1// Copyright 2012 The Kyua Authors.
2// All rights reserved.
3//
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28
29#include "utils/signals/interrupts.hpp"
30
31extern "C" {
32#include <signal.h>
33#include <unistd.h>
34}
35
36#include <cstdlib>
37#include <iostream>
38
39#include <atf-c++.hpp>
40
41#include "utils/format/macros.hpp"
42#include "utils/fs/path.hpp"
43#include "utils/process/child.ipp"
44#include "utils/process/status.hpp"
45#include "utils/signals/exceptions.hpp"
46#include "utils/signals/programmer.hpp"
47
48namespace fs = utils::fs;
49namespace process = utils::process;
50namespace signals = utils::signals;
51
52
53namespace {
54
55
56/// Set to the signal that fired; -1 if none.
57static volatile int fired_signal = -1;
58
59
60/// Test handler for signals.
61///
62/// \post fired_signal is set to the signal that triggered the handler.
63///
64/// \param signo The signal that triggered the handler.
65static void
66signal_handler(const int signo)
67{
68    PRE(fired_signal == -1 || fired_signal == signo);
69    fired_signal = signo;
70}
71
72
73/// Child process that pauses waiting to be killed.
74static void
75pause_child(void)
76{
77    sigset_t mask;
78    sigemptyset(&mask);
79    // We loop waiting for signals because we want the parent process to send us
80    // a SIGKILL that we cannot handle, not just any non-deadly signal.
81    for (;;) {
82        std::cerr << F("Waiting for any signal; pid=%s\n") % ::getpid();
83        ::sigsuspend(&mask);
84        std::cerr << F("Signal received; pid=%s\n") % ::getpid();
85    }
86}
87
88
89/// Checks that interrupts_handler() handles a particular signal.
90///
91/// This indirectly checks the check_interrupt() function, which is not part of
92/// the class but is tightly related.
93///
94/// \param signo The signal to check.
95/// \param explicit_unprogram Whether to call interrupts_handler::unprogram()
96///     explicitly before letting the object go out of scope.
97static void
98check_interrupts_handler(const int signo, const bool explicit_unprogram)
99{
100    fired_signal = -1;
101
102    signals::programmer test_handler(signo, signal_handler);
103
104    {
105        signals::interrupts_handler interrupts;
106
107        // No pending interrupts at first.
108        signals::check_interrupt();
109
110        // Send us an interrupt and check for it.
111        ::kill(getpid(), signo);
112        ATF_REQUIRE_THROW_RE(signals::interrupted_error,
113                             F("Interrupted by signal %s") % signo,
114                             signals::check_interrupt());
115
116        // Interrupts should have been cleared now, so this should not throw.
117        signals::check_interrupt();
118
119        // Check to see if a second interrupt is detected.
120        ::kill(getpid(), signo);
121        ATF_REQUIRE_THROW_RE(signals::interrupted_error,
122                             F("Interrupted by signal %s") % signo,
123                             signals::check_interrupt());
124
125        // And ensure the interrupt was cleared again.
126        signals::check_interrupt();
127
128        if (explicit_unprogram) {
129            interrupts.unprogram();
130        }
131    }
132
133    ATF_REQUIRE_EQ(-1, fired_signal);
134    ::kill(getpid(), signo);
135    ATF_REQUIRE_EQ(signo, fired_signal);
136
137    test_handler.unprogram();
138}
139
140
141/// Checks that interrupts_inhibiter() handles a particular signal.
142///
143/// \param signo The signal to check.
144static void
145check_interrupts_inhibiter(const int signo)
146{
147    signals::programmer test_handler(signo, signal_handler);
148
149    {
150        signals::interrupts_inhibiter inhibiter;
151        {
152            signals::interrupts_inhibiter nested_inhibiter;
153            ::kill(::getpid(), signo);
154            ATF_REQUIRE_EQ(-1, fired_signal);
155        }
156        ::kill(::getpid(), signo);
157        ATF_REQUIRE_EQ(-1, fired_signal);
158    }
159    ATF_REQUIRE_EQ(signo, fired_signal);
160
161    test_handler.unprogram();
162}
163
164
165}  // anonymous namespace
166
167
168ATF_TEST_CASE_WITHOUT_HEAD(interrupts_handler__sighup);
169ATF_TEST_CASE_BODY(interrupts_handler__sighup)
170{
171    // We run this twice in sequence to ensure that we can actually program two
172    // interrupts handlers in a row.
173    check_interrupts_handler(SIGHUP, true);
174    check_interrupts_handler(SIGHUP, false);
175}
176
177
178ATF_TEST_CASE_WITHOUT_HEAD(interrupts_handler__sigint);
179ATF_TEST_CASE_BODY(interrupts_handler__sigint)
180{
181    // We run this twice in sequence to ensure that we can actually program two
182    // interrupts handlers in a row.
183    check_interrupts_handler(SIGINT, true);
184    check_interrupts_handler(SIGINT, false);
185}
186
187
188ATF_TEST_CASE_WITHOUT_HEAD(interrupts_handler__sigterm);
189ATF_TEST_CASE_BODY(interrupts_handler__sigterm)
190{
191    // We run this twice in sequence to ensure that we can actually program two
192    // interrupts handlers in a row.
193    check_interrupts_handler(SIGTERM, true);
194    check_interrupts_handler(SIGTERM, false);
195}
196
197
198ATF_TEST_CASE(interrupts_handler__kill_children);
199ATF_TEST_CASE_HEAD(interrupts_handler__kill_children)
200{
201    set_md_var("timeout", "10");
202}
203ATF_TEST_CASE_BODY(interrupts_handler__kill_children)
204{
205    std::auto_ptr< process::child > child1(process::child::fork_files(
206         pause_child, fs::path("/dev/stdout"), fs::path("/dev/stderr")));
207    std::auto_ptr< process::child > child2(process::child::fork_files(
208         pause_child, fs::path("/dev/stdout"), fs::path("/dev/stderr")));
209
210    signals::interrupts_handler interrupts;
211
212    // Our children pause until the reception of a signal.  Interrupting
213    // ourselves will cause the signal to be re-delivered to our children due to
214    // the interrupts_handler semantics.  If this does not happen, the wait
215    // calls below would block indefinitely and cause our test to time out.
216    ::kill(::getpid(), SIGHUP);
217
218    const process::status status1 = child1->wait();
219    ATF_REQUIRE(status1.signaled());
220    ATF_REQUIRE_EQ(SIGKILL, status1.termsig());
221    const process::status status2 = child2->wait();
222    ATF_REQUIRE(status2.signaled());
223    ATF_REQUIRE_EQ(SIGKILL, status2.termsig());
224}
225
226
227ATF_TEST_CASE_WITHOUT_HEAD(interrupts_inhibiter__sigalrm);
228ATF_TEST_CASE_BODY(interrupts_inhibiter__sigalrm)
229{
230    check_interrupts_inhibiter(SIGALRM);
231}
232
233
234ATF_TEST_CASE_WITHOUT_HEAD(interrupts_inhibiter__sighup);
235ATF_TEST_CASE_BODY(interrupts_inhibiter__sighup)
236{
237    check_interrupts_inhibiter(SIGHUP);
238}
239
240
241ATF_TEST_CASE_WITHOUT_HEAD(interrupts_inhibiter__sigint);
242ATF_TEST_CASE_BODY(interrupts_inhibiter__sigint)
243{
244    check_interrupts_inhibiter(SIGINT);
245}
246
247
248ATF_TEST_CASE_WITHOUT_HEAD(interrupts_inhibiter__sigterm);
249ATF_TEST_CASE_BODY(interrupts_inhibiter__sigterm)
250{
251    check_interrupts_inhibiter(SIGTERM);
252}
253
254
255ATF_INIT_TEST_CASES(tcs)
256{
257    ATF_ADD_TEST_CASE(tcs, interrupts_handler__sighup);
258    ATF_ADD_TEST_CASE(tcs, interrupts_handler__sigint);
259    ATF_ADD_TEST_CASE(tcs, interrupts_handler__sigterm);
260    ATF_ADD_TEST_CASE(tcs, interrupts_handler__kill_children);
261
262    ATF_ADD_TEST_CASE(tcs, interrupts_inhibiter__sigalrm);
263    ATF_ADD_TEST_CASE(tcs, interrupts_inhibiter__sighup);
264    ATF_ADD_TEST_CASE(tcs, interrupts_inhibiter__sigint);
265    ATF_ADD_TEST_CASE(tcs, interrupts_inhibiter__sigterm);
266}
267