X-Git-Url: http://git.harvie.cz/?a=blobdiff_plain;f=c%2Fpthread_extra%2Fpthread_pause.c;h=c0d43507d12702e4b6174d99d299e8cbbb3700df;hb=7e0f3dba1713edfea98cdfe7909c08f68fa5f7b7;hp=309016c289c3001159a7c94b9201dda47606c5e3;hpb=a8e71e8fffa0159f06b2c469fb2d3dfd8222b306;p=mirrors%2FPrograms.git

diff --git a/c/pthread_extra/pthread_pause.c b/c/pthread_extra/pthread_pause.c
index 309016c..c0d4350 100644
--- a/c/pthread_extra/pthread_pause.c
+++ b/c/pthread_extra/pthread_pause.c
@@ -1,19 +1,118 @@
+#define __PTHREAD_EXTRA_INTERNAL
+
 #include <pthread.h>
 #include <pthread_extra.h>
 #include <signal.h>
-
-void pthread_unpause_handler() {
-	//NOP
-}
+#include <errno.h>
+#include <unistd.h>
+#include <sys/resource.h>
+//#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+//#include <sys/time.h>
 
 void pthread_pause_handler() {
+	//Do nothing when there are more signals pending (to cleanup the queue)
+	sigset_t pending;
+	sigpending(&pending);
+	if(sigismember(&pending, PTHREAD_XSIG_STOP)) return;
+
+	//Keep waiting for signals until we are supposed to be running
 	sigset_t sigset;
 	sigfillset(&sigset);
-	sigdelset(&sigset, PTHREAD_XSIG_CONT);
-	sigsuspend(&sigset);
+	sigdelset(&sigset, PTHREAD_XSIG_STOP);
+	if(!pthread_user_data_internal(pthread_self())->running) {
+		sigsuspend(&sigset);
+	}
 }
 
 void pthread_pause_enable() {
+	//Add thread to internal registry
+	pthread_user_data_internal(pthread_self());
+
+	//Nesting signals too deep is not good for stack
+	//You can get runtime stats using following command:
+	//grep -i sig /proc/$(pgrep binary)/status
+	struct rlimit sigq = {.rlim_cur = 32, .rlim_max=32};
+	setrlimit(RLIMIT_SIGPENDING, &sigq);
+
+	//Setup signal handler
 	signal(PTHREAD_XSIG_STOP, pthread_pause_handler);
-	signal(PTHREAD_XSIG_CONT, pthread_unpause_handler);
+
+	//Unblock signal
+	sigset_t sigset;
+	sigemptyset(&sigset);
+	sigaddset(&sigset, PTHREAD_XSIG_STOP);
+	pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
+}
+
+void pthread_pause_disable() {
+	//Add thread to internal registry
+	pthread_user_data_internal(pthread_self());
+
+	//Block signal
+	sigset_t sigset;
+	sigemptyset(&sigset);
+	sigaddset(&sigset, PTHREAD_XSIG_STOP);
+	pthread_sigmask(SIG_BLOCK, &sigset, NULL);
+}
+
+int pthread_pause_reschedule(pthread_t thread) {
+	//Send signal to initiate pause handler
+	while(pthread_kill(thread, PTHREAD_XSIG_STOP) == EAGAIN) usleep(1000);
+	return 0;
+}
+
+int pthread_pause(pthread_t thread) {
+	//Set thread as paused and notify it via signal (wait when queue full)
+	pthread_user_data_internal(thread)->running = 0;
+	pthread_pause_reschedule(thread);
+	return 0;
+}
+
+int pthread_unpause(pthread_t thread) {
+	//Set thread as running and notify it via signal (wait when queue full)
+	pthread_user_data_internal(thread)->running = 1;
+	pthread_pause_reschedule(thread);
+	return 0;
+}
+
+
+
+// Wrappers ///////////////////////////////////////////////////////////
+
+
+typedef struct pthread_extra_wrapper_t {
+	void *(*start_routine)(void *);
+	void *restrict arg;
+} pthread_extra_wrapper_t;
+
+void *pthread_extra_thread_wrapper(void *arg) {
+	pthread_extra_wrapper_t task = *((pthread_extra_wrapper_t*)arg);
+	free(arg);
+
+	//Register new thread to user data structure
+	pthread_user_data_internal(pthread_self());
+
+	//TODO: user_data should do this automaticaly?
+	pthread_cleanup_push(pthread_user_data_cleanup, (void *)pthread_self());
+
+	//Check if we should be running according to pthread_pause sub-scheduler
+	pthread_pause_reschedule(pthread_self());
+
+	return task.start_routine(task.arg);
+
+	pthread_cleanup_pop(1); //Needed by pthread_cleanup_push() macro
+}
+
+int pthread_extra_create(pthread_t *restrict thread,
+                          const pthread_attr_t *restrict attr,
+                          void *(*start_routine)(void *),
+                          void *restrict arg) {
+
+	pthread_extra_wrapper_t *task = malloc(sizeof(pthread_extra_wrapper_t));
+	assert(task != NULL);
+	task->start_routine=start_routine;
+	task->arg=arg;
+	return pthread_create(thread, attr, pthread_extra_thread_wrapper, task);
 }