1 /* -*- mode: c; c-file-style: "bsd"; indent-tabs-mode: t -*- */
2 /*
3 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 /* Provide strlcpy and strlcat for platforms that don't have them. */
19
20 #include "k5-platform.h"
21 #include <sys/types.h>
22 #include <string.h>
23
24 /*
25 * Copy src to string dst of size siz. At most siz-1 characters
26 * will be copied. Always NUL terminates (unless siz == 0).
27 * Returns strlen(src); if retval >= siz, truncation occurred.
28 */
29 size_t
krb5int_strlcpy(char * dst,const char * src,size_t siz)30 krb5int_strlcpy(char *dst, const char *src, size_t siz)
31 {
32 char *d = dst;
33 const char *s = src;
34 size_t n = siz;
35
36 /* Copy as many bytes as will fit */
37 if (n != 0) {
38 while (--n != 0) {
39 if ((*d++ = *s++) == '\0')
40 break;
41 }
42 }
43
44 /* Not enough room in dst, add NUL and traverse rest of src */
45 if (n == 0) {
46 if (siz != 0)
47 *d = '\0'; /* NUL-terminate dst */
48 while (*s++)
49 ;
50 }
51
52 return(s - src - 1); /* count does not include NUL */
53 }
54
55 /*
56 * Appends src to string dst of size siz (unlike strncat, siz is the
57 * full size of dst, not space left). At most siz-1 characters
58 * will be copied. Always NUL terminates (unless siz <= strlen(dst)).
59 * Returns strlen(src) + MIN(siz, strlen(initial dst)).
60 * If retval >= siz, truncation occurred.
61 */
62 size_t
krb5int_strlcat(char * dst,const char * src,size_t siz)63 krb5int_strlcat(char *dst, const char *src, size_t siz)
64 {
65 char *d = dst;
66 const char *s = src;
67 size_t n = siz;
68 size_t dlen;
69
70 /* Find the end of dst and adjust bytes left but don't go past end */
71 while (n-- != 0 && *d != '\0')
72 d++;
73 dlen = d - dst;
74 n = siz - dlen;
75
76 if (n == 0)
77 return(dlen + strlen(s));
78 while (*s != '\0') {
79 if (n != 1) {
80 *d++ = *s;
81 n--;
82 }
83 s++;
84 }
85 *d = '\0';
86
87 return(dlen + (s - src)); /* count does not include NUL */
88 }
89