1 files changed, 135 insertions, 0 deletions
diff --git a/gfx/x11.c b/gfx/x11.c
new file mode 100644
index 00000000..eae926c2
--- /dev/null
+++ b/gfx/x11.c
@@ -0,0 +1,135 @@
+/* Copyright (c) 2018, June McEnroe <programble@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <X11/Xlib.h>
+#include <err.h>
+#include <sysexits.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+#include "gfx.h"
+
+static size_t width = 800;
+static size_t height = 600;
+
+static Display *display;
+static Window window;
+static Atom WM_DELETE_WINDOW;
+static GC windowGc;
+static XImage *image;
+
+static size_t bufSize;
+static uint32_t *buf;
+
+static size_t pixmapWidth;
+static size_t pixmapHeight;
+static Pixmap pixmap;
+
+static void createWindow(void) {
+	display = XOpenDisplay(NULL);
+	if (!display) errx(EX_UNAVAILABLE, "XOpenDisplay: %s", XDisplayName(NULL));
+
+	Window root = DefaultRootWindow(display);
+	window = XCreateSimpleWindow(display, root, 0, 0, width, height, 0, 0, 0);
+
+	WM_DELETE_WINDOW = XInternAtom(display, "WM_DELETE_WINDOW", false);
+	XSetWMProtocols(display, window, &WM_DELETE_WINDOW, 1);
+
+	windowGc = XCreateGC(display, window, 0, NULL);
+
+	image = XCreateImage(display, NULL, 24, ZPixmap, 0, NULL, width, height, 32, 0);
+}
+
+static void resizePixmap(void) {
+	size_t newSize = 4 * width * height;
+	if (newSize > bufSize) {
+		bufSize = newSize;
+		free(buf);
+		buf = malloc(bufSize);
+		if (!buf) err(EX_OSERR, "malloc(%zu)", bufSize);
+	}
+
+	image->data = (char *)buf;
+	image->width = width;
+	image->height = height;
+	image->bytes_per_line = 4 * width;
+
+	if (width > pixmapWidth || height > pixmapHeight) {
+		pixmapWidth = width;
+		pixmapHeight = height;
+		if (pixmap) XFreePixmap(display, pixmap);
+		pixmap = XCreatePixmap(display, window, pixmapWidth, pixmapHeight, 24);
+	}
+}
+
+static void drawWindow(void) {
+	draw(buf, width, height);
+	XPutImage(display, pixmap, windowGc, image, 0, 0, 0, 0, width, height);
+	XCopyArea(display, pixmap, window, windowGc, 0, 0, width, height, 0, 0);
+}
+
+int main(int argc, char *argv[]) {
+	int error = init(argc, argv);
+	if (error) return error;
+
+	createWindow();
+	resizePixmap();
+	drawWindow();
+
+	XStoreName(display, window, status());
+	XMapWindow(display, window);
+
+	XEvent event;
+	XSelectInput(display, window, ExposureMask | StructureNotifyMask | KeyPressMask);
+	for (;;) {
+		XNextEvent(display, &event);
+
+		switch (event.type) {
+			case KeyPress: {
+				XKeyEvent key = event.xkey;
+				KeySym sym = XLookupKeysym(&key, key.state & ShiftMask);
+				if (sym > 0x80) break;
+				if (!input(sym)) return EX_OK;
+				drawWindow();
+				XStoreName(display, window, status());
+			} break;
+
+			case ConfigureNotify: {
+				XConfigureEvent configure = event.xconfigure;
+				width = configure.width;
+				height = configure.height;
+				resizePixmap();
+				drawWindow();
+			} break;
+
+			case Expose: {
+				XExposeEvent expose = event.xexpose;
+				XCopyArea(
+					display, pixmap, window, windowGc,
+					expose.x, expose.y,
+					expose.width, expose.height,
+					expose.x, expose.y
+				);
+			} break;
+
+			case ClientMessage: {
+				XClientMessageEvent client = event.xclient;
+				if ((Atom)client.data.l[0] == WM_DELETE_WINDOW) return EX_OK;
+			} break;
+		}
+	}
+}