lineedit: fix unicode characters in prompt

function                                             old     new   delta
parse_and_put_prompt                                 779     823     +44

Signed-off-by: Audun-Marius Gangstø <audun@gangsto.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index e40a72064..a3b798e3f 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -2029,10 +2029,17 @@ static void parse_and_put_prompt(const char *prmt_ptr)
                         if (c == '\n')
                                 cmdedit_prmt_len = 0;
                         else if (flg_not_length != ']') {
-#if 0 /*ENABLE_UNICODE_SUPPORT*/
-/* Won't work, pbuf is one BYTE string here instead of an one Unicode char string. */
-/* FIXME */
-                                cmdedit_prmt_len += unicode_strwidth(pbuf);
+#if ENABLE_UNICODE_SUPPORT
+                                if (n == 1) {
+                                        /* Only count single-byte characters and the first of multi-byte characters */
+                                        if ((unsigned char)*pbuf < 0x80  /* single byte character */
+                                         || (unsigned char)*pbuf >= 0xc0 /* first of multi-byte characters */
+                                        ) {
+                                                cmdedit_prmt_len += n;
+                                        }
+                                } else {
+                                        cmdedit_prmt_len += unicode_strwidth(pbuf);
+                                }
 #else
                                 cmdedit_prmt_len += n;
 #endif