cpupower:Fix resource leaks in sysfs_get_enabled()

The sysfs_get_enabled() opened file processor not closed,
may cause a file handle leak.
Putting error handling and resource cleanup code together
makes the code easy to maintain and read.
Removed the unnecessary else if branch from the original
function, as it should return an error in cases other than '0'.

Signed-off-by: Hao Zeng <zenghao@kylinos.cn>
Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

diff --git a/tools/power/cpupower/lib/powercap.c b/tools/power/cpupower/lib/powercap.c
index 0ce29ee4c2e4634592bb3ec993ab26988ca80d8c..a7a59c6bacda81644d72c3023ad824365bfb33f5 100644 (file)
--- a/tools/power/cpupower/lib/powercap.c
+++ b/tools/power/cpupower/lib/powercap.c
@@ -40,25 +40,34 @@ static int sysfs_get_enabled(char *path, int *mode)
 {
        int fd;
        char yes_no;
+       int ret = 0;
 
        *mode = 0;
 
        fd = open(path, O_RDONLY);
-       if (fd == -1)
-               return -1;
+       if (fd == -1) {
+               ret = -1;
+               goto out;
+       }
 
        if (read(fd, &yes_no, 1) != 1) {
-               close(fd);
-               return -1;
+               ret = -1;
+               goto out_close;
        }
 
        if (yes_no == '1') {
                *mode = 1;
-               return 0;
+               goto out_close;
        } else if (yes_no == '0') {
-               return 0;
+               goto out_close;
+       } else {
+               ret = -1;
+               goto out_close;
        }
-       return -1;
+out_close:
+       close(fd);
+out:
+       return ret;
 }
 
 int powercap_get_enabled(int *mode)