1 files changed, 90 insertions, 0 deletions
diff --git a/utf8.h b/utf8.h
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index 0000000..9e03059
--- /dev/null
+++ b/utf8.h
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+#ifndef UTF8_UTIL_H
+#define UTF8_UTIL_H
+
+/**
+ * Converts the given unicode codepoint (0 - 0xffff) to utf-8
+ * and stores the result at 'p'.
+ * 
+ * Returns the number of utf-8 characters (1-3).
+ */
+int utf8_fromunicode(char *p, unsigned short uc);
+
+#ifndef JIM_UTF8
+#include <ctype.h>
+
+/* No utf-8 support. 1 byte = 1 char */
+#define utf8_strlen(S, B) (B) < 0 ? strlen(S) : (B)
+#define utf8_tounicode(S, CP) (*(CP) = *(S), 1)
+#define utf8_upper(C) toupper(C)
+#define utf8_lower(C) tolower(C)
+#define utf8_index(C, I) (I)
+#define utf8_charlen(C) 1
+
+#else
+/**
+ * Returns the length of the utf-8 sequence starting with 'c'.
+ * 
+ * Returns 1-4, or -1 if this is not a valid start byte.
+ *
+ * Note that charlen=4 is not supported by the rest of the API.
+ */
+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 > \uffff
+ */
+int utf8_strlen(const char *str, int bytelen);
+
+/**
+ * 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 > \uffff
+ */
+int utf8_tounicode(const char *str, int *uc);
+
+/**
+ * Returns the upper-case variant of the given unicode codepoint.
+ *
+ * Does not support unicode code points > \uffff
+ */
+int utf8_upper(int uc);
+
+/**
+ * Returns the lower-case variant of the given unicode codepoint.
+ *
+ * NOTE: Use utf8_upper() in preference for case-insensitive matching.
+ *
+ * Does not support unicode code points > \uffff
+ */
+int utf8_lower(int uc);
+
+#endif
+
+#endif