1/***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24
25#include "curl_setup.h"
26
27#include <curl/curl.h>
28
29#include "slist.h"
30
31/* The last #include files should be: */
32#include "curl_memory.h"
33#include "memdebug.h"
34
35/* returns last node in linked list */
36static struct curl_slist *slist_get_last(struct curl_slist *list)
37{
38 struct curl_slist *item;
39
40 /* if caller passed us a NULL, return now */
41 if(!list)
42 return NULL;
43
44 /* loop through to find the last item */
45 item = list;
46 while(item->next) {
47 item = item->next;
48 }
49 return item;
50}
51
52/*
53 * Curl_slist_append_nodup() appends a string to the linked list. Rather than
54 * copying the string in dynamic storage, it takes its ownership. The string
55 * should have been malloc()ated. Curl_slist_append_nodup always returns
56 * the address of the first record, so that you can use this function as an
57 * initialization function as well as an append function.
58 * If an error occurs, NULL is returned and the string argument is NOT
59 * released.
60 */
61struct curl_slist *Curl_slist_append_nodup(struct curl_slist *list, char *data)
62{
63 struct curl_slist *last;
64 struct curl_slist *new_item;
65
66 DEBUGASSERT(data);
67
68 new_item = malloc(sizeof(struct curl_slist));
69 if(!new_item)
70 return NULL;
71
72 new_item->next = NULL;
73 new_item->data = data;
74
75 /* if this is the first item, then new_item *is* the list */
76 if(!list)
77 return new_item;
78
79 last = slist_get_last(list);
80 last->next = new_item;
81 return list;
82}
83
84/*
85 * curl_slist_append() appends a string to the linked list. It always returns
86 * the address of the first record, so that you can use this function as an
87 * initialization function as well as an append function. If you find this
88 * bothersome, then simply create a separate _init function and call it
89 * appropriately from within the program.
90 */
91struct curl_slist *curl_slist_append(struct curl_slist *list,
92 const char *data)
93{
94 char *dupdata = strdup(data);
95
96 if(!dupdata)
97 return NULL;
98
99 list = Curl_slist_append_nodup(list, data: dupdata);
100 if(!list)
101 free(dupdata);
102
103 return list;
104}
105
106/*
107 * Curl_slist_duplicate() duplicates a linked list. It always returns the
108 * address of the first record of the cloned list or NULL in case of an
109 * error (or if the input list was NULL).
110 */
111struct curl_slist *Curl_slist_duplicate(struct curl_slist *inlist)
112{
113 struct curl_slist *outlist = NULL;
114 struct curl_slist *tmp;
115
116 while(inlist) {
117 tmp = curl_slist_append(list: outlist, data: inlist->data);
118
119 if(!tmp) {
120 curl_slist_free_all(list: outlist);
121 return NULL;
122 }
123
124 outlist = tmp;
125 inlist = inlist->next;
126 }
127 return outlist;
128}
129
130/* be nice and clean up resources */
131void curl_slist_free_all(struct curl_slist *list)
132{
133 struct curl_slist *next;
134 struct curl_slist *item;
135
136 if(!list)
137 return;
138
139 item = list;
140 do {
141 next = item->next;
142 Curl_safefree(item->data);
143 free(item);
144 item = next;
145 } while(next);
146}
147