path: root/gamma-quartz-cg.c

/* See LICENSE file for copyright and license details. */
#ifndef HAVE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
# error Compiling gamma-quartz-cg.c without HAVE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
#endif

#include "gamma-quartz-cg.h"

#include "libgamma-error.h"

#ifdef FAKE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
# include "fake-quartz-cg.h"
#else
# include <ApplicationServices/ApplicationServices.h>
# include <CoreGraphics/CGDirectDisplay.h>
# define close_fake_quartz_cg() /* For compatibility with "fake-quartz-cg.h" */
#endif

#include <stdlib.h>
#include <errno.h>


/**
 * Return the capabilities of the adjustment method
 * 
 * @param  this  The data structure to fill with the method's capabilities
 */
void
libgamma_quartz_cg_method_capabilities(libgamma_method_capabilities_t* restrict this)
{
	/* Gamma ramps size and depth can be queried */
	this->crtc_information = LIBGAMMA_CRTC_INFO_GAMMA_SIZE | LIBGAMMA_CRTC_INFO_GAMMA_DEPTH;
	/* Quartz/CoreGraphics does not support sites or partitions */
	this->default_site_known = 1;
	this->multiple_sites = 0;
	this->multiple_partitions = 0;
	/* Quartz/CoreGraphics does support CRTC:s */
	this->multiple_crtcs = 1;
	/* Partitions are not supported... */
	this->partitions_are_graphics_cards = 0;
	/* CoreGraphics have support for system restore */
	this->site_restore = 1;
	this->partition_restore = 1;
	/* But not for individual CRTC:s */
	this->crtc_restore = 0;
	/* Gamma ramp sizes are identifical but not fixed */
	this->identical_gamma_sizes = 1;
	this->fixed_gamma_size = 0;
	/* Gamma ramp depths are fixed */
	this->fixed_gamma_depth = 1;
	/* Quartz/CoreGraphics is a real adjustment method that can be faked */
#ifdef FAKE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
	/* It is considered real but fake if it is translated to X RandR */
	this->fake = 1;
# ifdef HAVE_LIBGAMMA_METHOD_X_RANDR
	this->real = 1;
# else
	this->real = 0;
# endif
#else
	/* It is real and not fake if we are running on Mac OS X */
	this->fake = 0;
	this->real = 1;
#endif
	/* Gamma ramp adjustments are non-persistent */
	this->auto_restore = 1;
}


/**
 * Initialise an allocated site state
 * 
 * @param   this    The site state to initialise
 * @param   site    The site identifier, unless it is `NULL` it must a
 *                  `free`:able. Once the state is destroyed the library
 *                  will attempt to free it. There you should not free
 *                  it yourself, and it must not be a string constant
 *                  or allocate on the stack. Note however that it will
 *                  not be free:d if this function fails.
 * @return          Zero on success, otherwise (negative) the value of an
 *                  error identifier provided by this library
 */
int
libgamma_quartz_cg_site_initialise(libgamma_site_state_t *restrict this, char *restrict site)
{
	this->partitions_available = 1;
	return site ? 0 : LIBGAMMA_NO_SUCH_SITE;
}


/**
 * Release all resources held by a site state
 * 
 * @param  this  The site state
 */
void
libgamma_quartz_cg_site_destroy(libgamma_site_state_t *restrict this)
{
	(void) this;
	close_fake_quartz_cg();
}


/**
 * Restore the gamma ramps all CRTC:s with a site to the system settings
 * 
 * @param   this  The site state
 * @return        Zero on success, otherwise (negative) the value of an
 *                error identifier provided by this library
 */
int
libgamma_quartz_cg_site_restore(libgamma_site_state_t *restrict this)
{
	(void) this;
	CGDisplayRestoreColorSyncSettings();
	return 0;
}



/**
 * Initialise an allocated partition state
 * 
 * @param   this       The partition state to initialise
 * @param   site       The site state for the site that the partition belongs to
 * @param   partition  The the index of the partition within the site
 * @return             Zero on success, otherwise (negative) the value of an
 *                     error identifier provided by this library
 */
int
libgamma_quartz_cg_partition_initialise(libgamma_partition_state_t *restrict this,
                                       libgamma_site_state_t *restrict site, size_t partition)
{
	CGDirectDisplayID *crtcs, *crtcs_old;
	uint32_t cap = 4, n;

	(void) site;

	this->data = NULL;

	if (partition)
		return LIBGAMMA_NO_SUCH_PARTITION;

	/* Allocate array of CRTC ID:s */
	crtcs = malloc((size_t)cap * sizeof(CGDirectDisplayID));
	if (!crtcs)
		return LIBGAMMA_ERRNO_SET;

	/* It is not possible to ask CoreGraphics how many CRTC:s are
	 * available. We have to ask it to give us a ID:s of a number
	 * of CRTC:s and ask for more if we got as many as we asked for. */
	for (;;) {
		/* Ask for CRTC ID:s */
		if (CGGetOnlineDisplayList(cap, crtcs, &n) != kCGErrorSuccess)
			return free(crtcs), LIBGAMMA_LIST_CRTCS_FAILED;
		/* If we did not get as many as we asked for then we have all */
		if (n < cap)
			break;
		/* Increase the number CRTC ID:s to ask for */
		if (cap > SIZE_MAX / 2) /* We could also test ~0, but it is still too many */
			return free(crtcs), LIBGAMMA_IMPOSSIBLE_AMOUNT;
		cap <<= 1;
		/* Grow the array of CRTC ID:s so that it can fit all we are asking for */
		crtcs = realloc(crtcs_old = crtcs, (size_t)cap * sizeof(CGDirectDisplayID));
		if (!crtcs) {
			free(crtcs_old);
			return LIBGAMMA_ERRNO_SET;
		}
	}

	/* Store CRTC ID:s and CRTC count */
	this->data = crtcs;
	this->crtcs_available = (size_t)n;
	return 0;
}


/**
 * Release all resources held by a partition state
 * 
 * @param  this  The partition state
 */
void
libgamma_quartz_cg_partition_destroy(libgamma_partition_state_t *restrict this)
{
	free(this->data);
}


/**
 * Restore the gamma ramps all CRTC:s with a partition to the system settings
 * 
 * @param   this  The partition state
 * @return        Zero on success, otherwise (negative) the value of an
 *                error identifier provided by this library
 */
int
libgamma_quartz_cg_partition_restore(libgamma_partition_state_t *restrict this)
{
	return libgamma_quartz_cg_site_restore(this->site);
}



/**
 * Initialise an allocated CRTC state
 * 
 * @param   this       The CRTC state to initialise
 * @param   partition  The partition state for the partition that the CRTC belongs to
 * @param   crtc       The the index of the CRTC within the site
 * @return             Zero on success, otherwise (negative) the value of an
 *                     error identifier provided by this library
 */
int
libgamma_quartz_cg_crtc_initialise(libgamma_crtc_state_t *restrict this,
                                   libgamma_partition_state_t *restrict partition, size_t crtc)
{
	(void) this;
	return crtc < partition->crtcs_available ? 0 : LIBGAMMA_NO_SUCH_CRTC;
}


/**
 * Release all resources held by a CRTC state
 * 
 * @param  this  The CRTC state
 */
void
libgamma_quartz_cg_crtc_destroy(libgamma_crtc_state_t *restrict this)
{
	(void) this;
}


/**
 * Restore the gamma ramps for a CRTC to the system settings for that CRTC
 * 
 * @param   this  The CRTC state
 * @return        Zero on success, otherwise (negative) the value of an
 *                error identifier provided by this library
 */
int
libgamma_quartz_cg_crtc_restore(libgamma_crtc_state_t *restrict this)
{
	(void) this;
	errno = ENOTSUP;
	return LIBGAMMA_ERRNO_SET;
}



/**
 * Read information about a CRTC
 * 
 * @param   this    Instance of a data structure to fill with the information about the CRTC
 * @param   crtc    The state of the CRTC whose information should be read
 * @param   fields  OR:ed identifiers for the information about the CRTC that should be read.
 * @return          Zero on success, -1 on error. On error refer to the error reports in `this`
 */
int
libgamma_quartz_cg_get_crtc_information(libgamma_crtc_information_t *restrict this,
                                        libgamma_crtc_state_t *restrict crtc, int32_t fields)
{
#define SUPPORTED_FIELDS (LIBGAMMA_CRTC_INFO_GAMMA_SIZE | LIBGAMMA_CRTC_INFO_GAMMA_DEPTH)
#define _E(FIELD)        ((fields & FIELD) ? LIBGAMMA_CRTC_INFO_NOT_SUPPORTED : 0)

	CGDirectDisplayID *restrict crtcs;
	size_t gamma_size;

	/* Quartz/CoreGraphics does not support EDID or monitor dimensions */
	this->edid_error = _E(LIBGAMMA_CRTC_INFO_EDID);
	this->width_mm_error = _E(LIBGAMMA_CRTC_INFO_WIDTH_MM);
	this->height_mm_error = _E(LIBGAMMA_CRTC_INFO_HEIGHT_MM);
	this->width_mm_edid_error = _E(LIBGAMMA_CRTC_INFO_WIDTH_MM_EDID);
	this->height_mm_edid_error = _E(LIBGAMMA_CRTC_INFO_HEIGHT_MM_EDID);
	/* Quartz/CoreGraphics does support gamma ramp size query
	   The gamma ramps are identical but not fixed, and the query can fail */
	this->gamma_size_error = 0;
	if ((fields & LIBGAMMA_CRTC_INFO_GAMMA_SIZE)) {
		crtcs = crtc->partition->data;
		gamma_size = CGDisplayGammaTableCapacity(crtcs[crtc->crtc]);
		this->red_gamma_size = this->green_gamma_size = this->blue_gamma_size = (size_t)gamma_size;
		this->gamma_size_error = gamma_size < 2 ? LIBGAMMA_SINGLETON_GAMMA_RAMP : 0;
	}
	/* Quartz/CoreGraphics uses `float` ramps */
	this->gamma_depth = -1;
	this->gamma_depth_error = 0;
	/* Quartz/CoreGraphics does not support gamma ramp support queries */
	this->gamma_support_error = _E(LIBGAMMA_CRTC_INFO_GAMMA_SUPPORT);
	/* Quartz/CoreGraphics does not support EDID or connector information */
	this->subpixel_order_error = _E(LIBGAMMA_CRTC_INFO_SUBPIXEL_ORDER);
	this->active_error = _E(LIBGAMMA_CRTC_INFO_ACTIVE);
	this->connector_name_error = _E(LIBGAMMA_CRTC_INFO_CONNECTOR_NAME);
	this->connector_type_error = _E(LIBGAMMA_CRTC_INFO_CONNECTOR_TYPE);
	this->gamma_error = _E(LIBGAMMA_CRTC_INFO_GAMMA);

	/* We failed if gamma ramp size query failed or if an unsupport field was queried */
	return (this->gamma_size_error || (fields & ~SUPPORTED_FIELDS)) ? -1 : 0;

#undef _E
#undef SUPPORTED_FIELDS
}


/**
 * Get the current gamma ramps for a CRTC, `float` version
 * 
 * @param   this   The CRTC state
 * @param   ramps  The gamma ramps to fill with the current values
 * @return         Zero on success, otherwise (negative) the value of an
 *                 error identifier provided by this library
 */
int
libgamma_quartz_cg_crtc_get_gamma_rampsf(libgamma_crtc_state_t *restrict this, libgamma_gamma_rampsf_t *restrict ramps)
{
	CGDirectDisplayID *restrict crtcs = this->partition->data;
	CGDirectDisplayID crtc_id = crtcs[this->crtc];
	uint32_t gamma_size_out;
	CGError r;
#ifdef DEBUG
	/* Gamma ramps sizes are identical but not fixed */
	if (ramps->red_size != ramps->green_size || ramps->red_size != ramps->blue_size)
		return LIBGAMMA_MIXED_GAMMA_RAMP_SIZE;
#endif
	/* Read current gamma ramps */
	r = CGGetDisplayTransferByTable(crtc_id, (uint32_t)ramps->red_size, ramps->red, ramps->green, ramps->blue, &gamma_size_out);
	if (r != kCGErrorSuccess)
		return LIBGAMMA_GAMMA_RAMP_READ_FAILED;
	/* I hope that it will not actually ever change,
	   but it does return the the gamma ramp size despite
	   that it can be queried without querying for more */
	if (gamma_size_out != ramps->red_size)
		return LIBGAMMA_GAMMA_RAMP_SIZE_CHANGED;
	return 0;
}


/**
 * Set the gamma ramps for a CRTC, `float` version
 * 
 * @param   this   The CRTC state
 * @param   ramps  The gamma ramps to apply
 * @return         Zero on success, otherwise (negative) the value of an
 *                 error identifier provided by this library
 */
int
libgamma_quartz_cg_crtc_set_gamma_rampsf(libgamma_crtc_state_t *restrict this, libgamma_gamma_rampsf_t ramps)
{
	CGDirectDisplayID *restrict crtcs = this->partition->data;
	CGDirectDisplayID crtc_id = crtcs[this->crtc];
	CGError r;
#ifdef DEBUG
	/* Gamma ramps sizes are identical but not fixed */
	if (ramps.red_size != ramps.green_size || ramps.red_size != ramps.blue_size)
		return LIBGAMMA_MIXED_GAMMA_RAMP_SIZE;
#endif
	/* Apply gamma ramps */
	r = CGSetDisplayTransferByTable(crtc_id, (uint32_t)ramps.red_size, ramps.red, ramps.green, ramps.blue);
	return r == kCGErrorSuccess ? 0 : LIBGAMMA_GAMMA_RAMP_WRITE_FAILED;
}