Re: [PATHCv10 1/2] usb: USB Type-C connector class

[Heikki Krogerus]

Hi Greg,

On Mon, Nov 14, 2016 at 10:51:48AM +0100, Greg KH wrote:
> > +static int sysfs_strmatch(const char * const *array, size_t n, const char *str)
> > +{
> > +	const char *item;
> > +	int index;
> > +
> > +	for (index = 0; index < n; index++) {
> > +		item = array[index];
> > +		if (!item)
> > +			break;
> > +		if (sysfs_streq(item, str))
> > +			return index;
> > +	}
> > +
> > +	return -EINVAL;
> > +}
> 
> should we make this a core sysfs function?

Last question before I send v11. Is the following (the helper) OK?


diff --git a/include/linux/string.h b/include/linux/string.h
index 26b6f6a..5606810 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -135,6 +135,16 @@ static inline int strtobool(const char *s, bool *res)
 }
 
 int match_string(const char * const *array, size_t n, const char *string);
+int __sysfs_strmatch(const char * const *array, size_t n, const char *string);
+
+/**
+ * sysfs_strmatch - matches given string in an array
+ * @a: array of strings
+ * @s: string to match with
+ *
+ * Helper for __sysfs_strmatch(). Calculates the size of @a automatically.
+ */
+#define sysfs_strmatch(a, s) __sysfs_strmatch(a, ARRAY_SIZE(a), s)
 
 #ifdef CONFIG_BINARY_PRINTF
 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args);
diff --git a/lib/string.c b/lib/string.c
index ed83562..a4fe035 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -656,6 +656,32 @@ int match_string(const char * const *array, size_t n, const char *string)
 }
 EXPORT_SYMBOL(match_string);
 
+/**
+ * __sysfs_strmatch - matches given string in an array
+ * @array: array of strings
+ * @n: number of strings in the array or -1 for NULL terminated arrays
+ * @str: string to match with
+ *
+ * Returns index of @str in the @array or -EINVAL, just like match_string().
+ * Uses sysfs_streq() instead of strcmp for matching.
+ */
+int __sysfs_strmatch(const char * const *array, size_t n, const char *str)
+{
+       const char *item;
+       int index;
+
+       for (index = 0; index < n; index++) {
+               item = array[index];
+               if (!item)
+                       break;
+               if (!sysfs_streq(item, str))
+                       return index;
+       }
+
+       return -EINVAL;
+}
+EXPORT_SYMBOL(__sysfs_strmatch);
+
 #ifndef __HAVE_ARCH_MEMSET
 /**
  * memset - Fill a region of memory with the given value


-- 
heikki