[PATCH] leds: Avoid needless strlen() for attributes

From: Sven Wegener
Date: Fri Aug 01 2008 - 16:30:44 EST


There's no need for the additional call to strlen(), we can directly return the
value returned by sprintf(). We now return a length value that doesn't include
the final '\0', but user space shouldn't bother about it anyway.

Signed-off-by: Sven Wegener <sven.wegener@xxxxxxxxxxx>
---
drivers/leds/led-class.c | 5 +----
drivers/leds/ledtrig-timer.c | 8 ++------
2 files changed, 3 insertions(+), 10 deletions(-)

Patch is based on your current (024e8ac) leds git tree head.

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 559a408..1aa24d3 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -34,14 +34,11 @@ static ssize_t led_brightness_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
- ssize_t ret = 0;

/* no lock needed for this */
led_update_brightness(led_cdev);
- sprintf(buf, "%u\n", led_cdev->brightness);
- ret = strlen(buf) + 1;

- return ret;
+ return sprintf(buf, "%u\n", led_cdev->brightness);
}

static ssize_t led_brightness_store(struct device *dev,
diff --git a/drivers/leds/ledtrig-timer.c b/drivers/leds/ledtrig-timer.c
index 5c99f4f..db68196 100644
--- a/drivers/leds/ledtrig-timer.c
+++ b/drivers/leds/ledtrig-timer.c
@@ -70,9 +70,7 @@ static ssize_t led_delay_on_show(struct device *dev,
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;

- sprintf(buf, "%lu\n", timer_data->delay_on);
-
- return strlen(buf) + 1;
+ return sprintf(buf, "%lu\n", timer_data->delay_on);
}

static ssize_t led_delay_on_store(struct device *dev,
@@ -116,9 +114,7 @@ static ssize_t led_delay_off_show(struct device *dev,
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct timer_trig_data *timer_data = led_cdev->trigger_data;

- sprintf(buf, "%lu\n", timer_data->delay_off);
-
- return strlen(buf) + 1;
+ return sprintf(buf, "%lu\n", timer_data->delay_off);
}

static ssize_t led_delay_off_store(struct device *dev,
--
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