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 --- editors/Config.in | 12 ++++++++++++ editors/vi.c | 23 ++++++++++++++++++++++- 2 files changed, 34 insertions(+), 1 deletion(-) (limited to 'editors') diff --git a/editors/Config.in b/editors/Config.in index e4fdd0f38..5f9566f0a 100644 --- a/editors/Config.in +++ b/editors/Config.in @@ -168,6 +168,18 @@ config FEATURE_VI_WIN_RESIZE help Make busybox vi behave nicely with terminals that get resized. +config FEATURE_VI_ASK_TERMINAL + bool "Use 'tell me cursor position' ESC sequence to measure window" + default n + depends on VI + help + If terminal size can't be retrieved and $LINES/$COLUMNS are not set, + this option makes vi perform a last-ditch effort to find it: + vi positions cursor to 999,999 and asks terminal to report real + cursor position using "ESC [ 6 n" escape sequence, then reads stdin. + + This is not clean but helps a lot on serial lines and such. + config FEATURE_VI_OPTIMIZE_CURSOR bool "Optimize cursor movement" default y diff --git a/editors/vi.c b/editors/vi.c index f925984ba..d3a35e781 100644 --- a/editors/vi.c +++ b/editors/vi.c @@ -138,6 +138,9 @@ struct globals { int save_argc; // how many file names on cmd line int cmdcnt; // repetition count unsigned rows, columns; // the terminal screen is this size +#if ENABLE_FEATURE_VI_ASK_TERMINAL + int get_rowcol_error; +#endif int crow, ccol; // cursor is on Crow x Ccol int offset; // chars scrolled off the screen to the left int have_status_msg; // is default edit status needed? @@ -503,7 +506,11 @@ static int init_text_buffer(char *fn) #if ENABLE_FEATURE_VI_WIN_RESIZE static void query_screen_dimensions(void) { - get_terminal_width_height(STDIN_FILENO, &columns, &rows); +# if ENABLE_FEATURE_VI_ASK_TERMINAL + if (!G.get_rowcol_error) + G.get_rowcol_error = +# endif + get_terminal_width_height(STDIN_FILENO, &columns, &rows); if (rows > MAX_SCR_ROWS) rows = MAX_SCR_ROWS; if (columns > MAX_SCR_COLS) @@ -530,6 +537,20 @@ static void edit_file(char *fn) columns = 80; size = 0; query_screen_dimensions(); +#if ENABLE_FEATURE_VI_ASK_TERMINAL + if (G.get_rowcol_error /* TODO? && no input on stdin */) { + uint64_t k; + write1("\033[999;999H" "\033[6n"); + fflush_all(); + k = read_key(STDIN_FILENO, readbuffer, /*timeout_ms:*/ 100); + if ((int32_t)k == KEYCODE_CURSOR_POS) { + uint32_t rc = (k >> 32); + columns = (rc & 0x7fff); + rows = ((rc >> 16) & 0x7fff); + } + query_screen_dimensions(); + } +#endif new_screen(rows, columns); // get memory for virtual screen init_text_buffer(fn); -- cgit v1.2.3