RetroArch/libretro-common/lists/nested_list.c

614 lines
16 KiB
C

/* Copyright (C) 2010-2020 The RetroArch team
*
* ---------------------------------------------------------------------------------------
* The following license statement only applies to this file (nested_list.c).
* ---------------------------------------------------------------------------------------
*
* Permission is hereby granted, free of charge,
* to any person obtaining a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <string/stdstring.h>
#include <lists/string_list.h>
#include <array/rbuf.h>
#include <array/rhmap.h>
#include <lists/nested_list.h>
struct nested_list_item
{
nested_list_item_t *parent_item;
nested_list_t *parent_list;
nested_list_t *children;
char *id;
const void *value;
};
struct nested_list
{
nested_list_item_t **items;
nested_list_item_t **item_map;
};
/**************************************/
/* Initialisation / De-Initialisation */
/**************************************/
/* Forward declaration - required since
* nested_list_free_list() is recursive */
static void nested_list_free_list(nested_list_t *list);
/* Frees contents of a nested list item */
static void nested_list_free_item(nested_list_item_t *item)
{
if (!item)
return;
item->parent_item = NULL;
item->parent_list = NULL;
if (item->children)
{
nested_list_free_list(item->children);
item->children = NULL;
}
if (item->id)
{
free(item->id);
item->id = NULL;
}
item->value = NULL;
free(item);
}
/* Frees contents of a nested list */
static void nested_list_free_list(nested_list_t *list)
{
size_t i;
if (!list)
return;
for (i = 0; i < RBUF_LEN(list->items); i++)
nested_list_free_item(list->items[i]);
RBUF_FREE(list->items);
RHMAP_FREE(list->item_map);
free(list);
}
/**
* nested_list_init:
*
* Creates a new empty nested list. Returned pointer
* must be freed using nested_list_free.
*
* Returns: Valid nested_list_t pointer if successful,
* otherwise NULL.
*/
nested_list_t *nested_list_init(void)
{
/* Create nested list */
nested_list_t *list = (nested_list_t*)malloc(sizeof(*list));
if (!list)
return NULL;
/* Initialise members */
list->items = NULL;
list->item_map = NULL;
return list;
}
/**
* nested_list_free:
* @list : pointer to nested_list_t object
*
* Frees specified nested list.
*/
void nested_list_free(nested_list_t *list)
{
nested_list_free_list(list);
}
/***********/
/* Setters */
/***********/
/* Creates and adds a new item to the specified
* nested list. Returns NULL if item matching 'id'
* already exists */
static nested_list_item_t *nested_list_add_item_to_list(nested_list_t *list,
nested_list_item_t *parent_item, const char *id, const void *value)
{
size_t num_items = 0;
nested_list_item_t *new_item = NULL;
nested_list_t *child_list = NULL;
if (!list || string_is_empty(id))
goto end;
num_items = RBUF_LEN(list->items);
/* Ensure that item does not already exist */
if (RHMAP_HAS_STR(list->item_map, id))
goto end;
/* Attempt to allocate a buffer slot for the
* new item */
if (!RBUF_TRYFIT(list->items, num_items + 1))
goto end;
/* Create new empty child list */
child_list = nested_list_init();
if (!child_list)
goto end;
/* Create new list item */
new_item = (nested_list_item_t*)malloc(sizeof(*new_item));
if (!new_item)
{
nested_list_free(child_list);
goto end;
}
/* Assign members */
new_item->parent_item = parent_item;
new_item->parent_list = list;
new_item->children = child_list;
new_item->id = strdup(id);
new_item->value = value;
/* Increment item buffer size */
RBUF_RESIZE(list->items, num_items + 1);
/* Add new item to buffer */
list->items[num_items] = new_item;
/* Update map */
RHMAP_SET_STR(list->item_map, id, new_item);
end:
return new_item;
}
/**
* nested_list_add_item:
*
* @list : pointer to nested_list_t object
* @address : a delimited list of item identifiers,
* corresponding to item 'levels'
* @delim : delimiter to use when splitting @address
* into individual ids
* @value : optional value (user data) associated with
* new list item. This is added to the last
* item specified by @address
*
* Appends a new item to the specified nested list.
* If @delim is NULL, item is added to the top level
* list (@list itself) with id equal to @address.
* Otherwise, @address is split by @delim and each
* id is added as new 'layer'. For example:
*
* > @address = "one:two:three", @delim = ":" will
* produce:
* top_level_list:one
* `- "one" list:two
* `- "two" list:three
* where @value is assigned to the "two" list:three
* item.
*
* Returns: true if successful, otherwise false. Will
* always return false if item specified by @address
* already exists in the nested list.
*/
bool nested_list_add_item(nested_list_t *list,
const char *address, const char *delim, const void *value)
{
struct string_list id_list = {0};
const char *top_id = NULL;
bool success = false;
if (!list || string_is_empty(address))
goto end;
/* If delim is NULL or address contains a single
* token, then we are adding an item to the top
* level list */
if (string_is_empty(delim))
top_id = address;
else
{
string_list_initialize(&id_list);
if (!string_split_noalloc(&id_list, address, delim) ||
(id_list.size < 1))
goto end;
if (id_list.size == 1)
top_id = id_list.elems[0].data;
}
if (!string_is_empty(top_id))
{
if (nested_list_add_item_to_list(list, NULL, top_id, value))
success = true;
}
else
{
nested_list_t *current_list = list;
nested_list_item_t *parent_item = NULL;
nested_list_item_t *next_item = NULL;
size_t i;
/* Loop over list item ids */
for (i = 0; i < id_list.size; i++)
{
const char *id = id_list.elems[i].data;
if (string_is_empty(id))
goto end;
/* If this is the last entry in the id list,
* then we are adding the item itself */
if (i == (id_list.size - 1))
{
if (nested_list_add_item_to_list(current_list,
parent_item, id, value))
success = true;
break;
}
/* Otherwise, id corresponds to a 'category' */
else
{
/* Check whether category item already exists */
next_item = RHMAP_GET_STR(current_list->item_map, id);
/* Create it, if required */
if (!next_item)
next_item = nested_list_add_item_to_list(current_list,
parent_item, id, NULL);
if (!next_item)
break;
/* Update pointers */
parent_item = next_item;
current_list = next_item->children;
}
}
}
end:
string_list_deinitialize(&id_list);
return success;
}
/***********/
/* Getters */
/***********/
/**
* nested_list_get_size:
*
* @list : pointer to nested_list_t object
*
* Fetches the current size (number of items) in
* the specified list.
*
* Returns: list size.
*/
size_t nested_list_get_size(nested_list_t *list)
{
if (!list)
return 0;
return RBUF_LEN(list->items);
}
/**
* nested_list_get_item:
*
* @list : pointer to nested_list_t object
* @address : a delimited list of item identifiers,
* corresponding to item 'levels'
* @delim : delimiter to use when splitting @address
* into individual ids
*
* Searches for (and returns) the list item corresponding
* to @address. If @delim is NULL, the top level list
* (@list itself) is searched for an item with an id
* equal to @address. Otherwise, @address is split by
* @delim and each id is searched for in a subsequent
* list level.
*
* Returns: valid nested_list_item_t pointer if item
* is found, otherwise NULL.
*/
nested_list_item_t *nested_list_get_item(nested_list_t *list,
const char *address, const char *delim)
{
nested_list_item_t *search_item = NULL;
struct string_list id_list = {0};
const char *top_id = NULL;
if (!list || string_is_empty(address))
goto end;
/* If delim is NULL or address contains a single
* token, then we are fetching an item from the
* top level list */
if (string_is_empty(delim))
top_id = address;
else
{
string_list_initialize(&id_list);
if (!string_split_noalloc(&id_list, address, delim) ||
(id_list.size < 1))
goto end;
if (id_list.size == 1)
top_id = id_list.elems[0].data;
}
if (!string_is_empty(top_id))
search_item = RHMAP_GET_STR(list->item_map, top_id);
else
{
/* Otherwise, search 'category' levels */
nested_list_t *current_list = list;
nested_list_item_t *next_item = NULL;
size_t i;
/* Loop over list item ids */
for (i = 0; i < id_list.size; i++)
{
const char *id = id_list.elems[i].data;
if (string_is_empty(id))
goto end;
/* If this is the last entry in the id list,
* then we are searching for the item itself */
if (i == (id_list.size - 1))
{
search_item = RHMAP_GET_STR(current_list->item_map, id);
break;
}
/* Otherwise, id corresponds to a 'category' */
else
{
next_item = RHMAP_GET_STR(current_list->item_map, id);
if (!next_item)
break;
/* Update pointer */
current_list = next_item->children;
}
}
}
end:
string_list_deinitialize(&id_list);
return search_item;
}
/**
* nested_list_get_item_idx:
*
* @list : pointer to nested_list_t object
* @idx : item index
*
* Fetches the item corresponding to index @idx in
* the top level list (@list itself) of the specified
* nested list.
*
* Returns: valid nested_list_item_t pointer if item
* exists, otherwise NULL.
*/
nested_list_item_t *nested_list_get_item_idx(nested_list_t *list,
size_t idx)
{
if (!list || (idx >= RBUF_LEN(list->items)))
return NULL;
return list->items[idx];
}
/**
* nested_list_item_get_parent:
*
* @list_item : pointer to nested_list_item_t object
*
* Fetches the parent item of the specified nested
* list item. If returned value is NULL, specified
* nested list item belongs to a top level list.
*
* Returns: valid nested_list_item_t pointer if item
* has a parent, otherwise NULL.
*/
nested_list_item_t *nested_list_item_get_parent(nested_list_item_t *list_item)
{
if (!list_item)
return NULL;
return list_item->parent_item;
}
/**
* nested_list_item_get_parent_list:
*
* @list_item : pointer to nested_list_item_t object
*
* Fetches a pointer to the nested list of which the
* specified list item is a direct member.
*
* Returns: valid nested_list_t pointer if successful,
* otherwise NULL.
*/
nested_list_t *nested_list_item_get_parent_list(nested_list_item_t *list_item)
{
if (!list_item)
return NULL;
return list_item->parent_list;
}
/**
* nested_list_item_get_children:
*
* @list_item : pointer to nested_list_item_t object
*
* Fetches a pointer to the nested list of child items
* belonging to the specified list item.
*
* Returns: valid nested_list_t pointer if item has
* children, otherwise NULL.
*/
nested_list_t *nested_list_item_get_children(nested_list_item_t *list_item)
{
if (!list_item ||
!list_item->children ||
(RBUF_LEN(list_item->children->items) < 1))
return NULL;
return list_item->children;
}
/**
* nested_list_item_get_id:
*
* @list_item : pointer to nested_list_item_t object
*
* Fetches the id string of the specified list item,
* as set by nested_list_add_item().
*
* Returns: item id if successful, otherwise NULL.
*/
const char *nested_list_item_get_id(nested_list_item_t *list_item)
{
if (!list_item)
return NULL;
return list_item->id;
}
/**
* nested_list_item_get_address:
*
* @list_item : pointer to nested_list_item_t object
* @delim : delimiter to use when concatenating
* individual item ids into a an @address
* string
* @address : a delimited list of item identifiers,
* corresponding to item 'levels'
* @len : length of supplied @address char array
* Fetches a compound @address string corresponding to
* the specified item's 'position' in the top level
* nested list of which it is a member. The resultant
* @address may be used to find the item when calling
* nested_list_get_item() on the top level nested list.
*
* Returns: true if successful, otherwise false.
*/
bool nested_list_item_get_address(nested_list_item_t *list_item,
const char *delim, char *address, size_t len)
{
nested_list_item_t *current_item = list_item;
struct string_list id_list = {0};
bool success = false;
union string_list_elem_attr attr;
size_t i;
if (!list_item ||
string_is_empty(delim) ||
!address ||
(len < 1))
goto end;
address[0] = '\0';
attr.i = 0;
/* If this is an item of the top level
* list, just copy the item id directly */
if (!list_item->parent_item)
{
strlcpy(address, list_item->id, len);
success = true;
goto end;
}
/* ...otherwise we have to combine the ids
* of the item and all of its 'ancestors' */
string_list_initialize(&id_list);
/* Fetch all ids */
do
{
const char *id = current_item->id;
if (string_is_empty(id) ||
!string_list_append(&id_list, id, attr))
goto end;
current_item = current_item->parent_item;
}
while (current_item);
if (id_list.size < 1)
goto end;
/* Build address string */
for (i = id_list.size; i > 0; i--)
{
const char *id = id_list.elems[i - 1].data;
if (string_is_empty(id))
goto end;
strlcat(address, id, len);
if (i > 1)
strlcat(address, delim, len);
}
success = true;
end:
string_list_deinitialize(&id_list);
return success;
}
/**
* nested_list_item_get_value:
*
* @list_item : pointer to nested_list_item_t object
*
* Fetches the value (user data) associated with the
* specified list item.
*
* Returns: pointer to user data if set, otherwise
* NULL.
*/
const void *nested_list_item_get_value(nested_list_item_t *list_item)
{
if (!list_item)
return NULL;
return list_item->value;
}