[PATCH v2 07/10] reboot: Replace strncmp with str_has_prefix

[Chuhong Yuan]

strncmp(str, const, len) is error-prone because len
is easy to have typo.
The example is the hard-coded len has counting error
or sizeof(const) forgets - 1.
So we prefer using newly introduced str_has_prefix
to substitute such strncmp.

Signed-off-by: Chuhong Yuan <hsleste...@gmail.com>
---
Changes in v2:
  - Revise the description.
  - Utilize str_has_prefix's return value to
    eliminate some hard codes.

 kernel/reboot.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/reboot.c b/kernel/reboot.c
index c4d472b7f1b4..addb52391177 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -520,6 +520,8 @@ EXPORT_SYMBOL_GPL(orderly_reboot);
 
 static int __init reboot_setup(char *str)
 {
+       size_t len;
+
        for (;;) {
                enum reboot_mode *mode;
 
@@ -530,9 +532,9 @@ static int __init reboot_setup(char *str)
                 */
                reboot_default = 0;
 
-               if (!strncmp(str, "panic_", 6)) {
+               if ((len = str_has_prefix(str, "panic_"))) {
                        mode = &panic_reboot_mode;
-                       str += 6;
+                       str += len;
                } else {
                        mode = &reboot_mode;
                }
-- 
2.20.1