126 lines
4.1 KiB
C++
126 lines
4.1 KiB
C++
/* ScummVM - Graphic Adventure Engine
|
|
*
|
|
* ScummVM is the legal property of its developers, whose names
|
|
* are too numerous to list here. Please refer to the COPYRIGHT
|
|
* file distributed with this source distribution.
|
|
*
|
|
* 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/>.
|
|
*
|
|
*/
|
|
|
|
#include "glk/alan3/state_stack.h"
|
|
#include "glk/alan3/syserr.h"
|
|
#include "glk/alan3/memory.h"
|
|
#include "glk/alan3/state.h"
|
|
|
|
namespace Glk {
|
|
namespace Alan3 {
|
|
|
|
/* CONSTANTS: */
|
|
#define EXTENT 10
|
|
|
|
|
|
/* PRIVATE TYPES: */
|
|
struct StateStackStructure {
|
|
void **states;
|
|
char **commands;
|
|
int stackSize;
|
|
int stackPointer; /* Points above used stack, 0 initially */
|
|
int elementSize; /* Size of elements in the stack */
|
|
};
|
|
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
static void *reallocate(void *from, int newSize) {
|
|
void *newArea = realloc(from, newSize * sizeof(void *));
|
|
if (newArea == nullptr)
|
|
syserr("Out of memory in 'reallocateStack()'");
|
|
return newArea;
|
|
}
|
|
|
|
/*======================================================================*/
|
|
StateStackP createStateStack(int elementSize) {
|
|
StateStackP stack = NEW(StateStackStructure);
|
|
stack->stackSize = 0;
|
|
stack->stackPointer = 0;
|
|
stack->elementSize = elementSize;
|
|
return stack;
|
|
}
|
|
|
|
|
|
/*======================================================================*/
|
|
void deleteStateStack(StateStackP stateStack) {
|
|
if (stateStack != nullptr) {
|
|
while (stateStack->stackPointer > 0) {
|
|
stateStack->stackPointer--;
|
|
deallocateGameState((GameState *)stateStack->states[stateStack->stackPointer]);
|
|
deallocate(stateStack->states[stateStack->stackPointer]);
|
|
deallocate(stateStack->commands[stateStack->stackPointer]);
|
|
}
|
|
if (stateStack->stackSize > 0) {
|
|
deallocate(stateStack->states);
|
|
deallocate(stateStack->commands);
|
|
}
|
|
deallocate(stateStack);
|
|
}
|
|
}
|
|
|
|
|
|
/*======================================================================*/
|
|
bool stateStackIsEmpty(StateStackP stateStack) {
|
|
return stateStack->stackPointer == 0;
|
|
}
|
|
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
static void ensureSpaceForGameState(StateStackP stack) {
|
|
if (stack->stackPointer == stack->stackSize) {
|
|
stack->states = (void **)reallocate(stack->states, stack->stackSize + EXTENT);
|
|
stack->commands = (char **)reallocate(stack->commands, stack->stackSize + EXTENT);
|
|
stack->stackSize += EXTENT;
|
|
}
|
|
}
|
|
|
|
|
|
/*======================================================================*/
|
|
void pushGameState(StateStackP stateStack, void *gameState) {
|
|
void *element = allocate(stateStack->elementSize);
|
|
memcpy(element, gameState, stateStack->elementSize);
|
|
ensureSpaceForGameState(stateStack);
|
|
stateStack->commands[stateStack->stackPointer] = nullptr;
|
|
stateStack->states[stateStack->stackPointer++] = element;
|
|
}
|
|
|
|
|
|
/*======================================================================*/
|
|
void attachPlayerCommandsToLastState(StateStackP stateStack, char *playerCommands) {
|
|
stateStack->commands[stateStack->stackPointer - 1] = scumm_strdup(playerCommands);
|
|
}
|
|
|
|
|
|
/*======================================================================*/
|
|
void popGameState(StateStackP stateStack, void *gameState, char **playerCommand) {
|
|
if (stateStack->stackPointer == 0)
|
|
syserr("Popping GameState from empty stack");
|
|
else {
|
|
stateStack->stackPointer--;
|
|
memcpy(gameState, stateStack->states[stateStack->stackPointer], stateStack->elementSize);
|
|
deallocate(stateStack->states[stateStack->stackPointer]);
|
|
*playerCommand = stateStack->commands[stateStack->stackPointer];
|
|
}
|
|
}
|
|
|
|
} // End of namespace Alan3
|
|
} // End of namespace Glk
|