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-rw-r--r--gamma-x-randr.c985
1 files changed, 985 insertions, 0 deletions
diff --git a/gamma-x-randr.c b/gamma-x-randr.c
new file mode 100644
index 0000000..95d730c
--- /dev/null
+++ b/gamma-x-randr.c
@@ -0,0 +1,985 @@
+/* See LICENSE file for copyright and license details. */
+#ifndef HAVE_LIBGAMMA_METHOD_X_RANDR
+# error Compiling gamma-x-randr.c without HAVE_LIBGAMMA_METHOD_X_RANDR
+#endif
+
+#include "gamma-x-randr.h"
+
+#include "libgamma-error.h"
+#include "edid.h"
+
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <stdint.h>
+#ifdef DEBUG
+# include <stdio.h>
+#endif
+
+#include <xcb/xcb.h>
+#include <xcb/randr.h>
+
+
+/**
+ * The major version of RandR the library expects
+ */
+#define RANDR_VERSION_MAJOR 1
+
+/**
+ * The minor version of RandR the library expects
+ */
+#define RANDR_VERSION_MINOR 3
+
+
+
+/**
+ * Data structure for partition data
+ */
+typedef struct libgamma_x_randr_partition_data {
+ /**
+ * Mapping from CRTC indices to CRTC identifiers
+ */
+ xcb_randr_crtc_t *crtcs;
+
+ /**
+ * Mapping from output indices to output identifiers
+ */
+ xcb_randr_output_t *outputs;
+
+ /**
+ * The number of outputs available
+ */
+ size_t outputs_count;
+
+ /**
+ * Mapping from CRTC indices to output indices.
+ * CRTC's without an output (should be impossible)
+ * have the value `SIZE_MAX` which is impossible
+ * for an existing mapping
+ */
+ size_t *crtc_to_output;
+
+ /**
+ * Screen configuration timestamp
+ */
+ xcb_timestamp_t config_timestamp;
+
+} libgamma_x_randr_partition_data_t;
+
+
+
+/**
+ * Translate an xcb error into a libgamma error
+ *
+ * @param error_code The xcb error
+ * @param default_error The libgamma error to use if the xcb error is not recognised
+ * @return The libgamma error
+ */
+static int
+translate_error_(int error_code, int default_error)
+{
+ switch (error_code) {
+ case XCB_CONN_ERROR: return errno = ECONNABORTED, LIBGAMMA_ERRNO_SET;
+ case XCB_CONN_CLOSED_EXT_NOTSUPPORTED: return errno = ENOPROTOOPT, LIBGAMMA_ERRNO_SET;
+ case XCB_CONN_CLOSED_MEM_INSUFFICIENT: return errno = ENOMEM, LIBGAMMA_ERRNO_SET;
+ case XCB_CONN_CLOSED_REQ_LEN_EXCEED: return errno = EMSGSIZE, LIBGAMMA_ERRNO_SET;
+ case XCB_CONN_CLOSED_PARSE_ERR: return LIBGAMMA_NO_SUCH_SITE;
+ case XCB_CONN_CLOSED_INVALID_SCREEN: return LIBGAMMA_NO_SUCH_PARTITION;
+ case XCB_CONN_CLOSED_FDPASSING_FAILED: return errno = EIO, LIBGAMMA_ERRNO_SET;
+ default:
+ return default_error;
+ }
+}
+
+
+/**
+ * Translate an xcb error into a libgamma error
+ *
+ * @param error_code The xcb error
+ * @param default_error The libgamma error to use if the xcb error is not recognised
+ * @param return_errno Whether an `errno` value may be returned
+ * @return The libgamma error
+ */
+static int
+translate_error(int error_code, int default_error, int return_errno)
+{
+ int r = translate_error_(error_code, default_error);
+ return (return_errno && r > 0) ? errno : r;
+}
+
+
+/**
+ * Return the capabilities of the adjustment method
+ *
+ * @param this The data structure to fill with the method's capabilities
+ */
+void
+libgamma_x_randr_method_capabilities(libgamma_method_capabilities_t *restrict this)
+{
+ char *display = getenv("DISPLAY");
+ /* Support for all information except active status and gamma ramp support.
+ Active status can be queried but it is not guaranteed produces an up to date result. */
+ this->crtc_information = LIBGAMMA_CRTC_INFO_MACRO_EDID
+ | LIBGAMMA_CRTC_INFO_MACRO_VIEWPORT
+ | LIBGAMMA_CRTC_INFO_MACRO_RAMP
+ | LIBGAMMA_CRTC_INFO_SUBPIXEL_ORDER
+ | LIBGAMMA_CRTC_INFO_MACRO_CONNECTOR;
+ /* X RandR supports multiple sites, partitions and CRTC:s */
+ this->default_site_known = display && *display;
+ this->multiple_sites = 1;
+ this->multiple_partitions = 1;
+ this->multiple_crtcs = 1;
+ /* Partitions are screens and not graphics cards in X */
+ this->partitions_are_graphics_cards = 0;
+ /* X does not have system restore capabilities */
+ this->site_restore = 0;
+ this->partition_restore = 0;
+ this->crtc_restore = 0;
+ /* Gamma ramp sizes are identical but not fixed */
+ this->identical_gamma_sizes = 1;
+ this->fixed_gamma_size = 0;
+ /* Gamma ramp depths are fixed */
+ this->fixed_gamma_depth = 1;
+ /* X RandR is a real non-faked adjustment method */
+ this->real = 1;
+ this->fake = 0;
+ /* Gamma ramp adjustments are persistent */
+ this->auto_restore = 0;
+}
+
+
+/* xcb violates the rule to never return struct:s */
+#ifdef __GNUC__
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Waggregate-return"
+#endif
+
+
+/**
+ * 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_x_randr_site_initialise(libgamma_site_state_t *restrict this, char *restrict site)
+{
+ xcb_generic_error_t *error = NULL;
+ xcb_connection_t *restrict connection;
+ xcb_randr_query_version_cookie_t cookie;
+ xcb_randr_query_version_reply_t *restrict reply;
+ const xcb_setup_t *restrict setup;
+ xcb_screen_iterator_t iter;
+
+ /* Connect to the display server */
+ this->data = connection = xcb_connect(site, NULL);
+ if (!connection || xcb_connection_has_error(connection))
+ return LIBGAMMA_OPEN_SITE_FAILED;
+
+ /* Query the version of the X RandR extension protocol */
+ cookie = xcb_randr_query_version(connection, RANDR_VERSION_MAJOR, RANDR_VERSION_MINOR);
+ reply = xcb_randr_query_version_reply(connection, cookie, &error);
+
+ /* Check for version query failure */
+ if (error || !reply) {
+ /* Release resources */
+ free(reply);
+ /* If `xcb_connect` failed, both `error` and `reply` will be `NULL`.
+ * TODO: Can both be `NULL` for any other reason? */
+ if (!error && !reply)
+ return LIBGAMMA_OPEN_SITE_FAILED;
+ xcb_disconnect(connection);
+ /* Translate and report error. */
+ if (error != NULL)
+ return translate_error(error->error_code, LIBGAMMA_PROTOCOL_VERSION_QUERY_FAILED, 0);
+ return LIBGAMMA_PROTOCOL_VERSION_QUERY_FAILED;
+ }
+
+ /* Check protocol compatibility,
+ we require 1.3 but 2.x may not be backwards compatible */
+ if (reply->major_version != RANDR_VERSION_MAJOR || reply->minor_version < RANDR_VERSION_MINOR) {
+#ifdef DEBUG
+ /* Print used protocol */
+ fprintf(stderr, "libgamma: RandR protocol version: %u.%u", reply->major_version, reply->minor_version);
+#endif
+ /* Release resources */
+ free(reply);
+ xcb_disconnect(connection);
+ /* Report error */
+ return LIBGAMMA_PROTOCOL_VERSION_NOT_SUPPORTED;
+ }
+
+ /* We do not longer need to know the version of the protocol */
+ free(reply);
+
+ /* Get available screens */
+ setup = xcb_get_setup(connection);
+ if (!setup) {
+ xcb_disconnect(connection);
+ return LIBGAMMA_LIST_PARTITIONS_FAILED;
+ }
+ iter = xcb_setup_roots_iterator(setup);
+ /* Get the number of available screens */
+ this->partitions_available = (size_t)iter.rem;
+
+ /* Sanity check the number of available screens. */
+ return iter.rem >= ? 0 : LIBGAMMA_NEGATIVE_PARTITION_COUNT;
+}
+
+
+/**
+ * Release all resources held by a site state
+ *
+ * @param this The site state
+ */
+void
+libgamma_x_randr_site_destroy(libgamma_site_state_t *restrict this)
+{
+ xcb_disconnect((xcb_connection_t *)this->data);
+}
+
+
+/**
+ * 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_x_randr_site_restore(libgamma_site_state_t *restrict this)
+{
+ (void) this;
+ errno = ENOTSUP;
+ return LIBGAMMA_ERRNO_SET;
+}
+
+
+/**
+ * Duplicate a memory area
+ *
+ * @param ptr The memory area
+ * @param bytes The size, in bytes, of the memory area
+ * @return A duplication of the memory, `NULL` if zero-length or on error
+ */
+static inline void *
+memdup(void *restrict ptr, size_t bytes)
+{
+ char *restrict rc;
+ if (!bytes)
+ return NULL;
+ rc = malloc(bytes);
+ if (!rc)
+ return NULL;
+ memcpy(rc, ptr, bytes);
+ return rc;
+}
+
+
+/**
+ * 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_x_randr_partition_initialise(libgamma_partition_state_t *restrict this,
+ libgamma_site_state_t *restrict site, size_t partition)
+{
+ int fail_rc = LIBGAMMA_ERRNO_SET;
+ xcb_connection_t *restrict connection = site->data;
+ xcb_screen_t *restrict screen = NULL;
+ xcb_generic_error_t *error = NULL;
+ const xcb_setup_t *restrict setup;
+ xcb_screen_iterator_t iter;
+ xcb_randr_get_screen_resources_current_cookie_t cookie;
+ xcb_randr_get_screen_resources_current_reply_t *restrict reply;
+ xcb_randr_crtc_t *restrict crtcs;
+ xcb_randr_output_t *restrict outputs;
+ libgamma_x_randr_partition_data_t *restrict data;
+ xcb_randr_get_output_info_cookie_t out_cookie;
+ xcb_randr_get_output_info_reply_t *out_reply;
+ size_t i;
+ uint16_t j;
+
+ /* Get screen list */
+ setup = xcb_get_setup(connection);
+ if (!setup)
+ return LIBGAMMA_LIST_PARTITIONS_FAILED;
+ iter = xcb_setup_roots_iterator(setup);
+
+ /* Get the screen */
+ for (i = 0; iter.rem > 0; i++, xcb_screen_next(&iter))
+ if (i == partition) {
+ screen = iter.data;
+ break;
+ }
+ /* Report failure if we did not find the screen */
+ if (!iter.rem)
+ return LIBGAMMA_NO_SUCH_PARTITION;
+
+ /* Check that the screen is not `NULL`.
+ * (Do not think this can happen, but why not.) */
+ if (!screen)
+ return LIBGAMMA_NULL_PARTITION;
+
+ /* Get the current resources of the screen */
+ cookie = xcb_randr_get_screen_resources_current(connection, screen->root);
+ reply = xcb_randr_get_screen_resources_current_reply(connection, cookie, &error);
+ if (error)
+ return translate_error(error->error_code, LIBGAMMA_LIST_CRTCS_FAILED, 0);
+
+ /* Get the number of available CRTC:s */
+ this->crtcs_available = reply->num_crtcs;
+ /* Get the CRTC and output lists */
+ crtcs = xcb_randr_get_screen_resources_current_crtcs(reply);
+ outputs = xcb_randr_get_screen_resources_current_outputs(reply);
+ if (!crtcs || !outputs) {
+ free(reply);
+ return LIBGAMMA_REPLY_VALUE_EXTRACTION_FAILED;
+ }
+
+ /* Allocate adjustment method dependent data memory area.
+ We use `calloc` because we want `data`'s pointers to be `NULL` if not allocated at `fail`. */
+ data = calloc(1, sizeof(libgamma_x_randr_partition_data_t));
+ if (!data)
+ goto fail;
+
+ /* Copy the CRTC:s, just so we do not have to keep the reply in memory */
+ data->crtcs = memdup(crtcs, (size_t)(reply->num_crtcs) * sizeof(xcb_randr_crtc_t));
+ if (!data->crtcs && reply->num_crtcs > 0)
+ goto fail;
+
+ /* Copy the outputs as well */
+ data->outputs = memdup(outputs, (size_t)reply->num_outputs * sizeof(xcb_randr_output_t));
+ if (!data->outputs && reply->num_outputs > 0)
+ goto fail;
+
+ /* Get the number of available outputs */
+ data->outputs_count = (size_t)reply->num_outputs;
+
+ /* Create mapping table from CRTC indices to output indicies. (injection) */
+ data->crtc_to_output = malloc((size_t)reply->num_crtcs * sizeof(size_t));
+ if (!data->crtc)
+ goto fail;
+ /* All CRTC:s should be mapped, but incase they are not, all unmapped CRTC:s should have
+ an invalid target, namely `SIZE_MAX`, which is 1 more than the theoretical limit */
+ for (i = 0; i < (size_t)reply->num_crtcs; i++)
+ data->crtc_to_output[i] = SIZE_MAX;
+ /* Fill the table */
+ for (i = 0; i < (size_t)reply->num_outputs; i++) {
+ /* Query output (target) information */
+ out_cookie = xcb_randr_get_output_info(connection, outputs[i], reply->config_timestamp);
+ out_reply = xcb_randr_get_output_info_reply(connection, out_cookie, &error);
+ if (error) {
+ fail_rc = translate_error(error->error_code, LIBGAMMA_OUTPUT_INFORMATION_QUERY_FAILED, 0);
+ goto fail;
+ }
+
+ /* Find CRTC (source) */
+ for (j = 0; j < reply->num_crtcs; j++) {
+ if (crtcs[j] == out_reply->crtc) {
+ data->crtc_to_output[j] = i;
+ break;
+ }
+ }
+
+ /* Release output information */
+ free(out_reply);
+ }
+
+ /* Store the configuration timestamp */
+ data->config_timestamp = reply->config_timestamp;
+ /* Store the adjustment method dependent data */
+ this->data = data;
+ /* Release resources and return successfully */
+ free(reply);
+ return 0;
+
+fail:
+ /* Release resources and return with an error */
+ if (data) {
+ free(data->crtcs);
+ free(data->outputs);
+ free(data->crtc_to_output);
+ free(data);
+ }
+ free(reply);
+ return fail_rc;
+}
+
+
+/**
+ * Release all resources held by a partition state
+ *
+ * @param this The partition state
+ */
+void
+libgamma_x_randr_partition_destroy(libgamma_partition_state_t *restrict this)
+{
+ libgamma_x_randr_partition_data_t *restrict data = this->data;
+ free(data->crtcs);
+ free(data->outputs);
+ free(data->crtc_to_output);
+ free(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_x_randr_partition_restore(libgamma_partition_state_t *restrict this)
+{
+ (void) this;
+ errno = ENOTSUP;
+ return LIBGAMMA_ERRNO_SET;
+}
+
+
+
+/**
+ * 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_x_randr_crtc_initialise(libgamma_crtc_state_t *restrict this,
+ libgamma_partition_state_t *restrict partition, size_t crtc)
+{
+ libgamma_x_randr_partition_data_t *restrict screen_data = partition->data;
+ xcb_randr_crtc_t *restrict crtc_ids = screen_data->crtcs;
+ this->data = crtc_ids + crtc;
+ 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_x_randr_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_x_randr_crtc_restore(libgamma_crtc_state_t *restrict this)
+{
+ (void) this;
+ errno = ENOTSUP;
+ return LIBGAMMA_ERRNO_SET;
+}
+
+
+
+/**
+ * Get the gamma ramp size of 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
+ * @return Non-zero on error
+ */
+static int
+get_gamma_ramp_size(libgamma_crtc_information_t *restrict out, libgamma_crtc_state_t *restrict crtc)
+{
+ xcb_connection_t *restrict connection = crtc->partition->site->data;
+ xcb_randr_crtc_t *restrict crtc_id = crtc->data;
+ xcb_randr_get_crtc_gamma_size_cookie_t cookie;
+ xcb_randr_get_crtc_gamma_size_reply_t *restrict reply;
+ xcb_generic_error_t *error;
+
+ /* Query gamma ramp size */
+ out->gamma_size_error = 0;
+ cookie = xcb_randr_get_crtc_gamma_size(connection, *crtc_id);
+ reply = xcb_randr_get_crtc_gamma_size_reply(connection, cookie, &error);
+ if (error) {
+ out->gamma_size_error = translate_error(error->error_code, LIBGAMMA_GAMMA_RAMPS_SIZE_QUERY_FAILED, 1);
+ return out->gamma_size_error;
+ }
+ /* Sanity check gamma ramp size */
+ if (reply->size < 2)
+ out->gamma_size_error = LIBGAMMA_SINGLETON_GAMMA_RAMP;
+ /* Store gamma ramp size */
+ out->red_gamma_size = out->green_gamma_size = out->blue_gamma_size = reply->size;
+ /* Release resources and return successfulnes */
+ free(reply);
+ return out->gamma_size_error;
+}
+
+
+/**
+ * Read information from the CRTC's output
+ *
+ * @param out Instance of a data structure to fill with the information about the CRTC
+ * @param output The CRTC's output information
+ * @return Non-zero if at least on error occured
+ */
+static int
+read_output_data(libgamma_crtc_information_t *restrict out, xcb_randr_get_output_info_reply_t *restrict output)
+{
+#define __select(value)\
+ case XCB_RENDER_SUB_PIXEL_##value: out->subpixel_order = LIBGAMMA_SUBPIXEL_ORDER_##value; break
+
+ switch (output->connection) {
+ case XCB_RANDR_CONNECTION_CONNECTED:
+ /* We have a monitor connected, report that and store information that is provided to us */
+ out->active = 1;
+ out->width_mm = output->mm_width;
+ out->height_mm = output->mm_height;
+ switch (output->subpixel_order) {
+ __select (UNKNOWN);
+ __select (HORIZONTAL_RGB);
+ __select (HORIZONTAL_BGR);
+ __select (VERTICAL_RGB);
+ __select (VERTICAL_BGR);
+ __select (NONE);
+ default:
+ out->subpixel_order_error = LIBGAMMA_SUBPIXEL_ORDER_NOT_RECOGNISED;
+ break;
+ }
+ return 0;
+
+ case XCB_RANDR_CONNECTION_UNKNOWN:
+ /* If we do know whether a monitor is connected report that and assume it is not */
+ out->active_error = LIBGAMMA_STATE_UNKNOWN;
+ /* fall through */
+ default:
+ /* If no monitor is connected, report that on fails that require it */
+ out->width_mm_error = LIBGAMMA_NOT_CONNECTED;
+ out->height_mm_error = LIBGAMMA_NOT_CONNECTED;
+ out->subpixel_order_error = LIBGAMMA_NOT_CONNECTED;
+ /* And store that we are not connected */
+ out->active = 0;
+ /* This fuction only failed if we could not figure out whether a monitor is connected */
+ return output->connection != XCB_RANDR_CONNECTION_UNKNOWN ? 0 : -1;
+ }
+
+#undef __select
+}
+
+
+/**
+ * Determine the connector type from the connector name
+ *
+ * @param this The CRTC information to use and extend
+ * @param Non-zero on error
+ */
+static int
+get_connector_type(libgamma_crtc_information_t *restrict this)
+{
+ /* Since we require the name of the output of get the type of the connected,
+ copy any reported error on the output's name to the connector's type,
+ and report failure if there was an error */
+ if ((this->connector_type_error = this->connector_name_error))
+ return -1;
+
+#define __select(name, type)\
+ do {\
+ if (strstr(this->connector_name, name "-") == this->connector_name) {\
+ this->connector_type = LIBGAMMA_CONNECTOR_TYPE_##type\
+ return 0;\
+ }\
+ } while (0)
+
+ /* Check begin on the name of the output to find out what type the connector is of */
+ __select ("None", Unknown);
+ __select ("VGA", VGA);
+ __select ("DVI-I", DVII);
+ __select ("DVI-D", DVID);
+ __select ("DVI-A", DVIA);
+ __select ("DVI", DVI);
+ __select ("Composite", Composite);
+ __select ("S-Video", SVIDEO);
+ __select ("Component", Component);
+ __select ("LFP", LFP);
+ __select ("Proprietary", Unknown);
+ __select ("HDMI", HDMI);
+ __select ("DisplayPort", DisplayPort);
+
+#undef __select
+
+ /* If there was no matching output name pattern report that and exit with an error */
+ this->connector_name_error = LIBGAMMA_CONNECTOR_TYPE_NOT_RECOGNISED;
+ return -1;
+}
+
+
+/**
+ * Get the output name of a CRTC
+ *
+ * @param this Instance of a data structure to fill with the information about the CRTC
+ * @param output The CRTC's output's information
+ * @return Non-zero on error
+ */
+static int
+get_output_name(libgamma_crtc_information_t *restrict out, xcb_randr_get_output_info_reply_t *restrict output)
+{
+ char *restrict store;
+ uint8_t *restrict name;
+ uint16_t length;
+ size_t i;
+
+ /* Get the name of the output and the length of that name */
+ name = xcb_randr_get_output_info_name(output);
+ length = output->name_len; /* There is no NUL-termination */
+ if (!name)
+ return out->connector_name_error = LIBGAMMA_REPLY_VALUE_EXTRACTION_FAILED;
+
+ /* Allocate a memory area for a NUL-terminated copy of the name */
+ store = out->connector_name = malloc(((size_t)length + 1) * sizeof(char));
+ if (!store) {
+ out->connector_name_error = errno;
+ return -1;
+ }
+
+ /* char is guaranteed to be (u)int_least8_t, but it is only guaranteed to be (u)int8_t
+ * on POSIX, so to be truly portable we will not assume that char is (u)int8_t */
+ for (i = 0; i < (size_t)length; i++)
+ store[i] = (char)name[i];
+ store[length] = '\0';
+
+ return 0;
+}
+
+
+/**
+ * Get the Extended Display Information Data of the monitor connected to the connector of a CRTC
+ *
+ * @param out 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 output The CRTC's output
+ * @return Non-zero on error
+ */
+static int
+get_edid(libgamma_crtc_information_t *restrict out, libgamma_crtc_state_t *restrict crtc, xcb_randr_output_t output)
+{
+ xcb_connection_t *restrict connection = crtc->partition->site->data;
+ xcb_randr_list_output_properties_cookie_t prop_cookie;
+ xcb_randr_list_output_properties_reply_t *restrict prop_reply;
+ xcb_atom_t *atoms;
+ xcb_atom_t *atoms_end;
+ xcb_generic_error_t *error;
+ xcb_get_atom_name_cookie_t atom_name_cookie;
+ xcb_get_atom_name_reply_t *restrict atom_name_reply;
+ char *restrict atom_name;
+ int atom_name_len;
+ xcb_randr_get_output_property_cookie_t atom_cookie;
+ xcb_randr_get_output_property_reply_t *restrict atom_reply;
+ unsigned char* restrict atom_data;
+ int length;
+
+ /* Acquire a list of all properties of the output */
+ prop_cookie = xcb_randr_list_output_properties(connection, output);
+ prop_reply = xcb_randr_list_output_properties_reply(connection, prop_cookie, &error);
+ if (error)
+ return out->edid_error = translate_error(error->error_code, LIBGAMMA_LIST_PROPERTIES_FAILED, 1);
+
+ /* Extract the properties form the data structure that holds them, */
+ atoms = xcb_randr_list_output_properties_atoms(prop_reply);
+ /* and get the last one so that we can iterate over them nicely */
+ atoms_end = atoms + xcb_randr_list_output_properties_atoms_length(prop_reply);
+
+ if (!atoms) {
+ free(prop_reply);
+ return out->edid_error = LIBGAMMA_REPLY_VALUE_EXTRACTION_FAILED;
+ }
+
+ /* For each property */
+ for (; atoms != atoms_end; atoms++) {
+ /* Acquire the atom name */
+ atom_name_cookie = xcb_get_atom_name(connection, *atoms);
+ atom_name_reply = xcb_get_atom_name_reply(connection, atom_name_cookie, &error);
+ if (error)
+ continue;
+
+ /* Extract the atom name from the data structure that holds it */
+ atom_name = xcb_get_atom_name_name(atom_name_reply);
+ /* As well as the length of the name; it is not NUL-termianted */
+ atom_name_len = xcb_get_atom_name_name_length(atom_name_reply);
+
+ if (/* Check for errors */
+ !atom_name || /* atom_name_len < 1 || */
+ /* Check that the length is the expected length for the EDID property */
+ atom_name_len != 4 ||
+ /* Check that the property is the EDID property */
+ atom_name[0] != 'E' || atom_name[1] != 'D' || atom_name[2] != 'I' || atom_name[3] != 'D') {
+ free(atom_name_reply);
+ continue;
+ }
+
+ /* Acquire the property's value, we know that it is either 128 or 256 byte long */
+ atom_cookie = xcb_randr_get_output_property(connection, output, *atoms, XCB_GET_PROPERTY_TYPE_ANY, 0, 256, 0, 0);
+ atom_reply = xcb_randr_get_output_property_reply(connection, atom_cookie, &error);
+ /* (*) EDID version 1.0 through 1.4 define it as 128 bytes long,
+ * but version 2.0 define it as 256 bytes long. However,
+ * version 2.0 is rare(?) and has been deprecated and replaced
+ * by version 1.3 (I guess that is with a new version epoch,
+ * but I do not know.) */
+ if (error) {
+ free(atom_name_reply);
+ free(prop_reply);
+ return out->edid_error = LIBGAMMA_PROPERTY_VALUE_QUERY_FAILED;
+ }
+
+ /* Extract the property's value */
+ atom_data = xcb_randr_get_output_property_data(atom_reply);
+ /* and its actual length */
+ length = xcb_randr_get_output_property_data_length(atom_reply);
+ if (!atom_data || length < 1) {
+ free(atom_reply);
+ free(atom_name_reply);
+ free(prop_reply);
+ return out->edid_error = LIBGAMMA_REPLY_VALUE_EXTRACTION_FAILED;
+ }
+
+ /* Store the EDID */
+ out->edid_length = (size_t)length;
+ out->edid = malloc((size_t)length * sizeof(unsigned char));
+ if (!out->edid)
+ out->edid_error = errno;
+ else
+ memcpy(out->edid, atom_data, (size_t)length * sizeof(unsigned char));
+
+ /* Release resouces */
+ free(atom_reply);
+ free(atom_name_reply);
+ free(prop_reply);
+
+ return out->edid_error;
+ }
+
+ return out->edid_error = LIBGAMMA_EDID_NOT_FOUND;
+}
+
+
+/**
+ * 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_x_randr_get_crtc_information(libgamma_crtc_information_t *restrict this,
+ libgamma_crtc_state_t *restrict crtc, int32_t fields)
+{
+#define _E(FIELD) ((fields & FIELD) ? LIBGAMMA_CRTC_INFO_NOT_SUPPORTED : 0)
+
+ int e = 0;
+ xcb_randr_get_output_info_reply_t *restrict output_info = NULL;
+ xcb_randr_output_t output;
+ int free_edid, free_name;
+ xcb_connection_t *restrict connection;
+ libgamma_x_randr_partition_data_t *restrict screen_data;
+ size_t output_index;
+ xcb_randr_get_output_info_cookie_t cookie;
+ xcb_generic_error_t *error;
+
+ /* Wipe all error indicators */
+ memset(this, 0, sizeof(libgamma_crtc_information_t));
+
+ /* We need to free the EDID after us if it is not explicitly requested */
+ free_edid = !(fields & LIBGAMMA_CRTC_INFO_EDID);
+
+ /* We need to free the output's name after us if it is not explicitly requested */
+ free_name = !(fields & LIBGAMMA_CRTC_INFO_CONNECTOR_NAME);
+
+ /* Jump if the output information is not required */
+ if (!(fields & (LIBGAMMA_CRTC_INFO_MACRO_ACTIVE | LIBGAMMA_CRTC_INFO_MACRO_CONNECTOR)))
+ goto cont;
+
+ /* Get connector and connector information */
+ connection = crtc->partition->site->data;
+ screen_data = crtc->partition->data;
+ output_index = screen_data->crtc_to_output[crtc->crtc];
+ /* `SIZE_MAX` is used for CRTC:s that misses mapping to its output (should not happen),
+ * because `SIZE_MAX - 1` is the highest theoretical possible value */
+ if (output_index == SIZE_MAX) {
+ e |= this->edid_error = this->gamma_error = this->width_mm_edid_error
+ = this->height_mm_edid_error = this->connector_type_error
+ = this->connector_name_error = this->subpixel_order_error
+ = this->width_mm_error = this->height_mm_error
+ = this->active_error = LIBGAMMA_CONNECTOR_UNKNOWN;
+ goto cont;
+ }
+ /* Get the output */
+ output = screen_data->outputs[output_index];
+ /* Query output information */
+ cookie = xcb_randr_get_output_info(connection, output, screen_data->config_timestamp);
+ output_info = xcb_randr_get_output_info_reply(connection, cookie, &error);
+ if (error) {
+ e |= this->edid_error = this->gamma_error = this->width_mm_edid_error
+ = this->height_mm_edid_error = this->connector_type_error
+ = this->connector_name_error = this->subpixel_order_error
+ = this->width_mm_error = this->height_mm_error
+ = this->active_error = LIBGAMMA_OUTPUT_INFORMATION_QUERY_FAILED;
+ goto cont;
+ }
+
+ /* Get connector name */
+ e |= get_output_name(this, output_info);
+ /* Get connector type */
+ if (fields & LIBGAMMA_CRTC_INFO_CONNECTOR_TYPE)
+ e |= get_connector_type(this);
+ /* Get additional output data, excluding EDID */
+ e |= read_output_data(this, output_info);
+ if (fields & LIBGAMMA_CRTC_INFO_MACRO_VIEWPORT)
+ e |= this->width_mm_error | this->height_mm_error;
+ e |= (fields & LIBGAMMA_CRTC_INFO_SUBPIXEL_ORDER) ? this->subpixel_order_error : 0;
+
+ /* If we do not want any EDID information, jump */
+ if (!(fields & LIBGAMMA_CRTC_INFO_MACRO_EDID))
+ goto cont;
+ /* If there is not monitor that report error in EDID related fields */
+ if (!this->active) {
+ e |= this->edid_error = this->gamma_error = this->width_mm_edid_error
+ = this->height_mm_edid_error = LIBGAMMA_NOT_CONNECTED;
+ goto cont;
+ }
+ /* Get EDID */
+ e |= get_edid(this, crtc, output);
+ if (!this->edid) {
+ this->gamma_error = this->width_mm_edid_error = this->height_mm_edid_error = this->edid_error;
+ goto cont;
+ }
+ /* Parse EDID */
+ if ((fields & (LIBGAMMA_CRTC_INFO_MACRO_EDID ^ LIBGAMMA_CRTC_INFO_EDID)))
+ e |= libgamma_internal_parse_edid(this, fields);
+
+cont:
+ /* Get gamma ramp size */
+ e |= (fields & LIBGAMMA_CRTC_INFO_GAMMA_SIZE) ? get_gamma_ramp_size(this, crtc) : 0;
+ /* Store gamma ramp depth. */
+ this->gamma_depth = 16;
+ /* X RandR does not support quering gamma ramp support. */
+ e |= this->gamma_support_error = _E(LIBGAMMA_CRTC_INFO_GAMMA_SUPPORT);
+
+ /* Free the EDID after us */
+ if (free_edid) {
+ free(this->edid);
+ this->edid = NULL;
+ }
+ /* Free the output name after us */
+ if (free_name) {
+ free(this->connector_name);
+ this->connector_name = NULL;
+ }
+
+ free(output_info);
+ return e ? -1 : 0;
+
+#undef _E
+}
+
+
+/**
+ * Get the current gamma ramps for a CRTC, 16-bit gamma-depth 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_x_randr_crtc_get_gamma_ramps16(libgamma_crtc_state_t *restrict this, libgamma_gamma_ramps16_t *restrict ramps)
+{
+ xcb_connection_t *restrict connection = this->partition->site->data;
+ xcb_randr_get_crtc_gamma_cookie_t cookie;
+ xcb_randr_get_crtc_gamma_reply_t *restrict reply;
+ xcb_generic_error_t *error;
+ uint16_t *restrict red;
+ uint16_t *restrict green;
+ uint16_t *restrict blue;
+
+#ifdef DEBUG
+ /* Gamma ramp 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 */
+ cookie = xcb_randr_get_crtc_gamma(connection, *(xcb_randr_crtc_t *)this->data);
+ reply = xcb_randr_get_crtc_gamma_reply(connection, cookie, &error);
+
+ /* Check for errors */
+ if (error)
+ return translate_error(error->error_code, LIBGAMMA_GAMMA_RAMP_READ_FAILED, 0);
+
+ /* Get current gamma ramps from response */
+ red = xcb_randr_get_crtc_gamma_red(reply);
+ green = xcb_randr_get_crtc_gamma_green(reply);
+ blue = xcb_randr_get_crtc_gamma_blue(reply);
+ /* Copy over the gamma ramps to our memory */
+ memcpy(ramps->red, red, ramps->red_size * sizeof(uint16_t));
+ memcpy(ramps->green, green, ramps->green_size * sizeof(uint16_t));
+ memcpy(ramps->blue, blue, ramps->blue_size * sizeof(uint16_t));
+
+ free(reply);
+ return 0;
+}
+
+
+/**
+ * Set the gamma ramps for a CRTC, 16-bit gamma-depth 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_x_randr_crtc_set_gamma_ramps16(libgamma_crtc_state_t *restrict this, libgamma_gamma_ramps16_t ramps)
+{
+ xcb_connection_t *restrict connection = this->partition->site->data;
+ xcb_void_cookie_t cookie;
+ xcb_generic_error_t *restrict error;
+#ifdef DEBUG
+ /* Gamma ramp 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 */
+ cookie = xcb_randr_set_crtc_gamma_checked(connection, *(xcb_randr_crtc_t*)this->data,
+ (uint16_t)ramps.red_size, ramps.red, ramps.green, ramps.blue);
+ /* Check for errors */
+ error = xcb_request_check(connection, cookie);
+ if (error)
+ return translate_error(error->error_code, LIBGAMMA_GAMMA_RAMP_WRITE_FAILED, 0);
+ return 0;
+}
+
+
+#ifdef __GNUC__
+# pragma GCC diagnostic pop
+#endif