tools lib api fs: Introduce sysfs__read_bool

Will be used in a upcoming patch warning about PERF_RECORD_AUX data gaps, reading the "module/kvm_intel/parameters/vmm_exclusive" sysfs entry. Signed-off-by: Alexander Shishkin <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Vince Weaver <[email protected]> Link: http://lkml.kernel.org/r/[email protected] [ split from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
kyagi · Mar 17, 2017 · b9835a9 · b9835a9
1 parent f371594
commit b9835a9
Show file tree

Hide file tree

Showing 2 changed files with 30 additions and 0 deletions.
diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c
@@ -439,6 +439,35 @@ int sysfs__read_str(const char *entry, char **buf, size_t *sizep)
 	return filename__read_str(path, buf, sizep);
 }
 
+int sysfs__read_bool(const char *entry, bool *value)
+{
+	char *buf;
+	size_t size;
+	int ret;
+
+	ret = sysfs__read_str(entry, &buf, &size);
+	if (ret < 0)
+		return ret;
+
+	switch (buf[0]) {
+	case '1':
+	case 'y':
+	case 'Y':
+		*value = true;
+		break;
+	case '0':
+	case 'n':
+	case 'N':
+		*value = false;
+		break;
+	default:
+		ret = -1;
+	}
+
+	free(buf);
+
+	return ret;
+}
 int sysctl__read_int(const char *sysctl, int *value)
 {
 	char path[PATH_MAX];

diff --git a/tools/lib/api/fs/fs.h b/tools/lib/api/fs/fs.h
@@ -37,4 +37,5 @@ int sysctl__read_int(const char *sysctl, int *value);
 int sysfs__read_int(const char *entry, int *value);
 int sysfs__read_ull(const char *entry, unsigned long long *value);
 int sysfs__read_str(const char *entry, char **buf, size_t *sizep);
+int sysfs__read_bool(const char *entry, bool *value);
 #endif /* __API_FS__ */