On Tuesday 20 July 2010 03:19, Rob Landley wrote: > > http://busybox.net/downloads/fixes-1.17.0/busybox-1.17.0-ask_terminal.patch > > > > This patch will make e.g. hush to query window width using ESC [ 6 n > > only if ioctl(TIOCGWINSZ) fails or returns bogus value of 0. > > > > You need to not only confirm that it builds, but also try it > > on the serial line and let me know whether it actually > > does the trick. It may fail to work if ctl(TIOCGWINSZ) on the serial > > line lies, that is, returns some invented nonzero width and height > > and doesnt indicate the error. > > Ok, let's see.... > > Nope, vi still thinks it's 80x25. (Which is odd because > CONFIG_FEATURE_VI_ASK_TERMINAL is enabled.) > > Let's see... the ioctl is returning 0 (success) but leaving win.ws_row and > win.ws_col at 0 if they were initialized to 0. And your code is washing that > through: > > static int wh_helper(int value, int def_val, const char *env_name, int *err) > { > 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; ** note that this *err = 0 thing happens _only_ if LINES/COLUMNS are overridded in environment. > } > } > if (value <= 1 || value >= 30000) > value = def_val; > return value; > } > > Which is helpfully overwriting those 0 values with a default value.
Hmmm, it should be a bug then, but I don't see where: 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; err = ioctl(fd, TIOCGWINSZ, &win) != 0 || win.ws_row == 0; ** we get err = 1 here, since 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); ** and here wh_helper() should NOT reset err to 0, unless you have $COLUMNS defined in environment. return err; ** we return 1 } ... static void win_changed(int nsig) { int sv_errno = errno; unsigned width; IF_FEATURE_EDITING_ASK_TERMINAL(S.unknown_width =) get_terminal_width_height(0, &width, NULL); ** and here S.unknown_width should be set to 1 cmdedit_setwidth(width, nsig /* - just a yes/no flag */); if (nsig == SIGWINCH) signal(SIGWINCH, win_changed); /* rearm ourself */ errno = sv_errno; } Apparently it doesn't happen. Where is my mistake? -- vda _______________________________________________ busybox mailing list busybox@busybox.net http://lists.busybox.net/mailman/listinfo/busybox