Add blkdev_skip_space() and blkdev_find_space() for parsing writes to
sysfs attributes

Add blkdev_read_mode() and blkdev_write_mode() LED comparison helpers

Signed-off-by: Ian Pilcher <redacted>
---
 drivers/leds/trigger/ledtrig-blkdev.c | 44 +++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/drivers/leds/trigger/ledtrig-blkdev.c b/drivers/leds/trigger/ledtrig-blkdev.c
index db8326874400..1f319529c3be 100644
--- a/drivers/leds/trigger/ledtrig-blkdev.c
+++ b/drivers/leds/trigger/ledtrig-blkdev.c

@@ -6,6 +6,7 @@
  *	Copyright 2021 Ian Pilcher <arequipeno@gmail.com>
  */
 
+#include <linux/ctype.h>
 #include <linux/module.h>
 
 #include "ledtrig-blkdev.h"

@@ -66,3 +67,46 @@ static unsigned int ledtrig_blkdev_count;
 
 /* How often to check for drive activity - in jiffies */
 static unsigned int ledtrig_blkdev_interval;
+
+
+/*
+ *
+ *	Miscellaneous helper functions
+ *
+ */
+
+/*
+ * Returns a pointer to the first non-whitespace character in s
+ * (or a pointer to the terminating null).
+ */
+static const char *blkdev_skip_space(const char *s)
+{
+	while (*s != 0 && isspace(*s))
+		++s;
+
+	return s;
+}
+
+/*
+ * Returns a pointer to the first whitespace character in s (or a pointer to the
+ * terminating null), which is effectively a pointer to the position *after* the
+ * last character in the non-whitespace token at the beginning of s.  (s is
+ * expected to be the result of a previous call to blkdev_skip_space()).
+ */
+static const char *blkdev_find_space(const char *s)
+{
+	while (*s != 0 && !isspace(*s))
+		++s;
+
+	return s;
+}