From 63658368a85bba1239a9049b6bbd4ea4d87469b2 Mon Sep 17 00:00:00 2001
From: Tomas Mudrunka <tomas@mudrunka.cz>
Date: Wed, 23 Jun 2021 14:54:27 +0200
Subject: [PATCH] Blokovani pres konstantu

---
 c/pthread_extra/pthread_msgqueue.c | 97 ++++++++++++++++++++++++++----
 1 file changed, 85 insertions(+), 12 deletions(-)

diff --git a/c/pthread_extra/pthread_msgqueue.c b/c/pthread_extra/pthread_msgqueue.c
index c4878a5..6e509c7 100644
--- a/c/pthread_extra/pthread_msgqueue.c
+++ b/c/pthread_extra/pthread_msgqueue.c
@@ -9,6 +9,10 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <assert.h>
+#include <unistd.h>
+
+#define PTHREAD_X_NONWAIT (&(struct timespec){ .tv_sec = 0, .tv_nsec = 0 })
+#define PTHREAD_X_FOREVER NULL
 
 typedef struct pthread_mq_t {
 	pthread_mutex_t lock;
@@ -29,6 +33,7 @@ bool pthread_mq_init(pthread_mq_t *mq, size_t msg_size, size_t msg_count_max) {
 	pthread_mutex_init(&mq->lock, NULL);
 	pthread_cond_init(&mq->cond_readable, NULL);
 	pthread_cond_init(&mq->cond_writable, NULL);
+	//pthread_mutexattr_setclock(&mq->lock, CLOCK_MONOTONIC);
 	mq->data = malloc(msg_size*msg_count_max);
 	mq->msg_size = msg_size;
 	mq->msg_count_max = msg_count_max;
@@ -49,6 +54,10 @@ void pthread_mq_cond(pthread_mq_t *mq) {
 	if(pthread_mq_writable(mq)) pthread_cond_broadcast(&mq->cond_writable);
 }
 
+size_t pthread_mq_waiting(pthread_mq_t *mq) {
+	return mq->msg_count;
+}
+
 bool pthread_mq_reset(pthread_mq_t *mq) {
 	if(pthread_mutex_lock(&mq->lock)) return false;
 	mq->msg_count = 0;
@@ -58,7 +67,7 @@ bool pthread_mq_reset(pthread_mq_t *mq) {
 	return true;
 }
 
-bool pthread_mq_send_generic(pthread_mq_t *mq, void * data, bool to_front, bool block, const struct timespec *restrict abs_timeout) {
+bool pthread_mq_send_generic(pthread_mq_t *mq, void * data, bool to_front, const struct timespec *restrict abs_timeout) {
 	int ret;
 
 	//Lock queue
@@ -76,7 +85,6 @@ bool pthread_mq_send_generic(pthread_mq_t *mq, void * data, bool to_front, bool
 			return false;
 		}
 	}
-	printf("Writable\n");
 
 	//Write data to queue
 	size_t idx = ( ( mq->msg_count_max + mq->head_idx + (to_front?-1:mq->msg_count) ) % mq->msg_count_max );
@@ -91,17 +99,82 @@ bool pthread_mq_send_generic(pthread_mq_t *mq, void * data, bool to_front, bool
 	return true;
 }
 
+bool pthread_mq_receive_generic(pthread_mq_t *mq, void * data, bool peek, const struct timespec *restrict abs_timeout) {
+	int ret;
+
+	//Lock queue
+	if(pthread_mutex_timedlock(&mq->lock, abs_timeout)) return false;
+
+	//Wait for queue to be in readable condition
+	while(!pthread_mq_readable(mq)) {
+		if(abs_timeout == NULL) {
+			ret = pthread_cond_wait(&mq->cond_readable, &mq->lock);
+		} else {
+			ret = pthread_cond_timedwait(&mq->cond_readable, &mq->lock, abs_timeout);
+		}
+		if(ret) {
+			pthread_mutex_unlock(&mq->lock);
+			return false;
+		}
+	}
+
+	//Read data from queue
+	void *ptr = mq->data + (mq->head_idx * mq->msg_size);
+	memcpy(data, ptr, mq->msg_size);
+
+	//Delete data from queue if not peeking
+	if(!peek) {
+		mq->msg_count--;
+		mq->head_idx = (mq->head_idx+1) % mq->msg_count_max;
+	}
+
+	//Signal conditions and unlock
+	pthread_mq_cond(mq);
+	pthread_mutex_unlock(&mq->lock);
+	return true;
+}
+
+
+
+
+
+
+
+
+
+
+pthread_mq_t myq;
+
+void *thread_recv(void *args) {
+	char str[128];
+	while(1) {
+		pthread_mq_receive_generic(&myq, &str, false, NULL);
+		printf("RECVD: %.6s\t\t(waiting %d)\n", str, pthread_mq_waiting(&myq));
+		sleep(1);
+	}
+}
+
 int main() {
-	pthread_mq_t myq;
+	char tmp[128];
+
 	pthread_mq_init(&myq, 6, 5);
-	pthread_mq_send_generic(&myq, "AHOJ1", false, true, NULL);
-	pthread_mq_send_generic(&myq, "AHOJ2", false, true, NULL);
-	pthread_mq_send_generic(&myq, "AHOJ3", true, true, NULL);
-	pthread_mq_send_generic(&myq, "AHOJ4", true, true, NULL);
-	pthread_mq_send_generic(&myq, "AHOJ5", false, true, NULL);
-	//pthread_mq_send_generic(&myq, "AHOJ6", false, true, NULL);
-
-	for(int i = 0; i<5; i++) {
-		printf("%.6s\n", (char *)(myq.data+i*6));
+
+	pthread_t t;
+	pthread_create(&t, NULL, thread_recv, NULL);
+
+	pthread_mq_send_generic(&myq, "AHOJ1", false, NULL);
+	pthread_mq_send_generic(&myq, "AHOJ2", false, NULL);
+	pthread_mq_send_generic(&myq, "AHOJ3", true, NULL);
+	pthread_mq_send_generic(&myq, "AHOJ4", true, NULL);
+	pthread_mq_send_generic(&myq, "AHOJ5", false, NULL);
+	pthread_mq_send_generic(&myq, "AHOJ6", true, NULL);
+
+	while(1) {
+		pthread_mq_send_generic(&myq, "B", false, NULL);
+		pthread_mq_send_generic(&myq, "A", true, NULL);
+		pthread_mq_send_generic(&myq, " A", false, NULL);
+		pthread_mq_send_generic(&myq, " B", false, NULL);
 	}
+
+	pthread_join(t, NULL);
 }
-- 
2.30.2