Function checkBufferColor

server/eglxfakerut.cpp:141–174

unsigned int checkBufferColor(void)
{
	int i, viewport[4], ps = 3;  unsigned int ret = 0;
	unsigned char *buf = NULL;

	try
	{
		viewport[0] = viewport[1] = viewport[2] = viewport[3] = 0;
		glGetIntegerv(GL_VIEWPORT, viewport);
		if(viewport[2] < 1 || viewport[3] < 1)
			THROW("Invalid viewport dimensions");

		if((buf = (unsigned char *)malloc(viewport[2] * viewport[3] * ps)) == NULL)
			THROW("Could not allocate buffer");
		memset(buf, 128, viewport[2] * viewport[3] * ps);

		glPixelStorei(GL_PACK_ALIGNMENT, 1);
		glReadPixels(0, 0, viewport[2], viewport[3], GL_RGB, GL_UNSIGNED_BYTE,
			buf);
		for(i = 3; i < viewport[2] * viewport[3] * ps; i += ps)
		{
			if(buf[i] != buf[0] || buf[i + 1] != buf[1] || buf[i + 2] != buf[2])
				THROW("Bogus data read back");
		}
		ret = buf[0] | (buf[1] << 8) | (buf[2] << 16);
		free(buf);
		return ret;
	}
	catch(...)
	{
		free(buf);
		throw;
	}
}


void checkWindowColor(Display *dpy, Window win, unsigned int color)