[PATCH 3/6] cpupower: Add is_sysfs_present API

[Wyes Karny]

Add is_sysfs_present API to check whether the sysfs file is present or not.

Suggested-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>
Signed-off-by: Wyes Karny <wyes.karny@xxxxxxx>
---
 tools/power/cpupower/lib/cpupower.c        | 7 +++++++
 tools/power/cpupower/lib/cpupower_intern.h | 1 +
 2 files changed, 8 insertions(+)

diff --git a/tools/power/cpupower/lib/cpupower.c b/tools/power/cpupower/lib/cpupower.c
index 3f7d0c0c5067..7a2ef691b20e 100644
--- a/tools/power/cpupower/lib/cpupower.c
+++ b/tools/power/cpupower/lib/cpupower.c
@@ -14,6 +14,13 @@
 #include "cpupower.h"
 #include "cpupower_intern.h"
 
+int is_valid_path(const char *path)
+{
+	if (access(path, F_OK) == -1)
+		return 0;
+	return 1;
+}
+
 unsigned int cpupower_read_sysfs(const char *path, char *buf, size_t buflen)
 {
 	ssize_t numread;
diff --git a/tools/power/cpupower/lib/cpupower_intern.h b/tools/power/cpupower/lib/cpupower_intern.h
index ac1112b956ec..5fdb8620d41b 100644
--- a/tools/power/cpupower/lib/cpupower_intern.h
+++ b/tools/power/cpupower/lib/cpupower_intern.h
@@ -7,5 +7,6 @@
 
 #define SYSFS_PATH_MAX 255
 
+int is_valid_path(const char *path);
 unsigned int cpupower_read_sysfs(const char *path, char *buf, size_t buflen);
 unsigned int cpupower_write_sysfs(const char *path, char *buf, size_t buflen);
-- 
2.34.1