busybox/console-tools/resize.c
Denis Vlasenko 25591c322c libbb: introduce bb_signals and bb_signals_recursive,
which sets same handler for many signals. sig_catch is nuked
(bb_signals_recursive is more descriptive name).
*: use them as appropriate. 

function                                             old     new   delta
bb_signals_recursive                                   -      95     +95
bb_signals                                             -      52     +52
run_command                                          258     273     +15
svlogd_main                                         1368    1377      +9
runsv_main                                          1746    1752      +6
runsvdir_main                                       1643    1646      +3
UNSPEC_print                                          64      66      +2
time_main                                           1128    1127      -1
...
resize_main                                          246     210     -36
sig_catch                                             63       -     -63
set_fatal_sighandler                                  85      14     -71
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 5/24 up/down: 182/-548)        Total: -366 bytes
2008-02-16 22:58:56 +00:00

72 lines
1.8 KiB
C

/* vi: set sw=4 ts=4: */
/*
* resize - set terminal width and height.
*
* Copyright 2006 Bernhard Fischer
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* no options, no getopt */
#include "libbb.h"
#define ESC "\033"
#define old_termios (*(struct termios*)&bb_common_bufsiz1)
static void
onintr(int sig ATTRIBUTE_UNUSED)
{
tcsetattr(STDERR_FILENO, TCSANOW, &old_termios);
exit(1);
}
int resize_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int resize_main(int argc, char **argv)
{
struct termios new;
struct winsize w = { 0,0,0,0 };
int ret;
/* We use _stderr_ in order to make resize usable
* in shell backticks (those redirect stdout away from tty).
* NB: other versions of resize open "/dev/tty"
* and operate on it - should we do the same?
*/
tcgetattr(STDERR_FILENO, &old_termios); /* fiddle echo */
new = old_termios;
new.c_cflag |= (CLOCAL | CREAD);
new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
bb_signals(0
+ (1 << SIGINT)
+ (1 << SIGQUIT)
+ (1 << SIGTERM)
+ (1 << SIGALRM)
, onintr);
tcsetattr(STDERR_FILENO, TCSANOW, &new);
/* save_cursor_pos 7
* scroll_whole_screen [r
* put_cursor_waaaay_off [$x;$yH
* get_cursor_pos [6n
* restore_cursor_pos 8
*/
fprintf(stderr, ESC"7" ESC"[r" ESC"[999;999H" ESC"[6n");
alarm(3); /* Just in case terminal won't answer */
scanf(ESC"[%hu;%huR", &w.ws_row, &w.ws_col);
fprintf(stderr, ESC"8");
/* BTW, other versions of resize recalculate w.ws_xpixel, ws.ws_ypixel
* by calculating character cell HxW from old values
* (gotten via TIOCGWINSZ) and recomputing *pixel values */
ret = ioctl(STDERR_FILENO, TIOCSWINSZ, &w);
tcsetattr(STDERR_FILENO, TCSANOW, &old_termios);
if (ENABLE_FEATURE_RESIZE_PRINT)
printf("COLUMNS=%d;LINES=%d;export COLUMNS LINES;\n",
w.ws_col, w.ws_row);
return ret;
}