1 files changed, 150 insertions, 0 deletions
diff --git a/regexp/utf8.h b/regexp/utf8.h
new file mode 100644
index 000000000..99706839a
--- /dev/null
+++ b/regexp/utf8.h
@@ -0,0 +1,150 @@
+#ifndef UTF8_UTIL_H
+#define UTF8_UTIL_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * UTF-8 utility functions
+ *
+ * (c) 2010-2016 Steve Bennett <[email protected]>
+ *
+ * See LICENCE for licence details.
+ */
+#include <jim-config.h>
+
+/* Currently we support unicode points up to 2^22-1 */
+#define MAX_UTF8_LEN 4
+
+/**
+ * Converts the given unicode codepoint (0 - 0x1fffff) to utf-8
+ * and stores the result at 'p'.
+ *
+ * Returns the number of utf-8 characters (up to MAX_UTF8_LEN).
+ */
+int utf8_fromunicode(char *p, unsigned uc);
+
+#ifndef JIM_UTF8
+#include <ctype.h>
+
+/* No utf-8 support. 1 byte = 1 char */
+#define utf8_strlen(S, B) ((B) < 0 ? (int)strlen(S) : (B))
+#define utf8_strwidth(S, B) utf8_strlen((S), (B))
+#define utf8_tounicode(S, CP) (*(CP) = (unsigned char)*(S), 1)
+#define utf8_getchars(CP, C) (*(CP) = (C), 1)
+#define utf8_upper(C) toupper(C)
+#define utf8_title(C) toupper(C)
+#define utf8_lower(C) tolower(C)
+#define utf8_index(C, I) (I)
+#define utf8_charlen(C) 1
+#define utf8_prev_len(S, L) 1
+#define utf8_width(C) 1
+
+#else
+#if !defined(JIM_BOOTSTRAP)
+
+#define utf8_getchars utf8_fromunicode
+
+/**
+ * Returns the length of the utf-8 sequence starting with 'c'.
+ *
+ * Returns 1-4.
+ * If 'c' is not a valid start byte, returns 1.
+ */
+int utf8_charlen(int c);
+
+/**
+ * Returns the number of characters in the utf-8
+ * string of the given byte length.
+ *
+ * Any bytes which are not part of an valid utf-8
+ * sequence are treated as individual characters.
+ *
+ * The string *must* be null terminated.
+ *
+ * Does not support unicode code points > \u1fffff
+ */
+int utf8_strlen(const char *str, int bytelen);
+
+/**
+ * Calculates the display width of the first 'charlen' characters in 'str'.
+ * See utf8_width()
+ */
+int utf8_strwidth(const char *str, int charlen);
+
+/**
+ * Returns the byte index of the given character in the utf-8 string.
+ *
+ * The string *must* be null terminated.
+ *
+ * This will return the byte length of a utf-8 string
+ * if given the char length.
+ */
+int utf8_index(const char *str, int charindex);
+
+/**
+ * Returns the unicode codepoint corresponding to the
+ * utf-8 sequence 'str'.
+ *
+ * Stores the result in *uc and returns the number of bytes
+ * consumed.
+ *
+ * If 'str' is null terminated, then an invalid utf-8 sequence
+ * at the end of the string will be returned as individual bytes.
+ *
+ * If it is not null terminated, the length *must* be checked first.
+ *
+ * Does not support unicode code points > \u1fffff
+ */
+int utf8_tounicode(const char *str, int *uc);
+
+/**
+ * Returns the number of bytes before 'str' that the previous
+ * utf-8 character sequence starts (which may be the middle of a sequence).
+ *
+ * Looks back at most 'len' bytes backwards, which must be > 0.
+ * If no start char is found, returns -len
+ */
+int utf8_prev_len(const char *str, int len);
+
+/**
+ * Returns the upper-case variant of the given unicode codepoint.
+ *
+ * Unicode code points > \uffff are returned unchanged.
+ */
+int utf8_upper(int uc);
+
+/**
+ * Returns the title-case variant of the given unicode codepoint.
+ *
+ * If none, returns utf8_upper().
+ *
+ * Unicode code points > \uffff are returned unchanged.
+ */
+int utf8_title(int uc);
+
+/**
+ * Returns the lower-case variant of the given unicode codepoint.
+ *
+ * NOTE: Use utf8_upper() in preference for case-insensitive matching.
+ *
+ * Unicode code points > \uffff are returned unchanged.
+ */
+int utf8_lower(int uc);
+
+/**
+ * Returns the width (in characters) of the given unicode codepoint.
+ * This is 1 for normal letters and 0 for combining characters and 2 for wide characters.
+ */
+int utf8_width(int ch);
+
+#endif /* JIM_BOOTSTRAP */
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif