1/* vi: set sw=4 ts=4: */ 2/* 3 * resize - set terminal width and height. 4 * 5 * Copyright 2006 Bernhard Reutner-Fischer 6 * 7 * Licensed under GPLv2 or later, see file LICENSE in this source tree. 8 */ 9//config:config RESIZE 10//config: bool "resize (903 bytes)" 11//config: default y 12//config: help 13//config: This program is used to (re)set the width and height of your current 14//config: terminal. 15//config: 16//config:config FEATURE_RESIZE_PRINT 17//config: bool "Print environment variables" 18//config: default y 19//config: depends on RESIZE 20//config: help 21//config: Prints the newly set size (number of columns and rows) of 22//config: the terminal. 23//config: E.g.: 24//config: COLUMNS=80;LINES=44;export COLUMNS LINES; 25 26//applet:IF_RESIZE(APPLET_NOEXEC(resize, resize, BB_DIR_USR_BIN, BB_SUID_DROP, resize)) 27/* bb_common_bufsiz1 usage here is safe wrt NOEXEC: not expecting it to be zeroed. */ 28 29//kbuild:lib-$(CONFIG_RESIZE) += resize.o 30 31//usage:#define resize_trivial_usage 32//usage: "" 33//usage:#define resize_full_usage "\n\n" 34//usage: "Resize the screen" 35 36#include "libbb.h" 37#include "common_bufsiz.h" 38 39#define ESC "\033" 40 41#define old_termios_p ((struct termios*)bb_common_bufsiz1) 42#define INIT_G() do { setup_common_bufsiz(); } while (0) 43 44static void 45onintr(int sig UNUSED_PARAM) 46{ 47 tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p); 48 _exit(EXIT_FAILURE); 49} 50 51int resize_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; 52int resize_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM) 53{ 54 struct termios new; 55 struct winsize w = { 0, 0, 0, 0 }; 56 int ret; 57 58 INIT_G(); 59 60 /* We use _stderr_ in order to make resize usable 61 * in shell backticks (those redirect stdout away from tty). 62 * NB: other versions of resize open "/dev/tty" 63 * and operate on it - should we do the same? 64 */ 65 66 tcgetattr(STDERR_FILENO, old_termios_p); /* fiddle echo */ 67//TODO: die if the above fails? 68 memcpy(&new, old_termios_p, sizeof(new)); 69 new.c_cflag |= (CLOCAL | CREAD); 70 new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); 71 bb_signals(0 72 + (1 << SIGINT) 73 + (1 << SIGQUIT) 74 + (1 << SIGTERM) 75 + (1 << SIGALRM) 76 , onintr); 77 tcsetattr(STDERR_FILENO, TCSANOW, &new); 78 79 /* save_cursor_pos 7 80 * scroll_whole_screen [r 81 * put_cursor_waaaay_off [$x;$yH 82 * get_cursor_pos [6n 83 * restore_cursor_pos 8 84 */ 85 fprintf(stderr, ESC"7" ESC"[r" ESC"[999;999H" ESC"[6n"); 86 alarm(3); /* Just in case terminal won't answer */ 87//BUG: death by signal won't restore termios 88 scanf(ESC"[%hu;%huR", &w.ws_row, &w.ws_col); 89 fprintf(stderr, ESC"8"); 90 91 /* BTW, other versions of resize recalculate w.ws_xpixel, ws.ws_ypixel 92 * by calculating character cell HxW from old values 93 * (gotten via TIOCGWINSZ) and recomputing *pixel values */ 94 ret = ioctl(STDERR_FILENO, TIOCSWINSZ, &w); 95 96 tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p); 97 98 if (ENABLE_FEATURE_RESIZE_PRINT) 99 printf("COLUMNS=%d;LINES=%d;export COLUMNS LINES;\n", 100 w.ws_col, w.ws_row); 101 102 return ret; 103} 104