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.cc
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 
34 #include "osi/include/compat.h"
35 #include "osi/include/osi.h"
36 
37 #if __GLIBC__
gettid(void)38 pid_t gettid(void) { return syscall(SYS_gettid); }
39 #endif
40 
41 /* These functions from bionic
42  *
43  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
44  *
45  * Permission to use, copy, modify, and distribute this software for any
46  * purpose with or without fee is hereby granted, provided that the above
47  * copyright notice and this permission notice appear in all copies.
48  *
49  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
50  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
51  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
52  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
53  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
54  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
55  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
56  */
57 
58 #if __GLIBC__
59 /*
60  * Copy src to string dst of size siz.  At most siz-1 characters
61  * will be copied.  Always NUL terminates (unless siz == 0).
62  * Returns strlen(src); if retval >= siz, truncation occurred.
63  */
strlcpy(char * dst,const char * src,size_t siz)64 size_t strlcpy(char* dst, const char* src, size_t siz) {
65   char* d = dst;
66   const char* s = src;
67   size_t n = siz;
68 
69   /* Copy as many bytes as will fit */
70   if (n != 0) {
71     while (--n != 0) {
72       if ((*d++ = *s++) == '\0') break;
73     }
74   }
75 
76   /* Not enough room in dst, add NUL and traverse rest of src */
77   if (n == 0) {
78     if (siz != 0) *d = '\0'; /* NUL-terminate dst */
79     while (*s++)
80       ;
81   }
82 
83   return (s - src - 1); /* count does not include NUL */
84 }
85 #endif
86 
87 #if __GLIBC__
88 /*
89  * Appends src to string dst of size siz (unlike strncat, siz is the
90  * full size of dst, not space left).  At most siz-1 characters
91  * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
92  * Returns strlen(src) + MIN(siz, strlen(initial dst)).
93  * If retval >= siz, truncation occurred.
94  */
strlcat(char * dst,const char * src,size_t siz)95 size_t strlcat(char* dst, const char* src, size_t siz) {
96   char* d = dst;
97   const char* s = src;
98   size_t n = siz;
99   size_t dlen;
100 
101   /* Find the end of dst and adjust bytes left but don't go past end */
102   while (n-- != 0 && *d != '\0') d++;
103   dlen = d - dst;
104   n = siz - dlen;
105 
106   if (n == 0) return (dlen + strlen(s));
107 
108   while (*s != '\0') {
109     if (n != 1) {
110       *d++ = *s;
111       n--;
112     }
113 
114     s++;
115   }
116 
117   *d = '\0';
118 
119   return (dlen + (s - src)); /* count does not include NUL */
120 }
121 #endif
122