74 lines
3.5 KiB
C
74 lines
3.5 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Copyright 2020 Justine Alexandra Roberts Tunney │
|
|
│ │
|
|
│ This program is free software; you can redistribute it and/or modify │
|
|
│ it under the terms of the GNU General Public License as published by │
|
|
│ the Free Software Foundation; version 2 of the License. │
|
|
│ │
|
|
│ This program is distributed in the hope that it will be useful, but │
|
|
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
|
|
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
|
|
│ General Public License for more details. │
|
|
│ │
|
|
│ You should have received a copy of the GNU General Public License │
|
|
│ along with this program; if not, write to the Free Software │
|
|
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
|
|
│ 02110-1301 USA │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/bits/weaken.h"
|
|
#include "libc/calls/internal.h"
|
|
#include "libc/dce.h"
|
|
#include "libc/log/log.h"
|
|
#include "libc/nt/console.h"
|
|
#include "libc/nt/enum/consolemodeflags.h"
|
|
#include "libc/nt/enum/filetype.h"
|
|
#include "libc/nt/enum/version.h"
|
|
#include "libc/nt/files.h"
|
|
#include "libc/nt/pedef.internal.h"
|
|
#include "libc/nt/runtime.h"
|
|
#include "libc/nt/struct/teb.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#include "libc/str/str.h"
|
|
#include "libc/sysv/consts/fileno.h"
|
|
|
|
/**
|
|
* Returns true if ANSI terminal colors are appropriate.
|
|
*
|
|
* We take an optimistic approach here. We use colors, unless we see the
|
|
* environment variable TERM=dumb, which is set by software like Emacs.
|
|
* It's a common antipattern to check isatty(STDERR_FILENO), since that
|
|
* usually makes colors harder to get than they are to remove:
|
|
*
|
|
* sed 's/\x1b\[[;[:digit:]]*m//g' <color.txt >uncolor.txt
|
|
*
|
|
* Ideally, all software should be updated to understand color, since
|
|
* it's been formally standardized nearly as long as ASCII. Even old
|
|
* MS-DOS supports it (but Windows didn't until Windows 10) yet even
|
|
* tools like less may need wrapper scripts, e.g.:
|
|
*
|
|
* #!/bin/sh
|
|
* LESSCHARSET=UTF-8 exec /usr/bin/less -RS "$@"
|
|
*
|
|
* It's that easy fam.
|
|
*/
|
|
bool cancolor(void) {
|
|
static bool once;
|
|
static bool result;
|
|
const char *term;
|
|
if (!once) {
|
|
if (!result) {
|
|
if ((term = getenv("TERM"))) {
|
|
/* anything but emacs basically */
|
|
result = strcmp(term, "dumb") != 0;
|
|
} else {
|
|
/* TODO(jart): Why does Mac bash login shell exec nuke TERM? */
|
|
result = IsXnu();
|
|
}
|
|
}
|
|
once = true;
|
|
}
|
|
return result;
|
|
}
|