1 /* Test POSIX lock on an open file (lockf).
2    Copyright (C) 2019-2022 Free Software Foundation, Inc.
3 
4    This program is free software; you can redistribute it and/or
5    modify it under the terms of the GNU General Public License
6    as published by the Free Software Foundation; either version 2
7    of the License, or (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
15    along with this program; if not, see <https://www.gnu.org/licenses/>.
16 */
17 
18 #include <unistd.h>
19 #include <stdint.h>
20 #include <errno.h>
21 #include <stdio.h>
22 
23 #include <support/temp_file.h>
24 #include <support/capture_subprocess.h>
25 #include <support/check.h>
26 
27 static char *temp_filename;
28 static int temp_fd;
29 
30 static void
do_prepare(int argc,char ** argv)31 do_prepare (int argc, char **argv)
32 {
33   temp_fd = create_temp_file ("tst-lockfd.", &temp_filename);
34   TEST_VERIFY_EXIT (temp_fd != -1);
35 }
36 #define PREPARE do_prepare
37 
38 static void
do_test_child_lockf(void * closure)39 do_test_child_lockf (void *closure)
40 {
41   /* Check if parent has [0, 1024) locked.  */
42   TEST_COMPARE (lseek (temp_fd, 0, SEEK_SET), 0);
43   TEST_COMPARE (lockf (temp_fd, F_TLOCK, 1024), -1);
44   TEST_COMPARE (errno, EAGAIN);
45   TEST_COMPARE (lockf (temp_fd, F_TEST, 1024), -1);
46   TEST_COMPARE (errno, EACCES);
47   /* Also Check if parent has last 1024 bytes locked.  */
48   TEST_COMPARE (lseek (temp_fd, INT32_MAX-1024, SEEK_SET), INT32_MAX-1024);
49   TEST_COMPARE (lockf (temp_fd, F_TEST, 1024), -1);
50 
51   /* And try to lock [1024, 2048).  */
52   TEST_COMPARE (lseek (temp_fd, 1024, SEEK_SET), 1024);
53   TEST_COMPARE (lockf (temp_fd, F_LOCK, 1024), 0);
54 
55   /* Check if non-LFS interface cap access to 32-bif off_t.  */
56   TEST_COMPARE (lseek64 (temp_fd, (off64_t)INT32_MAX, SEEK_SET),
57 		(off64_t)INT32_MAX);
58   TEST_COMPARE (lockf64 (temp_fd, F_TEST, 1024), 0);
59 }
60 
61 static void
do_test_child_lockf64(void * closure)62 do_test_child_lockf64 (void *closure)
63 {
64   /* Check if parent has [0, 1024) locked.  */
65   TEST_COMPARE (lseek64 (temp_fd, 0, SEEK_SET), 0);
66   TEST_COMPARE (lockf64 (temp_fd, F_TLOCK, 1024), -1);
67   TEST_COMPARE (errno, EAGAIN);
68   TEST_COMPARE (lockf64 (temp_fd, F_TEST, 1024), -1);
69   TEST_COMPARE (errno, EACCES);
70   /* Also Check if parent has last 1024 bytes locked.  */
71   TEST_COMPARE (lseek64 (temp_fd, INT32_MAX-1024, SEEK_SET), INT32_MAX-1024);
72   TEST_COMPARE (lockf64 (temp_fd, F_TEST, 1024), -1);
73 
74   /* And try to lock [1024, 2048).  */
75   TEST_COMPARE (lseek64 (temp_fd, 1024, SEEK_SET), 1024);
76   TEST_COMPARE (lockf64 (temp_fd, F_LOCK, 1024), 0);
77 
78   /* And also [INT32_MAX, INT32_MAX+1024).  */
79   {
80     off64_t off = (off64_t)INT32_MAX;
81     TEST_COMPARE (lseek64 (temp_fd, off, SEEK_SET), off);
82     TEST_COMPARE (lockf64 (temp_fd, F_LOCK, 1024), 0);
83   }
84 
85   /* Check if [INT32_MAX+1024, INT64_MAX) is locked.  */
86   {
87     off64_t off = (off64_t)INT32_MAX+1024;
88     TEST_COMPARE (lseek64 (temp_fd, off, SEEK_SET), off);
89     TEST_COMPARE (lockf64 (temp_fd, F_TLOCK, 1024), -1);
90     TEST_COMPARE (errno, EAGAIN);
91     TEST_COMPARE (lockf64 (temp_fd, F_TEST, 1024), -1);
92     TEST_COMPARE (errno, EACCES);
93   }
94 }
95 
96 static int
do_test(void)97 do_test (void)
98 {
99   /* Basic tests to check if a lock can be obtained and checked.  */
100   TEST_COMPARE (lockf (temp_fd, F_LOCK, 1024), 0);
101   TEST_COMPARE (lockf (temp_fd, F_LOCK, INT32_MAX), 0);
102   TEST_COMPARE (lockf (temp_fd, F_TLOCK, 1024), 0);
103   TEST_COMPARE (lockf (temp_fd, F_TEST, 1024), 0);
104   TEST_COMPARE (lseek (temp_fd, 1024, SEEK_SET), 1024);
105   TEST_COMPARE (lockf (temp_fd, F_ULOCK, 1024), 0);
106   /* Parent process should have ([0, 1024), [2048, INT32_MAX)) ranges locked.  */
107 
108   {
109     struct support_capture_subprocess result;
110     result = support_capture_subprocess (do_test_child_lockf, NULL);
111     support_capture_subprocess_check (&result, "lockf", 0, sc_allow_none);
112   }
113 
114   if (sizeof (off_t) != sizeof (off64_t))
115     {
116       /* Check if previously locked regions with LFS symbol.  */
117       TEST_COMPARE (lseek (temp_fd, 0, SEEK_SET), 0);
118       TEST_COMPARE (lockf64 (temp_fd, F_LOCK, 1024), 0);
119       TEST_COMPARE (lockf64 (temp_fd, F_TLOCK, 1024), 0);
120       TEST_COMPARE (lockf64 (temp_fd, F_TEST, 1024), 0);
121       /* Lock region [INT32_MAX+1024, INT64_MAX).  */
122       off64_t off = (off64_t)INT32_MAX + 1024;
123       TEST_COMPARE (lseek64 (temp_fd, off, SEEK_SET), off);
124       TEST_COMPARE (lockf64 (temp_fd, F_LOCK, 1024), 0);
125       /* Parent process should have ([0, 1024), [2048, INT32_MAX),
126 	 [INT32_MAX+1024, INT64_MAX)) ranges locked.  */
127 
128       {
129 	struct support_capture_subprocess result;
130 	result = support_capture_subprocess (do_test_child_lockf64, NULL);
131 	support_capture_subprocess_check (&result, "lockf", 0, sc_allow_none);
132       }
133     }
134 
135   return 0;
136 }
137 
138 #include <support/test-driver.c>
139