X-Git-Url: http://plrg.eecs.uci.edu/git/?p=c11tester.git;a=blobdiff_plain;f=model.cc;h=f1df6ae8bfbbdacd806f56976de6b1c2f2bc8099;hp=66af988821af8ef491191a0cfb80151092ef38fd;hb=e45f16f22c8e36652a8f11f6f085ac43da24e1a8;hpb=86b818595e02c86250a17ed88f2d6af15a3141f3

diff --git a/model.cc b/model.cc
index 66af9888..f1df6ae8 100644
--- a/model.cc
+++ b/model.cc
@@ -18,37 +18,74 @@
 #include "history.h"
 #include "bugmessage.h"
 #include "params.h"
+#include "plugins.h"
 
 ModelChecker *model = NULL;
 
-/** Wrapper to run the user's main function, with appropriate arguments */
-void user_main_wrapper(void *)
+void placeholder(void *) {
+	ASSERT(0);
+}
+
+#include <signal.h>
+
+#define SIGSTACKSIZE 65536
+static void mprot_handle_pf(int sig, siginfo_t *si, void *unused)
 {
-	user_main(model->params.argc, model->params.argv);
+	model_print("Segmentation fault at %p\n", si->si_addr);
+	model_print("For debugging, place breakpoint at: %s:%d\n",
+							__FILE__, __LINE__);
+	print_trace();	// Trace printing may cause dynamic memory allocation
+	while(1)
+		;
+}
+
+void install_handler() {
+	stack_t ss;
+	ss.ss_sp = model_malloc(SIGSTACKSIZE);
+	ss.ss_size = SIGSTACKSIZE;
+	ss.ss_flags = 0;
+	sigaltstack(&ss, NULL);
+	struct sigaction sa;
+	sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART | SA_ONSTACK;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_sigaction = mprot_handle_pf;
+
+	if (sigaction(SIGSEGV, &sa, NULL) == -1) {
+		perror("sigaction(SIGSEGV)");
+		exit(EXIT_FAILURE);
+	}
+
 }
 
 /** @brief Constructor */
 ModelChecker::ModelChecker() :
 	/* Initialize default scheduler */
 	params(),
-	restart_flag(false),
 	scheduler(new Scheduler()),
-	execution(new ModelExecution(this, scheduler)),
 	history(new ModelHistory()),
+	execution(new ModelExecution(this, scheduler)),
 	execution_number(1),
 	trace_analyses(),
 	inspect_plugin(NULL)
 {
+	model_print("C11Tester\n"
+							"Copyright (c) 2013 and 2019 Regents of the University of California. All rights reserved.\n"
+							"Distributed under the GPLv2\n"
+							"Written by Weiyu Luo, Brian Norris, and Brian Demsky\n\n");
 	memset(&stats,0,sizeof(struct execution_stats));
-	init_thread = new Thread(execution->get_next_id(), (thrd_t *) model_malloc(sizeof(thrd_t)), &user_main_wrapper, NULL, NULL);	// L: user_main_wrapper passes the user program
+	init_thread = new Thread(execution->get_next_id(), (thrd_t *) model_malloc(sizeof(thrd_t)), &placeholder, NULL, NULL);
 #ifdef TLS
 	init_thread->setTLS((char *)get_tls_addr());
 #endif
 	execution->add_thread(init_thread);
 	scheduler->set_current_thread(init_thread);
+	register_plugins();
 	execution->setParams(&params);
 	param_defaults(&params);
+	parse_options(&params);
 	initRaceDetector();
+	/* Configure output redirection for the model-checker */
+	install_handler();
 }
 
 /** @brief Destructor */
@@ -77,7 +114,7 @@ void ModelChecker::reset_to_initial_state()
 	for (unsigned int i = 0;i < get_num_threads();i++)
 		delete get_thread(int_to_id(i))->get_pending();
 
-	snapshot_backtrack_before(0);
+	snapshot_roll_back(snapshot);
 }
 
 /** @return the number of user threads created during this execution */
@@ -130,7 +167,7 @@ Thread * ModelChecker::get_next_thread()
  * @param msg Descriptive message for the bug (do not include newline char)
  * @return True if bug is immediately-feasible
  */
-bool ModelChecker::assert_bug(const char *msg, ...)
+void ModelChecker::assert_bug(const char *msg, ...)
 {
 	char str[800];
 
@@ -139,7 +176,7 @@ bool ModelChecker::assert_bug(const char *msg, ...)
 	vsnprintf(str, sizeof(str), msg, ap);
 	va_end(ap);
 
-	return execution->assert_bug(str);
+	execution->assert_bug(str);
 }
 
 /**
@@ -150,8 +187,8 @@ bool ModelChecker::assert_bug(const char *msg, ...)
 void ModelChecker::assert_user_bug(const char *msg)
 {
 	/* If feasible bug, bail out now */
-	if (assert_bug(msg))
-		switch_to_master(NULL);
+	assert_bug(msg);
+	switch_to_master(NULL);
 }
 
 /** @brief Print bug report listing for this execution (if any bugs exist) */
@@ -175,15 +212,12 @@ void ModelChecker::print_bugs() const
 void ModelChecker::record_stats()
 {
 	stats.num_total ++;
-	if (!execution->isfeasibleprefix())
-		stats.num_infeasible ++;
-	else if (execution->have_bug_reports())
+	if (execution->have_bug_reports())
 		stats.num_buggy_executions ++;
 	else if (execution->is_complete_execution())
 		stats.num_complete ++;
 	else {
-		stats.num_redundant ++;
-
+		//All threads are sleeping
 		/**
 		 * @todo We can violate this ASSERT() when fairness/sleep sets
 		 * conflict to cause an execution to terminate, e.g. with:
@@ -197,9 +231,7 @@ void ModelChecker::record_stats()
 void ModelChecker::print_stats() const
 {
 	model_print("Number of complete, bug-free executions: %d\n", stats.num_complete);
-	model_print("Number of redundant executions: %d\n", stats.num_redundant);
 	model_print("Number of buggy executions: %d\n", stats.num_buggy_executions);
-	model_print("Number of infeasible executions: %d\n", stats.num_infeasible);
 	model_print("Total executions: %d\n", stats.num_total);
 }
 
@@ -234,12 +266,11 @@ void ModelChecker::print_execution(bool printbugs) const
  * @return If there are more executions to explore, return true. Otherwise,
  * return false.
  */
-bool ModelChecker::next_execution()
+void ModelChecker::finish_execution(bool more_executions)
 {
 	DBG();
 	/* Is this execution a feasible execution that's worth bug-checking? */
-	bool complete = execution->isfeasibleprefix() &&
-									(execution->is_complete_execution() ||
+	bool complete = (execution->is_complete_execution() ||
 									 execution->have_bug_reports());
 
 	/* End-of-execution bug checks */
@@ -257,14 +288,12 @@ bool ModelChecker::next_execution()
 	else
 		clear_program_output();
 
-	if (restart_flag) {
-		do_restart();
-		return true;
-	}
 // test code
 	execution_number ++;
-	reset_to_initial_state();
-	return false;
+	if (more_executions)
+		reset_to_initial_state();
+
+	history->set_new_exec_flag();
 }
 
 /** @brief Run trace analyses on complete trace */
@@ -353,16 +382,16 @@ static void runChecker() {
 
 void ModelChecker::startChecker() {
 	startExecution(get_system_context(), runChecker);
-	snapshot_stack_init();
-	snapshot_record(0);
+	snapshot = take_snapshot();
+
+	install_trace_analyses(get_execution());
+	redirect_output();
+	initMainThread();
 }
 
 bool ModelChecker::should_terminate_execution()
 {
-	/* Infeasible -> don't take any more steps */
-	if (execution->is_infeasible())
-		return true;
-	else if (execution->isfeasibleprefix() && execution->have_fatal_bug_reports()) {
+	if (execution->have_bug_reports()) {
 		execution->set_assert();
 		return true;
 	} else if (execution->isFinished()) {
@@ -371,38 +400,25 @@ bool ModelChecker::should_terminate_execution()
 	return false;
 }
 
-/** @brief Restart ModelChecker upon returning to the run loop of the
- *	model checker. */
-void ModelChecker::restart()
-{
-	restart_flag = true;
-}
-
-void ModelChecker::do_restart()
-{
-	restart_flag = false;
-	reset_to_initial_state();
-	memset(&stats,0,sizeof(struct execution_stats));
-	execution_number = 1;
-}
-
-void ModelChecker::startMainThread() {
-	init_thread->set_state(THREAD_RUNNING);
-	scheduler->set_current_thread(init_thread);
-	main_thread_startup();
-}
-
 /** @brief Run ModelChecker for the user program */
 void ModelChecker::run()
 {
 	//Need to initial random number generator state to avoid resets on rollback
 	char random_state[256];
 	initstate(423121, random_state, sizeof(random_state));
-
+	modelclock_t checkfree = params.checkthreshold;
 	for(int exec = 0;exec < params.maxexecutions;exec++) {
 		Thread * t = init_thread;
 
 		do {
+			/* Check whether we need to free model actions. */
+
+			if (params.traceminsize != 0 &&
+					execution->get_curr_seq_num() > checkfree) {
+				checkfree += params.checkthreshold;
+				execution->collectActions();
+			}
+
 			/*
 			 * Stash next pending action(s) for thread(s). There
 			 * should only need to stash one thread's action--the
@@ -412,8 +428,8 @@ void ModelChecker::run()
 			for (unsigned int i = 0;i < get_num_threads();i++) {
 				thread_id_t tid = int_to_id(i);
 				Thread *thr = get_thread(tid);
-				if (!thr->is_model_thread() && !thr->is_complete() && (!thr->get_pending())) {
-					switch_from_master(thr);	// L: context swapped, and action type of thr changed.
+				if (!thr->is_model_thread() && !thr->is_complete() && !thr->get_pending()) {
+					switch_from_master(thr);
 					if (thr->is_waiting_on(thr))
 						assert_bug("Deadlock detected (thread %u)", i);
 				}
@@ -458,13 +474,19 @@ void ModelChecker::run()
 				t = get_next_thread();
 			if (!t || t->is_model_thread())
 				break;
+			if (t->just_woken_up()) {
+				t->set_wakeup_state(false);
+				t->set_pending(NULL);
+				t = NULL;
+				continue;	// Allow this thread to stash the next pending action
+			}
 
 			/* Consume the next action for a Thread */
 			ModelAction *curr = t->get_pending();
 			t->set_pending(NULL);
 			t = execution->take_step(curr);
 		} while (!should_terminate_execution());
-		next_execution();
+		finish_execution((exec+1) < params.maxexecutions);
 		//restore random number generator state after rollback
 		setstate(random_state);
 	}
@@ -475,4 +497,9 @@ void ModelChecker::run()
 	/* Have the trace analyses dump their output. */
 	for (unsigned int i = 0;i < trace_analyses.size();i++)
 		trace_analyses[i]->finish();
+
+	/* unlink tmp file created by last child process */
+	char filename[256];
+	snprintf_(filename, sizeof(filename), "C11FuzzerTmp%d", getpid());
+	unlink(filename);
 }