Flowgrind
Advanced TCP traffic generator
Data Structures | Functions
fg_list.h File Reference

Generic doubly linked list implementation. More...

#include "config.h"
#include <stddef.h>

Go to the source code of this file.

Data Structures

struct  linked_list
 A doubly linked list. More...
 
struct  list_node
 Single element in a doubly linked list. More...
 

Functions

const struct list_node * fg_list_back (struct linked_list *const list)
 Returns the last element of the list. More...
 
int fg_list_clear (struct linked_list *const list)
 Removes and destroys all elements from the list, leaving it with a size of 0. More...
 
const struct list_node * fg_list_front (struct linked_list *const list)
 Returns the first element of the list. More...
 
int fg_list_init (struct linked_list *const list)
 Initializes the list by setting its head and tail to NULL and its size to 0. More...
 
void * fg_list_pop_back (struct linked_list *const list)
 Removes the last element in the list, effectively reducing its size by one. More...
 
void * fg_list_pop_front (struct linked_list *const list)
 Removes the first element in the list, effectively reducing its size by one. More...
 
int fg_list_push_back (struct linked_list *const list, void *const data)
 Inserts a new element at the end of the list. More...
 
int fg_list_push_front (struct linked_list *const list, void *const data)
 Inserts a new element at the beginning of the list. More...
 
int fg_list_remove (struct linked_list *const list, const void *const data)
 Removes from the list the first element whose data points to data. More...
 
size_t fg_list_size (struct linked_list *const list)
 Returns the number of elements in the list. More...
 

Detailed Description

Generic doubly linked list implementation.

Definition in file fg_list.h.

Function Documentation

◆ fg_list_back()

const struct list_node* fg_list_back ( struct linked_list *const  list)

Returns the last element of the list.

The element is not removed from the list.

Parameters
[in]listto operate on
Returns
a pointer to the last element in list

Definition at line 57 of file fg_list.c.

58 {
59  if (!list)
60  return NULL;
61 
62  return list->tail;
63 }

◆ fg_list_clear()

int fg_list_clear ( struct linked_list *const  list)

Removes and destroys all elements from the list, leaving it with a size of 0.

Parameters
[in]listto operate on
Returns
zero on success, non-zero otherwise

Definition at line 219 of file fg_list.c.

220 {
221  if (!list)
222  return -1;
223 
224  while (fg_list_size(list)) {
225  void * data = fg_list_pop_front(list);
226  free(data);
227  }
228 
229  return 0;
230 }

◆ fg_list_front()

const struct list_node* fg_list_front ( struct linked_list *const  list)

Returns the first element of the list.

The element is not removed from the list.

Parameters
[in]listto operate on
Returns
a pointer to the first element in list

Definition at line 49 of file fg_list.c.

50 {
51  if (!list)
52  return NULL;
53 
54  return list->head;
55 }

◆ fg_list_init()

int fg_list_init ( struct linked_list *const  list)

Initializes the list by setting its head and tail to NULL and its size to 0.

Parameters
[in]listlist to initialize
Returns
zero on success, non-zero otherwise

Definition at line 34 of file fg_list.c.

35 {
36  if (!list)
37  return -1;
38  if (list->head)
39  if (!fg_list_clear(list))
40  return -2;
41 
42  list->head = NULL;
43  list->tail = NULL;
44  list->size = 0;
45 
46  return 0;
47 }

◆ fg_list_pop_back()

void* fg_list_pop_back ( struct linked_list *const  list)

Removes the last element in the list, effectively reducing its size by one.

This destroys the removed element. The data contained in this element will not be modified.

Parameters
[in]listto operate on
Returns
pointer to the data that was contained in the removed element, NULL on failure

Definition at line 188 of file fg_list.c.

189 {
190  if (!list)
191  return NULL;
192  if (!list->tail)
193  return NULL;
194 
195  struct list_node *tail = list->tail;
196  void *data = tail->data;
197 
198  if (tail->previous)
199  tail->previous->next = NULL;
200  if (list->tail == list->head)
201  list->head = NULL;
202 
203  list->tail = tail->previous;
204 
205  free(tail);
206  --list->size;
207 
208  return data;
209 }

◆ fg_list_pop_front()

void* fg_list_pop_front ( struct linked_list *const  list)

Removes the first element in the list, effectively reducing its size by one.

This destroys the removed element. The data contained in this element will not be modified.

Parameters
[in]listto operate on
Returns
pointer to the data that was contained in the removed element, NULL on failure

Definition at line 144 of file fg_list.c.

145 {
146  if (!list)
147  return NULL;
148  if (!list->head)
149  return NULL;
150 
151  struct list_node *head = list->head;
152 
153  if (list->head == list->tail)
154  list->tail = NULL;
155  if (head->next)
156  head->next->previous = NULL;
157 
158  list->head = head->next;
159  void *data = head->data;
160 
161  free(head);
162  --list->size;
163 
164  return data;
165 }

◆ fg_list_push_back()

int fg_list_push_back ( struct linked_list *const  list,
void *const  data 
)

Inserts a new element at the end of the list.

The data of the new element will point to the same memory location as data. This effectively increases the list's size by one.

Parameters
[in]listto operate on
[in]dataof inserted element
Returns
zero on success, non-zero otherwise

Definition at line 167 of file fg_list.c.

168 {
169  if (!list)
170  return -1;
171 
172  struct list_node *new_node = create_node(data, list->tail, NULL);
173 
174  if (!new_node)
175  return -5;
176 
177  if (!list->head)
178  list->head = new_node;
179  if (list->tail)
180  list->tail->next = new_node;
181 
182  list->tail = new_node;
183  ++list->size;
184 
185  return 0;
186 }

◆ fg_list_push_front()

int fg_list_push_front ( struct linked_list *const  list,
void *const  data 
)

Inserts a new element at the beginning of the list.

The data of the new element will point to the same memory location as data. This effectively increases the list's size by one.

Parameters
[in]listto operate on
[in]dataof inserted element
Returns
zero on success, non-zero otherwise

Definition at line 123 of file fg_list.c.

124 {
125  if (!list)
126  return -1;
127 
128  struct list_node *new_node = create_node(data, NULL, list->head);
129 
130  if (!new_node)
131  return -5;
132 
133  if (!list->head)
134  list->tail = new_node;
135  else
136  list->head->previous = new_node;
137 
138  list->head = new_node;
139  ++list->size;
140 
141  return 0;
142 }

◆ fg_list_remove()

int fg_list_remove ( struct linked_list *const  list,
const void *const  data 
)

Removes from the list the first element whose data points to data.

It reduces the list size by one. The data contained in this element will not be modified.

Parameters
[in]listto operate on
[in]dataof the element to be removed
Returns
zero on success, non-zero otherwise

Definition at line 65 of file fg_list.c.

66 {
67  if (!list)
68  return -1;
69  if (!list->head)
70  return -3;
71 
72  struct list_node *node = list->head;
73 
74  while (node->data != data) {
75  node = node->next;
76  if (!node)
77  return -4;
78  }
79 
80  if (list->head == node)
81  list->head = node->next;
82  if (list->tail == node)
83  list->tail = node->previous;
84  if (node->previous)
85  node->previous->next = node->next;
86  if (node->next)
87  node->next->previous = node->previous;
88 
89  free(node);
90  --list->size;
91 
92  return 0;
93 }

◆ fg_list_size()

size_t fg_list_size ( struct linked_list *const  list)

Returns the number of elements in the list.

Parameters
[in]listto operate on
Returns
the number of elements in the list

Definition at line 211 of file fg_list.c.

212 {
213  if (!list)
214  return -1;
215 
216  return list->size;
217 }
fg_list_size
size_t fg_list_size(struct linked_list *const list)
Returns the number of elements in the list.
Definition: fg_list.c:211
create_node
static struct list_node * create_node(void *const data, struct list_node *const previous, struct list_node *const next)
Creates a new list element on the heap.
Definition: fg_list.c:107
list_node::data
void * data
Pointer to user defined data stored with this node.
Definition: fg_list.h:38
fg_list_clear
int fg_list_clear(struct linked_list *const list)
Removes and destroys all elements from the list, leaving it with a size of 0.
Definition: fg_list.c:219
list_node::previous
struct list_node * previous
Pointer to the next node in the list.
Definition: fg_list.h:42
linked_list::head
struct list_node * head
Pointer to the first element in the list.
Definition: fg_list.h:48
linked_list::size
size_t size
Size of the list i.e.
Definition: fg_list.h:52
fg_list_pop_front
void * fg_list_pop_front(struct linked_list *const list)
Removes the first element in the list, effectively reducing its size by one.
Definition: fg_list.c:144
linked_list::tail
struct list_node * tail
Pointer to the last element in the list.
Definition: fg_list.h:50
list_node
Single element in a doubly linked list.
Definition: fg_list.h:36
list_node::next
struct list_node * next
Pointer to the previous node in the list.
Definition: fg_list.h:40