From: Tomas Mudrunka <tomas@mudrunka.cz>
Date: Wed, 23 Jun 2021 09:41:32 +0000 (+0200)
Subject: Nastrel pthread_mq
X-Git-Url: https://git.harvie.cz/?a=commitdiff_plain;h=90c3a0d44488720a0ee69d686cad80d83c534797;p=mirrors%2FPrograms.git

Nastrel pthread_mq
---

diff --git a/c/pthread_extra/pthread_msgqueue.c b/c/pthread_extra/pthread_msgqueue.c
new file mode 100644
index 0000000..0d4e07e
--- /dev/null
+++ b/c/pthread_extra/pthread_msgqueue.c
@@ -0,0 +1,93 @@
+/*
+ * CFLAGS=-lpthread make pthread_msgqueue
+ */
+
+#include <pthread.h>
+#include <time.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+typedef struct pthread_mq_t {
+	static pthread_mutex_t lock;
+	static pthread_cond_t cond_readable;
+	static pthread_cond_t cond_writable;
+	void * data;
+	size_t msg_size;
+	size_t msg_count;
+	size_t msg_count_max;
+	size_t head_idx;
+	char * name;
+} pthread_mq_t;
+
+bool pthread_mq_readable(pthread_mq_t *mq) { return (mq->count > 0); }
+bool pthread_mq_writable(pthread_mq_t *mq) { return (mq->count < mq->count_max); }
+
+bool pthread_mq_init(pthread_mq_t *mq, size_t msg_size, size_t msg_count_max) {
+	mq->lock = PTHREAD_MUTEX_INITIALIZER;
+	mq->cond_readable = PTHREAD_COND_INITIALIZER;
+	mq->cond_writable = PTHREAD_COND_INITIALIZER;
+	mq->data = malloc(msg_size*msg_count_max);
+	mq->msg_size = msg_size;
+	mq->msg_count_max = msg_count_max;
+	mq->msg_count = 0;
+	mq->head_idx = 0;
+	mq->name = NULL;
+
+	if(((msg_size*msg_count_max) > 0) && mq->data == NULL) return false;
+	return true;
+}
+
+void pthread_mq_free(pthread_mq_t *mq) {
+	free(mq->data);
+}
+
+
+void pthread_mq_cond(pthread_mq_t *mq) {
+	if(pthread_mq_readable(mq)) pthread_cond_broadcast(&mq->cond_readable);
+	if(pthread_mq_writable(mq)) pthread_cond_broadcast(&mq->cond_writable);
+}
+
+bool pthread_mq_send_generic(pthread_mq_t *mq, void * data, bool to_front, bool block, const struct timespec *restrict abs_timeout) {
+	pthread_mutex_timedlock(&mq->lock, abs_timeout);
+
+	while(!pthread_mq_writable(mq)) {
+		pthread_mutex_unlock(&mq->lock);
+		return false;
+	}
+
+	size_t idx = ( ( mq->count_max + mq->head_idx + (to_front?-1:mq->count) ) % mq->count_max );
+	void *ptr = mq->data + (idx * mq->msg_size);
+	mq->msg_count++;
+	memcpy(ptr, data, mq->msg_size);
+
+	pthread_mq_cond(mq);
+	pthread_mutex_unlock(&mq->lock);
+	return true;
+}
+
+/*
+              mq_timedreceive(3)   mq_timedreceive(2)
+
+              mq_timedsend(3)      mq_timedsend(2)
+
+void vQueueDelete( QueueHandle_t xQueue );
+BaseType_t xQueueReset( QueueHandle_t xQueue );
+
+ BaseType_t xQueueSend(
+                            QueueHandle_t xQueue,
+                            const void * pvItemToQueue,
+                            TickType_t xTicksToWait
+                         );
+ BaseType_t xQueueReceive(
+                               QueueHandle_t xQueue,
+                               void *pvBuffer,
+                               TickType_t xTicksToWait
+                            );
+
+*/
+
+int main() {
+
+}