Make enum process_status enumerators uppercase

Rationale: coding style consistency.
diff --git a/sysdeps/linux-gnu/events.c b/sysdeps/linux-gnu/events.c
index 52e2f4f..71d99b6 100644
--- a/sysdeps/linux-gnu/events.c
+++ b/sysdeps/linux-gnu/events.c
@@ -188,7 +188,7 @@
 		 * now) the pain of figuring this out all over again.
 		 * Petr Machata 2011-11-22.  */
 		int i = 0;
-		for (; i < 100 && process_status(pid) != ps_tracing_stop; ++i) {
+		for (; i < 100 && process_status(pid) != PS_TRACING_STOP; ++i) {
 			debug(2, "waiting for %d to stop", pid);
 			usleep(10000);
 		}
diff --git a/sysdeps/linux-gnu/proc.c b/sysdeps/linux-gnu/proc.c
index 9f6ef2c..6e01d28 100644
--- a/sysdeps/linux-gnu/proc.c
+++ b/sysdeps/linux-gnu/proc.c
@@ -177,44 +177,45 @@
 	} while (0)
 
 	switch (c) {
-	case 'Z': RETURN(ps_zombie);
-	case 't': RETURN(ps_tracing_stop);
+	case 'Z': RETURN(PS_ZOMBIE);
+	case 't': RETURN(PS_TRACING_STOP);
 	case 'T':
 		/* This can be either "T (stopped)" or, for older
 		 * kernels, "T (tracing stop)".  */
 		if (!strcmp(status, "T (stopped)\n"))
-			RETURN(ps_stop);
+			RETURN(PS_STOP);
 		else if (!strcmp(status, "T (tracing stop)\n"))
-			RETURN(ps_tracing_stop);
+			RETURN(PS_TRACING_STOP);
 		else {
 			fprintf(stderr, "Unknown process status: %s",
 				status);
-			RETURN(ps_stop); /* Some sort of stop
+			RETURN(PS_STOP); /* Some sort of stop
 					  * anyway.  */
 		}
 	case 'D':
-	case 'S': RETURN(ps_sleeping);
+	case 'S': RETURN(PS_SLEEPING);
 	}
 
-	RETURN(ps_other);
+	RETURN(PS_OTHER);
 #undef RETURN
 }
 
 enum process_status
 process_status(pid_t pid)
 {
-	enum process_status ret = ps_invalid;
+	enum process_status ret = PS_INVALID;
 	FILE * file = open_status_file(pid);
 	if (file != NULL) {
 		each_line_starting(file, "State:\t", &process_status_cb, &ret);
 		fclose(file);
-		if (ret == ps_invalid)
+		if (ret == PS_INVALID)
 			fprintf(stderr, "process_status %d: %s", pid,
 				strerror(errno));
-	} else
+	} else {
 		/* If the file is not present, the process presumably
 		 * exited already.  */
-		ret = ps_zombie;
+		ret = PS_ZOMBIE;
+	}
 
 	return ret;
 }
diff --git a/sysdeps/linux-gnu/trace.c b/sysdeps/linux-gnu/trace.c
index 77dfade..42dd4d9 100644
--- a/sysdeps/linux-gnu/trace.c
+++ b/sysdeps/linux-gnu/trace.c
@@ -217,13 +217,13 @@
 	 * the meantime.  This can happen when the whole thread group
 	 * is terminating.  */
 	switch (st) {
-	case ps_invalid:
-	case ps_tracing_stop:
-	case ps_zombie:
+	case PS_INVALID:
+	case PS_TRACING_STOP:
+	case PS_ZOMBIE:
 		return CBS_CONT;
-	case ps_sleeping:
-	case ps_stop:
-	case ps_other:
+	case PS_SLEEPING:
+	case PS_STOP:
+	case PS_OTHER:
 		return CBS_STOP;
 	}
 
@@ -299,8 +299,8 @@
 	 * vforked process.  We set up event handler specially to hint
 	 * us.  In that case parent is in D state, which we use to
 	 * weed out unnecessary looping.  */
-	if (st == ps_sleeping
-	    && is_vfork_parent (task)) {
+	if (st == PS_SLEEPING
+	    && is_vfork_parent(task)) {
 		task_info->vforked = 1;
 		return CBS_CONT;
 	}