blob: 567086f09cd4f711255b9bea6143abda0e253d91
| 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" |
| 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(resize, BB_DIR_USR_BIN, BB_SUID_DROP)) |
| 27 | |
| 28 | //kbuild:lib-$(CONFIG_RESIZE) += resize.o |
| 29 | |
| 30 | //usage:#define resize_trivial_usage |
| 31 | //usage: "" |
| 32 | //usage:#define resize_full_usage "\n\n" |
| 33 | //usage: "Resize the screen" |
| 34 | |
| 35 | #include "libbb.h" |
| 36 | #include "common_bufsiz.h" |
| 37 | |
| 38 | #define ESC "\033" |
| 39 | |
| 40 | #define old_termios_p ((struct termios*)bb_common_bufsiz1) |
| 41 | #define INIT_G() do { setup_common_bufsiz(); } while (0) |
| 42 | |
| 43 | static void |
| 44 | onintr(int sig UNUSED_PARAM) |
| 45 | { |
| 46 | tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p); |
| 47 | _exit(EXIT_FAILURE); |
| 48 | } |
| 49 | |
| 50 | int resize_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| 51 | int resize_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM) |
| 52 | { |
| 53 | struct termios new; |
| 54 | struct winsize w = { 0, 0, 0, 0 }; |
| 55 | int ret; |
| 56 | |
| 57 | INIT_G(); |
| 58 | |
| 59 | /* We use _stderr_ in order to make resize usable |
| 60 | * in shell backticks (those redirect stdout away from tty). |
| 61 | * NB: other versions of resize open "/dev/tty" |
| 62 | * and operate on it - should we do the same? |
| 63 | */ |
| 64 | |
| 65 | tcgetattr(STDERR_FILENO, old_termios_p); /* fiddle echo */ |
| 66 | memcpy(&new, old_termios_p, sizeof(new)); |
| 67 | new.c_cflag |= (CLOCAL | CREAD); |
| 68 | new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); |
| 69 | bb_signals(0 |
| 70 | + (1 << SIGINT) |
| 71 | + (1 << SIGQUIT) |
| 72 | + (1 << SIGTERM) |
| 73 | + (1 << SIGALRM) |
| 74 | , onintr); |
| 75 | tcsetattr(STDERR_FILENO, TCSANOW, &new); |
| 76 | |
| 77 | /* save_cursor_pos 7 |
| 78 | * scroll_whole_screen [r |
| 79 | * put_cursor_waaaay_off [$x;$yH |
| 80 | * get_cursor_pos [6n |
| 81 | * restore_cursor_pos 8 |
| 82 | */ |
| 83 | fprintf(stderr, ESC"7" ESC"[r" ESC"[999;999H" ESC"[6n"); |
| 84 | alarm(3); /* Just in case terminal won't answer */ |
| 85 | //BUG: death by signal won't restore termios |
| 86 | scanf(ESC"[%hu;%huR", &w.ws_row, &w.ws_col); |
| 87 | fprintf(stderr, ESC"8"); |
| 88 | |
| 89 | /* BTW, other versions of resize recalculate w.ws_xpixel, ws.ws_ypixel |
| 90 | * by calculating character cell HxW from old values |
| 91 | * (gotten via TIOCGWINSZ) and recomputing *pixel values */ |
| 92 | ret = ioctl(STDERR_FILENO, TIOCSWINSZ, &w); |
| 93 | |
| 94 | tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p); |
| 95 | |
| 96 | if (ENABLE_FEATURE_RESIZE_PRINT) |
| 97 | printf("COLUMNS=%d;LINES=%d;export COLUMNS LINES;\n", |
| 98 | w.ws_col, w.ws_row); |
| 99 | |
| 100 | return ret; |
| 101 | } |
| 102 |