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5e8754f9 | 1 | # serial 7 |
6ec2e0f5 SDJ |
2 | # Determine whether getcwd aborts when the length of the working directory |
3 | # name is unusually large. Any length between 4k and 16k trigger the bug | |
4 | # when using glibc-2.4.90-9 or older. | |
5 | ||
5e8754f9 | 6 | # Copyright (C) 2006, 2009-2016 Free Software Foundation, Inc. |
6ec2e0f5 SDJ |
7 | # This file is free software; the Free Software Foundation |
8 | # gives unlimited permission to copy and/or distribute it, | |
9 | # with or without modifications, as long as this notice is preserved. | |
10 | ||
11 | # From Jim Meyering | |
12 | ||
13 | # gl_FUNC_GETCWD_ABORT_BUG([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) | |
14 | AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG], | |
15 | [ | |
16 | AC_CHECK_DECLS_ONCE([getcwd]) | |
17 | AC_CHECK_HEADERS_ONCE([unistd.h]) | |
18 | AC_REQUIRE([gl_PATHMAX_SNIPPET_PREREQ]) | |
5e8754f9 | 19 | AC_CHECK_FUNCS([getpagesize]) |
6ec2e0f5 | 20 | AC_CACHE_CHECK([whether getcwd aborts when 4k < cwd_length < 16k], |
5e8754f9 | 21 | gl_cv_func_getcwd_abort_bug, |
6ec2e0f5 SDJ |
22 | [# Remove any remnants of a previous test. |
23 | rm -rf confdir-14B--- | |
24 | # Arrange for deletion of the temporary directory this test creates. | |
25 | ac_clean_files="$ac_clean_files confdir-14B---" | |
26 | dnl Please keep this in sync with tests/test-getcwd.c. | |
27 | AC_RUN_IFELSE( | |
28 | [AC_LANG_SOURCE( | |
29 | [[ | |
30 | #include <errno.h> | |
31 | #include <stdlib.h> | |
32 | #if HAVE_UNISTD_H | |
33 | # include <unistd.h> | |
34 | #else /* on Windows with MSVC */ | |
35 | # include <direct.h> | |
36 | #endif | |
37 | #include <string.h> | |
38 | #include <sys/stat.h> | |
39 | ||
40 | ]gl_PATHMAX_SNIPPET[ | |
41 | ||
42 | /* Don't get link errors because mkdir is redefined to rpl_mkdir. */ | |
43 | #undef mkdir | |
44 | ||
45 | #ifndef S_IRWXU | |
46 | # define S_IRWXU 0700 | |
47 | #endif | |
48 | ||
49 | /* FIXME: skip the run-test altogether on systems without getpagesize. */ | |
50 | #if ! HAVE_GETPAGESIZE | |
51 | # define getpagesize() 0 | |
52 | #endif | |
53 | ||
54 | /* This size is chosen to be larger than PATH_MAX (4k), yet smaller than | |
55 | the 16kB pagesize on ia64 linux. Those conditions make the code below | |
56 | trigger a bug in glibc's getcwd implementation before 2.4.90-10. */ | |
57 | #define TARGET_LEN (5 * 1024) | |
58 | ||
59 | int | |
60 | main () | |
61 | { | |
62 | char *cwd; | |
63 | size_t initial_cwd_len; | |
64 | int fail = 0; | |
65 | ||
66 | /* The bug is triggered when PATH_MAX < getpagesize (), so skip | |
67 | this relatively expensive and invasive test if that's not true. */ | |
68 | #ifdef PATH_MAX | |
69 | int bug_possible = PATH_MAX < getpagesize (); | |
70 | #else | |
71 | int bug_possible = 0; | |
72 | #endif | |
73 | if (! bug_possible) | |
74 | return 0; | |
75 | ||
76 | cwd = getcwd (NULL, 0); | |
77 | if (cwd == NULL) | |
78 | return 2; | |
79 | ||
80 | initial_cwd_len = strlen (cwd); | |
81 | free (cwd); | |
82 | ||
83 | if (1) | |
84 | { | |
85 | static char const dir_name[] = "confdir-14B---"; | |
86 | size_t desired_depth = ((TARGET_LEN - 1 - initial_cwd_len) | |
87 | / sizeof dir_name); | |
88 | size_t d; | |
89 | for (d = 0; d < desired_depth; d++) | |
90 | { | |
91 | if (mkdir (dir_name, S_IRWXU) < 0 || chdir (dir_name) < 0) | |
92 | { | |
93 | if (! (errno == ERANGE || errno == ENAMETOOLONG | |
94 | || errno == ENOENT)) | |
95 | fail = 3; /* Unable to construct deep hierarchy. */ | |
96 | break; | |
97 | } | |
98 | } | |
99 | ||
100 | /* If libc has the bug in question, this invocation of getcwd | |
101 | results in a failed assertion. */ | |
102 | cwd = getcwd (NULL, 0); | |
103 | if (cwd == NULL) | |
104 | fail = 4; /* getcwd didn't assert, but it failed for a long name | |
105 | where the answer could have been learned. */ | |
106 | free (cwd); | |
107 | ||
108 | /* Call rmdir first, in case the above chdir failed. */ | |
109 | rmdir (dir_name); | |
110 | while (0 < d--) | |
111 | { | |
112 | if (chdir ("..") < 0) | |
113 | { | |
114 | fail = 5; | |
115 | break; | |
116 | } | |
117 | rmdir (dir_name); | |
118 | } | |
119 | } | |
120 | ||
121 | return fail; | |
122 | } | |
123 | ]])], | |
5e8754f9 SDJ |
124 | [gl_cv_func_getcwd_abort_bug=no], |
125 | [dnl An abort will provoke an exit code of something like 134 (128 + 6). | |
126 | dnl An exit code of 4 can also occur (in OpenBSD 4.9, NetBSD 5.1 for | |
127 | dnl example): getcwd (NULL, 0) fails rather than returning a string | |
128 | dnl longer than PATH_MAX. This may be POSIX compliant (in some | |
129 | dnl interpretations of POSIX). But gnulib's getcwd module wants to | |
130 | dnl provide a non-NULL value in this case. | |
131 | ret=$? | |
132 | if test $ret -ge 128 || test $ret = 4; then | |
133 | gl_cv_func_getcwd_abort_bug=yes | |
134 | else | |
135 | gl_cv_func_getcwd_abort_bug=no | |
136 | fi], | |
137 | [gl_cv_func_getcwd_abort_bug=yes]) | |
138 | ]) | |
6ec2e0f5 SDJ |
139 | AS_IF([test $gl_cv_func_getcwd_abort_bug = yes], [$1], [$2]) |
140 | ]) |