[vte] emulation: Fix mouse mode 1003 to correctly report if no button is pressed

[Egmont Koblinger <egmontkob src gnome org>]

commit 3448a1dbbd0e8af558d25f9eb4195f699e7e288b
Author: Egmont Koblinger <egmont gmail com>
Date:   Fri Feb 27 11:57:56 2015 +0100

    emulation: Fix mouse mode 1003 to correctly report if no button is pressed
    
    https://bugzilla.gnome.org/show_bug.cgi?id=745074

 src/vte-private.h |    2 +-
 src/vte.c         |   29 ++++++++++++++++++++++-------
 2 files changed, 23 insertions(+), 8 deletions(-)
---
diff --git a/src/vte-private.h b/src/vte-private.h
index 43d2266..e05216f 100644
--- a/src/vte-private.h
+++ b/src/vte-private.h
@@ -357,7 +357,7 @@ struct _VteTerminalPrivate {
 
        int mouse_tracking_mode; /* this is of type MouseTrackingMode,
                                    but we need to guarantee its type. */
-       guint mouse_last_button;
+        guint mouse_pressed_buttons;      /* bits 0, 1, 2 resp. for buttons 1, 2, 3 */
        long mouse_last_x, mouse_last_y;
        gboolean mouse_autohide;
        guint mouse_autoscroll_tag;
diff --git a/src/vte.c b/src/vte.c
index d49fccd..465f632 100644
--- a/src/vte.c
+++ b/src/vte.c
@@ -5507,6 +5507,9 @@ vte_terminal_feed_mouse_event(VteTerminal *terminal,
 
        /* Encode the button information in cb. */
        switch (button) {
+        case 0:                 /* No button, just dragging. */
+                cb = 3;
+                break;
        case 1:                 /* Left. */
                cb = 0;
                break;
@@ -5640,6 +5643,7 @@ vte_terminal_maybe_send_mouse_drag(VteTerminal *terminal, GdkEventMotion *event)
        int height = terminal->pvt->char_height;
        long col = ((long) event->x - terminal->pvt->padding.left) / width;
        long row = ((long) event->y - terminal->pvt->padding.top) / height;
+        int button;
 
        /* First determine if we even want to send notification. */
        switch (event->type) {
@@ -5649,7 +5653,7 @@ vte_terminal_maybe_send_mouse_drag(VteTerminal *terminal, GdkEventMotion *event)
 
                if (terminal->pvt->mouse_tracking_mode < MOUSE_TRACKING_ALL_MOTION_TRACKING) {
 
-                       if (terminal->pvt->mouse_last_button == 0) {
+                        if (terminal->pvt->mouse_pressed_buttons == 0) {
                                return FALSE;
                        }
                        /* the xterm doc is not clear as to whether
@@ -5664,7 +5668,16 @@ vte_terminal_maybe_send_mouse_drag(VteTerminal *terminal, GdkEventMotion *event)
                break;
        }
 
-       vte_terminal_feed_mouse_event(terminal, terminal->pvt->mouse_last_button,
+        /* As per xterm, report the leftmost pressed button - if any. */
+        if (terminal->pvt->mouse_pressed_buttons & 1)
+                button = 1;
+        else if (terminal->pvt->mouse_pressed_buttons & 2)
+                button = 2;
+        else if (terminal->pvt->mouse_pressed_buttons & 4)
+                button = 3;
+        else
+                button = 0;
+        vte_terminal_feed_mouse_event(terminal, button,
                                      TRUE /* drag */, FALSE /* not release */,
                                      col, row);
        return TRUE;
@@ -7023,7 +7036,7 @@ vte_terminal_motion_notify(GtkWidget *widget, GdkEventMotion *event)
 
        vte_terminal_read_modifiers (terminal, (GdkEvent*) event);
 
-       if (terminal->pvt->mouse_last_button) {
+        if (terminal->pvt->mouse_pressed_buttons != 0) {
                vte_terminal_match_hilite_hide (terminal);
        } else {
                /* Hilite any matches. */
@@ -7244,7 +7257,8 @@ vte_terminal_button_press(GtkWidget *widget, GdkEventButton *event)
        }
 
        /* Save the pointer state for later use. */
-       terminal->pvt->mouse_last_button = event->button;
+        if (event->button >= 1 && event->button <= 3)
+                terminal->pvt->mouse_pressed_buttons |= (1 << (event->button - 1));
        terminal->pvt->mouse_last_x = x;
        terminal->pvt->mouse_last_y = y;
 
@@ -7297,7 +7311,8 @@ vte_terminal_button_release(GtkWidget *widget, GdkEventButton *event)
        }
 
        /* Save the pointer state for later use. */
-       terminal->pvt->mouse_last_button = 0;
+        if (event->button >= 1 && event->button <= 3)
+                terminal->pvt->mouse_pressed_buttons &= ~(1 << (event->button - 1));
        terminal->pvt->mouse_last_x = x;
        terminal->pvt->mouse_last_y = y;
        terminal->pvt->selecting_after_threshold = FALSE;
@@ -7357,7 +7372,7 @@ vte_terminal_focus_out(GtkWidget *widget, GdkEventFocus *event)
                vte_terminal_match_hilite_hide (terminal);
                /* Mark the cursor as invisible to disable hilite updating */
                terminal->pvt->mouse_cursor_visible = FALSE;
-               terminal->pvt->mouse_last_button = 0;
+                terminal->pvt->mouse_pressed_buttons = 0;
        }
 
        terminal->pvt->has_focus = FALSE;
@@ -11948,7 +11963,7 @@ vte_terminal_reset(VteTerminal *terminal,
        }
        /* Reset mouse motion events. */
        pvt->mouse_tracking_mode = MOUSE_TRACKING_NONE;
-       pvt->mouse_last_button = 0;
+        pvt->mouse_pressed_buttons = 0;
        pvt->mouse_last_x = 0;
        pvt->mouse_last_y = 0;
        pvt->mouse_xterm_extension = FALSE;