Adding gaps support and more.

• Adding support for gaps (#3)
• Adding more comments and categorizing function declarations.
• Adding support for EWMH properties (xmenu look is now consistent
  in some window compositors).
• Changing how configuration is done (now all configuration belongs
  to the config structure).

xmenu.h

@@ -0,0 +1,80 @@
+#define PROGNAME "xmenu"
+
+/* macros for keyboard menu navigation */
+#define ITEMPREV 0
+#define ITEMNEXT 1
+
+/* macros */
+#define LEN(x) (sizeof (x) / sizeof (x[0]))
+#define MAX(x,y) ((x)>(y)?(x):(y))
+#define MIN(x,y) ((x)<(y)?(x):(y))
+
+/* color enum */
+enum {ColorFG, ColorBG, ColorLast};
+
+/* EWMH atoms */
+enum {NetWMName, NetWMWindowType, NetWMWindowTypePopupMenu, NetLast};
+
+/* configuration structure */
+struct Config {
+	const char *font;
+
+	const char *background_color;
+	const char *foreground_color;
+	const char *selbackground_color;
+	const char *selforeground_color;
+	const char *separator_color;
+	const char *border_color;
+
+	int width_pixels;
+	int height_pixels;
+	int border_pixels;
+	int separator_pixels;
+	int gap_pixels;
+
+	int triangle_width;
+	int triangle_height;
+
+	int iconpadding;
+
+	int cursx, cursy;           /* cursor position */
+	int screenw, screenh;       /* screen width and height */
+};
+
+/* draw context structure */
+struct DC {
+	XftColor normal[ColorLast];
+	XftColor selected[ColorLast];
+	XftColor border;
+	XftColor separator;
+
+	GC gc;
+	XftFont *font;
+};
+
+/* menu item structure */
+struct Item {
+	char *label;            /* string to be drawed on menu */
+	char *output;           /* string to be outputed when item is clicked */
+	char *file;             /* filename of the icon */
+	int y;                  /* item y position relative to menu */
+	int h;                  /* item height */
+	size_t labellen;        /* strlen(label) */
+	struct Item *prev;      /* previous item */
+	struct Item *next;      /* next item */
+	struct Menu *submenu;   /* submenu spawned by clicking on item */
+	Imlib_Image icon;
+};
+
+/* menu structure */
+struct Menu {
+	struct Menu *parent;    /* parent menu */
+	struct Item *caller;    /* item that spawned the menu */
+	struct Item *list;      /* list of items contained by the menu */
+	struct Item *selected;  /* item currently selected in the menu */
+	int x, y, w, h;         /* menu geometry */
+	unsigned level;         /* menu level relative to root */
+	Drawable pixmap;        /* pixmap to draw the menu on */
+	XftDraw *draw;
+	Window win;             /* menu window to map on the screen */
+};