3 /* A (synchronized) message queue. */
4 /* Popping an empty queue is blocking, as well as pushing a full one */
6 /* Copyright (c) 2007 Martin Quinson. All rights reserved. */
8 /* This program is free software; you can redistribute it and/or modify it
9 * under the terms of the license (GNU LGPL) which comes with this package. */
12 #include "xbt/sysdep.h"
15 #include "xbt/dynar.h"
17 #include "xbt/synchro.h"
18 #include "xbt/queue.h" /* this module */
20 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_queue,xbt,"Message exchanging queue");
22 typedef struct s_xbt_queue_ {
26 xbt_cond_t not_full, not_empty;
29 /** @brief Create a new message exchange queue.
31 * @param capacity the capacity of the queue. If non-nul, any attempt to push an item which would let the size of the queue over this number will be blocking until someone else pop some data
32 * @param elm_size size of each element stored in it (see #xbt_dynar_new)
34 xbt_queue_t xbt_queue_new(int capacity,unsigned long elm_size) {
35 xbt_queue_t res = xbt_new0(s_xbt_queue_t,1);
36 xbt_assert0(capacity>=0,"Capacity cannot be negative");
38 res->capacity = capacity;
39 res->data = xbt_dynar_new(elm_size,NULL);
40 res->mutex = xbt_mutex_init();
41 res->not_full = xbt_cond_init();
42 res->not_empty = xbt_cond_init();
45 /** @brief Destroy a message exchange queue.
47 * Any remaining content is leaked.
49 void xbt_queue_free(xbt_queue_t *queue) {
51 xbt_dynar_free(&( (*queue)->data ));
52 xbt_mutex_destroy( (*queue)->mutex );
53 xbt_cond_destroy( (*queue)->not_full );
54 xbt_cond_destroy( (*queue)->not_empty );
59 /** @brief Get the queue size */
60 unsigned long xbt_queue_length(xbt_queue_t queue) {
62 xbt_mutex_lock(queue->mutex);
63 res=xbt_dynar_length(queue->data);
64 xbt_mutex_unlock(queue->mutex);
68 /** @brief Push something to the message exchange queue.
70 * This is blocking if the declared capacity is non-nul, and if this amount is reached.
72 * @seealso #xbt_dynar_push
74 void xbt_queue_push(xbt_queue_t queue, const void *src) {
75 xbt_mutex_lock(queue->mutex);
76 while (queue->capacity != 0 && queue->capacity == xbt_dynar_length(queue->data)) {
77 DEBUG2("Capacity of %p exceded (=%d). Waiting",queue,queue->capacity);
78 xbt_cond_wait(queue->not_full,queue->mutex);
80 xbt_dynar_push(queue->data,src);
81 xbt_cond_signal(queue->not_empty);
85 /** @brief Pop something from the message exchange queue.
87 * This is blocking if the queue is empty.
89 * @seealso #xbt_dynar_pop
92 void xbt_queue_pop(xbt_queue_t queue, void* const dst) {
93 xbt_mutex_lock(queue->mutex);
94 while (xbt_dynar_length(queue->data) == 0) {
95 DEBUG1("Queue %p empty. Waiting",queue);
96 xbt_cond_wait(queue->not_empty,queue->mutex);
98 xbt_dynar_pop(queue->data,dst);
99 xbt_cond_signal(queue->not_full);
102 /** @brief Unshift something to the message exchange queue.
104 * This is blocking if the declared capacity is non-nul, and if this amount is reached.
106 * @seealso #xbt_dynar_unshift
108 void xbt_queue_unshift(xbt_queue_t queue, const void *src) {
109 xbt_mutex_lock(queue->mutex);
110 while (queue->capacity != 0 && queue->capacity == xbt_dynar_length(queue->data)) {
111 DEBUG2("Capacity of %p exceded (=%d). Waiting",queue,queue->capacity);
112 xbt_cond_wait(queue->not_full,queue->mutex);
114 xbt_dynar_unshift(queue->data,src);
115 xbt_cond_signal(queue->not_empty);
119 /** @brief Shift something from the message exchange queue.
121 * This is blocking if the queue is empty.
123 * @seealso #xbt_dynar_shift
126 void xbt_queue_shift(xbt_queue_t queue, void* const dst) {
127 xbt_mutex_lock(queue->mutex);
128 while (xbt_dynar_length(queue->data) == 0) {
129 DEBUG1("Queue %p empty. Waiting",queue);
130 xbt_cond_wait(queue->not_empty,queue->mutex);
132 xbt_dynar_shift(queue->data,dst);
133 xbt_cond_signal(queue->not_full);
139 /** @brief Push something to the message exchange queue, with a timeout.
141 * @seealso #xbt_queue_push
143 void xbt_queue_push_timed(xbt_queue_t queue, const void *src,double delay) {
144 xbt_mutex_lock(queue->mutex);
145 while (queue->capacity != 0 && queue->capacity == xbt_dynar_length(queue->data)) {
146 DEBUG2("Capacity of %p exceded (=%d). Waiting",queue,queue->capacity);
147 xbt_cond_timedwait(queue->not_full,queue->mutex, delay);
149 xbt_dynar_push(queue->data,src);
150 xbt_cond_signal(queue->not_empty);
154 /** @brief Pop something from the message exchange queue, with a timeout.
156 * @seealso #xbt_queue_pop
159 void xbt_queue_pop_timed(xbt_queue_t queue, void* const dst,double delay) {
160 xbt_mutex_lock(queue->mutex);
161 while (xbt_dynar_length(queue->data) == 0) {
162 DEBUG1("Queue %p empty. Waiting",queue);
163 xbt_cond_timedwait(queue->not_empty,queue->mutex,delay);
165 xbt_dynar_pop(queue->data,dst);
166 xbt_cond_signal(queue->not_full);
169 /** @brief Unshift something to the message exchange queue, with a timeout.
171 * @seealso #xbt_queue_unshift
173 void xbt_queue_unshift_timed(xbt_queue_t queue, const void *src,double delay) {
174 xbt_mutex_lock(queue->mutex);
175 while (queue->capacity != 0 && queue->capacity == xbt_dynar_length(queue->data)) {
176 DEBUG2("Capacity of %p exceded (=%d). Waiting",queue,queue->capacity);
177 xbt_cond_timedwait(queue->not_full,queue->mutex,delay);
179 xbt_dynar_unshift(queue->data,src);
180 xbt_cond_signal(queue->not_empty);
184 /** @brief Shift something from the message exchange queue, with a timeout.
186 * @seealso #xbt_queue_shift
189 void xbt_queue_shift_timed(xbt_queue_t queue, void* const dst,double delay) {
190 xbt_mutex_lock(queue->mutex);
191 while (xbt_dynar_length(queue->data) == 0) {
192 DEBUG1("Queue %p empty. Waiting",queue);
193 xbt_cond_timedwait(queue->not_empty,queue->mutex,delay);
195 xbt_dynar_shift(queue->data,dst);
196 xbt_cond_signal(queue->not_full);