1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
* Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
*/
/*
* getcwd() returns the pathname of the current working directory.
* On error, a NULL pointer is returned and errno is set.
*/
#pragma weak _getcwd = getcwd
#include "lint.h"
#include <sys/param.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
char *
getcwd(char *pathname, size_t size)
{
int alloc = 0;
if (size == 0 && pathname == NULL) {
/*
* If no size was provided, start with a buffer that should
* accommodate any normal path and, if it is not big enough,
* keep doubling it to try and make enough space.
*
* Any non-global zone path is longer when observed from the
* global zone, and some filesystems, including ZFS, support
* paths much longer than MAXPATHLEN/_PC_PATH_MAX.
*
* To protect against unbounded memory usage, cap to 128KiB.
* This is an arbitrary limit which is far bigger than the
* length of any practical path on the system.
*/
if ((size = pathconf(".", _PC_PATH_MAX)) == -1)
size = MAXPATHLEN;
while (size <= 0x20000) {
if ((pathname = reallocf(pathname, size)) == NULL) {
errno = ENOMEM;
return (NULL);
}
if (syscall(SYS_getcwd, pathname, size) == 0) {
char *ret;
/*
* Shrink the buffer to the length actually
* required to hold the final path.
*/
ret = realloc(pathname, strlen(pathname) + 1);
if (ret == NULL)
return (pathname);
return (ret);
}
if (errno != ERANGE)
break;
size <<= 1;
}
free(pathname);
return (NULL);
}
if (size == 0) {
errno = EINVAL;
return (NULL);
}
if (pathname == NULL) {
if ((pathname = malloc(size)) == NULL) {
errno = ENOMEM;
return (NULL);
}
alloc = 1;
}
if (syscall(SYS_getcwd, pathname, size) == 0)
return (pathname);
if (alloc)
free(pathname);
return (NULL);
}
|
