Support OSC 52 ? to read the top buffer inside tmux (when set-clipboard

is changed to on), also add refresh-client -l to ask tmux to use the
same mechanism to get the clipboard from the terminal outside
tmux. GitHub issue 1477.

cmd-refresh-client.c

@@ -31,8 +31,8 @@ const struct cmd_entry cmd_refresh_client_entry = {
 	.name = "refresh-client",
 	.alias = "refresh",
 
-	.args = { "C:St:", 0, 0 },
+	.args = { "C:lSt:", 0, 0 },
-	.usage = "[-S] [-C size] " CMD_TARGET_CLIENT_USAGE,
+	.usage = "[-lS] [-C size] " CMD_TARGET_CLIENT_USAGE,
 
 	.flags = CMD_AFTERHOOK,
 	.exec = cmd_refresh_client_exec
@@ -49,7 +49,10 @@ cmd_refresh_client_exec(struct cmd *self, struct cmdq_item *item)
 	if ((c = cmd_find_client(item, args_get(args, 't'), 0)) == NULL)
 		return (CMD_RETURN_ERROR);
 
-	if (args_has(args, 'C')) {
+	if (args_has(args, 'l')) {
+		if (c->session != NULL)
+			tty_putcode_ptr2(&c->tty, TTYC_MS, "", "?");
+	} else if (args_has(args, 'C')) {
 		if ((size = args_get(args, 'C')) == NULL) {
 			cmdq_error(item, "missing size");
 			return (CMD_RETURN_ERROR);

input.c

@@ -93,6 +93,10 @@ struct input_ctx {
 	u_char		       *input_buf;
 	size_t			input_len;
 	size_t			input_space;
+	enum {
+		INPUT_END_ST,
+		INPUT_END_BEL
+	}			input_end;
 
 	struct input_param	param_list[24];
 	u_int			param_list_len;
@@ -126,11 +130,11 @@ static void	input_set_state(struct window_pane *,
 		    const struct input_transition *);
 static void	input_reset_cell(struct input_ctx *);
 
-static void	input_osc_4(struct window_pane *, const char *);
+static void	input_osc_4(struct input_ctx *, const char *);
-static void	input_osc_10(struct window_pane *, const char *);
+static void	input_osc_10(struct input_ctx *, const char *);
-static void	input_osc_11(struct window_pane *, const char *);
+static void	input_osc_11(struct input_ctx *, const char *);
-static void	input_osc_52(struct window_pane *, const char *);
+static void	input_osc_52(struct input_ctx *, const char *);
-static void	input_osc_104(struct window_pane *, const char *);
+static void	input_osc_104(struct input_ctx *, const char *);
 
 /* Transition entry/exit handlers. */
 static void	input_clear(struct input_ctx *);
@@ -161,6 +165,7 @@ static void	input_csi_dispatch_sgr_rgb(struct input_ctx *, int, u_int *);
 static void	input_csi_dispatch_sgr(struct input_ctx *);
 static int	input_dcs_dispatch(struct input_ctx *);
 static int	input_top_bit_set(struct input_ctx *);
+static int	input_end_bel(struct input_ctx *);
 
 /* Command table comparison function. */
 static int	input_table_compare(const void *, const void *);
@@ -487,7 +492,7 @@ static const struct input_transition input_state_esc_enter_table[] = {
 	{ -1, -1, NULL, NULL }
 };
 
-/* esc_interm state table. */
+/* esc_intermediate state table. */
 static const struct input_transition input_state_esc_intermediate_table[] = {
 	INPUT_STATE_ANYWHERE,
 
@@ -602,7 +607,7 @@ static const struct input_transition input_state_dcs_parameter_table[] = {
 	{ -1, -1, NULL, NULL }
 };
 
-/* dcs_interm state table. */
+/* dcs_intermediate state table. */
 static const struct input_transition input_state_dcs_intermediate_table[] = {
 	INPUT_STATE_ANYWHERE,
 
@@ -655,12 +660,12 @@ static const struct input_transition input_state_dcs_ignore_table[] = {
 static const struct input_transition input_state_osc_string_table[] = {
 	INPUT_STATE_ANYWHERE,
 
-	{ 0x00, 0x06, NULL,	    NULL },
+	{ 0x00, 0x06, NULL,	     NULL },
-	{ 0x07, 0x07, NULL,	    &input_state_ground },
+	{ 0x07, 0x07, input_end_bel, &input_state_ground },
-	{ 0x08, 0x17, NULL,	    NULL },
+	{ 0x08, 0x17, NULL,	     NULL },
-	{ 0x19, 0x19, NULL,	    NULL },
+	{ 0x19, 0x19, NULL,	     NULL },
-	{ 0x1c, 0x1f, NULL,	    NULL },
+	{ 0x1c, 0x1f, NULL,	     NULL },
-	{ 0x20, 0xff, input_input,  NULL },
+	{ 0x20, 0xff, input_input,   NULL },
 
 	{ -1, -1, NULL, NULL }
 };
@@ -993,8 +998,8 @@ input_get(struct input_ctx *ictx, u_int validx, int minval, int defval)
 static void
 input_reply(struct input_ctx *ictx, const char *fmt, ...)
 {
-	va_list	ap;
+	va_list	 ap;
-	char   *reply;
+	char	*reply;
 
 	va_start(ap, fmt);
 	xvasprintf(&reply, fmt, ap);
@@ -1019,6 +1024,8 @@ input_clear(struct input_ctx *ictx)
 	*ictx->input_buf = '\0';
 	ictx->input_len = 0;
 
+	ictx->input_end = INPUT_END_ST;
+
 	ictx->flags &= ~INPUT_DISCARD;
 }
 
@@ -2046,6 +2053,17 @@ input_csi_dispatch_sgr(struct input_ctx *ictx)
 	}
 }
 
+/* End of input with BEL. */
+static int
+input_end_bel(struct input_ctx *ictx)
+{
+	log_debug("%s", __func__);
+
+	ictx->input_end = INPUT_END_BEL;
+
+	return (0);
+}
+
 /* DCS string started. */
 static void
 input_enter_dcs(struct input_ctx *ictx)
@@ -2102,7 +2120,8 @@ input_exit_osc(struct input_ctx *ictx)
 	if (ictx->input_len < 1 || *p < '0' || *p > '9')
 		return;
 
-	log_debug("%s: \"%s\"", __func__, p);
+	log_debug("%s: \"%s\" (end %s)", __func__, p,
+	    ictx->input_end == INPUT_END_ST ? "ST" : "BEL");
 
 	option = 0;
 	while (*p >= '0' && *p <= '9')
@@ -2119,23 +2138,23 @@ input_exit_osc(struct input_ctx *ictx)
 		}
 		break;
 	case 4:
-		input_osc_4(ictx->wp, p);
+		input_osc_4(ictx, p);
 		break;
 	case 10:
-		input_osc_10(ictx->wp, p);
+		input_osc_10(ictx, p);
 		break;
 	case 11:
-		input_osc_11(ictx->wp, p);
+		input_osc_11(ictx, p);
 		break;
 	case 12:
 		if (utf8_isvalid(p) && *p != '?') /* ? is colour request */
 			screen_set_cursor_colour(ictx->ctx.s, p);
 		break;
 	case 52:
-		input_osc_52(ictx->wp, p);
+		input_osc_52(ictx, p);
 		break;
 	case 104:
-		input_osc_104(ictx->wp, p);
+		input_osc_104(ictx, p);
 		break;
 	case 112:
 		if (*p == '\0') /* no arguments allowed */
@@ -2237,11 +2256,12 @@ input_top_bit_set(struct input_ctx *ictx)
 
 /* Handle the OSC 4 sequence for setting (multiple) palette entries. */
 static void
-input_osc_4(struct window_pane *wp, const char *p)
+input_osc_4(struct input_ctx *ictx, const char *p)
 {
-	char	*copy, *s, *next = NULL;
+	struct window_pane	*wp = ictx->wp;
-	long	 idx;
+	char			*copy, *s, *next = NULL;
-	u_int	 r, g, b;
+	long	 		idx;
+	u_int			 r, g, b;
 
 	copy = s = xstrdup(p);
 	while (s != NULL && *s != '\0') {
@@ -2271,9 +2291,10 @@ bad:
 
 /* Handle the OSC 10 sequence for setting foreground colour. */
 static void
-input_osc_10(struct window_pane *wp, const char *p)
+input_osc_10(struct input_ctx *ictx, const char *p)
 {
-	u_int	 r, g, b;
+	struct window_pane	*wp = ictx->wp;
+	u_int			 r, g, b;
 
 	if (sscanf(p, "rgb:%2x/%2x/%2x", &r, &g, &b) != 3)
 	    goto bad;
@@ -2289,9 +2310,10 @@ bad:
 
 /* Handle the OSC 11 sequence for setting background colour. */
 static void
-input_osc_11(struct window_pane *wp, const char *p)
+input_osc_11(struct input_ctx *ictx, const char *p)
 {
-	u_int	 r, g, b;
+	struct window_pane	*wp = ictx->wp;
+	u_int			 r, g, b;
 
 	if (sscanf(p, "rgb:%2x/%2x/%2x", &r, &g, &b) != 3)
 	    goto bad;
@@ -2307,13 +2329,16 @@ bad:
 
 /* Handle the OSC 52 sequence for setting the clipboard. */
 static void
-input_osc_52(struct window_pane *wp, const char *p)
+input_osc_52(struct input_ctx *ictx, const char *p)
 {
+	struct window_pane	*wp = ictx->wp;
 	char			*end;
+	const char		*buf;
 	size_t			 len;
 	u_char			*out;
 	int			 outlen, state;
 	struct screen_write_ctx	 ctx;
+	struct paste_buffer	*pb;
 
 	state = options_get_number(global_options, "set-clipboard");
 	if (state != 2)
@@ -2324,6 +2349,32 @@ input_osc_52(struct window_pane *wp, const char *p)
 	end++;
 	if (*end == '\0')
 		return;
+	log_debug("%s: %s", __func__, end);
+
+	if (strcmp(end, "?") == 0) {
+		if ((pb = paste_get_top(NULL)) != NULL) {
+			buf = paste_buffer_data(pb, &len);
+			outlen = 4 * ((len + 2) / 3) + 1;
+			out = xmalloc(outlen);
+			if ((outlen = b64_ntop(buf, len, out, outlen)) == -1) {
+				abort();
+				free(out);
+				return;
+			}
+		} else {
+			outlen = 0;
+			out = NULL;
+		}
+		bufferevent_write(wp->event, "\033]52;;", 6);
+		if (outlen != 0)
+			bufferevent_write(wp->event, out, outlen);
+		if (ictx->input_end == INPUT_END_BEL)
+			bufferevent_write(wp->event, "\007", 1);
+		else
+			bufferevent_write(wp->event, "\033\\", 2);
+		free(out);
+		return;
+	}
 
 	len = (strlen(end) / 4) * 3;
 	if (len == 0)
@@ -2345,10 +2396,11 @@ input_osc_52(struct window_pane *wp, const char *p)
 
 /* Handle the OSC 104 sequence for unsetting (multiple) palette entries. */
 static void
-input_osc_104(struct window_pane *wp, const char *p)
+input_osc_104(struct input_ctx *ictx, const char *p)
 {
-	char	*copy, *s;
+	struct window_pane	*wp = ictx->wp;
-	long	idx;
+	char			*copy, *s;
+	long			idx;
 
 	if (*p == '\0') {
 		window_pane_reset_palette(wp);

tmux.1

@@ -917,8 +917,8 @@ is used, the
 .Ic update-environment
 option will not be applied.
 .It Xo Ic refresh-client
+.Op Fl lS
 .Op Fl C Ar width,height
-.Op Fl S
 .Op Fl t Ar target-client
 .Xc
 .D1 (alias: Ic refresh )
@@ -931,6 +931,10 @@ is specified, only update the client's status line.
 .Pp
 .Fl C
 sets the width and height of a control client.
+.Fl l
+requests the clipboard from the client using the
+.Xr xterm 1
+escape sequence and stores it in a new paste buffer.
 .It Xo Ic rename-session
 .Op Fl t Ar target-session
 .Ar new-name
@@ -3890,7 +3894,7 @@ option.
 .El
 .Pp
 When a pane is first created, its title is the hostname.
-A pane's title can be set via the OSC title setting sequence, for example:
+A pane's title can be set via the title setting escape sequence, for example:
 .Bd -literal -offset indent
 $ printf '\e033]2;My Title\e033\e\e'
 .Ed
@@ -4444,7 +4448,7 @@ Indicate that the terminal supports the
 .Ql direct colour
 RGB escape sequence (for example, \ee[38;2;255;255;255m).
 .Pp
-If supported, this is used for the OSC initialize colour escape sequence (which
+If supported, this is used for the initialize colour escape sequence (which
 may be enabled by adding the
 .Ql initc
 and

tty-keys.c

@@ -19,7 +19,10 @@
 #include <sys/types.h>
 #include <sys/time.h>
 
+#include <netinet/in.h>
+
 #include <limits.h>
+#include <resolv.h>
 #include <stdlib.h>
 #include <string.h>
 #include <termios.h>
@@ -44,6 +47,8 @@ static int	tty_keys_next1(struct tty *, const char *, size_t, key_code *,
 		    size_t *, int);
 static void	tty_keys_callback(int, short, void *);
 static int	tty_keys_mouse(struct tty *, const char *, size_t, size_t *);
+static int	tty_keys_clipboard(struct tty *, const char *, size_t,
+		    size_t *);
 static int	tty_keys_device_attributes(struct tty *, const char *, size_t,
 		    size_t *);
 
@@ -571,6 +576,17 @@ tty_keys_next(struct tty *tty)
 		return (0);
 	log_debug("%s: keys are %zu (%.*s)", c->name, len, (int)len, buf);
 
+	/* Is this a clipboard response? */
+	switch (tty_keys_clipboard(tty, buf, len, &size)) {
+	case 0:		/* yes */
+		key = KEYC_UNKNOWN;
+		goto complete_key;
+	case -1:	/* no, or not valid */
+		break;
+	case 1:		/* partial */
+		goto partial_key;
+	}
+
 	/* Is this a device attributes response? */
 	switch (tty_keys_device_attributes(tty, buf, len, &size)) {
 	case 0:		/* yes */
@@ -871,6 +887,93 @@ tty_keys_mouse(struct tty *tty, const char *buf, size_t len, size_t *size)
 	return (0);
 }
 
+/*
+ * Handle OSC 52 clipboard input. Returns 0 for success, -1 for failure, 1 for
+ * partial.
+ */
+static int
+tty_keys_clipboard(__unused struct tty *tty, const char *buf, size_t len,
+    size_t *size)
+{
+	size_t	 end, terminator, needed;
+	char	*copy, *out;
+	int	 outlen;
+
+	*size = 0;
+
+	/* First three bytes are always \033]52;. */
+	if (buf[0] != '\033')
+		return (-1);
+	if (len == 1)
+		return (1);
+	if (buf[1] != ']')
+		return (-1);
+	if (len == 2)
+		return (1);
+	if (buf[2] != '5')
+		return (-1);
+	if (len == 3)
+		return (1);
+	if (buf[3] != '2')
+		return (-1);
+	if (len == 4)
+		return (1);
+	if (buf[4] != ';')
+		return (-1);
+	if (len == 5)
+		return (1);
+
+	/* Find the terminator if any. */
+	for (end = 5; end < len; end++) {
+		if (buf[end] == '\007') {
+			terminator = 1;
+			break;
+		}
+		if (end > 5 && buf[end - 1] == '\033' && buf[end] == '\\') {
+			terminator = 2;
+			break;
+		}
+	}
+	if (end == len)
+		return (1);
+	*size = end + terminator;
+
+	/* Skip the initial part. */
+	buf += 5;
+	end -= 5;
+
+	/* Get the second argument. */
+	while (end != 0 && *buf != ';') {
+		buf++;
+		end--;
+	}
+	if (end == 0 || end == 1)
+		return (0);
+	buf++;
+	end--;
+
+	/* It has to be a string so copy it. */
+	copy = xmalloc(end + 1);
+	memcpy(copy, buf, end);
+	copy[end] = '\0';
+
+	/* Convert from base64. */
+	needed = (end / 4) * 3;
+	out = xmalloc(needed);
+	if ((outlen = b64_pton(copy, out, len)) == -1) {
+		free(out);
+		free(copy);
+		return (0);
+	}
+	free(copy);
+
+	/* Create a new paste buffer. */
+	log_debug("%s: %.*s", __func__, outlen, out);
+	paste_add(out, outlen);
+
+	return (0);
+}
+
 /*
  * Handle device attributes input. Returns 0 for success, -1 for failure, 1 for
  * partial.