Commit | Line | Data |
---|---|---|
9c9d63b1 | 1 | /* Copyright (C) 2011-2021 Free Software Foundation, Inc. |
6ec2e0f5 SDJ |
2 | This file is part of gnulib. |
3 | ||
4 | This program is free software: you can redistribute it and/or modify | |
5 | it under the terms of the GNU General Public License as published by | |
6 | the Free Software Foundation; either version 3 of the License, or | |
7 | (at your option) any later version. | |
8 | ||
9 | This program is distributed in the hope that it will be useful, | |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | GNU General Public License for more details. | |
13 | ||
14 | You should have received a copy of the GNU General Public License | |
c0c3707f | 15 | along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
6ec2e0f5 SDJ |
16 | |
17 | #include <config.h> | |
18 | ||
19 | /* Specification */ | |
20 | #include <unistd.h> | |
21 | ||
22 | #include <errno.h> | |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
25 | ||
26 | #if GNULIB_GETCWD | |
27 | /* Favor GPL getcwd.c if both getcwd and getcwd-lgpl modules are in use. */ | |
28 | typedef int dummy; | |
29 | #else | |
30 | ||
31 | /* Get the name of the current working directory, and put it in SIZE | |
32 | bytes of BUF. Returns NULL if the directory couldn't be determined | |
33 | (perhaps because the absolute name was longer than PATH_MAX, or | |
34 | because of missing read/search permissions on parent directories) | |
35 | or SIZE was too small. If successful, returns BUF. If BUF is | |
36 | NULL, an array is allocated with 'malloc'; the array is SIZE bytes | |
37 | long, unless SIZE == 0, in which case it is as big as | |
38 | necessary. */ | |
39 | ||
40 | # undef getcwd | |
9c9d63b1 PM |
41 | # if defined _WIN32 && !defined __CYGWIN__ |
42 | # define getcwd _getcwd | |
43 | # endif | |
44 | ||
6ec2e0f5 SDJ |
45 | char * |
46 | rpl_getcwd (char *buf, size_t size) | |
47 | { | |
48 | char *ptr; | |
49 | char *result; | |
50 | ||
51 | /* Handle single size operations. */ | |
52 | if (buf) | |
53 | { | |
54 | if (!size) | |
55 | { | |
56 | errno = EINVAL; | |
57 | return NULL; | |
58 | } | |
59 | return getcwd (buf, size); | |
60 | } | |
61 | ||
62 | if (size) | |
63 | { | |
64 | buf = malloc (size); | |
65 | if (!buf) | |
66 | { | |
67 | errno = ENOMEM; | |
68 | return NULL; | |
69 | } | |
70 | result = getcwd (buf, size); | |
71 | if (!result) | |
72 | { | |
73 | int saved_errno = errno; | |
74 | free (buf); | |
75 | errno = saved_errno; | |
76 | } | |
77 | return result; | |
78 | } | |
79 | ||
80 | /* Flexible sizing requested. Avoid over-allocation for the common | |
81 | case of a name that fits within a 4k page, minus some space for | |
82 | local variables, to be sure we don't skip over a guard page. */ | |
83 | { | |
84 | char tmp[4032]; | |
85 | size = sizeof tmp; | |
86 | ptr = getcwd (tmp, size); | |
87 | if (ptr) | |
88 | { | |
89 | result = strdup (ptr); | |
90 | if (!result) | |
91 | errno = ENOMEM; | |
92 | return result; | |
93 | } | |
94 | if (errno != ERANGE) | |
95 | return NULL; | |
96 | } | |
97 | ||
98 | /* My what a large directory name we have. */ | |
99 | do | |
100 | { | |
101 | size <<= 1; | |
102 | ptr = realloc (buf, size); | |
103 | if (ptr == NULL) | |
104 | { | |
105 | free (buf); | |
106 | errno = ENOMEM; | |
107 | return NULL; | |
108 | } | |
109 | buf = ptr; | |
110 | result = getcwd (buf, size); | |
111 | } | |
112 | while (!result && errno == ERANGE); | |
113 | ||
114 | if (!result) | |
115 | { | |
116 | int saved_errno = errno; | |
117 | free (buf); | |
118 | errno = saved_errno; | |
119 | } | |
120 | else | |
121 | { | |
c0c3707f CB |
122 | /* Here result == buf. */ |
123 | /* Shrink result before returning it. */ | |
124 | size_t actual_size = strlen (result) + 1; | |
125 | if (actual_size < size) | |
126 | { | |
127 | char *shrinked_result = realloc (result, actual_size); | |
128 | if (shrinked_result != NULL) | |
129 | result = shrinked_result; | |
130 | } | |
6ec2e0f5 SDJ |
131 | } |
132 | return result; | |
133 | } | |
134 | ||
135 | #endif |