blob: 4b0d63a03c8086a802e8d889aeeeb38b549f601f
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 | /* no options, no getopt */ |
10 | |
11 | //usage:#define resize_trivial_usage |
12 | //usage: "" |
13 | //usage:#define resize_full_usage "\n\n" |
14 | //usage: "Resize the screen" |
15 | |
16 | #include "libbb.h" |
17 | |
18 | #define ESC "\033" |
19 | |
20 | #define old_termios_p ((struct termios*)&bb_common_bufsiz1) |
21 | |
22 | static void |
23 | onintr(int sig UNUSED_PARAM) |
24 | { |
25 | tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p); |
26 | _exit(EXIT_FAILURE); |
27 | } |
28 | |
29 | int resize_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
30 | int resize_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM) |
31 | { |
32 | struct termios new; |
33 | struct winsize w = { 0, 0, 0, 0 }; |
34 | int ret; |
35 | |
36 | /* We use _stderr_ in order to make resize usable |
37 | * in shell backticks (those redirect stdout away from tty). |
38 | * NB: other versions of resize open "/dev/tty" |
39 | * and operate on it - should we do the same? |
40 | */ |
41 | |
42 | tcgetattr(STDERR_FILENO, old_termios_p); /* fiddle echo */ |
43 | memcpy(&new, old_termios_p, sizeof(new)); |
44 | new.c_cflag |= (CLOCAL | CREAD); |
45 | new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); |
46 | bb_signals(0 |
47 | + (1 << SIGINT) |
48 | + (1 << SIGQUIT) |
49 | + (1 << SIGTERM) |
50 | + (1 << SIGALRM) |
51 | , onintr); |
52 | tcsetattr(STDERR_FILENO, TCSANOW, &new); |
53 | |
54 | /* save_cursor_pos 7 |
55 | * scroll_whole_screen [r |
56 | * put_cursor_waaaay_off [$x;$yH |
57 | * get_cursor_pos [6n |
58 | * restore_cursor_pos 8 |
59 | */ |
60 | fprintf(stderr, ESC"7" ESC"[r" ESC"[999;999H" ESC"[6n"); |
61 | alarm(3); /* Just in case terminal won't answer */ |
62 | //BUG: death by signal won't restore termios |
63 | scanf(ESC"[%hu;%huR", &w.ws_row, &w.ws_col); |
64 | fprintf(stderr, ESC"8"); |
65 | |
66 | /* BTW, other versions of resize recalculate w.ws_xpixel, ws.ws_ypixel |
67 | * by calculating character cell HxW from old values |
68 | * (gotten via TIOCGWINSZ) and recomputing *pixel values */ |
69 | ret = ioctl(STDERR_FILENO, TIOCSWINSZ, &w); |
70 | |
71 | tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p); |
72 | |
73 | if (ENABLE_FEATURE_RESIZE_PRINT) |
74 | printf("COLUMNS=%d;LINES=%d;export COLUMNS LINES;\n", |
75 | w.ws_col, w.ws_row); |
76 | |
77 | return ret; |
78 | } |
79 |