JacksEscape/util/queue.c

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C
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2024-02-29 09:48:29 +08:00
#include "queue.h"
#include <stdio.h>
void queue_InitBuffered(queue *q, void *buffer, uintptr_t size) {
q->data = q->begin = q->end = buffer;
q->size = size;
q->count = 0;
}
void queue_PushByte(queue *q, const uint8_t b) {
if (q->count == q->size) { // no more space
fprintf(stderr, "queue_PushByte: full[%llu bytes], discarding byte 0x%x\n", q->size, b);
return;
}
q->count++;
*((uint8_t *)(q->end++)) = b;
if (q->end == q->data + q->size)
q->end = q->data; // out of the buffer: wrap around
}
uint8_t queue_PopByte(queue *q) {
if (q->count == 0) {
fprintf(stderr, "queue_PopByte: poping an empty queue\n");
return 0;
}
q->count--;
uint8_t data = *((uint8_t *)(q->begin++));
if (q->begin == q->data + q->size)
q->begin = q->data; // wrap around
return data;
}
void queue_Push(queue *q, const void *buffer, uintptr_t size) {
// TODO Optimize queue_Push and queue_Pop
if (queue_Space(q) < size)
return;
for (const uint8_t *i = buffer; i < (const uint8_t *)buffer + size; i++)
queue_PushByte(q, *i);
}
uintptr_t queue_Pop(queue *q, void *buffer, uintptr_t size) {
if (queue_Size(q) < size)
return 0;
for (uint8_t *i = buffer; i < (uint8_t *)buffer + size; i++)
*i = queue_PopByte(q);
return size;
}
uint8_t queue_FrontByte(queue *q) {
if (q->count == 0) {
fprintf(stderr, "queue_TopByte: accessing an empty queue\n");
return 0;
}
return *((uint8_t *)q->begin);
}
bool queue_Empty(queue *q) {
return q->count == 0;
}
uintptr_t queue_Size(queue *q) {
return q->count;
}
uintptr_t queue_Space(queue *q) {
return q->size - q->count;
}