1/******************************************************************************
2 *
3 *  Copyright 2015 Google, Inc.
4 *
5 *  Licensed under the Apache License, Version 2.0 (the "License");
6 *  you may not use this file except in compliance with the License.
7 *  You may obtain a copy of the License at:
8 *
9 *  http://www.apache.org/licenses/LICENSE-2.0
10 *
11 *  Unless required by applicable law or agreed to in writing, software
12 *  distributed under the License is distributed on an "AS IS" BASIS,
13 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 *  See the License for the specific language governing permissions and
15 *  limitations under the License.
16 *
17 ******************************************************************************/
18
19/************************************************************************************
20 *
21 *  Filename:      compat.c
22 *
23 *  Description:   Compatibility functions for non-bionic C libraries
24 *
25 *
26 ***********************************************************************************/
27
28#include <features.h>
29#include <string.h>
30#include <sys/syscall.h>
31#include <sys/types.h>
32#include <unistd.h>
33#include "osi/include/compat.h"
34
35#if __GLIBC__
36pid_t
37gettid(void)
38{
39  return syscall(SYS_gettid);
40}
41#endif
42
43/* These functions from bionic
44 *
45 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
46 *
47 * Permission to use, copy, modify, and distribute this software for any
48 * purpose with or without fee is hereby granted, provided that the above
49 * copyright notice and this permission notice appear in all copies.
50 *
51 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
52 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
53 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
54 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
55 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
56 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
57 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
58 */
59
60#if __GLIBC__
61/*
62 * Copy src to string dst of size siz.  At most siz-1 characters
63 * will be copied.  Always NUL terminates (unless siz == 0).
64 * Returns strlen(src); if retval >= siz, truncation occurred.
65 */
66size_t
67strlcpy(char *dst, const char *src, size_t siz)
68{
69  char *d = dst;
70  const char *s = src;
71  size_t n = siz;
72
73  /* Copy as many bytes as will fit */
74  if (n != 0) {
75    while (--n != 0) {
76      if ((*d++ = *s++) == '\0')
77        break;
78    }
79  }
80
81  /* Not enough room in dst, add NUL and traverse rest of src */
82  if (n == 0) {
83    if (siz != 0)
84      *d = '\0'; /* NUL-terminate dst */
85    while (*s++)
86      ;
87  }
88
89  return(s - src - 1); /* count does not include NUL */
90}
91#endif
92
93#if __GLIBC__
94/*
95 * Appends src to string dst of size siz (unlike strncat, siz is the
96 * full size of dst, not space left).  At most siz-1 characters
97 * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
98 * Returns strlen(src) + MIN(siz, strlen(initial dst)).
99 * If retval >= siz, truncation occurred.
100 */
101size_t
102strlcat(char *dst, const char *src, size_t siz)
103{
104  char *d = dst;
105  const char *s = src;
106  size_t n = siz;
107  size_t dlen;
108
109  /* Find the end of dst and adjust bytes left but don't go past end */
110  while (n-- != 0 && *d != '\0')
111    d++;
112  dlen = d - dst;
113  n = siz - dlen;
114
115  if (n == 0)
116    return (dlen + strlen(s));
117
118  while (*s != '\0') {
119    if (n != 1) {
120      *d++ = *s;
121      n--;
122    }
123
124    s++;
125  }
126
127  *d = '\0';
128
129  return (dlen + (s - src)); /* count does not include NUL */
130}
131#endif
132