/*
 * FreeRTOS V202111.00
 * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * https://www.FreeRTOS.org
 * https://github.com/FreeRTOS
 *
 */

/*
 * FreeRTOS memory safety proofs with CBMC.
 */

#include "cbmc.h"

/*
 * We allocate an unconstrained TCB or return NULL if it fails
 */
TaskHandle_t xUnconstrainedTCB( void )
{
    TCB_t * pxTCB = pvPortMalloc( sizeof( TCB_t ) );

    if( pxTCB == NULL )
    {
        return NULL;
    }

    return pxTCB;
}

StaticTask_t * pxIdleTaskTCB;
StaticTask_t * pxTimerTaskTCB;
StackType_t * pxIdleTaskStack;
StackType_t * pxTimerTaskStack;

/*
 * `pxCurrentTCB` allocation is allowed to fail. The global variables above
 * this comment are used in the stubbed functions `vApplicationGetIdleTaskMemory`
 * and `vApplicationGetTimerTaskMemory` (at the end of this file) and buffer allocation
 * must be successful for the proof to have no errors
 */
BaseType_t xPrepareTasks( void )
{
    __CPROVER_assert_zero_allocation();

    prvInitialiseTaskLists();

    pxCurrentTCB = xUnconstrainedTCB();

    pxIdleTaskTCB = pvPortMalloc( sizeof( StaticTask_t ) );

    if( pxIdleTaskTCB == NULL )
    {
        return pdFAIL;
    }

    pxIdleTaskStack = pvPortMalloc( sizeof( StackType_t ) * configMINIMAL_STACK_SIZE );

    if( pxIdleTaskStack == NULL )
    {
        return pdFAIL;
    }

    pxTimerTaskTCB = pvPortMalloc( sizeof( StaticTask_t ) );

    if( pxTimerTaskTCB == NULL )
    {
        return pdFAIL;
    }

    pxTimerTaskStack = pvPortMalloc( sizeof( StackType_t ) * configTIMER_TASK_STACK_DEPTH );

    if( pxTimerTaskStack == NULL )
    {
        return pdFAIL;
    }

    return pdPASS;
}

/*
 * The buffers used here have been successfully allocated before (global variables)
 */
void vApplicationGetIdleTaskMemory( StaticTask_t ** ppxIdleTaskTCBBuffer,
                                    StackType_t ** ppxIdleTaskStackBuffer,
                                    uint32_t * pulIdleTaskStackSize )
{
    *ppxIdleTaskTCBBuffer = pxIdleTaskTCB;
    *ppxIdleTaskStackBuffer = pxIdleTaskStack;
    *pulIdleTaskStackSize = configMINIMAL_STACK_SIZE;
}

/*
 * The buffers used here have been successfully allocated before (global variables)
 */
void vApplicationGetTimerTaskMemory( StaticTask_t ** ppxTimerTaskTCBBuffer,
                                     StackType_t ** ppxTimerTaskStackBuffer,
                                     uint32_t * pulTimerTaskStackSize )
{
    *ppxTimerTaskTCBBuffer = pxTimerTaskTCB;
    *ppxTimerTaskStackBuffer = pxTimerTaskStack;
    *pulTimerTaskStackSize = configTIMER_TASK_STACK_DEPTH;
}