source: mainline/uspace/lib/usbhid/src/hidpath.c

/*
 * Copyright (c) 2011 Matej Klonfar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libusbhid
 * @{
 */
/** @file
 * HID report descriptor and report data parser implementation.
 */
#include <usb/hid/hidparser.h>
#include <errno.h>
#include <stdio.h>
#include <mem.h>
#include <stdlib.h>
#include <usb/debug.h>
#include <assert.h>

/**
 * Compares two usages if they are same or not or one of the usages is not
 * set.
 *
 * @param usage1
 * @param usage2
 * @return boolean
 */
#define USB_HID_SAME_USAGE(usage1, usage2)              \
        ((usage1 == usage2) || (usage1 == 0) || (usage2 == 0))

/**
 * Compares two usage pages if they are same or not or one of them is not set.
 *
 * @param page1
 * @param page2
 * @return boolean
 */
#define USB_HID_SAME_USAGE_PAGE(page1, page2)   \
        ((page1 == page2) || (page1 == 0) || (page2 == 0))

/**
 * Appends one item (couple of usage_path and usage) into the usage path
 * structure
 *
 * @param usage_path Usage path structure
 * @param usage_page Usage page constant
 * @param usage Usage constant
 * @return Error code
 */
errno_t usb_hid_report_path_append_item(usb_hid_report_path_t *usage_path,
    int32_t usage_page, int32_t usage)
{
        usb_hid_report_usage_path_t *item =
            malloc(sizeof(usb_hid_report_usage_path_t));

        if (item == NULL) {
                return ENOMEM;
        }
        link_initialize(&item->rpath_items_link);

        item->usage = usage;
        item->usage_page = usage_page;
        item->flags = 0;

        list_append (&item->rpath_items_link, &usage_path->items);
        usage_path->depth++;
        return EOK;
}

/**
 * Removes last item from the usage path structure
 * @param usage_path
 * @return void
 */
void usb_hid_report_remove_last_item(usb_hid_report_path_t *usage_path)
{
        link_t *item_link;
        usb_hid_report_usage_path_t *item;

        if (!list_empty(&usage_path->items)) {
                item_link = list_last(&usage_path->items);
                item = list_get_instance(item_link,
                    usb_hid_report_usage_path_t, rpath_items_link);
                list_remove(item_link);
                usage_path->depth--;
                free(item);
        }
}

/**
 * Nulls last item of the usage path structure.
 *
 * @param usage_path
 * @return void
 */
void usb_hid_report_null_last_item(usb_hid_report_path_t *usage_path)
{
        usb_hid_report_usage_path_t *item;

        if (!list_empty(&usage_path->items)) {
                item = list_get_instance(list_last(&usage_path->items),
                    usb_hid_report_usage_path_t, rpath_items_link);

                memset(item, 0, sizeof(usb_hid_report_usage_path_t));
        }
}

/**
 * Modifies last item of usage path structure by given usage page or usage
 *
 * @param usage_path Opaque usage path structure
 * @param tag Class of currently processed tag (Usage page tag falls into Global
 * class but Usage tag into the Local)
 * @param data Value of the processed tag
 * @return void
 */
void usb_hid_report_set_last_item(usb_hid_report_path_t *usage_path,
    int32_t tag, int32_t data)
{
        usb_hid_report_usage_path_t *item;

        if (!list_empty(&usage_path->items)) {
                item = list_get_instance(list_last(&usage_path->items),
                    usb_hid_report_usage_path_t, rpath_items_link);

                switch (tag) {
                case USB_HID_TAG_CLASS_GLOBAL:
                        item->usage_page = data;
                        break;
                case USB_HID_TAG_CLASS_LOCAL:
                        item->usage = data;
                        break;
                }
        }
}

void usb_hid_print_usage_path(usb_hid_report_path_t *path)
{
        usb_log_debug("USAGE_PATH FOR RId(%d):", path->report_id);
        usb_log_debug("\tLENGTH: %d", path->depth);

        list_foreach(path->items, rpath_items_link,
            usb_hid_report_usage_path_t, path_item) {

                usb_log_debug("\tUSAGE_PAGE: %X", path_item->usage_page);
                usb_log_debug("\tUSAGE: %X", path_item->usage);
                usb_log_debug("\tFLAGS: %d", path_item->flags);
        }
}

/** Compare two usage paths structures
 *
 * @param report_path Usage path structure to compare with @path
 * @param path        Usage patrh structure to compare
 * @param flags       Flags determining the mode of comparison
 *
 * @return 0 if both paths are identical, non zero number otherwise
 *
 */
int usb_hid_report_compare_usage_path(usb_hid_report_path_t *report_path,
    usb_hid_report_path_t *path, int flags)
{
        usb_hid_report_usage_path_t *report_item;
        usb_hid_report_usage_path_t *path_item;

        link_t *report_link;
        link_t *path_link;

        int only_page;

        if (report_path->report_id != path->report_id) {
                if (path->report_id != 0) {
                        return 1;
                }
        }

        // Empty path match all others
        if (path->depth == 0) {
                return 0;
        }

        if ((only_page = flags & USB_HID_PATH_COMPARE_USAGE_PAGE_ONLY) != 0) {
                flags -= USB_HID_PATH_COMPARE_USAGE_PAGE_ONLY;
        }

        switch (flags) {
        case USB_HID_PATH_COMPARE_ANYWHERE:
                /*
                 * Path is somewhere in report_path
                 */
                if (path->depth != 1) {
                        return 1;
                }

                path_link = list_first(&path->items);
                path_item = list_get_instance(path_link,
                    usb_hid_report_usage_path_t, rpath_items_link);

                list_foreach(report_path->items, rpath_items_link,
                    usb_hid_report_usage_path_t, report_item) {
                        if (USB_HID_SAME_USAGE_PAGE(report_item->usage_page,
                            path_item->usage_page)) {

                                if (only_page == 0) {
                                        if (USB_HID_SAME_USAGE(report_item->usage,
                                            path_item->usage))
                                                return 0;
                                } else {
                                        return 0;
                                }
                        }
                }

                return 1;

        case USB_HID_PATH_COMPARE_STRICT:
                /*
                 * The paths must be identical
                 */
                if (report_path->depth != path->depth) {
                        return 1;
                }
                /* Fallthrough */

        case USB_HID_PATH_COMPARE_BEGIN:
                /*
                 * Path is prefix of the report_path
                 */
                report_link = report_path->items.head.next;
                path_link = path->items.head.next;

                while ((report_link != &report_path->items.head) &&
                    (path_link != &path->items.head)) {

                        report_item = list_get_instance(report_link,
                            usb_hid_report_usage_path_t, rpath_items_link);

                        path_item = list_get_instance(path_link,
                            usb_hid_report_usage_path_t, rpath_items_link);

                        if (!USB_HID_SAME_USAGE_PAGE(report_item->usage_page,
                            path_item->usage_page) || ((only_page == 0) &&
                            !USB_HID_SAME_USAGE(report_item->usage,
                            path_item->usage))) {
                                return 1;
                        } else {
                                report_link = report_link->next;
                                path_link = path_link->next;
                        }
                }

                if ((((flags & USB_HID_PATH_COMPARE_BEGIN) != 0) &&
                    (path_link == &path->items.head)) ||
                    ((report_link == &report_path->items.head) &&
                    (path_link == &path->items.head))) {
                        return 0;
                } else {
                        return 1;
                }
                break;

        case USB_HID_PATH_COMPARE_END:
                /*
                 * Path is suffix of report_path
                 */
                report_link = report_path->items.head.prev;
                path_link = path->items.head.prev;

                if (list_empty(&path->items)) {
                        return 0;
                }

                while ((report_link != &report_path->items.head) &&
                    (path_link != &path->items.head)) {
                        report_item = list_get_instance(report_link,
                            usb_hid_report_usage_path_t, rpath_items_link);

                        path_item = list_get_instance(path_link,
                            usb_hid_report_usage_path_t, rpath_items_link);

                        if (!USB_HID_SAME_USAGE_PAGE(report_item->usage_page,
                            path_item->usage_page) || ((only_page == 0) &&
                            !USB_HID_SAME_USAGE(report_item->usage,
                            path_item->usage))) {
                                return 1;
                        } else {
                                report_link = report_link->prev;
                                path_link = path_link->prev;
                        }
                }

                if (path_link == &path->items.head) {
                        return 0;
                } else {
                        return 1;
                }
                break;

        default:
                return -1;
        }
}

/**
 * Allocates and initializes new usage path structure.
 *
 * @return Initialized usage path structure
 */
usb_hid_report_path_t *usb_hid_report_path(void)
{
        usb_hid_report_path_t *path;
        path = malloc(sizeof(usb_hid_report_path_t));
        if (path == NULL) {
                return NULL;
        } else {
                path->depth = 0;
                path->report_id = 0;
                link_initialize(&path->cpath_link);
                list_initialize(&path->items);
                return path;
        }
}

/**
 * Releases given usage path structure.
 *
 * @param path usage path structure to release
 * @return void
 */
void usb_hid_report_path_free(usb_hid_report_path_t *path)
{
        if (path == NULL)
                return;
        while (!list_empty(&path->items)) {
                usb_hid_report_remove_last_item(path);
        }

        assert_link_not_used(&path->cpath_link);
        free(path);
}

/**
 * Clone content of given usage path to the new one
 *
 * @param usage_path Usage path structure to clone
 * @return New copy of given usage path structure
 */
usb_hid_report_path_t *usb_hid_report_path_clone(
    usb_hid_report_path_t *usage_path)
{
        usb_hid_report_usage_path_t *new_path_item;
        usb_hid_report_path_t *new_usage_path = usb_hid_report_path ();

        if (new_usage_path == NULL) {
                return NULL;
        }

        new_usage_path->report_id = usage_path->report_id;

        if (list_empty(&usage_path->items)) {
                return new_usage_path;
        }

        list_foreach(usage_path->items, rpath_items_link,
            usb_hid_report_usage_path_t, path_item) {

                new_path_item = malloc(sizeof(usb_hid_report_usage_path_t));
                if (new_path_item == NULL) {
                        return NULL;
                }

                link_initialize(&new_path_item->rpath_items_link);
                new_path_item->usage_page = path_item->usage_page;
                new_path_item->usage = path_item->usage;
                new_path_item->flags = path_item->flags;

                list_append(&new_path_item->rpath_items_link,
                    &new_usage_path->items);
                new_usage_path->depth++;
        }

        return new_usage_path;
}

/**
 * Sets report id in usage path structure
 *
 * @param path Usage path structure
 * @param report_id Report id to set
 * @return Error code
 */
errno_t usb_hid_report_path_set_report_id(usb_hid_report_path_t *path,
    uint8_t report_id)
{
        if (path == NULL) {
                return EINVAL;
        }

        path->report_id = report_id;
        return EOK;
}

/**
 * @}
 */