stk-code_catmod/lib/sheenbidi/Source/ScriptStack.c

84 lines
2.4 KiB
C

/*
* Copyright (C) 2018-2019 Muhammad Tayyab Akram
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <SBConfig.h>
#include "SBAssert.h"
#include "SBBase.h"
#include "ScriptStack.h"
SB_INTERNAL void ScriptStackReset(ScriptStackRef stack)
{
stack->top = -1;
stack->count = 0;
stack->open = 0;
}
SB_INTERNAL void ScriptStackPush(ScriptStackRef stack, SBScript script, SBCodepoint mirror)
{
stack->count = SBNumberLimitIncrement(stack->count, _SBScriptStackCapacity);
stack->open = SBNumberLimitIncrement(stack->open, _SBScriptStackCapacity);
stack->top = SBNumberRingIncrement(stack->top, _SBScriptStackCapacity);
stack->_elements[stack->top].script = script;
stack->_elements[stack->top].mirror = mirror;
}
SB_INTERNAL void ScriptStackPop(ScriptStackRef stack)
{
/* There must be at least one entry in the stack. */
SBAssert(stack->count > 0);
stack->count -= 1;
stack->open = SBNumberLimitDecrement(stack->open, 0);
stack->top = SBNumberRingDecrement(stack->top, _SBScriptStackCapacity);
if (ScriptStackIsEmpty(stack)) {
stack->top = -1;
}
}
SB_INTERNAL void ScriptStackLeavePairs(ScriptStackRef stack)
{
stack->open = 0;
}
SB_INTERNAL void ScriptStackSealPairs(ScriptStackRef stack, SBScript script)
{
SBInteger index = SBNumberRingSubtract(stack->top, (SBInteger)stack->open, _SBScriptStackCapacity);
while (stack->open) {
index = SBNumberRingIncrement(index, _SBScriptStackCapacity);
stack->_elements[index].script = script;
stack->open -= 1;
}
}
SB_INTERNAL SBBoolean ScriptStackIsEmpty(ScriptStackRef stack)
{
return (stack->count == 0);
}
SB_INTERNAL SBScript ScriptStackGetScript(ScriptStackRef stack)
{
return stack->_elements[stack->top].script;
}
SB_INTERNAL SBCodepoint ScriptStackGetMirror(ScriptStackRef stack)
{
return stack->_elements[stack->top].mirror;
}