[PATCH] client: handle wide chars for table rows

[Pinghao Wu <xdavidwuph@gmail.com>]

Try to find out printing width of wide chars using current locale and
its byte length before falling back to non-codepoint UTF-8 bytes method.
---
 client/display.c | 16 +++++++++++++++-
 client/main.c    |  3 +++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/client/display.c b/client/display.c
index b729ad4c..dcbe11f8 100644
--- a/client/display.c
+++ b/client/display.c
@@ -26,10 +26,13 @@
 
 #define _GNU_SOURCE
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <signal.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
 #include <unistd.h>
+#include <wchar.h>
 
 #include <readline/history.h>
 #include <readline/readline.h>
@@ -401,15 +404,26 @@ static char* next_line(char *s, unsigned int *max, char **color_out)
 	unsigned int i;
 	int last_space = -1;
 	int last_color = -1;
+	int s_len = strlen(s);
 
 	/* Find the last space before 'max', as well as any color */
-	for (i = 0; i <= *max && s[i] != '\0'; i++) {
+	for (i = 0; i <= *max && i != s_len; i++) {
 		if (s[i] == ' ')
 			last_space = i;
 		else if (s[i] == 0x1b) {
 			/* color escape won't count for column width */
 			*max += color_end(s + i);
 			last_color = i;
+		/* Non-ASCII, try wchar */
+		} else if (s[i] & 0x80) {
+			wchar_t w;
+			int w_mblen;
+			if ((w_mblen = mbtowc(&w, &s[i], s_len - i)) > 0) {
+				/* Compensate max bytes for wide char */
+				*max += w_mblen - wcwidth(w);
+				/* Skip other bytes for this wchar */
+				i += w_mblen - 1;
+			}
 		/* Add width for non-codepoint UTF-8 bytes */
 		} else if (((uint8_t)s[i] >> 6) == 2)
 			*max += 1;
diff --git a/client/main.c b/client/main.c
index df5c0a61..7e8dead4 100644
--- a/client/main.c
+++ b/client/main.c
@@ -25,6 +25,7 @@
 #endif
 
 #include <errno.h>
+#include <locale.h>
 #include <signal.h>
 #include <ell/ell.h>
 
@@ -50,6 +51,8 @@ int main(int argc, char *argv[])
 {
 	bool all_done;
 
+	setlocale(LC_CTYPE, "");
+
 	if (!l_main_init())
 		return EXIT_FAILURE;
 
-- 
2.38.0