1 | /* Test backtrace and backtrace_symbols for signal frames, where a |
2 | system call was interrupted by a signal. |
3 | Copyright (C) 2011-2022 Free Software Foundation, Inc. |
4 | This file is part of the GNU C Library. |
5 | |
6 | The GNU C Library is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Lesser General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2.1 of the License, or (at your option) any later version. |
10 | |
11 | The GNU C Library is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | Lesser General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU Lesser General Public |
17 | License along with the GNU C Library; if not, see |
18 | <https://www.gnu.org/licenses/>. */ |
19 | |
20 | #include <execinfo.h> |
21 | #include <search.h> |
22 | #include <stdio.h> |
23 | #include <stdlib.h> |
24 | #include <string.h> |
25 | #include <sys/types.h> |
26 | #include <signal.h> |
27 | #include <unistd.h> |
28 | |
29 | #include "tst-backtrace.h" |
30 | |
31 | #ifndef SIGACTION_FLAGS |
32 | # define SIGACTION_FLAGS 0 |
33 | #endif |
34 | |
35 | /* The backtrace should include at least handle_signal, a signal |
36 | trampoline, read, 3 * fn, and do_test. */ |
37 | #define NUM_FUNCTIONS 7 |
38 | |
39 | void |
40 | handle_signal (int signum) |
41 | { |
42 | void *addresses[NUM_FUNCTIONS]; |
43 | char **symbols; |
44 | int n; |
45 | int i; |
46 | |
47 | /* Get the backtrace addresses. */ |
48 | n = backtrace (array: addresses, size: sizeof (addresses) / sizeof (addresses[0])); |
49 | printf (format: "Obtained backtrace with %d functions\n" , n); |
50 | /* Check that there are at least seven functions. */ |
51 | if (n < NUM_FUNCTIONS) |
52 | { |
53 | FAIL (); |
54 | return; |
55 | } |
56 | /* Convert them to symbols. */ |
57 | symbols = backtrace_symbols (array: addresses, size: n); |
58 | /* Check that symbols were obtained. */ |
59 | if (symbols == NULL) |
60 | { |
61 | FAIL (); |
62 | return; |
63 | } |
64 | for (i = 0; i < n; ++i) |
65 | printf (format: "Function %d: %s\n" , i, symbols[i]); |
66 | /* Check that the function names obtained are accurate. */ |
67 | if (!match (sym: symbols[0], name: "handle_signal" )) |
68 | { |
69 | FAIL (); |
70 | return; |
71 | } |
72 | |
73 | /* Do not check name for signal trampoline or cancellable syscall |
74 | wrappers (__syscall_cancel*). */ |
75 | for (; i < n - 1; i++) |
76 | if (match (sym: symbols[i], name: "read" )) |
77 | break; |
78 | if (i == n - 1) |
79 | { |
80 | FAIL (); |
81 | return; |
82 | } |
83 | |
84 | for (; i < n - 1; i++) |
85 | if (!match (sym: symbols[i], name: "fn" )) |
86 | { |
87 | FAIL (); |
88 | return; |
89 | } |
90 | /* Symbol names are not available for static functions, so we do not |
91 | check do_test. */ |
92 | |
93 | /* Check that backtrace does not return more than what fits in the array |
94 | (bug 25423). */ |
95 | for (int j = 0; j < NUM_FUNCTIONS; j++) |
96 | { |
97 | n = backtrace (array: addresses, size: j); |
98 | if (n > j) |
99 | { |
100 | FAIL (); |
101 | return; |
102 | } |
103 | } |
104 | } |
105 | |
106 | NO_INLINE int |
107 | fn (int c, int flags) |
108 | { |
109 | pid_t parent_pid, child_pid; |
110 | int pipefd[2]; |
111 | char r[1]; |
112 | struct sigaction act; |
113 | |
114 | if (c > 0) |
115 | { |
116 | fn (c: c - 1, flags); |
117 | return x; |
118 | } |
119 | |
120 | memset (&act, 0, sizeof (act)); |
121 | act.sa_handler = handle_signal; |
122 | act.sa_flags = flags; |
123 | sigemptyset (&act.sa_mask); |
124 | sigaction (SIGUSR1, act: &act, NULL); |
125 | parent_pid = getpid (); |
126 | if (pipe (pipedes: pipefd) == -1) |
127 | abort (); |
128 | |
129 | child_pid = fork (); |
130 | if (child_pid == (pid_t) -1) |
131 | abort (); |
132 | else if (child_pid == 0) |
133 | { |
134 | sleep (seconds: 1); |
135 | kill (pid: parent_pid, SIGUSR1); |
136 | _exit (0); |
137 | } |
138 | |
139 | /* In the parent. */ |
140 | read (pipefd[0], r, 1); |
141 | |
142 | return 0; |
143 | } |
144 | |
145 | NO_INLINE int |
146 | do_test (void) |
147 | { |
148 | fn (c: 2, SIGACTION_FLAGS); |
149 | return ret; |
150 | } |
151 | |
152 | #include <support/test-driver.c> |
153 | |