kernel_optimize_test/kernel/printk/braille.c
Chuhong Yuan 35c35493b0 printk: Replace strncmp() with str_has_prefix()
strncmp(str, const, len) is error-prone because len is easy to have typo.
An 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() to make code better.

Link: http://lkml.kernel.org/r/20190809071034.17279-1-hslester96@gmail.com
Cc: "Steven Rostedt" <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Reviewed-by:  Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[pmladek@suse.com: Slightly updated and reformatted the commit message.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-08-16 09:54:08 +02:00

59 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/console.h>
#include <linux/errno.h>
#include <linux/string.h>
#include "console_cmdline.h"
#include "braille.h"
int _braille_console_setup(char **str, char **brl_options)
{
size_t len;
len = str_has_prefix(*str, "brl,");
if (len) {
*brl_options = "";
*str += len;
return 0;
}
len = str_has_prefix(*str, "brl=");
if (len) {
*brl_options = *str + len;
*str = strchr(*brl_options, ',');
if (!*str) {
pr_err("need port name after brl=\n");
return -EINVAL;
}
*((*str)++) = 0;
}
return 0;
}
int
_braille_register_console(struct console *console, struct console_cmdline *c)
{
int rtn = 0;
if (c->brl_options) {
console->flags |= CON_BRL;
rtn = braille_register_console(console, c->index, c->options,
c->brl_options);
}
return rtn;
}
int
_braille_unregister_console(struct console *console)
{
if (console->flags & CON_BRL)
return braille_unregister_console(console);
return 0;
}