From c175c4664734e5a363d8cc8668c08f551eff1485 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 18 Apr 2010 22:09:30 -0700 Subject: vi: discover window size even on serial consoles. optional function old new delta edit_file 671 761 +90 wh_helper - 57 +57 query_screen_dimensions 54 63 +9 ar_main 533 542 +9 refresh 767 773 +6 vi_main 242 243 +1 text_yank 56 54 -2 get_terminal_width_height 180 135 -45 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 5/2 up/down: 172/-47) Total: 125 bytes Signed-off-by: Denys Vlasenko --- libbb/xfuncs.c | 54 ++++++++++++++++++++++++++++++------------------------ 1 file changed, 30 insertions(+), 24 deletions(-) (limited to 'libbb/xfuncs.c') diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c index aec165f06..d93dd2af9 100644 --- a/libbb/xfuncs.c +++ b/libbb/xfuncs.c @@ -210,34 +210,40 @@ char* FAST_FUNC xmalloc_ttyname(int fd) return buf; } -/* It is perfectly ok to pass in a NULL for either width or for - * height, in which case that value will not be set. */ -int FAST_FUNC get_terminal_width_height(int fd, unsigned *width, unsigned *height) +static int wh_helper(int value, int def_val, const char *env_name, int *err) { - struct winsize win = { 0, 0, 0, 0 }; - int ret = ioctl(fd, TIOCGWINSZ, &win); - - if (height) { - if (!win.ws_row) { - char *s = getenv("LINES"); - if (s) win.ws_row = atoi(s); - } - if (win.ws_row <= 1 || win.ws_row >= 30000) - win.ws_row = 24; - *height = (int) win.ws_row; - } - - if (width) { - if (!win.ws_col) { - char *s = getenv("COLUMNS"); - if (s) win.ws_col = atoi(s); + if (value == 0) { + char *s = getenv(env_name); + if (s) { + value = atoi(s); + /* If LINES/COLUMNS are set, pretent that there is + * no error getting w/h, this prevents some ugly + * cursor tricks by our callers */ + *err = 0; } - if (win.ws_col <= 1 || win.ws_col >= 30000) - win.ws_col = 80; - *width = (int) win.ws_col; } + if (value <= 1 || value >= 30000) + value = def_val; + return value; +} - return ret; +/* It is perfectly ok to pass in a NULL for either width or for + * height, in which case that value will not be set. */ +int FAST_FUNC get_terminal_width_height(int fd, unsigned *width, unsigned *height) +{ + struct winsize win; + int err; + + win.ws_row = 0; + win.ws_col = 0; + /* I've seen ioctl returning 0, but row/col is (still?) 0. + * We treat that as an error too. */ + err = ioctl(fd, TIOCGWINSZ, &win) != 0 || win.ws_row == 0; + if (height) + *height = wh_helper(win.ws_row, 24, "LINES", &err); + if (width) + *width = wh_helper(win.ws_col, 80, "COLUMNS", &err); + return err; } int FAST_FUNC tcsetattr_stdin_TCSANOW(const struct termios *tp) -- cgit v1.2.3