tools: Add simple tool to retrieve the current cursor from X

Slightly more funky would be to poke around in the CRTC, but that should
require master. As it stands this should help verify that what X is
supplying to the driver matches user expectations

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

configure.ac

@@ -312,6 +312,9 @@ if test "x$tools" != "xno"; then
 		tools="no"
 	fi
 
+	PKG_CHECK_MODULES(TOOL_CURSOR, [xfixes x11 libpng], [cursor="yes"], [ivo="no"])
+	AM_CONDITIONAL(BUILD_TOOL_CURSOR, test "x$cursor" != "xno")
+
 	IVO_CFLAGS="$IVO_CFLAGS $extra_cflags"
 fi
 if test "x$tools" != "xno"; then

tools/.gitignore

@@ -1,3 +1,4 @@
+cursor
 dri3info
 intel-virtual-output
 org.x.xf86-video-intel.backlight-helper.policy

tools/Makefile.am

@@ -26,13 +26,21 @@ AM_CFLAGS = \
 drivermandir = $(DRIVER_MAN_DIR)
 policydir = $(datarootdir)/polkit-1/actions
 
+noinst_PROGRAMS =
+
 if BUILD_TOOLS
 bin_PROGRAMS = intel-virtual-output
 driverman_DATA = intel-virtual-output.$(DRIVER_MAN_SUFFIX)
 endif
 
+if BUILD_TOOL_CURSOR
+noinst_PROGRAMS += cursor
+cursor_CFLAGS = $(TOOL_CURSOR_CFLAGS)
+cursor_LDADD = $(TOOL_CURSOR_LIBS)
+endif
+
 if X11_DRI3
-noinst_PROGRAMS = dri3info
+noinst_PROGRAMS += dri3info
 dri3info_SOURCES = dri3info.c
 dri3info_CFLAGS = $(X11_DRI3_CFLAGS) $(DRI_CFLAGS)
 dri3info_LDADD = $(X11_DRI3_LIBS) $(DRI_LIBS)

tools/cursor.c

@@ -0,0 +1,107 @@
+/*
+ * Copyright © 2015 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <X11/Xlib.h>
+#include <X11/extensions/Xfixes.h>
+
+#include <stdio.h>
+#include <stdint.h>
+#include <png.h>
+
+int main(int argc, char **argv)
+{
+	Display *dpy;
+	XFixesCursorImage *cur;
+	unsigned long *src; /* XXX deep sigh */
+	unsigned x, y;
+	png_struct *png;
+	png_info *info;
+	png_byte **rows;
+	FILE *file;
+
+	dpy = XOpenDisplay(NULL);
+	if (dpy == NULL)
+		return 1;
+
+	if (!XFixesQueryExtension(dpy, (int *)&x, (int *)&y))
+		return 1;
+
+	cur = XFixesGetCursorImage(dpy);
+	if (cur == NULL)
+		return 1;
+
+	printf("Cursor on display '%s': %dx%d, (hotspot %dx%d)\n",
+	       DisplayString(dpy),
+	       cur->width, cur->height,
+	       cur->xhot, cur->yhot);
+
+	file = fopen("cursor.png", "wb");
+	if (file == NULL)
+		return 2;
+
+	png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+	info = png_create_info_struct(png);
+	png_init_io(png, file);
+	png_set_IHDR(png, info,
+		     cur->width, cur->height, 8,
+		     PNG_COLOR_TYPE_RGB_ALPHA,
+		     PNG_INTERLACE_NONE,
+		     PNG_COMPRESSION_TYPE_DEFAULT,
+		     PNG_FILTER_TYPE_DEFAULT);
+	png_write_info(png, info);
+
+	src = cur->pixels;
+	rows = malloc(cur->height*sizeof(png_byte*));
+	for (y = 0; y < cur->height; y++) {
+		rows[y] = malloc(cur->width * 4);
+		for (x = 0; x < cur->width; x++) {
+			uint32_t p = *src++;
+			uint8_t r = p >> 0;
+			uint8_t g = p >> 8;
+			uint8_t b = p >> 16;
+			uint8_t a = p >> 24;
+
+			if (a > 0x00 && a < 0xff) {
+				r = (r * 0xff + a /2) / a;
+				g = (g * 0xff + a /2) / a;
+				b = (b * 0xff + a /2) / a;
+			}
+
+			rows[y][4*x + 0] = b;
+			rows[y][4*x + 1] = g;
+			rows[y][4*x + 2] = r;
+			rows[y][4*x + 3] = a;
+		}
+	}
+
+	png_write_image(png, rows);
+	png_write_end(png, NULL);
+	fclose(file);
+
+	return 0;
+}