assert: use abort() instead of exit()

- atexit functions should not be called
- stream synchronization is optional (might lead to deadlocks)
- the exit code should indicate the program was killed with SIGABRT

JIRA: RTOS-668

include/assert.h

@@ -28,9 +28,7 @@ extern "C" {
 
 #ifndef NDEBUG
 #define assert(__expr) \
-    ((__expr) \
-     ? (void)0 \
-     : ({ printf("Assertion '%s' failed in file %s:%d, function %s.\n", #__expr, __FILE__, __LINE__, __func__); exit(1);}))
+	((__expr) ? (void)0 : ({ printf("Assertion '%s' failed in file %s:%d, function %s.\n", #__expr, __FILE__, __LINE__, __func__); abort(); }))
 #else
 
 

include/stdlib.h

@@ -122,7 +122,7 @@ extern size_t malloc_usable_size(void *ptr);
 
 
 /* Causes an abnormal program termination. */
-extern void abort(void);
+extern void abort(void) __attribute__((__noreturn__));
 
 
 /* Causes the specified function func to be called when the program terminates normally. */

stdlib/abort.c

@@ -5,19 +5,33 @@
  *
  * abort.c
  *
- * Copyright 2018 Phoenix Systems
- * Author: Kamil Amanowicz
+ * Copyright 2018,2023 Phoenix Systems
+ * Author: Kamil Amanowicz, Marek Bialowas
  *
  * This file is part of Phoenix-RTOS.
  *
  * %LICENSE%
  */
 #include <stdlib.h>
 #include <signal.h>
+#include <unistd.h>
 
 void abort(void)
 {
+	/* unblock SIGABRT */
+	sigset_t sigs;
+	sigemptyset(&sigs);
+	sigaddset(&sigs, SIGABRT);
+	sigprocmask(SIG_UNBLOCK, &sigs, NULL);
+
+	raise(SIGABRT);
+
+	/* should not return even for user-specified signal handler, but retry with default handler */
+	signal(SIGABRT, SIG_DFL);
 	raise(SIGABRT);
-	while(1)
-		exit(EXIT_FAILURE);
+
+	/* should not return, finish program however we can */
+	for (;;) {
+		_exit(127);
+	}
 }