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Fixed unsafe race condition queue functions, queue.c #279

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merged 1 commit into from
Jul 6, 2024
Merged

Fixed unsafe race condition queue functions, queue.c #279

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142 changes: 84 additions & 58 deletions queue.c
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Original file line number Diff line number Diff line change
Expand Up @@ -7,106 +7,123 @@
#include "queue.h"


uint8_t
__CQueue_full_no_lock(CQueue *queue)
{ return (queue->front == queue->rear + 1) | ((!queue->front) & (queue->rear == (queue->datalen / (queue->datasize + !queue->datasize) - 1)));
}

uint8_t
CQueueIsFull(CQueue *queue)
{
pthread_mutex_lock(&queue->mutex);
if(queue)
{ return (queue->front == queue->rear + 1) | ((!queue->front) & (queue->rear == (queue->datalen / (queue->datasize + !queue->datasize) - 1)));
if(!queue)
{ return 0;
}
pthread_mutex_unlock(&queue->mutex);
return 0;
pthread_spin_lock(&queue->spin);
uint8_t ret = __CQueue_full_no_lock(queue);
pthread_spin_unlock(&queue->spin);
return ret;
}

uint8_t
CQueueIsEmpty(CQueue *queue)
{
pthread_mutex_lock(&queue->mutex);
if(queue)
{ return (queue->front == -1);
if(!queue)
{ return 0;
}
pthread_mutex_unlock(&queue->mutex);
return 0;
pthread_spin_lock(&queue->spin);
uint8_t status = queue->front == -1;
pthread_spin_unlock(&queue->spin);
return status;
}

uint8_t
CQueuePop(CQueue *queue)
{
pthread_mutex_lock(&queue->mutex);
if(queue)
{
if(queue->front == -1)
{ return 0;
}
if(queue->front == queue->rear)
{ queue->front = queue->rear = -1;
}
else
{ queue->front = (queue->front + 1) % queue->datalen;
}
return 1;
if(!queue)
{ return 0;
}
pthread_mutex_unlock(&queue->mutex);
return 0;
pthread_spin_lock(&queue->spin);
if(queue->front == -1)
{
pthread_spin_unlock(&queue->spin);
return 0;
}
if(queue->front == queue->rear)
{ queue->front = queue->rear = -1;
}
else
{ queue->front = (queue->front + 1) % queue->datalen;
}
pthread_spin_unlock(&queue->spin);
return 1;
}

uint8_t
CQueueAdd(CQueue *queue, void *data)
{
pthread_mutex_lock(&queue->mutex);
if(queue)
if(!queue)
{ return 0;
}
size_t size;
pthread_spin_lock(&queue->spin);
if(__CQueue_full_no_lock(queue))
{
if(CQueueIsFull(queue))
{ return 0;
}

if(queue->front == -1)
{ queue->front = 0;
}

queue->rear = (queue->rear + 1) % queue->datalen;
memcpy(queue->data[queue->rear], data, queue->datasize);
return 1;
pthread_spin_unlock(&queue->spin);
return 0;
}
pthread_spin_unlock(&queue->spin);
pthread_mutex_lock(&queue->mutex);

if(queue->front == -1)
{ queue->front = 0;
}

queue->rear = (queue->rear + 1) % queue->datalen;
size = queue->datasize;
memcpy((uint8_t *)queue->data + size * queue->rear, data, size);

pthread_cond_signal(&queue->cond);
pthread_mutex_unlock(&queue->mutex);
return 0;
return 1;
}

void *
CQueueGetFirst(CQueue *queue)
{
pthread_mutex_lock(&queue->mutex);
if(queue)
{
if(queue->front == -1)
{ return NULL;
}
return queue->data[queue->front];
void *ret = NULL;
if(!queue)
{ return ret;
}
pthread_mutex_unlock(&queue->mutex);
return NULL;

pthread_spin_lock(&queue->spin);
if(queue->front != -1)
{ ret = (uint8_t *)queue->data + queue->rear * queue->datasize;
}
pthread_spin_unlock(&queue->spin);
return ret;
}

void *
CQueueGetLast(CQueue *queue)
{
pthread_mutex_lock(&queue->mutex);
if(queue)
{
if(queue->rear == -1)
{ return NULL;
}
return queue->data[queue->rear];
void *ret = NULL;
if(!queue)
{ return ret;
}
pthread_mutex_unlock(&queue->mutex);
return NULL;
pthread_spin_lock(&queue->spin);
if(queue->rear != -1)
{ ret = (uint8_t *)queue->data + queue->rear * queue->datasize;
}
pthread_spin_unlock(&queue->spin);
return ret;
}

uint8_t
CQueueCreate(void **data, uint32_t datalen, size_t sizeof_one_item, CQueue *_Q_RETURN)
CQueueCreate(void *data, uint32_t datalen, size_t sizeof_one_item, CQueue *_Q_RETURN)
{
pthread_mutex_t mutex;
pthread_cond_t cond;
pthread_spinlock_t spinlock;
if(pthread_mutex_init(&mutex, NULL))
{ return 1;
}
Expand All @@ -115,13 +132,21 @@ CQueueCreate(void **data, uint32_t datalen, size_t sizeof_one_item, CQueue *_Q_R
pthread_mutex_destroy(&mutex);
return 1;
}
if(pthread_spin_init(&spinlock, 0))
{
pthread_mutex_destroy(&mutex);
pthread_cond_destroy(&cond);
return 1;
}
CQueue queue;
queue.data = data;
queue.datasize = sizeof_one_item;
queue.datalen = datalen;
queue.rear = -1;
queue.front = -1;
queue.mutex = mutex;
queue.cond = cond;
queue.spin = spinlock;
*_Q_RETURN = queue;
return 0;
}
Expand All @@ -131,6 +156,7 @@ CQueueDestroy(CQueue *queue)
{
pthread_mutex_destroy(&queue->mutex);
pthread_cond_destroy(&queue->cond);
pthread_spin_destroy(&queue->spin);
}


6 changes: 4 additions & 2 deletions queue.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,11 +12,13 @@ struct CQueue
{
int64_t front;
int64_t rear;
void **data;
void *data;
uint32_t datalen;
size_t datasize;
pthread_mutex_t mutex;
pthread_cond_t cond;
pthread_spinlock_t spin;
uint8_t pad0[4];
};

/*
Expand Down Expand Up @@ -54,7 +56,7 @@ void *CQueueGetLast(CQueue *queue);
* RETURN: 0 on Success.
* RETURN: 1 on Failure.
*/
uint8_t CQueueCreate(void **data, uint32_t datalen, size_t size_of_one_item, CQueue *_Q_RETURN);
uint8_t CQueueCreate(void *data, uint32_t datalen, size_t size_of_one_item, CQueue *_Q_RETURN);
/* Frees any data from queue.
*/
void CQueueDestroy(CQueue *queue);
Expand Down