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Diffstat (limited to 'libmiav/queue.h')
-rw-r--r-- | libmiav/queue.h | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/libmiav/queue.h b/libmiav/queue.h new file mode 100644 index 0000000..3cb6fbc --- /dev/null +++ b/libmiav/queue.h @@ -0,0 +1,248 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * queue.h + * + * Tue Nov 9 10:57:20 CET 2004 + * Copyright 2004 Bent Bisballe + * deva@aasimon.org + ****************************************************************************/ + +/* + * Originally from: + * RTVideoRec Realtime video recoder and encoder for Linux + * + * Copyright (C) 2004 B. Stultiens + */ + +/* + * This file is part of MIaV. + * + * MIaV 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 2 of the License, or + * (at your option) any later version. + * + * MIaV 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 MIaV; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ +#include "config.h" +#ifndef __RTVIDEOREC_QUEUE_H +#define __RTVIDEOREC_QUEUE_H + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> +//#include <avformat.h> +//#include <avcodec.h> + +#include "thread.h" +#include "util.h" + +typedef struct __buf_t { + struct __buf_t *next; + struct __buf_t *prev; + void *data; +} buf_t; + + +template<typename T> +class Queue { +public: + Queue(int glimit = 0); + ~Queue(); + + void push(T *t); + T *pop(); + T *peek(); + + void lock(); + void unlock(); + + int length(); + +private: + volatile bool locked; + int limit; + buf_t *head; + buf_t *tail; + int count; + pthread_mutex_t mutex; + T *_pop(); +}; + +/** + * Initialize queue + */ +template<typename T> +Queue<T>::Queue(int glimit) +{ + locked = false; + pthread_mutex_init (&mutex, NULL); + limit = glimit; + count = 0; + head = NULL; + tail = NULL; +} + +/** + * Clean up queue. + */ +template<typename T> +Queue<T>::~Queue() +{ + if(count != 0) { + fprintf(stderr, "Queue not empty (%d)\n", count); + while(T *t = _pop()) delete t; + } + pthread_mutex_destroy(&mutex); +} + +/** + * Push element on queue. + */ +template<typename T> +void Queue<T>::push(T *t) +{ + if(locked) { + delete t; + return; + } + + pthread_mutex_lock(&mutex); + + buf_t *b = (buf_t*)xmalloc(sizeof(*b)); + b->data = (void*)t; + + assert(b != NULL); + + if(limit && count > 0) { + T* tmp = (T*)_pop(); + delete tmp; + } + + if(!head) { + head = tail = b; + b->next = b->prev = NULL; + count = 1; + pthread_mutex_unlock(&mutex); + return; + } + + b->next = tail; + b->prev = NULL; + if(tail) + tail->prev = b; + tail = b; + count++; + + pthread_mutex_unlock(&mutex); +} + +/** + * Pop element from queue. + * If queue is empty, NULL is returned. + */ +template<typename T> +T *Queue<T>::pop() +{ + pthread_mutex_lock(&mutex); + T *d = _pop(); + pthread_mutex_unlock(&mutex); + return d; +} + +/** + * Pop helper method + * If queue is empty, NULL is returned. + */ +template<typename T> +T *Queue<T>::_pop() +{ + T *d; + buf_t *b; + + assert(count >= 0); + + if(count == 0) { + return NULL; + } + + b = head; + if(b->prev) + b->prev->next = NULL; + head = b->prev; + if(b == tail) + tail = NULL; + count--; + + d = (T*)b->data; + free(b); + + return d; +} + +/** + * Peek foremost element in queue + * If queue is empty, NULL is returned. + */ +template<typename T> +T *Queue<T>::peek() +{ + // pthread_mutex_lock(&mutex); + T *d; + + // assert(count >= 0); + + if(count == 0) { + return NULL; + } + + d = (T*)head->data; + // pthread_mutex_unlock(&mutex); + return d; +} + +/** + * Print current length of queue + */ +template<typename T> +int Queue<T>::length() +{ + int length; + pthread_mutex_lock(&mutex); + length = count; + pthread_mutex_unlock(&mutex); + return length; +} + +/** + * Lock the queue (all elements pushed from this point will be deleted.) + */ +template<typename T> +void Queue<T>::lock() +{ + fprintf(stderr, "Lock this motherfucker..."); fflush(stderr); + locked = true; + fprintf(stderr, "done\n"); fflush(stderr); +} + +/** + * Unlock the queue. + */ +template<typename T> +void Queue<T>::unlock() +{ + fprintf(stderr, "Unlock this motherfucker..."); fflush(stderr); + locked = false; + fprintf(stderr, "done\n"); fflush(stderr); +} + +#endif + |