/* See LICENSE file for copyright and license details. */
#include <sys/ioctl.h>
#include <linux/fb.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <fcntl.h>
#include <math.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include <xf86drm.h>
#include <xf86drmMode.h>
/**
* Framebuffer information
*/
typedef struct framebuffer
{
/**
* The file descriptor used to access the framebuffer, -1 if not opened
*/
int fd;
/**
* The width of the display in pixels
*/
uint32_t width;
/**
* The height of the display in pixels
*/
uint32_t height;
/**
* Increment for `mem` to move to next pixel on the line
*/
uint32_t bytes_per_pixel;
/**
* Increment for `mem` to move down one line but stay in the same column
*/
uint32_t line_length;
/**
* Framebuffer pointer, `MAP_FAILED` (from <sys/mman.h>) if not mapped
*/
int8_t *mem;
} framebuffer_t;
/**
* Graphics card information
*/
typedef struct drm_card
{
/**
* File descriptor for the connection to the graphics card,
* -1 if not opened
*/
int fd;
/**
* The graphics card's mode resources, `NULL` if not acquired
*/
drmModeRes *restrict res;
/**
* The number of CRTC:s available on the graphics card
*/
size_t crtc_count;
/**
* The available connectors
*/
drmModeConnector **restrict connectors;
/**
* The available encoders
*/
drmModeEncoder **restrict encoders;
/**
* The number of connectors and encoders
*/
size_t connector_count;
} drm_card_t;
/**
* CRT controller information
*/
typedef struct drm_crtc
{
/**
* CRT controller identifier
*/
uint32_t id;
/**
* The graphics card
*/
drm_card_t *restrict card;
/**
* The CRT controller's connector
*/
drmModeConnector *restrict connector;
/**
* The CRT controller's encoder
*/
drmModeEncoder *restrict encoder;
/**
* Whether the connector is connected
*/
int connected;
/**
* The CRT's EDID, hexadecimally encoded
*/
char *restrict edid;
/**
* The number of stops on the gamma ramps
*/
size_t gamma_stops;
/**
* The gamma ramp for the red channel
*/
uint16_t *restrict red;
/**
* The gamma ramp for the green channel
*/
uint16_t *restrict green;
/**
* The gamma ramp for the blue channel
*/
uint16_t *restrict blue;
} drm_crtc_t;
/***** gamma.c *****/
/**
* Analyse a gamma ramp
*
* @param stops The number of stops in the gamma ramp
* @param ramp The gamma ramp
* @param gamma Output parameter for the gamma
* @param contrast Output parameter for the contrast
* @param brightness Output parameter for the brightness
*/
void gamma_analyse(size_t stops, const uint16_t* restrict ramp, double *restrict gamma,
double *restrict contrast, double* restrict brightness);
/**
* Generate a gamma ramp
*
* @param stops The number of stops in the gamma ramp
* @param ramp Memory area to where to write the gamma ramp
* @param gamma The gamma
* @param contrast The contrast
* @param brightness The brightness
*/
void gamma_generate(size_t stops, uint16_t *restrict ramp, double gamma, double contrast, double brightness);
/***** framebuffer.c *****/
/**
* Figure out how many framebuffers there are on the system
*
* @return The number of framebuffers on the system
*/
size_t fb_count(void);
/**
* Open a framebuffer
*
* @param index The index of the framebuffer to open
* @param fb Framebuffer information to fill in
* @return Zero on success, -1 on error
*/
int fb_open(size_t index, framebuffer_t *restrict fb);
/**
* Close a framebuffer
*
* @param fb The framebuffer information
*/
void fb_close(framebuffer_t *restrict fb);
/**
* Construct an sRGB colour in 32-bit XRGB encoding to
* use when specifying colours
*
* @param red The red component from [0, 255] sRGB
* @param green The green component from [0, 255] sRGB
* @param blue The blue component from [0, 255] sRGB
* @return The colour as one 32-bit integer
*/
#ifdef __GNUC__
__attribute__((__const__))
#endif
uint32_t fb_colour(int red, int green, int blue);
/**
* Print a filled in rectangle to a framebuffer
*
* @param fb The framebuffer
* @param colour The colour to use when drawing the rectangle
* @param x The starting pixel on the X axis for the rectangle
* @param y The starting pixel on the Y axis for the rectangle
* @param width The width of the rectangle, in pixels
* @param height The height of the rectangle, in pixels
*/
void fb_fill_rectangle(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y, uint32_t width, uint32_t height);
/**
* Draw a horizontal line segment on a framebuffer
*
* @param fb The framebuffer
* @param colour The colour to use when drawing the rectangle
* @param x The starting pixel on the X axis for the line segment
* @param y The starting pixel on the Y axis for the line segment
* @param length The length of the line segment, in pixels
*/
void fb_draw_horizontal_line(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y, uint32_t length);
/**
* Draw a vertical line segment on a framebuffer
*
* @param fb The framebuffer
* @param colour The colour to use when drawing the rectangle
* @param x The starting pixel on the X axis for the line segment
* @param y The starting pixel on the Y axis for the line segment
* @param length The length of the line segment, in pixels
*/
void fb_draw_vertical_line(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y, uint32_t length);
/**
* Draw a single on a framebuffer
*
* @param fb The framebuffer
* @param colour The colour to use when drawing the rectangle
* @param x The pixel's position on the X axis
* @param y The pixel's position on the Y axis
*/
static inline void
fb_draw_pixel(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y)
{
int8_t *mem = fb->mem + y * fb->line_length + x * fb->bytes_per_pixel;
*(uint32_t *)mem = colour;
}
/***** state.c ******/
/**
* The framebuffers on the system
*/
extern framebuffer_t *restrict framebuffers;
/**
* The number of elements in `framebuffers`
*/
extern size_t framebuffer_count;
/**
* The graphics cards on the system
*/
extern drm_card_t *restrict cards;
/**
* The number of elements in `cards`
*/
extern size_t card_count;
/**
* The connected CRT controllers on the system
*/
extern drm_crtc_t *restrict crtcs;
/**
* The software brightness setting on each connected CRT controller, on each channel
*/
extern double *restrict brightnesses[3];
/**
* The software contrast setting on each connected CRT controller, on each channel
*/
extern double *restrict contrasts[3];
/**
* The gamma correction on each connected CRT controller, on each channel
*/
extern double *restrict gammas[3];
/**
* The number of elements in `crtcs`, `brightnesses[]`, `contrasts[]` and `gammas[]`
*/
extern size_t crtc_count;
/**
* Acquire video control
*
* @return Zero on success, -1 on error
*/
int acquire_video(void);
/**
* Release video control
*/
void release_video(void);
/***** drmgamma.c ******/
/**
* Figure out how many graphics cards there are on the system
*
* @return The number of graphics cards on the system
*/
size_t drm_card_count(void);
/**
* Acquire access to a graphics card
*
* @param index The index of the graphics card
* @param card Graphics card information to fill in
* @return Zero on success, -1 on error
*/
int drm_card_open(size_t index, drm_card_t *restrict card);
/**
* Release access to a graphics card
*
* @param card The graphics card information
*/
void drm_card_close(drm_card_t *restrict card);
/**
* Acquire access to a CRT controller
*
* @param index The index of the CRT controller
* @param card The graphics card information
* @param crtc CRT controller information to fill in
* @return Zero on success, -1 on error
*/
int drm_crtc_open(size_t index, drm_card_t *restrict card, drm_crtc_t *restrict crtc);
/**
* Release access to a CRT controller
*
* @param crtc The CRT controller information to fill in
*/
void drm_crtc_close(drm_crtc_t *restrict crtc);
/**
* Read the gamma ramps for a CRT controller
*
* @param crtc CRT controller information
* @return Zero on success, -1 on error
*/
int drm_get_gamma(drm_crtc_t *restrict crtc);
/**
* Apply gamma ramps for a CRT controller
*
* @param crtc CRT controller information
* @return Zero on success, -1 on error
*/
int drm_set_gamma(drm_crtc_t *restrict crtc);
