xref: /curl/lib/strdup.c (revision 7c992dd9)
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 #ifdef _WIN32
30 #include <wchar.h>
31 #endif
32 
33 #include "strdup.h"
34 #include "curl_memory.h"
35 
36 /* The last #include file should be: */
37 #include "memdebug.h"
38 
39 #ifndef HAVE_STRDUP
Curl_strdup(const char * str)40 char *Curl_strdup(const char *str)
41 {
42   size_t len;
43   char *newstr;
44 
45   if(!str)
46     return (char *)NULL;
47 
48   len = strlen(str) + 1;
49 
50   newstr = malloc(len);
51   if(!newstr)
52     return (char *)NULL;
53 
54   memcpy(newstr, str, len);
55   return newstr;
56 }
57 #endif
58 
59 #ifdef _WIN32
60 /***************************************************************************
61  *
62  * Curl_wcsdup(source)
63  *
64  * Copies the 'source' wchar string to a newly allocated buffer (that is
65  * returned).
66  *
67  * Returns the new pointer or NULL on failure.
68  *
69  ***************************************************************************/
Curl_wcsdup(const wchar_t * src)70 wchar_t *Curl_wcsdup(const wchar_t *src)
71 {
72   size_t length = wcslen(src);
73 
74   if(length > (SIZE_T_MAX / sizeof(wchar_t)) - 1)
75     return (wchar_t *)NULL; /* integer overflow */
76 
77   return (wchar_t *)Curl_memdup(src, (length + 1) * sizeof(wchar_t));
78 }
79 #endif
80 
81 /***************************************************************************
82  *
83  * Curl_memdup(source, length)
84  *
85  * Copies the 'source' data to a newly allocated buffer (that is
86  * returned). Copies 'length' bytes.
87  *
88  * Returns the new pointer or NULL on failure.
89  *
90  ***************************************************************************/
Curl_memdup(const void * src,size_t length)91 void *Curl_memdup(const void *src, size_t length)
92 {
93   void *buffer = malloc(length);
94   if(!buffer)
95     return NULL; /* fail */
96 
97   memcpy(buffer, src, length);
98 
99   return buffer;
100 }
101 
102 /***************************************************************************
103  *
104  * Curl_memdup0(source, length)
105  *
106  * Copies the 'source' string to a newly allocated buffer (that is returned).
107  * Copies 'length' bytes then adds a null terminator.
108  *
109  * Returns the new pointer or NULL on failure.
110  *
111  ***************************************************************************/
Curl_memdup0(const char * src,size_t length)112 void *Curl_memdup0(const char *src, size_t length)
113 {
114   char *buf = malloc(length + 1);
115   if(!buf)
116     return NULL;
117   memcpy(buf, src, length);
118   buf[length] = 0;
119   return buf;
120 }
121 
122 /***************************************************************************
123  *
124  * Curl_saferealloc(ptr, size)
125  *
126  * Does a normal realloc(), but will free the data pointer if the realloc
127  * fails. If 'size' is non-zero, it will free the data and return a failure.
128  *
129  * This convenience function is provided and used to help us avoid a common
130  * mistake pattern when we could pass in a zero, catch the NULL return and end
131  * up free'ing the memory twice.
132  *
133  * Returns the new pointer or NULL on failure.
134  *
135  ***************************************************************************/
Curl_saferealloc(void * ptr,size_t size)136 void *Curl_saferealloc(void *ptr, size_t size)
137 {
138   void *datap = realloc(ptr, size);
139   if(size && !datap)
140     /* only free 'ptr' if size was non-zero */
141     free(ptr);
142   return datap;
143 }
144