top(1): support multibyte characters in command names (ARGV array)

depending on locale.

 - add setlocale()
 - remove printable() function
 - add VIS_OCTAL and VIS_SAFE to the flag of strvisx() to display
   non-printable characters that do not use C-style backslash sequences
   in three digit octal sequence, or remove it

This change allows multibyte characters to be displayed according to
locale. If it is recognized as a non-display character according to the
locale, it is displayed in three digit octal sequence.

Reference:
https://www.mail-archive.com/svn-src-all@freebsd.org/msg165751.html
https://www.mail-archive.com/svn-src-all@freebsd.org/msg165766.html
https://www.mail-archive.com/svn-src-all@freebsd.org/msg165833.html
https://www.mail-archive.com/svn-src-all@freebsd.org/msg165846.html
https://www.mail-archive.com/svn-src-all@freebsd.org/msg165891.html

Submitted by: hrs
Differential Revision: https://reviews.freebsd.org/D16204

5 files changed, 13 insertions, 29 deletions

diff --git a/usr.bin/top/display.c b/usr.bin/top/display.c
index 00534fd7f411..38e6657401d0 100644
--- a/usr.bin/top/display.c
+++ b/usr.bin/top/display.c
@@ -1291,31 +1291,6 @@ line_update(char *old, char *new, int start, int line)
     }
 }
 
-/*
- *  printable(str) - make the string pointed to by "str" into one that is
- *	printable (i.e.: all ascii), by converting all non-printable
- *	characters into '?'.  Replacements are done in place and a pointer
- *	to the original buffer is returned.
- */
-
-char *
-printable(char str[])
-{
-    char *ptr;
-    char ch;
-
-    ptr = str;
-    while ((ch = *ptr) != '\0')
-    {
-	if (!isprint(ch))
-	{
-	    *ptr = '?';
-	}
-	ptr++;
-    }
-    return(str);
-}
-
 void
 i_uptime(struct timeval *bt, time_t *tod)
 {
diff --git a/usr.bin/top/display.h b/usr.bin/top/display.h
index 546f21ce34b0..ff3ea8d3fe9a 100644
--- a/usr.bin/top/display.h
+++ b/usr.bin/top/display.h
@@ -11,7 +11,6 @@ int		 display_updatecpus(struct statics *statics);
 void	 clear_message(void);
 int		 display_resize(void);
 void	 i_header(const char *text);
-char	*printable(char *string);
 void	 display_header(int t);
 int		 display_init(struct statics *statics);
 void	 i_arc(int *stats);
diff --git a/usr.bin/top/machine.c b/usr.bin/top/machine.c
index dd2b7a110419..edfe3e659f13 100644
--- a/usr.bin/top/machine.c
+++ b/usr.bin/top/machine.c
@@ -1003,7 +1003,7 @@ format_next_process(struct handle * xhandle, char *(*get_userid)(int), int flags
 				len = (argbuflen - (dst - argbuf) - 1) / 4;
 				strvisx(dst, src,
 				    MIN(strlen(src), len),
-				    VIS_NL | VIS_CSTYLE);
+				    VIS_NL | VIS_CSTYLE | VIS_OCTAL | VIS_SAFE);
 				while (*dst != '\0')
 					dst++;
 				if ((argbuflen - (dst - argbuf) - 1) / 4 > 0)
@@ -1102,7 +1102,7 @@ format_next_process(struct handle * xhandle, char *(*get_userid)(int), int flags
 		sbuf_printf(procbuf, "%6s ", format_time(cputime));
 		sbuf_printf(procbuf, "%6.2f%% ", ps.wcpu ? 100.0 * weighted_cpu(PCTCPU(pp), pp) : 100.0 * PCTCPU(pp));
 	}
-	sbuf_printf(procbuf, "%s", printable(cmdbuf));
+	sbuf_printf(procbuf, "%s", cmdbuf);
 	free(cmdbuf);
 	return (sbuf_data(procbuf));
 }
diff --git a/usr.bin/top/top.1 b/usr.bin/top/top.1
index a2858003d465..83c2c3440893 100644
--- a/usr.bin/top/top.1
+++ b/usr.bin/top/top.1
@@ -1,5 +1,5 @@
 .\" $FreeBSD$
-.Dd October 2, 2018
+.Dd September 20, 2019
 .Dt TOP 1
 .Os
 .Sh NAME
@@ -192,6 +192,10 @@ or
 \*(lqall\*(rq.
 Boolean flags are toggles.
 A second specification of any of these options will negate the first.
+.Pp
+The display of command names changes according to the locale.
+If command names displayed in the locale settings are recognized as 
+non-display characters, they are displayed in three digit octal sequence.
 .Sh "INTERACTIVE MODE"
 When
 .Nm
diff --git a/usr.bin/top/top.c b/usr.bin/top/top.c
index 650789689b6b..01cad421b64c 100644
--- a/usr.bin/top/top.c
+++ b/usr.bin/top/top.c
@@ -25,6 +25,7 @@
 #include <errno.h>
 #include <getopt.h>
 #include <jail.h>
+#include <locale.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -265,6 +266,11 @@ main(int argc, const char *argv[])
     setbuffer(stdout, stdoutbuf, Buffersize);
 #endif
 
+    if (setlocale(LC_ALL, "") == NULL) {
+        fprintf(stderr, "invalid locale.\n");
+	exit(1);
+    }
+
     mypid = getpid();
 
     /* get our name */