pinebuds/utils/list/list.c

/***************************************************************************
 *
 * Copyright 2015-2019 BES.
 * All rights reserved. All unpublished rights reserved.
 *
 * No part of this work may be used or reproduced in any form or by any
 * means, or stored in a database or retrieval system, without prior written
 * permission of BES.
 *
 * Use of this work is governed by a license granted by BES.
 * This work contains confidential and proprietary information of
 * BES. which is protected by copyright, trade secret,
 * trademark and other intellectual property rights.
 *
 ****************************************************************************/
#include "list.h"
#include "cmsis_os.h"
#include "hal_trace.h"
#include "stdio.h"
#include "string.h"

osPoolId list_t_mempool = NULL;
osPoolDef(list_t_mempool, 3, list_t);
osPoolId list_node_t_mempool = NULL;
osPoolDef(list_node_t_mempool, 50, list_node_t);

static list_node_t *list_free_node_(list_t *list, list_node_t *node);

int list_init(void) {
  if (list_t_mempool == NULL)
    list_t_mempool = osPoolCreate(osPool(list_t_mempool));

  if (list_node_t_mempool == NULL)
    list_node_t_mempool = osPoolCreate(osPool(list_node_t_mempool));

  return 0;
}

inline static list_node_t *malloc_list_node(void) {
  list_node_t *node = (list_node_t *)osPoolCAlloc(list_node_t_mempool);
  ASSERT(node, "[%s] failed", __func__);
  return node;
}

inline static void free_list_node(list_node_t *node) {
  osPoolFree(list_node_t_mempool, node);
}

inline static list_t *malloc_list(void) {
  list_t *list = (list_t *)osPoolCAlloc(list_t_mempool);
  ASSERT(list, "[%s] failed", __func__);
  return list;
}

inline static void free_list(list_t *list) { osPoolFree(list_t_mempool, list); }

// Returns a new, empty list. Returns NULL if not enough memory could be
// allocated for the list structure. The returned list must be freed with
// |list_free|. The |callback| specifies a function to be called whenever a list
// element is removed from the list. It can be used to release resources held by
// the list element, e.g. memory or file descriptor. |callback| may be NULL if
// no cleanup is necessary on element removal.
list_t *list_new(list_free_cb callback, list_mempool_zmalloc zmalloc,
                 list_mempool_free free) {
  list_t *list = NULL;
  if (zmalloc) {
    list = (list_t *)zmalloc(sizeof(list_t));
    if (list) {
      list->mempool_functions.zmalloc = zmalloc;
      list->mempool_functions.free = free;
      list->free_cb = callback;
    }
  } else {
    list = (list_t *)malloc_list();
    if (list) {
      list->free_cb = callback;
    }
  }
  return list;
}

// Frees the list. This function accepts NULL as an argument, in which case it
// behaves like a no-op.
void list_free(list_t *list) {
  if (list != NULL)
    list_clear(list);
  if (list->mempool_functions.free)
    list->mempool_functions.free(list);
  else
    free_list(list);
}

// Returns true if the list is empty (has no elements), false otherwise.
// Note that a NULL list is not the same as an empty list. This function
// does not accept a NULL list.
bool list_is_empty(const list_t *list) {
  ASSERT(list != NULL, "%s", __func__);
  return (list->length == 0);
}

// Returns the length of the list. This function does not accept a NULL list.
size_t list_length(const list_t *list) {
  ASSERT(list != NULL, "%s", __func__);
  return list->length;
}

// Returns the first element in the list without removing it. |list| may not
// be NULL or empty.
void *list_front(const list_t *list) {
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(!list_is_empty(list), "%s", __func__);
  return list->head->data;
}

// Returns the last element in the list without removing it. |list| may not
// be NULL or empty.
void *list_back(const list_t *list) {
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(!list_is_empty(list), "%s", __func__);

  return list->tail->data;
}

bool list_insert_after(list_t *list, list_node_t *prev_node, void *data) {
  list_node_t *node;
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(prev_node != NULL, "%s", __func__);
  ASSERT(data != NULL, "%s", __func__);

  if (list->mempool_functions.zmalloc)
    node = (list_node_t *)list->mempool_functions.zmalloc(sizeof(list_node_t));
  else
    node = (list_node_t *)malloc_list_node();

  if (!node)
    return false;

  node->next = prev_node->next;
  node->data = data;
  prev_node->next = node;
  if (list->tail == prev_node)
    list->tail = node;
  ++list->length;
  return true;
}

#include "stdio.h"
// Inserts |data| at the beginning of |list|. Neither |data| nor |list| may be
// NULL. This function does not make a copy of |data| so the pointer must remain
// valid at least until the element is removed from the list or the list is
// freed. Returns true if |data| could be inserted, false otherwise (e.g. out of
// memory).
bool list_prepend(list_t *list, void *data) {
  list_node_t *node;
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(data != NULL, "%s", __func__);

  if (list->mempool_functions.zmalloc)
    node = (list_node_t *)list->mempool_functions.zmalloc(sizeof(list_node_t));
  else
    node = (list_node_t *)malloc_list_node();

  if (!node)
    return false;
  node->next = list->head;
  node->data = data;
  list->head = node;
  if (list->tail == NULL)
    list->tail = list->head;
  ++list->length;
  return true;
}

// Inserts |data| at the end of |list|. Neither |data| nor |list| may be NULL.
// This function does not make a copy of |data| so the pointer must remain valid
// at least until the element is removed from the list or the list is freed.
// Returns true if |data| could be inserted, false otherwise (e.g. out of
// memory).
bool list_append(list_t *list, void *data) {
  list_node_t *node;
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(data != NULL, "%s", __func__);

  if (list->mempool_functions.zmalloc)
    node = (list_node_t *)list->mempool_functions.zmalloc(sizeof(list_node_t));
  else
    node = (list_node_t *)malloc_list_node();

  if (!node)
    return false;
  node->next = NULL;
  node->data = data;
  if (list->tail == NULL) {
    list->head = node;
    list->tail = node;
  } else {
    list->tail->next = node;
    list->tail = node;
  }
  ++list->length;
  return true;
}

// Removes |data| from the list. Neither |list| nor |data| may be NULL. If
// |data| is inserted multiple times in the list, this function will only remove
// the first instance. If a free function was specified in |list_new|, it will
// be called back with |data|. This function returns true if |data| was found in
// the list and removed, false otherwise.
bool list_remove(list_t *list, void *data) {
  list_node_t *prev, *node;
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(data != NULL, "%s", __func__);

  if (list_is_empty(list))
    return false;

  if (list->head->data == data) {
    list_node_t *next = list_free_node_(list, list->head);
    if (list->tail == list->head)
      list->tail = next;
    list->head = next;
    return true;
  }

  for (prev = list->head, node = list->head->next; node;
       prev = node, node = node->next)
    if (node->data == data) {
      prev->next = list_free_node_(list, node);
      if (list->tail == node)
        list->tail = prev;
      return true;
    }

  return false;
}

// Removes all elements in the list. Calling this function will return the list
// to the same state it was in after |list_new|. |list| may not be NULL.
void list_clear(list_t *list) {
  list_node_t *node;
  ASSERT(list != NULL, "%s", __func__);
  for (node = list->head; node;)
    node = list_free_node_(list, node);
  list->head = NULL;
  list->tail = NULL;
  list->length = 0;
}

// Iterates through the entire |list| and calls |callback| for each data
// element. If the list is empty, |callback| will never be called. It is safe to
// mutate the list inside the callback. If an element is added before the node
// being visited, there will be no callback for the newly-inserted node. Neither
// |list| nor |callback| may be NULL.
void list_foreach(const list_t *list, list_iter_cb callback) {
  list_node_t *node;
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(callback != NULL, "%s", __func__);

  for (node = list->head; node;) {
    list_node_t *next = node->next;
    callback(node->data);
    node = next;
  }
}

// Returns an iterator to the first element in |list|. |list| may not be NULL.
// The returned iterator is valid as long as it does not equal the value
// returned by |list_end|.
list_node_t *list_begin(const list_t *list) {
  ASSERT(list != NULL, "%s", __func__);
  return list->head;
}

// Returns an iterator that points past the end of the list. In other words,
// this function returns the value of an invalid iterator for the given list.
// When an iterator has the same value as what's returned by this function, you
// may no longer call |list_next| with the iterator. |list| may not be NULL.
list_node_t *list_end(const list_t *list) {
  ASSERT(list != NULL, "%s", __func__);
  return NULL;
}

// Given a valid iterator |node|, this function returns the next value for the
// iterator. If the returned value equals the value returned by |list_end|, the
// iterator has reached the end of the list and may no longer be used for any
// purpose.
list_node_t *list_next(const list_node_t *node) {
  ASSERT(node != NULL, "%s", __func__);
  return node->next;
}

// Returns the value stored at the location pointed to by the iterator |node|.
// |node| must not equal the value returned by |list_end|.
void *list_node(const list_node_t *node) {
  ASSERT(node != NULL, "%s", __func__);
  return node->data;
}

static list_node_t *list_free_node_(list_t *list, list_node_t *node) {
  list_node_t *next;
  ASSERT(list != NULL, "%s", __func__);
  ASSERT(node != NULL, "%s", __func__);

  next = node->next;

  if (list->free_cb)
    list->free_cb(node->data);

  if (list->mempool_functions.free)
    list->mempool_functions.free(node);
  else
    free_list_node(node);

  --list->length;

  return next;
}