1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel (at) 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.haxx.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 ***************************************************************************/ 22 23 #include "curl_setup.h" 24 25 #include <curl/curl.h> 26 27 #include "slist.h" 28 29 /* The last #include files should be: */ 30 #include "curl_memory.h" 31 #include "memdebug.h" 32 33 /* returns last node in linked list */ 34 static struct curl_slist *slist_get_last(struct curl_slist *list) 35 { 36 struct curl_slist *item; 37 38 /* if caller passed us a NULL, return now */ 39 if(!list) 40 return NULL; 41 42 /* loop through to find the last item */ 43 item = list; 44 while(item->next) { 45 item = item->next; 46 } 47 return item; 48 } 49 50 /* 51 * Curl_slist_append_nodup() appends a string to the linked list. Rather than 52 * copying the string in dynamic storage, it takes its ownership. The string 53 * should have been malloc()ated. Curl_slist_append_nodup always returns 54 * the address of the first record, so that you can use this function as an 55 * initialization function as well as an append function. 56 * If an error occurs, NULL is returned and the string argument is NOT 57 * released. 58 */ 59 struct curl_slist *Curl_slist_append_nodup(struct curl_slist *list, char *data) 60 { 61 struct curl_slist *last; 62 struct curl_slist *new_item; 63 64 DEBUGASSERT(data); 65 66 new_item = malloc(sizeof(struct curl_slist)); 67 if(!new_item) 68 return NULL; 69 70 new_item->next = NULL; 71 new_item->data = data; 72 73 /* if this is the first item, then new_item *is* the list */ 74 if(!list) 75 return new_item; 76 77 last = slist_get_last(list); 78 last->next = new_item; 79 return list; 80 } 81 82 /* 83 * curl_slist_append() appends a string to the linked list. It always returns 84 * the address of the first record, so that you can use this function as an 85 * initialization function as well as an append function. If you find this 86 * bothersome, then simply create a separate _init function and call it 87 * appropriately from within the program. 88 */ 89 struct curl_slist *curl_slist_append(struct curl_slist *list, 90 const char *data) 91 { 92 char *dupdata = strdup(data); 93 94 if(!dupdata) 95 return NULL; 96 97 list = Curl_slist_append_nodup(list, dupdata); 98 if(!list) 99 free(dupdata); 100 101 return list; 102 } 103 104 /* 105 * Curl_slist_duplicate() duplicates a linked list. It always returns the 106 * address of the first record of the cloned list or NULL in case of an 107 * error (or if the input list was NULL). 108 */ 109 struct curl_slist *Curl_slist_duplicate(struct curl_slist *inlist) 110 { 111 struct curl_slist *outlist = NULL; 112 struct curl_slist *tmp; 113 114 while(inlist) { 115 tmp = curl_slist_append(outlist, inlist->data); 116 117 if(!tmp) { 118 curl_slist_free_all(outlist); 119 return NULL; 120 } 121 122 outlist = tmp; 123 inlist = inlist->next; 124 } 125 return outlist; 126 } 127 128 /* be nice and clean up resources */ 129 void curl_slist_free_all(struct curl_slist *list) 130 { 131 struct curl_slist *next; 132 struct curl_slist *item; 133 134 if(!list) 135 return; 136 137 item = list; 138 do { 139 next = item->next; 140 Curl_safefree(item->data); 141 free(item); 142 item = next; 143 } while(next); 144 } 145