Fix author abbreviation to handle multi-byte and multi-column characters

diff --git a/tig.c b/tig.c
index 0d16f767be7d2375875d26c68b75060834364401..1c7928dabe56900a2f384c920c36169c3b2f17a1 100644 (file)
--- a/tig.c
+++ b/tig.c
@@ -70,6 +70,7 @@ static void warn(const char *msg, ...);
 static void report(const char *msg, ...);
 static void set_nonblocking_input(bool loading);
 static size_t utf8_length(const char **string, size_t col, int *width, size_t max_width, int *trimmed, bool reserve);
+static inline unsigned char utf8_char_length(const char *string, const char *end);
 
 #define ABS(x)         ((x) >= 0  ? (x) : -(x))
 #define MIN(x, y)      ((x) < (y) ? (x) :  (y))
@@ -461,22 +462,36 @@ static const struct enum_map author_map[] = {
 #undef AUTHOR_
 };
 
-/* FIXME: Handle multi-byte and multi-column characters. */
 static const char *
-get_author_initials(const char *author, size_t max_columns)
+get_author_initials(const char *author)
 {
-       static char initials[AUTHOR_COLS];
-       size_t pos;
+       static char initials[AUTHOR_COLS * 6 + 1];
+       size_t pos = 0;
+       const char *end = strchr(author, '\0');
 
 #define is_initial_sep(c) (isspace(c) || ispunct(c) || (c) == '@' || (c) == '-')
 
        memset(initials, 0, sizeof(initials));
-       for (pos = 0; *author && pos < sizeof(initials) - 1; author++, pos++) {
+       while (author < end) {
+               unsigned char bytes;
+               size_t i;
+
                while (is_initial_sep(*author))
                        author++;
-               strncpy(&initials[pos], author, sizeof(initials) - 1 - pos);
-               while (*author && author[1] && !is_initial_sep(author[1]))
-                       author++;
+
+               bytes = utf8_char_length(author, end);
+               if (bytes < sizeof(initials) - 1 - pos) {
+                       while (bytes--) {
+                               initials[pos++] = *author++;
+                       }
+               }
+
+               for (i = pos; author < end && !is_initial_sep(*author); author++) {
+                       if (i < sizeof(initials) - 1)
+                               initials[i++] = *author;
+               }
+
+               initials[i++] = 0;
        }
 
        return initials;
@@ -2259,7 +2274,7 @@ draw_author(struct view *view, const char *author)
        bool abbreviate = opt_author == AUTHOR_ABBREVIATED || !trim;
 
        if (abbreviate && author)
-               author = get_author_initials(author, opt_author_cols);
+               author = get_author_initials(author);
 
        return draw_field(view, LINE_AUTHOR, author, opt_author_cols, trim);
 }
@@ -6795,6 +6810,14 @@ static const unsigned char utf8_bytes[256] = {
        3,3,3,3,3,3,3,3, 3,3,3,3,3,3,3,3, 4,4,4,4,4,4,4,4, 5,5,5,5,6,6,1,1,
 };
 
+static inline unsigned char
+utf8_char_length(const char *string, const char *end)
+{
+       int c = *(unsigned char *) string;
+
+       return utf8_bytes[c];
+}
+
 /* Decode UTF-8 multi-byte representation into a Unicode character. */
 static inline unsigned long
 utf8_to_unicode(const char *string, size_t length)
@@ -6862,8 +6885,7 @@ utf8_length(const char **start, size_t skip, int *width, size_t max_width, int *
        *trimmed = 0;
 
        while (string < end) {
-               int c = *(unsigned char *) string;
-               unsigned char bytes = utf8_bytes[c];
+               unsigned char bytes = utf8_char_length(string, end);
                size_t ucwidth;
                unsigned long unicode;