From: Tomas Mudrunka <tomas@mudrunka.cz>
Date: Fri, 25 Jun 2021 10:56:00 +0000 (+0200)
Subject: pthread_pause pthread_unpause
X-Git-Url: https://git.harvie.cz/?a=commitdiff_plain;h=a8e71e8fffa0159f06b2c469fb2d3dfd8222b306;p=mirrors%2FPrograms.git

pthread_pause pthread_unpause
---

diff --git a/c/pthread_extra/Makefile b/c/pthread_extra/Makefile
index 954e2f6..cf4e674 100644
--- a/c/pthread_extra/Makefile
+++ b/c/pthread_extra/Makefile
@@ -11,13 +11,15 @@ CXXFLAGS+=$(COPT) $(CERR) $(CDEF) -std=c++11 $(CLIB)
 LDFLAGS+=$(COPT) $(LIB)
 
 BIN=test
-OBJ=pthread_multi.o pthread_msgqueue.o test.o
+OBJ=pthread_pause.o pthread_multi.o pthread_msgqueue.o test.o
 
 all: $(BIN)
 $(BIN): $(OBJ)
 	$(CXX) -o $(BIN) $(OBJ) $(LDFLAGS)
 	strip --strip-unneeded $(BIN)
 
+	gcc -lpthread -I . test_pause.c pthread_pause.o -o test_pause
+
 clean:
 	rm -f $(BIN) $(OBJ) $(DEPS)
 
diff --git a/c/pthread_extra/pthread_extra.h b/c/pthread_extra/pthread_extra.h
index e1fe782..bd1baad 100644
--- a/c/pthread_extra/pthread_extra.h
+++ b/c/pthread_extra/pthread_extra.h
@@ -5,10 +5,24 @@
 #include <time.h>
 #include <stdbool.h>
 #include <stdint.h>
+#include <signal.h>
 
 #define PTHREAD_XTIME_NOBLOCK (&(struct timespec){ .tv_sec = 0, .tv_nsec = 0 })
 #define PTHREAD_XTIME_FOREVER NULL
 
+//Pausing
+
+#define PTHREAD_XSIG_STOP (SIGRTMIN+0)
+#define PTHREAD_XSIG_CONT (SIGRTMIN+1)
+#define PTHREAD_XSIGRTMIN (SIGRTMIN+2) //First unused RT signal
+
+#define pthread_pause(t)   (pthread_kill((t), PTHREAD_XSIG_STOP));
+#define pthread_unpause(t) (pthread_kill((t), PTHREAD_XSIG_CONT));
+
+void pthread_unpause_handler();
+void pthread_pause_handler();
+void pthread_pause_enable();
+
 // Message queues
 
 #define PTHREAD_XMQ_FRONT true
diff --git a/c/pthread_extra/pthread_pause.c b/c/pthread_extra/pthread_pause.c
new file mode 100644
index 0000000..309016c
--- /dev/null
+++ b/c/pthread_extra/pthread_pause.c
@@ -0,0 +1,19 @@
+#include <pthread.h>
+#include <pthread_extra.h>
+#include <signal.h>
+
+void pthread_unpause_handler() {
+	//NOP
+}
+
+void pthread_pause_handler() {
+	sigset_t sigset;
+	sigfillset(&sigset);
+	sigdelset(&sigset, PTHREAD_XSIG_CONT);
+	sigsuspend(&sigset);
+}
+
+void pthread_pause_enable() {
+	signal(PTHREAD_XSIG_STOP, pthread_pause_handler);
+	signal(PTHREAD_XSIG_CONT, pthread_unpause_handler);
+}
diff --git a/c/pthread_extra/test.c b/c/pthread_extra/test.c
index 891cd50..f39a979 100644
--- a/c/pthread_extra/test.c
+++ b/c/pthread_extra/test.c
@@ -40,12 +40,21 @@ void *thread_recv() {
 
 	char str[128];
 	while(1) {
-		pthread_mq_receive_generic(&myq, &str, false, PTHREAD_XTIME_FOREVER);
-		printf("RECVD: %.6s\t\t(waiting %d)\n", str, (int)pthread_mq_waiting(&myq));
-		sleep(1);
+		if(pthread_mq_receive_generic(&myq, &str, false, PTHREAD_XTIME_FOREVER))
+			printf("-RECVD: %.6s\t\t(waiting %d)\n", str, (int)pthread_mq_waiting(&myq));
+		if(pthread_mq_receive_generic(&myq, &str, false, PTHREAD_XTIME_NOBLOCK))
+			printf("+RECVD: %.6s\t\t(waiting %d)\n", str, (int)pthread_mq_waiting(&myq));
 	}
 }
 
+void *thread_send() {
+	while(1) {
+		pthread_mq_send_generic(&myq, " X   ", true, PTHREAD_XTIME_NOBLOCK);
+		pthread_mq_send_generic(&myq, " Y   ", false, PTHREAD_XTIME_FOREVER);
+	}
+}
+
+
 int main() {
 	//main_mumu();
 
@@ -55,6 +64,8 @@ int main() {
 
 	pthread_t t;
 	pthread_create(&t, NULL, thread_recv, NULL);
+	pthread_t s;
+	pthread_create(&s, NULL, thread_send, NULL);
 
 	pthread_mq_send_generic(&myq, "AHOJ1", false, NULL);
 	pthread_mq_send_generic(&myq, "AHOJ2", false, NULL);
@@ -64,11 +75,10 @@ int main() {
 	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);
-		sleep(1);
+		pthread_mq_send_generic(&myq, "B    ", false, NULL);
+		pthread_mq_send_generic(&myq, "A    ", true, NULL);
+		pthread_mq_send_generic(&myq, " B   ", false, PTHREAD_XTIME_FOREVER);
+		pthread_mq_send_generic(&myq, " A   ", false, PTHREAD_XTIME_NOBLOCK);
 	}
 
 	pthread_join(t, NULL);
diff --git a/c/pthread_extra/test_pause.c b/c/pthread_extra/test_pause.c
new file mode 100644
index 0000000..47f2db0
--- /dev/null
+++ b/c/pthread_extra/test_pause.c
@@ -0,0 +1,46 @@
+#include <signal.h>
+#include <pthread.h>
+#include <pthread_extra.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <unistd.h>
+
+void *thread_test(void *arg) {
+	//Whole process dies if you kill thread immediately before it is pausable
+	//pthread_pause_enable();
+	while(1) {
+		usleep(1000*300);
+		printf("Running%s!\n", (char *)arg);
+	}
+}
+
+int main() {
+
+	pthread_t a, b;
+	pthread_pause_enable(); //Will get inherited by all threads from now on
+	//That way you can be sure it is pausable immediately
+	pthread_create(&a, NULL, thread_test, " A");
+	pthread_create(&b, NULL, thread_test, " B");
+
+	while(1) {
+		pthread_pause(b);
+		pthread_unpause(a);
+		printf("SWITCH A:\n");
+		sleep(2);
+
+		printf("SWITCH B:\n");
+		pthread_pause(a);
+		pthread_unpause(b);
+		sleep(2);
+
+		printf("SWITCH A+B:\n");
+		pthread_unpause(a);
+		pthread_unpause(b);
+		sleep(1);
+	}
+
+	pthread_join(a, NULL);
+	pthread_join(b, NULL);
+	printf("DIEDED!\n");
+}