1 | /* Bug 18125: Verify setcontext calls exit() and not _exit(). |
2 | Copyright (C) 2015-2022 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <errno.h> |
20 | #include <signal.h> |
21 | #include <stdio.h> |
22 | #include <stdlib.h> |
23 | #include <string.h> |
24 | #include <ucontext.h> |
25 | #include <unistd.h> |
26 | #include <limits.h> |
27 | #include <sys/types.h> |
28 | #include <sys/stat.h> |
29 | #include <fcntl.h> |
30 | |
31 | /* Please note that depending on the outcome of Bug 18135 this test |
32 | may become invalid, and instead of testing for calling exit it |
33 | should be reworked to test for the last context calling |
34 | pthread_exit(). */ |
35 | |
36 | static ucontext_t ctx; |
37 | static char *filename; |
38 | |
39 | /* It is intended that this function does nothing. */ |
40 | static void |
41 | cf (void) |
42 | { |
43 | printf (format: "called context function\n" ); |
44 | } |
45 | |
46 | static void |
47 | exit_called (void) |
48 | { |
49 | int fd; |
50 | ssize_t res; |
51 | const char buf[] = "Called exit function\n" ; |
52 | |
53 | fd = open (file: filename, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR); |
54 | if (fd == -1) |
55 | { |
56 | printf (format: "FAIL: Unable to create test file %s\n" , filename); |
57 | exit (1); |
58 | } |
59 | res = write (fd, buf, sizeof (buf)); |
60 | if (res != sizeof (buf)) |
61 | { |
62 | printf (format: "FAIL: Expected to write test file in one write call.\n" ); |
63 | exit (1); |
64 | } |
65 | res = close (fd: fd); |
66 | if (res == -1) |
67 | { |
68 | printf (format: "FAIL: Failed to close test file.\n" ); |
69 | exit (1); |
70 | } |
71 | printf (format: "PASS: %s" , buf); |
72 | } |
73 | |
74 | /* The test expects a filename given by the wrapper calling script. |
75 | The test then registers an atexit handler that will create the |
76 | file to indicate that the atexit handler ran. Then the test |
77 | creates a context, modifies it with makecontext, and sets it. |
78 | The context has only a single context which then must exit. |
79 | If it incorrectly exits via _exit then the atexit handler is |
80 | not run, the file is not created, and the wrapper detects this |
81 | and fails the test. This test cannot be done using an _exit |
82 | interposer since setcontext avoids the PLT and calls _exit |
83 | directly. */ |
84 | static int |
85 | do_test (int argc, char **argv) |
86 | { |
87 | int ret; |
88 | char st1[32768]; |
89 | ucontext_t tempctx = ctx; |
90 | |
91 | if (argc < 2) |
92 | { |
93 | printf (format: "FAIL: Test missing filename argument.\n" ); |
94 | exit (1); |
95 | } |
96 | |
97 | filename = argv[1]; |
98 | |
99 | atexit (func: exit_called); |
100 | |
101 | puts (s: "making contexts" ); |
102 | if (getcontext (ucp: &ctx) != 0) |
103 | { |
104 | if (errno == ENOSYS) |
105 | { |
106 | /* Exit with 77 to mark the test as UNSUPPORTED. */ |
107 | printf (format: "UNSUPPORTED: getcontext not implemented.\n" ); |
108 | exit (77); |
109 | } |
110 | |
111 | printf (format: "FAIL: getcontext failed.\n" ); |
112 | exit (1); |
113 | } |
114 | |
115 | ctx.uc_stack.ss_sp = st1; |
116 | ctx.uc_stack.ss_size = sizeof (st1); |
117 | ctx.uc_link = 0; |
118 | makecontext (ucp: &ctx, func: cf, argc: 0); |
119 | |
120 | /* Without this check, a stub makecontext can make us spin forever. */ |
121 | if (memcmp (&tempctx, &ctx, sizeof ctx) == 0) |
122 | { |
123 | puts (s: "UNSUPPORTED: makecontext was a no-op, presuming not implemented" ); |
124 | exit (77); |
125 | } |
126 | |
127 | ret = setcontext (&ctx); |
128 | if (ret != 0) |
129 | { |
130 | printf (format: "FAIL: setcontext returned with %d and errno of %d.\n" , ret, errno); |
131 | exit (1); |
132 | } |
133 | |
134 | printf (format: "FAIL: Impossibly returned to main.\n" ); |
135 | exit (1); |
136 | } |
137 | |
138 | #include "../test-skeleton.c" |
139 | |