From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Mon, 19 Apr 2010 05:09:30 +0000 (-0700)
Subject: vi: discover window size even on serial consoles. optional
X-Git-Tag: 1_17_0~280
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=c175c4664734e5a363d8cc8668c08f551eff1485;p=oweals%2Fbusybox.git
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 <vda.linux@googlemail.com>
---
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);
diff --git a/libbb/read_key.c b/libbb/read_key.c
index 8422976c9..64557ab14 100644
--- a/libbb/read_key.c
+++ b/libbb/read_key.c
@@ -214,7 +214,7 @@ int64_t FAST_FUNC read_key(int fd, char *buffer, int timeout)
}
n++;
/* Try to decipher "ESC [ NNN ; NNN R" sequence */
- if (ENABLE_FEATURE_EDITING_ASK_TERMINAL
+ if ((ENABLE_FEATURE_EDITING_ASK_TERMINAL || ENABLE_FEATURE_VI_ASK_TERMINAL)
&& n >= 5
&& buffer[0] == '['
&& buffer[n-1] == 'R'
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)