[dpdk-dev] [PATCH v3 1/2] power: fix power management env detection

[Anatoly Burakov]

Anything coming from sysfs has a newline at the end. Cut it off before
comparing the strings.

Fixes: 20ab67608a39 ("power: add environment capability probing")

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
Acked-by: David Hunt <david.hunt at intel.com>
---

Notes:
    v3:
    - Check if last character is really a newline before removing it
    
    v2:
    - Fix potential integer underflow

 lib/librte_power/power_common.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/librte_power/power_common.c b/lib/librte_power/power_common.c
index 59023d986b..67e3318ec7 100644
--- a/lib/librte_power/power_common.c
+++ b/lib/librte_power/power_common.c
@@ -17,6 +17,7 @@ cpufreq_check_scaling_driver(const char *driver_name)
 	unsigned int lcore_id = 0; /* always check core 0 */
 	char fullpath[PATH_MAX];
 	char readbuf[PATH_MAX];
+	size_t end_idx;
 	char *s;
 	FILE *f;
 
@@ -39,6 +40,13 @@ cpufreq_check_scaling_driver(const char *driver_name)
 	if (s == NULL)
 		return 0;
 
+	/* when read from sysfs, driver name has an extra newline at the end */
+	end_idx = strnlen(readbuf, sizeof(readbuf));
+	if (end_idx > 0 && readbuf[end_idx - 1] == '\n') {
+		end_idx--;
+		readbuf[end_idx] = '\0';
+	}
+
 	/* does the driver name match? */
 	if (strncmp(readbuf, driver_name, sizeof(readbuf)) != 0)
 		return 0;
-- 
2.17.1