Re: [PATCH] staging: replace snprintf with sysfs_emit

[Joe Perches]

On Tue, 2021-11-30 at 08:07 +0800, davidcomponentone@xxxxxxxxx wrote:
> From: Yang Guang <yang.guang5@xxxxxxxxxx>
> 
> coccinelle report:
> ./drivers/staging/fieldbus/dev_core.c:73:8-16:
> WARNING: use scnprintf or sprintf
> 
> Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Please convert all the show functions and not just 1 of the 6 possible
cases.

> diff --git a/drivers/staging/fieldbus/dev_core.c b/drivers/staging/fieldbus/dev_core.c
[]
> @@ -70,7 +70,7 @@ static ssize_t card_name_show(struct device *dev, struct device_attribute *attr,
>  	 * card_name was provided by child driver, could potentially be long.
>  	 * protect against buffer overrun.
>  	 */
> -	return snprintf(buf, PAGE_SIZE, "%s\n", fb->card_name);
> +	return sysfs_emit(buf, "%s\n", fb->card_name);
>  }
>  static DEVICE_ATTR_RO(card_name);
>  

---
 drivers/staging/fieldbus/dev_core.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/fieldbus/dev_core.c b/drivers/staging/fieldbus/dev_core.c
index 5aab734606eae..9c85bf87a8d7f 100644
--- a/drivers/staging/fieldbus/dev_core.c
+++ b/drivers/staging/fieldbus/dev_core.c
@@ -28,7 +28,7 @@ static ssize_t online_show(struct device *dev, struct device_attribute *attr,
 {
 	struct fieldbus_dev *fb = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%d\n", !!fb->online);
+	return sysfs_emit(buf, "%d\n", !!fb->online);
 }
 static DEVICE_ATTR_RO(online);
 
@@ -39,7 +39,7 @@ static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
 
 	if (!fb->enable_get)
 		return -EINVAL;
-	return sprintf(buf, "%d\n", !!fb->enable_get(fb));
+	return sysfs_emit(buf, "%d\n", !!fb->enable_get(fb));
 }
 
 static ssize_t enabled_store(struct device *dev, struct device_attribute *attr,
@@ -70,7 +70,7 @@ static ssize_t card_name_show(struct device *dev, struct device_attribute *attr,
 	 * card_name was provided by child driver, could potentially be long.
 	 * protect against buffer overrun.
 	 */
-	return snprintf(buf, PAGE_SIZE, "%s\n", fb->card_name);
+	return sysfs_emit(buf, "%s\n", fb->card_name);
 }
 static DEVICE_ATTR_RO(card_name);
 
@@ -79,7 +79,7 @@ static ssize_t read_area_size_show(struct device *dev,
 {
 	struct fieldbus_dev *fb = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%zu\n", fb->read_area_sz);
+	return sysfs_emit(buf, "%zu\n", fb->read_area_sz);
 }
 static DEVICE_ATTR_RO(read_area_size);
 
@@ -88,7 +88,7 @@ static ssize_t write_area_size_show(struct device *dev,
 {
 	struct fieldbus_dev *fb = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%zu\n", fb->write_area_sz);
+	return sysfs_emit(buf, "%zu\n", fb->write_area_sz);
 }
 static DEVICE_ATTR_RO(write_area_size);
 
@@ -116,7 +116,7 @@ static ssize_t fieldbus_type_show(struct device *dev,
 		break;
 	}
 
-	return sprintf(buf, "%s\n", t);
+	return sysfs_emit(buf, "%s\n", t);
 }
 static DEVICE_ATTR_RO(fieldbus_type);