[PATCH] ptp: Replace snprintf in show functions with sysfs_emit

From: Jing Yao <redacted>

coccicheck complains about the use of snprintf() in sysfs show
functions:
WARNING use scnprintf or sprintf

Use sysfs_emit instead of scnprintf, snprintf or sprintf makes more
sense.

Reported-by: Zeal Robot <redacted>
Signed-off-by: Jing Yao <redacted>
---
 drivers/ptp/ptp_sysfs.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index 41b92dc2f011..867435df912a 100644
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c

@@ -86,7 +86,7 @@ static ssize_t extts_fifo_show(struct device *dev,
 	if (!qcnt)
 		goto out;
 
-	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
+	cnt = sysfs_emit(page, "%u %lld %u\n",
 		       event.index, event.t.sec, event.t.nsec);
 out:
 	mutex_unlock(&ptp->tsevq_mux);

@@ -387,7 +387,7 @@ static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
 
 	mutex_unlock(&ptp->pincfg_mux);
 
-	return snprintf(page, PAGE_SIZE, "%u %u\n", func, chan);
+	return sysfs_emit(page, "%u %u\n", func, chan);
 }
 
 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,

-- 
2.25.1

On Wed, 2021-11-10 at 02:23 +0000, cgel.zte@gmail.com wrote:

From: Jing Yao <redacted>

coccicheck complains about the use of snprintf() in sysfs show
functions:
WARNING use scnprintf or sprintf

Use sysfs_emit instead of scnprintf, snprintf or sprintf makes more
sense.

[]

Reported-by: Zeal Robot <redacted>
Signed-off-by: Jing Yao <redacted>

[]

[]

If you are going to try to fix these, please do try to fix all of
the instances in the same file.

So here's a macro definition from that file used multiple times:

static ssize_t var##_show(struct device *dev,				\
			   struct device_attribute *attr, char *page)	\
{									\
	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);	\
}									\
static DEVICE_ATTR(name, 0444, var##_show, NULL);

and another function:

static ssize_t n_vclocks_show(struct device *dev,
			      struct device_attribute *attr, char *page)
{
	struct ptp_clock *ptp = dev_get_drvdata(dev);
	ssize_t size;

	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
		return -ERESTARTSYS;

	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);

	mutex_unlock(&ptp->n_vclocks_mux);

	return size;
}

and yet another function:

static ssize_t max_vclocks_show(struct device *dev,
				struct device_attribute *attr, char *page)
{
	struct ptp_clock *ptp = dev_get_drvdata(dev);
	ssize_t size;

	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);

	return size;
}