free: Use wstr width and not length

The previous commit used the value from mbstowcs() to work out
the spacing required, as printf() got it completely wrong.

However, for alignment of text you don't use the string length
but the string width.

As the referenced website says:
 Use wcslen when allocating memory for wide characters, and use wcswidth to
 align text.

Which is what free does now. Chinese is still off by one but I cannot
see why this is so. It's close enough for now. If someone can work
it out, I'd love to know what the fix is.

As a side effect, #213 is fixed because we are putting the correct
number of spaces in.

French is still an issue (see #24 ) but this is because the string is
too long!

References:
 procps-ng/procps#24
 procps-ng/procps#213
 procps-ng/procps#229
 commit 9f4db0fb5606e4872829bd44b29443d5707b1505
 https://www.linux.com/news/programming-wide-characters/

Signed-off-by: Craig Small <csmall@dropbear.xyz>

diff --git a/NEWS b/NEWS
index d8417d3cd060ef64e6ab58df21ab2141a4e70ccc..a487278ae1375cd4becae5ff29e9c2bf0b6a65a7 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,7 @@ procps-ng-NEXT
   * free: Add committed line option                        merge #25
   * free: Fix -h --si combined options                     issue #133, #223
   * free: Fix first column justification                   issue #229, #204, #206, Debian #1001689
+  * free: Better spacing for Chinese language              issue #213
   * library: renamed to libproc-2 and reset to 0:0:0
   * library: add support for accessing smaps_rollup        issue #112, #201
   * library: add support for accessing autogroups

diff --git a/free.c b/free.c
index 4e989af4e8c622503d55957a5b844637780d2f5b..94943e8884ecf61f15d1d2d11c4d72f075073db7 100644 (file)
--- a/free.c
+++ b/free.c
@@ -34,6 +34,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <wchar.h>
 
 #include "config.h"
 #include "c.h"
@@ -185,13 +186,18 @@ static void print_head_col(const char *str)
 {
     int len;
     int spaces = 9;
+    wchar_t wstr[BUFSIZ];
 
-    len = mbstowcs(NULL, str, 0);
+    len = mbstowcs(wstr, str, BUFSIZ);
     if (len < 0)
         spaces = 9;
-    else if (len < HC_WIDTH)
-        spaces = HC_WIDTH - len;
-    else
+    else if (len < HC_WIDTH) {
+        int width;
+        if ( (width = wcswidth(wstr, 99)) > 0)
+            spaces = HC_WIDTH - width;
+        else
+            spaces = HC_WIDTH - len;
+    } else
         spaces = 0;
 
     printf("%s%.*s", str, spaces, "         ");