diff options
| -rw-r--r-- | src/misc_gui.cpp | 11 | ||||
| -rw-r--r-- | src/string.h | 22 |
2 files changed, 24 insertions, 9 deletions
diff --git a/src/misc_gui.cpp b/src/misc_gui.cpp index b736de9c4..306289eab 100644 --- a/src/misc_gui.cpp +++ b/src/misc_gui.cpp @@ -805,11 +805,7 @@ static void DelChar(Textbuf *tb, bool backspace) uint width; size_t len; - if (backspace) { - do { - tb->caretpos--; - } while (IsUtf8Part(*(tb->buf + tb->caretpos))); - } + if (backspace) tb->caretpos -= Utf8PrevCharLen(tb->buf + tb->caretpos); len = Utf8Decode(&c, tb->buf + tb->caretpos); width = GetCharacterWidth(FS_NORMAL, c); @@ -892,10 +888,7 @@ bool MoveTextBufferPos(Textbuf *tb, int navmode) if (tb->caretpos != 0) { WChar c; - do { - tb->caretpos--; - } while (IsUtf8Part(*(tb->buf + tb->caretpos))); - + tb->caretpos -= Utf8PrevCharLen(tb->buf + tb->caretpos); Utf8Decode(&c, tb->buf + tb->caretpos); tb->caretxoffs -= GetCharacterWidth(FS_NORMAL, c); diff --git a/src/string.h b/src/string.h index 6b9924d63..da07f08d5 100644 --- a/src/string.h +++ b/src/string.h @@ -106,6 +106,28 @@ static inline bool IsUtf8Part(char c) return GB(c, 6, 2) == 2; } +/** + * Retrieve the (partial) length of the previous UNICODE character + * in an UTF-8 encoded string. + * @param s char pointer pointing to the first char of the next character + * @returns the decoded length in bytes (size) of the UNICODE character + * that was just before the one where 's' is pointing to + * @note If 's' is not pointing to the first byte of the next UNICODE character + * only a partial length of the sequence will be returned. + * For example given this sequence: 0xE3 0x85 0x80, 0xE3 0x81 0x9E + * 1. 's' is pointing to the second 0xE3, return value is 3 + * 2. 's' is pointing to 0x80, return value is 2. + * So take care with the return values of this function. To get the real length + * for an (invalid) sequence, pass the string offset of this function's return + * value to Utf8EncodedCharLen() or Utf8Decode() + */ +static inline size_t Utf8PrevCharLen(const char *s) +{ + size_t len = 1; + while (IsUtf8Part(*--s)) len++; + return len; +} + static inline bool IsPrintable(WChar c) { |