awesome: add selection() for getting the primary X selection

Signed-off-by: Gregor Best <farhaven@googlemail.com>
Signed-off-by: Julien Danjou <julien@danjou.info>

CMakeLists.txt

@@ -54,6 +54,7 @@ set(AWE_SRCS
     ${SOURCE_DIR}/mouse.c
     ${SOURCE_DIR}/screen.c
     ${SOURCE_DIR}/stack.c
+    ${SOURCE_DIR}/selection.c
     ${SOURCE_DIR}/wibox.c
     ${SOURCE_DIR}/systray.c
     ${SOURCE_DIR}/tag.c

common/atoms.list

@@ -54,3 +54,4 @@ _NET_SYSTEM_TRAY_ORIENTATION
 WM_CHANGE_STATE
 WM_WINDOW_ROLE
 WM_CLIENT_LEADER
+XSEL_DATA

luaa.c

@@ -76,6 +76,8 @@ extern const struct luaL_reg awesome_wibox_meta[];
 extern const struct luaL_reg awesome_key_methods[];
 extern const struct luaL_reg awesome_key_meta[];
 extern const struct luaL_reg awesome_keybinding_methods[];
+extern const struct luaL_reg awesome_selection_methods[];
+extern const struct luaL_reg awesome_selection_meta[];
 
 static struct sockaddr_un *addr;
 static ev_io csio = { .fd = -1 };
@@ -840,6 +842,9 @@ luaA_init(void)
     luaA_openlib(L, "key", awesome_key_methods, awesome_key_meta);
     luaA_openlib(L, "keybinding", awesome_keybinding_methods, awesome_key_meta);
 
+    /* Export selection */
+    luaA_openlib(L, "selection", awesome_selection_methods, awesome_selection_meta);
+
     lua_pushliteral(L, "AWESOME_VERSION");
     lua_pushstring(L, AWESOME_VERSION);
     lua_settable(L, LUA_GLOBALSINDEX);

selection.c

@@ -0,0 +1,129 @@
+/*
+ * selection.c - Selection handling
+ *
+ * Copyright © 2009 Julien Danjou <julien@danjou.info>
+ * Copyright © 2009 Gregor Best <farhaven@googlemail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <xcb/xcb_atom.h>
+
+#include "structs.h"
+#include "event.h"
+#include "common/atoms.h"
+
+extern awesome_t globalconf;
+
+static xcb_window_t selection_window = XCB_NONE;
+
+/** Get the current X selection buffer.
+ * \param L The Lua VM state.
+ * \return The number of elements pushed on stack.
+ * \luastack
+ * \lreturn A string with the current X selection buffer.
+ */
+static int
+luaA_selection_get(lua_State *L)
+{
+    if(selection_window == XCB_NONE)
+    {
+        xcb_screen_t *screen = xutil_screen_get(globalconf.connection, globalconf.default_screen);
+        uint32_t mask = XCB_CW_BACK_PIXEL | XCB_CW_OVERRIDE_REDIRECT | XCB_CW_EVENT_MASK;
+        uint32_t values[] = { screen->black_pixel, 1, XCB_EVENT_MASK_PROPERTY_CHANGE };
+
+        selection_window = xcb_generate_id(globalconf.connection);
+
+        xcb_create_window(globalconf.connection, screen->root_depth, selection_window, screen->root,
+                          0, 0, 1, 1, 0, XCB_COPY_FROM_PARENT, screen->root_visual,
+                          mask, values);
+    }
+
+    xcb_convert_selection(globalconf.connection, selection_window,
+                          PRIMARY, UTF8_STRING, XSEL_DATA, XCB_CURRENT_TIME);
+    xcb_flush(globalconf.connection);
+
+    xcb_generic_event_t *event;
+
+    while(true)
+    {
+        event = xcb_wait_for_event(globalconf.connection);
+
+        if(!event)
+            return 0;
+
+        if(XCB_EVENT_RESPONSE_TYPE(event) != XCB_SELECTION_NOTIFY)
+        {
+            /* \todo Eventually, this may be rewritten with adding a static
+             * buffer, then a event handler for XCB_SELECTION_NOTIFY, then call
+             * xcb_event_poll_for_event_loop() and awesome_refresh(),
+             * then check if some static buffer has been filled with data.
+             * If yes, that'd be the xsel data, otherwise, re-loop.
+             * Anyway that's still brokes the socket or D-Bus, so maybe using
+             * ev_loop() would be even better.
+             */
+            xcb_event_handle(&globalconf.evenths, event);
+            p_delete(&event);
+            awesome_refresh(globalconf.connection);
+            continue;
+        }
+
+        xcb_selection_notify_event_t *event_notify =
+            (xcb_selection_notify_event_t *) event;
+
+        if(event_notify->selection == PRIMARY
+           && event_notify->property != XCB_NONE)
+        {
+            xcb_get_text_property_reply_t prop;
+            xcb_get_property_cookie_t cookie =
+                xcb_get_text_property(globalconf.connection,
+                                      event_notify->requestor,
+                                      event_notify->property);
+
+            if(xcb_get_text_property_reply(globalconf.connection,
+                                           cookie, &prop, NULL))
+            {
+                lua_pushlstring(L, prop.name, prop.name_len);
+
+                xcb_get_text_property_reply_wipe(&prop);
+
+                xcb_delete_property(globalconf.connection,
+                                    event_notify->requestor,
+                                    event_notify->property);
+
+                p_delete(&event);
+
+                return 1;
+            }
+            else
+                break;
+        }
+    }
+
+    p_delete(&event);
+    return 0;
+}
+
+const struct luaL_reg awesome_selection_methods[] =
+{
+    { "__call", luaA_selection_get },
+    { NULL, NULL }
+};
+
+const struct luaL_reg awesome_selection_meta[] =
+{
+    { NULL, NULL }
+};