1 files changed, 108 insertions, 0 deletions
diff --git a/fs/unicode/utf8n.h b/fs/unicode/utf8n.h
new file mode 100644
index 000000000..0acd530c2
--- /dev/null
+++ b/fs/unicode/utf8n.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2014 SGI.
+ * All rights reserved.
+ */
+
+#ifndef UTF8NORM_H
+#define UTF8NORM_H
+
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/string.h>
+#include <linux/module.h>
+
+/* Encoding a unicode version number as a single unsigned int. */
+#define UNICODE_MAJ_SHIFT		(16)
+#define UNICODE_MIN_SHIFT		(8)
+
+#define UNICODE_AGE(MAJ, MIN, REV)			\
+	(((unsigned int)(MAJ) << UNICODE_MAJ_SHIFT) |	\
+	 ((unsigned int)(MIN) << UNICODE_MIN_SHIFT) |	\
+	 ((unsigned int)(REV)))
+
+/* Highest unicode version supported by the data tables. */
+extern int utf8version_is_supported(u8 maj, u8 min, u8 rev);
+extern int utf8version_latest(void);
+
+/*
+ * Look for the correct const struct utf8data for a unicode version.
+ * Returns NULL if the version requested is too new.
+ *
+ * Two normalization forms are supported: nfdi and nfdicf.
+ *
+ * nfdi:
+ *  - Apply unicode normalization form NFD.
+ *  - Remove any Default_Ignorable_Code_Point.
+ *
+ * nfdicf:
+ *  - Apply unicode normalization form NFD.
+ *  - Remove any Default_Ignorable_Code_Point.
+ *  - Apply a full casefold (C + F).
+ */
+extern const struct utf8data *utf8nfdi(unsigned int maxage);
+extern const struct utf8data *utf8nfdicf(unsigned int maxage);
+
+/*
+ * Determine the maximum age of any unicode character in the string.
+ * Returns 0 if only unassigned code points are present.
+ * Returns -1 if the input is not valid UTF-8.
+ */
+extern int utf8agemax(const struct utf8data *data, const char *s);
+extern int utf8nagemax(const struct utf8data *data, const char *s, size_t len);
+
+/*
+ * Determine the minimum age of any unicode character in the string.
+ * Returns 0 if any unassigned code points are present.
+ * Returns -1 if the input is not valid UTF-8.
+ */
+extern int utf8agemin(const struct utf8data *data, const char *s);
+extern int utf8nagemin(const struct utf8data *data, const char *s, size_t len);
+
+/*
+ * Determine the length of the normalized from of the string,
+ * excluding any terminating NULL byte.
+ * Returns 0 if only ignorable code points are present.
+ * Returns -1 if the input is not valid UTF-8.
+ */
+extern ssize_t utf8len(const struct utf8data *data, const char *s);
+extern ssize_t utf8nlen(const struct utf8data *data, const char *s, size_t len);
+
+/* Needed in struct utf8cursor below. */
+#define UTF8HANGULLEAF	(12)
+
+/*
+ * Cursor structure used by the normalizer.
+ */
+struct utf8cursor {
+	const struct utf8data	*data;
+	const char	*s;
+	const char	*p;
+	const char	*ss;
+	const char	*sp;
+	unsigned int	len;
+	unsigned int	slen;
+	short int	ccc;
+	short int	nccc;
+	unsigned char	hangul[UTF8HANGULLEAF];
+};
+
+/*
+ * Initialize a utf8cursor to normalize a string.
+ * Returns 0 on success.
+ * Returns -1 on failure.
+ */
+extern int utf8cursor(struct utf8cursor *u8c, const struct utf8data *data,
+		      const char *s);
+extern int utf8ncursor(struct utf8cursor *u8c, const struct utf8data *data,
+		       const char *s, size_t len);
+
+/*
+ * Get the next byte in the normalization.
+ * Returns a value > 0 && < 256 on success.
+ * Returns 0 when the end of the normalization is reached.
+ * Returns -1 if the string being normalized is not valid UTF-8.
+ */
+extern int utf8byte(struct utf8cursor *u8c);
+
+#endif /* UTF8NORM_H */