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 
34 #include "osi/include/compat.h"
35 #include "osi/include/osi.h"
36 
37 #if __GLIBC__
38 pid_t
gettid(void)39 gettid(void)
40 {
41   return syscall(SYS_gettid);
42 }
43 #endif
44 
45 /* These functions from bionic
46  *
47  * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
48  *
49  * Permission to use, copy, modify, and distribute this software for any
50  * purpose with or without fee is hereby granted, provided that the above
51  * copyright notice and this permission notice appear in all copies.
52  *
53  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
54  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
55  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
56  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
57  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
58  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
59  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
60  */
61 
62 #if __GLIBC__
63 /*
64  * Copy src to string dst of size siz.  At most siz-1 characters
65  * will be copied.  Always NUL terminates (unless siz == 0).
66  * Returns strlen(src); if retval >= siz, truncation occurred.
67  */
68 size_t
strlcpy(char * dst,const char * src,size_t siz)69 strlcpy(char *dst, const char *src, size_t siz)
70 {
71   char *d = dst;
72   const char *s = src;
73   size_t n = siz;
74 
75   /* Copy as many bytes as will fit */
76   if (n != 0) {
77     while (--n != 0) {
78       if ((*d++ = *s++) == '\0')
79         break;
80     }
81   }
82 
83   /* Not enough room in dst, add NUL and traverse rest of src */
84   if (n == 0) {
85     if (siz != 0)
86       *d = '\0'; /* NUL-terminate dst */
87     while (*s++)
88       ;
89   }
90 
91   return(s - src - 1); /* count does not include NUL */
92 }
93 #endif
94 
95 #if __GLIBC__
96 /*
97  * Appends src to string dst of size siz (unlike strncat, siz is the
98  * full size of dst, not space left).  At most siz-1 characters
99  * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
100  * Returns strlen(src) + MIN(siz, strlen(initial dst)).
101  * If retval >= siz, truncation occurred.
102  */
103 size_t
strlcat(char * dst,const char * src,size_t siz)104 strlcat(char *dst, const char *src, size_t siz)
105 {
106   char *d = dst;
107   const char *s = src;
108   size_t n = siz;
109   size_t dlen;
110 
111   /* Find the end of dst and adjust bytes left but don't go past end */
112   while (n-- != 0 && *d != '\0')
113     d++;
114   dlen = d - dst;
115   n = siz - dlen;
116 
117   if (n == 0)
118     return (dlen + strlen(s));
119 
120   while (*s != '\0') {
121     if (n != 1) {
122       *d++ = *s;
123       n--;
124     }
125 
126     s++;
127   }
128 
129   *d = '\0';
130 
131   return (dlen + (s - src)); /* count does not include NUL */
132 }
133 #endif
134