LibC+Kernel: Move GPU-related API methods to a LibC header file

The Kernel/API directory in general shouldn't include userspace code,
but structure definitions that both are shared between the Kernel and
userspace.

All users of the ioctl API obviously use LibC so LibC is the most common
and shared library for the affected programs.

Userland/Libraries/LibC/sys/devices/gpu.h

@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/DeprecatedString.h>
+#include <AK/Platform.h>
+#include <AK/ScopeGuard.h>
+#include <fcntl.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <sys/cdefs.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <unistd.h>
+
+__BEGIN_DECLS
+
+ALWAYS_INLINE int graphics_connector_get_properties(int fd, GraphicsConnectorProperties* info)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_GET_PROPERTIES, info);
+}
+
+ALWAYS_INLINE int graphics_connector_get_head_edid(int fd, GraphicsHeadEDID* info)
+{
+    // FIXME: Optimize this function to get a minor number instead of a file descriptor.
+    struct stat display_connector_stat;
+    if (auto rc = fstat(fd, &display_connector_stat); rc < 0) {
+        return rc;
+    }
+    auto minor_number = minor(display_connector_stat.st_rdev);
+
+    auto edid_fd = open(DeprecatedString::formatted("/sys/devices/graphics/connectors/{}/edid", minor_number).characters(), O_RDONLY);
+    if (edid_fd < 0) {
+        return edid_fd;
+    }
+
+    ScopeGuard close_on_return([&]() {
+        close(edid_fd);
+    });
+
+    if (auto rc = read(edid_fd, info->bytes, info->bytes_size); rc < 0) {
+        return rc;
+    }
+
+    return 0;
+}
+
+ALWAYS_INLINE int graphics_connector_set_responsible(int fd)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_SET_RESPONSIBLE, nullptr);
+}
+
+ALWAYS_INLINE int graphics_connector_unset_responsible(int fd)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_UNSET_RESPONSIBLE, nullptr);
+}
+
+ALWAYS_INLINE int fb_get_head_vertical_offset_buffer(int fd, GraphicsHeadVerticalOffset* vertical_offset)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_GET_HEAD_VERTICAL_OFFSET_BUFFER, vertical_offset);
+}
+
+ALWAYS_INLINE int fb_set_head_vertical_offset_buffer(int fd, GraphicsHeadVerticalOffset* vertical_offset)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_SET_HEAD_VERTICAL_OFFSET_BUFFER, vertical_offset);
+}
+
+ALWAYS_INLINE int graphics_connector_set_head_mode_setting(int fd, GraphicsHeadModeSetting* mode_setting)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_SET_HEAD_MODE_SETTING, mode_setting);
+}
+
+ALWAYS_INLINE int graphics_connector_set_safe_head_mode_setting(int fd)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_SET_SAFE_HEAD_MODE_SETTING, nullptr);
+}
+
+ALWAYS_INLINE int graphics_connector_get_head_mode_setting(int fd, GraphicsHeadModeSetting* mode_setting)
+{
+    GraphicsHeadModeSetting head_mode_setting;
+    if (auto rc = ioctl(fd, GRAPHICS_IOCTL_GET_HEAD_MODE_SETTING, &head_mode_setting); rc < 0)
+        return rc;
+    mode_setting->horizontal_stride = head_mode_setting.horizontal_stride;
+    mode_setting->pixel_clock_in_khz = head_mode_setting.pixel_clock_in_khz;
+    mode_setting->horizontal_active = head_mode_setting.horizontal_active;
+    mode_setting->horizontal_front_porch_pixels = head_mode_setting.horizontal_front_porch_pixels;
+    mode_setting->horizontal_sync_time_pixels = head_mode_setting.horizontal_sync_time_pixels;
+    mode_setting->horizontal_blank_pixels = head_mode_setting.horizontal_blank_pixels;
+    mode_setting->vertical_active = head_mode_setting.vertical_active;
+    mode_setting->vertical_front_porch_lines = head_mode_setting.vertical_front_porch_lines;
+    mode_setting->vertical_sync_time_lines = head_mode_setting.vertical_sync_time_lines;
+    mode_setting->vertical_blank_lines = head_mode_setting.vertical_blank_lines;
+    mode_setting->horizontal_offset = head_mode_setting.horizontal_offset;
+    mode_setting->vertical_offset = head_mode_setting.vertical_offset;
+    return 0;
+}
+
+ALWAYS_INLINE int fb_flush_buffers(int fd, int index, FBRect const* rects, unsigned count)
+{
+    FBFlushRects fb_flush_rects;
+    fb_flush_rects.buffer_index = index;
+    fb_flush_rects.count = count;
+    fb_flush_rects.rects = rects;
+    return ioctl(fd, GRAPHICS_IOCTL_FLUSH_HEAD_BUFFERS, &fb_flush_rects);
+}
+
+ALWAYS_INLINE int fb_flush_head(int fd)
+{
+    return ioctl(fd, GRAPHICS_IOCTL_FLUSH_HEAD, nullptr);
+}
+
+__END_DECLS