_TYPE;
XP_MEMCPY( &move.u.phony.moveInfo, moveInfo,
sizeof(move.u.phony.moveInfo));
pushEntry( stack, &move );
} /* stack_addPhony */
void
stack_addTrade( StackCtxt* stack, XP_U16 turn,
TrayTileSet* oldTiles, TrayTileSet* newTiles )
{
StackEntry move;
move.playerNum = (XP_U8)turn;
move.moveType = TRADE_TYPE;
move.u.trade.oldTiles = *oldTiles;
move.u.trade.newTiles = *newTiles;
pushEntry( stack, &move );
} /* stack_addTrade */
void
stack_addAssign( StackCtxt* stack, XP_U16 turn, TrayTileSet* tiles )
{
StackEntry move;
move.playerNum = (XP_U8)turn;
move.moveType = ASSIGN_TYPE;
move.u.assign.tiles = *tiles;
pushEntry( stack, &move );
} /* stack_addAssign */
static XP_Bool
setCacheReadyFor( StackCtxt* stack, XP_U16 n )
{
StackEntry dummy;
XP_U16 i;
stream_setPos( stack->data, START_OF_STREAM, POS_READ );
for ( i = 0; i < n; ++i ) {
readEntry( stack, &dummy );
}
stack->cacheNext = n;
stack->cachedPos = stream_getPos( stack->data, XP_FALSE );
return XP_TRUE;
} /* setCacheReadyFor */
XP_U16
stack_getNEntries( StackCtxt* stack )
{
return stack->nEntries;
} /* stack_getNEntries */
XP_Bool
stack_getNthEntry( StackCtxt* stack, XP_U16 n, StackEntry* entry )
{
XP_Bool found;
if ( n >= stack->nEntries ) {
found = XP_FALSE;
} else if ( stack->cacheNext != n ) {
XP_ASSERT( !!stack->data );
found = setCacheReadyFor( stack, n );
XP_ASSERT( stack->cacheNext == n );
} else {
found = XP_TRUE;
}
if ( found ) {
XWStreamPos oldPos = stream_setPos( stack->data, stack->cachedPos,
POS_READ );
readEntry( stack, entry );
entry->moveNum = (XP_U8)n;
stack->cachedPos = stream_setPos( stack->data, oldPos, POS_READ );
++stack->cacheNext;
}
return found;
} /* stack_getNthEntry */
XP_Bool
stack_popEntry( StackCtxt* stack, StackEntry* entry )
{
XP_U16 n = stack->nEntries - 1;
XP_Bool found = stack_getNthEntry( stack, n, entry );
if ( found ) {
stack->nEntries = n;
setCacheReadyFor( stack, n ); /* set cachedPos by side-effect */
stack->top = stack->cachedPos;
}
return found;
} /* stack_popEntry */
void
stack_redo( StackCtxt* stack )
{
if( (stack->nEntries + 1) <= stack->highWaterMark ) {
++stack->nEntries;
setCacheReadyFor( stack, stack->nEntries );
stack->top = stack->cachedPos;
}
} /* stack_redo */
#ifdef CPLUS
}
#endif