v4.19.13 snapshot.
diff --git a/tools/include/linux/string.h b/tools/include/linux/string.h
new file mode 100644
index 0000000..6c3e2cc
--- /dev/null
+++ b/tools/include/linux/string.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _TOOLS_LINUX_STRING_H_
+#define _TOOLS_LINUX_STRING_H_
+
+#include <linux/types.h> /* for size_t */
+#include <string.h>
+
+void *memdup(const void *src, size_t len);
+
+int strtobool(const char *s, bool *res);
+
+/*
+ * glibc based builds needs the extern while uClibc doesn't.
+ * However uClibc headers also define __GLIBC__ hence the hack below
+ */
+#if defined(__GLIBC__) && !defined(__UCLIBC__)
+extern size_t strlcpy(char *dest, const char *src, size_t size);
+#endif
+
+char *str_error_r(int errnum, char *buf, size_t buflen);
+
+/**
+ * strstarts - does @str start with @prefix?
+ * @str: string to examine
+ * @prefix: prefix to look for.
+ */
+static inline bool strstarts(const char *str, const char *prefix)
+{
+ return strncmp(str, prefix, strlen(prefix)) == 0;
+}
+
+#endif /* _LINUX_STRING_H_ */