1/* vi: set sw=4 ts=4: */ 2/* 3 * resize - set terminal width and height. 4 * 5 * Copyright 2006 Bernhard Fischer 6 * 7 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. 8 */ 9/* no options, no getopt */ 10#include "libbb.h" 11 12#define ESC "\033" 13 14#define old_termios (*(struct termios*)&bb_common_bufsiz1) 15 16static void 17onintr(int sig ATTRIBUTE_UNUSED) 18{ 19 tcsetattr(STDERR_FILENO, TCSANOW, &old_termios); 20 exit(1); 21} 22 23int resize_main(int argc, char **argv); 24int resize_main(int argc, char **argv) 25{ 26 struct termios new; 27 struct winsize w = { 0,0,0,0 }; 28 int ret; 29 30 /* We use _stderr_ in order to make resize usable 31 * in shell backticks (those redirect stdout away from tty). 32 * NB: other versions of resize open "/dev/tty" 33 * and operate on it - should we do the same? 34 */ 35 36 tcgetattr(STDERR_FILENO, &old_termios); /* fiddle echo */ 37 new = old_termios; 38 new.c_cflag |= (CLOCAL | CREAD); 39 new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); 40 signal(SIGINT, onintr); 41 signal(SIGQUIT, onintr); 42 signal(SIGTERM, onintr); 43 signal(SIGALRM, onintr); 44 tcsetattr(STDERR_FILENO, TCSANOW, &new); 45 46 /* save_cursor_pos 7 47 * scroll_whole_screen [r 48 * put_cursor_waaaay_off [$x;$yH 49 * get_cursor_pos [6n 50 * restore_cursor_pos 8 51 */ 52 fprintf(stderr, ESC"7" ESC"[r" ESC"[999;999H" ESC"[6n"); 53 alarm(3); /* Just in case terminal won't answer */ 54 scanf(ESC"[%hu;%huR", &w.ws_row, &w.ws_col); 55 fprintf(stderr, ESC"8"); 56 57 /* BTW, other versions of resize recalculate w.ws_xpixel, ws.ws_ypixel 58 * by calculating character cell HxW from old values 59 * (gotten via TIOCGWINSZ) and recomputing *pixel values */ 60 ret = ioctl(STDERR_FILENO, TIOCSWINSZ, &w); 61 62 tcsetattr(STDERR_FILENO, TCSANOW, &old_termios); 63 64 if (ENABLE_FEATURE_RESIZE_PRINT) 65 printf("COLUMNS=%d;LINES=%d;export COLUMNS LINES;\n", 66 w.ws_col, w.ws_row); 67 68 return ret; 69} 70