Re: utf8 hack for ls

[Ted Unangst]

Ted Unangst wrote:
> Christian Weisgerber wrote:
> > On 2015-10-23, "Ted Unangst" <t...@tedunangst.com> wrote:
> > 
> > >> To what degree should tools like ls protect terminals from escape codes?
> > >
> > > I think this is beyond the scope of what ls should care about. du doesn't 
> > > have
> > > such a check. Does the shell perform a check before tab completing?
> > 
> > Our ksh, bash, and tcsh all escape unprintable characters.
> 
> well, if this is a blocking issue, the putchar line is now changed to print ?
> instead of any control characters.
> 
>       putchar(c >= ' ' ? c : '?');

The very latest and greatest. Not much changed. We could use a u8width()
function analog of wcswidth, but len seems to do alright for the simple cases.

Index: ls.c
===================================================================
RCS file: /cvs/src/bin/ls/ls.c,v
retrieving revision 1.43
diff -u -p -r1.43 ls.c
--- ls.c        9 Oct 2015 01:37:06 -0000       1.43
+++ ls.c        23 Oct 2015 12:39:52 -0000
@@ -410,6 +410,8 @@ traverse(int argc, char *argv[], int opt
        fts_close(ftsp);
 }
 
+extern size_t u8len(char *);
+
 /*
  * Display() takes a linked list of FTSENT structures and passes the list
  * along with any other necessary information to the print function.  P
@@ -474,8 +476,8 @@ display(FTSENT *p, FTSENT *list)
                                continue;
                        }
                }
-               if (cur->fts_namelen > maxlen)
-                       maxlen = cur->fts_namelen;
+               if (u8len(cur->fts_name) > maxlen)
+                       maxlen = u8len(cur->fts_name);
                if (needstats) {
                        sp = cur->fts_statp;
                        if (sp->st_blocks > maxblock)
Index: util.c
===================================================================
RCS file: /cvs/src/bin/ls/util.c,v
retrieving revision 1.16
diff -u -p -r1.16 util.c
--- util.c      21 Nov 2013 15:54:45 -0000      1.16
+++ util.c      24 Oct 2015 11:49:56 -0000
@@ -46,12 +46,34 @@
 #include "extern.h"
 
 int
+isu8cont(unsigned char c)
+{
+       return ((c & (0x80 | 0x40)) == 0x80);
+}
+size_t
+u8len(const char *s)
+{
+       size_t len = 0;
+
+       for (; *s; s++)
+               if (!isu8cont(*s))
+                       len++;
+       return len;
+}
+
+int
 putname(char *name)
 {
        int len;
 
-       for (len = 0; *name; len++, name++)
-               putchar((!isprint((unsigned char)*name) && f_nonprint) ? '?' : 
*name);
+       for (len = 0; *name; name++) {
+               unsigned char c = *name;
+               if (!isu8cont(c))
+                       len++;
+               if (isascii(c) && !isprint(c))
+                       c = '?';
+               putchar(c);
+       }
        return len;
 }