diff options
Diffstat (limited to 'queue.c')
-rw-r--r-- | queue.c | 60 |
1 files changed, 60 insertions, 0 deletions
@@ -0,0 +1,60 @@ +/* + * Copyright (C) 2024 Mikhail Burakov. This file is part of streamer. + * + * streamer 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. + * + * streamer 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 streamer. If not, see <https://www.gnu.org/licenses/>. + */ + +#include "queue.h" + +#include <assert.h> +#include <stdlib.h> +#include <string.h> + +void QueueCreate(struct Queue* queue) { + memset(queue, 0, sizeof(struct Queue)); +} + +bool QueuePush(struct Queue* queue, void* item) { + if (queue->size == queue->alloc) { + size_t alloc = queue->alloc + 1; + void** buffer = malloc(alloc * sizeof(void*)); + if (!buffer) return false; + + size_t head_size = queue->read; + size_t tail_size = queue->size - queue->read; + memcpy(buffer, queue->buffer + queue->read, tail_size * sizeof(void*)); + memcpy(buffer + tail_size, queue->buffer, head_size * sizeof(void*)); + free(queue->buffer); + + queue->buffer = buffer; + queue->alloc = alloc; + queue->read = 0; + queue->write = queue->size; + } + + queue->buffer[queue->write] = item; + queue->write = (queue->write + 1) % queue->alloc; + queue->size++; + return true; +} + +bool QueuePop(struct Queue* queue, void** pitem) { + if (!queue->size) return false; + *pitem = queue->buffer[queue->read]; + queue->read = (queue->read + 1) % queue->alloc; + queue->size--; + return true; +} + +void QueueDestroy(struct Queue* queue) { free(queue->buffer); } |