tools: Clone the kernel's strtobool function
Copying it to tools/lib/string.c, the counterpart to the kernel's
lib/string.c.
This is preparation for enhancing BPF program configuration, which will
allow config string like 'inlines=yes'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-6-git-send-email-wangnan0@huawei.com
[ Copied it to tools/lib/string.c instead, to make it usable by other tools/ ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/lib/string.c b/tools/lib/string.c
index ecfd43a..065e54f 100644
--- a/tools/lib/string.c
+++ b/tools/lib/string.c
@@ -1,5 +1,20 @@
+/*
+ * linux/tools/lib/string.c
+ *
+ * Copied from linux/lib/string.c, where it is:
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * More specifically, the first copied function was strtobool, which
+ * was introduced by:
+ *
+ * d0f1fed29e6e ("Add a strtobool function matching semantics of existing in kernel equivalents")
+ * Author: Jonathan Cameron <jic23@cam.ac.uk>
+ */
+
#include <stdlib.h>
#include <string.h>
+#include <errno.h>
#include <linux/string.h>
/**
@@ -17,3 +32,31 @@
return p;
}
+
+/**
+ * strtobool - convert common user inputs into boolean values
+ * @s: input string
+ * @res: result
+ *
+ * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
+ * Otherwise it will return -EINVAL. Value pointed to by res is
+ * updated upon finding a match.
+ */
+int strtobool(const char *s, bool *res)
+{
+ switch (s[0]) {
+ case 'y':
+ case 'Y':
+ case '1':
+ *res = true;
+ break;
+ case 'n':
+ case 'N':
+ case '0':
+ *res = false;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}