From 5563cc1c6bda21eb917f6bfd0c606e7f55f33eec Mon Sep 17 00:00:00 2001
From: Bahadir Balban <bbalban@b-labs.co.uk>
Date: Fri, 18 Apr 2008 01:03:39 +0100
Subject: [PATCH] Minor changes on sys_time

A get/set flag determines whether to read or write time.
---
 src/generic/time.c                            | 41 ++++++++++++-------
 tasks/fs0/main.c                              | 10 +++++
 tasks/libl4/include/l4lib/arch-arm/syscalls.h | 12 +++++-
 3 files changed, 47 insertions(+), 16 deletions(-)

diff --git a/src/generic/time.c b/src/generic/time.c
index 46f1cdb..2e6db8d 100644
--- a/src/generic/time.c
+++ b/src/generic/time.c
@@ -76,28 +76,39 @@ void update_system_time(void)
 int sys_time(struct syscall_args *args)
 {
        	struct time_info *ti = (struct time_info *)args->r0;
+	int set = (int)args->r1;
 	int retries = 20;
 
 	if (check_access((unsigned long)ti, sizeof(*ti), MAP_USR_RW_FLAGS) < 0)
 		return -EINVAL;
 
-	while(retries > 0) {
-		systime.reader = 1;
-		memcpy(ti, &systime, sizeof(*ti));
-		retries--;
+	/* Get time */
+	if (!set) {
+		while(retries > 0) {
+			systime.reader = 1;
+			memcpy(ti, &systime, sizeof(*ti));
+			retries--;
 
-		if (systime.reader)
-			break;
+			if (systime.reader)
+				break;
+		}
+
+		/*
+		 * No need to reset reader since it will be reset
+		 * on next timer. If no retries return busy.
+		 */
+		if (!retries)
+			return -EBUSY;
+		else
+			return 0;
+
+	/* Set */
+	} else {
+		/*
+		 * Setting the time not supported yet.
+		 */
+		return -ENOSYS;
 	}
-
-	/*
-	 * No need to reset reader since it will be reset
-	 * on next timer. If no retries return busy.
-	 */
-	if (!retries)
-		return -EBUSY;
-	else
-		return 0;
 }
 
 void update_process_times(void)
diff --git a/tasks/fs0/main.c b/tasks/fs0/main.c
index 155e858..bc087f3 100644
--- a/tasks/fs0/main.c
+++ b/tasks/fs0/main.c
@@ -99,12 +99,22 @@ void handle_fs_requests(void)
 
 void main(void)
 {
+	struct time_info ti;
+
 	printf("\n%s: Started with tid: %d\n", __TASKNAME__, self_tid());
 
 	initialise();
 
 	wait_pager(PAGER_TID);
 
+	if (l4_time(&ti, 0) < 0) {
+		printf("Reading the time has failed.\n");
+	} else {
+		printf("Current time since system started: %u ticks, "
+		       "%u seconds, %u minutes, %u hours, %llu days.\n",
+		       ti.thz, ti.sec, ti.min, ti.hour, ti.day);
+	}
+
 	printf("%s: Listening requests.\n", __TASKNAME__);
 	while (1) {
 		handle_fs_requests();
diff --git a/tasks/libl4/include/l4lib/arch-arm/syscalls.h b/tasks/libl4/include/l4lib/arch-arm/syscalls.h
index 05e645f..4155400 100644
--- a/tasks/libl4/include/l4lib/arch-arm/syscalls.h
+++ b/tasks/libl4/include/l4lib/arch-arm/syscalls.h
@@ -68,7 +68,17 @@ typedef int (*__l4_kmem_control_t)(unsigned long pfn, int npages, int grant);
 extern __l4_kmem_control_t __l4_kmem_control;
 int l4_kmem_control(unsigned long pfn, int npages, int grant);
 
-typedef int (*__l4_time_t)(void *time_info, int set);
+/* Represents time since epoch, a c0 specific structure. */
+struct time_info {
+	int reader;
+	u32 thz;	/* Ticks in this hertz so far */
+	u32 sec;
+	u32 min;
+	u32 hour;
+	u64 day;
+};
+
+typedef int (*__l4_time_t)(struct time_info *ti, int set);
 extern __l4_time_t __l4_time;
 int l4_time(void *time_info, int set);