1//===-- UnixSignals.cpp -----------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "lldb/Target/UnixSignals.h"
10#include "Plugins/Process/Utility/FreeBSDSignals.h"
11#include "Plugins/Process/Utility/LinuxSignals.h"
12#include "Plugins/Process/Utility/MipsLinuxSignals.h"
13#include "Plugins/Process/Utility/NetBSDSignals.h"
14#include "lldb/Host/HostInfo.h"
15#include "lldb/Host/StringConvert.h"
16#include "lldb/Utility/ArchSpec.h"
17
18using namespace lldb_private;
19
20UnixSignals::Signal::Signal(const char *name, bool default_suppress,
21                            bool default_stop, bool default_notify,
22                            const char *description, const char *alias)
23    : m_name(name), m_alias(alias), m_description(),
24      m_suppress(default_suppress), m_stop(default_stop),
25      m_notify(default_notify) {
26  if (description)
27    m_description.assign(description);
28}
29
30lldb::UnixSignalsSP UnixSignals::Create(const ArchSpec &arch) {
31  const auto &triple = arch.GetTriple();
32  switch (triple.getOS()) {
33  case llvm::Triple::Linux: {
34    switch (triple.getArch()) {
35    case llvm::Triple::mips:
36    case llvm::Triple::mipsel:
37    case llvm::Triple::mips64:
38    case llvm::Triple::mips64el:
39      return std::make_shared<MipsLinuxSignals>();
40    default:
41      return std::make_shared<LinuxSignals>();
42    }
43  }
44  case llvm::Triple::FreeBSD:
45  case llvm::Triple::OpenBSD:
46    return std::make_shared<FreeBSDSignals>();
47  case llvm::Triple::NetBSD:
48    return std::make_shared<NetBSDSignals>();
49  default:
50    return std::make_shared<UnixSignals>();
51  }
52}
53
54lldb::UnixSignalsSP UnixSignals::CreateForHost() {
55  static lldb::UnixSignalsSP s_unix_signals_sp =
56      Create(HostInfo::GetArchitecture());
57  return s_unix_signals_sp;
58}
59
60// UnixSignals constructor
61UnixSignals::UnixSignals() { Reset(); }
62
63UnixSignals::UnixSignals(const UnixSignals &rhs) : m_signals(rhs.m_signals) {}
64
65UnixSignals::~UnixSignals() = default;
66
67void UnixSignals::Reset() {
68  // This builds one standard set of Unix Signals.  If yours aren't quite in
69  // this order, you can either subclass this class, and use Add & Remove to
70  // change them
71  // or you can subclass and build them afresh in your constructor;
72  //
73  // Note: the signals below are the Darwin signals.  Do not change these!
74  m_signals.clear();
75  //        SIGNO  NAME          SUPPRESS STOP   NOTIFY DESCRIPTION
76  //        ====== ============  ======== ====== ======
77  //        ===================================================
78  AddSignal(1, "SIGHUP", false, true, true, "hangup");
79  AddSignal(2, "SIGINT", true, true, true, "interrupt");
80  AddSignal(3, "SIGQUIT", false, true, true, "quit");
81  AddSignal(4, "SIGILL", false, true, true, "illegal instruction");
82  AddSignal(5, "SIGTRAP", true, true, true,
83            "trace trap (not reset when caught)");
84  AddSignal(6, "SIGABRT", false, true, true, "abort()");
85  AddSignal(7, "SIGEMT", false, true, true, "pollable event");
86  AddSignal(8, "SIGFPE", false, true, true, "floating point exception");
87  AddSignal(9, "SIGKILL", false, true, true, "kill");
88  AddSignal(10, "SIGBUS", false, true, true, "bus error");
89  AddSignal(11, "SIGSEGV", false, true, true, "segmentation violation");
90  AddSignal(12, "SIGSYS", false, true, true, "bad argument to system call");
91  AddSignal(13, "SIGPIPE", false, false, false,
92            "write on a pipe with no one to read it");
93  AddSignal(14, "SIGALRM", false, false, false, "alarm clock");
94  AddSignal(15, "SIGTERM", false, true, true,
95            "software termination signal from kill");
96  AddSignal(16, "SIGURG", false, false, false,
97            "urgent condition on IO channel");
98  AddSignal(17, "SIGSTOP", true, true, true,
99            "sendable stop signal not from tty");
100  AddSignal(18, "SIGTSTP", false, true, true, "stop signal from tty");
101  AddSignal(19, "SIGCONT", false, true, true, "continue a stopped process");
102  AddSignal(20, "SIGCHLD", false, false, false,
103            "to parent on child stop or exit");
104  AddSignal(21, "SIGTTIN", false, true, true,
105            "to readers process group upon background tty read");
106  AddSignal(22, "SIGTTOU", false, true, true,
107            "to readers process group upon background tty write");
108  AddSignal(23, "SIGIO", false, false, false, "input/output possible signal");
109  AddSignal(24, "SIGXCPU", false, true, true, "exceeded CPU time limit");
110  AddSignal(25, "SIGXFSZ", false, true, true, "exceeded file size limit");
111  AddSignal(26, "SIGVTALRM", false, false, false, "virtual time alarm");
112  AddSignal(27, "SIGPROF", false, false, false, "profiling time alarm");
113  AddSignal(28, "SIGWINCH", false, false, false, "window size changes");
114  AddSignal(29, "SIGINFO", false, true, true, "information request");
115  AddSignal(30, "SIGUSR1", false, true, true, "user defined signal 1");
116  AddSignal(31, "SIGUSR2", false, true, true, "user defined signal 2");
117}
118
119void UnixSignals::AddSignal(int signo, const char *name, bool default_suppress,
120                            bool default_stop, bool default_notify,
121                            const char *description, const char *alias) {
122  Signal new_signal(name, default_suppress, default_stop, default_notify,
123                    description, alias);
124  m_signals.insert(std::make_pair(signo, new_signal));
125  ++m_version;
126}
127
128void UnixSignals::RemoveSignal(int signo) {
129  collection::iterator pos = m_signals.find(signo);
130  if (pos != m_signals.end())
131    m_signals.erase(pos);
132  ++m_version;
133}
134
135const char *UnixSignals::GetSignalAsCString(int signo) const {
136  collection::const_iterator pos = m_signals.find(signo);
137  if (pos == m_signals.end())
138    return nullptr;
139  else
140    return pos->second.m_name.GetCString();
141}
142
143bool UnixSignals::SignalIsValid(int32_t signo) const {
144  return m_signals.find(signo) != m_signals.end();
145}
146
147ConstString UnixSignals::GetShortName(ConstString name) const {
148  if (name) {
149    const char *signame = name.AsCString();
150    return ConstString(signame + 3); // Remove "SIG" from name
151  }
152  return name;
153}
154
155int32_t UnixSignals::GetSignalNumberFromName(const char *name) const {
156  ConstString const_name(name);
157
158  collection::const_iterator pos, end = m_signals.end();
159  for (pos = m_signals.begin(); pos != end; pos++) {
160    if ((const_name == pos->second.m_name) ||
161        (const_name == pos->second.m_alias) ||
162        (const_name == GetShortName(pos->second.m_name)) ||
163        (const_name == GetShortName(pos->second.m_alias)))
164      return pos->first;
165  }
166
167  const int32_t signo =
168      StringConvert::ToSInt32(name, LLDB_INVALID_SIGNAL_NUMBER, 0);
169  if (signo != LLDB_INVALID_SIGNAL_NUMBER)
170    return signo;
171  return LLDB_INVALID_SIGNAL_NUMBER;
172}
173
174int32_t UnixSignals::GetFirstSignalNumber() const {
175  if (m_signals.empty())
176    return LLDB_INVALID_SIGNAL_NUMBER;
177
178  return (*m_signals.begin()).first;
179}
180
181int32_t UnixSignals::GetNextSignalNumber(int32_t current_signal) const {
182  collection::const_iterator pos = m_signals.find(current_signal);
183  collection::const_iterator end = m_signals.end();
184  if (pos == end)
185    return LLDB_INVALID_SIGNAL_NUMBER;
186  else {
187    pos++;
188    if (pos == end)
189      return LLDB_INVALID_SIGNAL_NUMBER;
190    else
191      return pos->first;
192  }
193}
194
195const char *UnixSignals::GetSignalInfo(int32_t signo, bool &should_suppress,
196                                       bool &should_stop,
197                                       bool &should_notify) const {
198  collection::const_iterator pos = m_signals.find(signo);
199  if (pos == m_signals.end())
200    return nullptr;
201  else {
202    const Signal &signal = pos->second;
203    should_suppress = signal.m_suppress;
204    should_stop = signal.m_stop;
205    should_notify = signal.m_notify;
206    return signal.m_name.AsCString("");
207  }
208}
209
210bool UnixSignals::GetShouldSuppress(int signo) const {
211  collection::const_iterator pos = m_signals.find(signo);
212  if (pos != m_signals.end())
213    return pos->second.m_suppress;
214  return false;
215}
216
217bool UnixSignals::SetShouldSuppress(int signo, bool value) {
218  collection::iterator pos = m_signals.find(signo);
219  if (pos != m_signals.end()) {
220    pos->second.m_suppress = value;
221    ++m_version;
222    return true;
223  }
224  return false;
225}
226
227bool UnixSignals::SetShouldSuppress(const char *signal_name, bool value) {
228  const int32_t signo = GetSignalNumberFromName(signal_name);
229  if (signo != LLDB_INVALID_SIGNAL_NUMBER)
230    return SetShouldSuppress(signo, value);
231  return false;
232}
233
234bool UnixSignals::GetShouldStop(int signo) const {
235  collection::const_iterator pos = m_signals.find(signo);
236  if (pos != m_signals.end())
237    return pos->second.m_stop;
238  return false;
239}
240
241bool UnixSignals::SetShouldStop(int signo, bool value) {
242  collection::iterator pos = m_signals.find(signo);
243  if (pos != m_signals.end()) {
244    pos->second.m_stop = value;
245    ++m_version;
246    return true;
247  }
248  return false;
249}
250
251bool UnixSignals::SetShouldStop(const char *signal_name, bool value) {
252  const int32_t signo = GetSignalNumberFromName(signal_name);
253  if (signo != LLDB_INVALID_SIGNAL_NUMBER)
254    return SetShouldStop(signo, value);
255  return false;
256}
257
258bool UnixSignals::GetShouldNotify(int signo) const {
259  collection::const_iterator pos = m_signals.find(signo);
260  if (pos != m_signals.end())
261    return pos->second.m_notify;
262  return false;
263}
264
265bool UnixSignals::SetShouldNotify(int signo, bool value) {
266  collection::iterator pos = m_signals.find(signo);
267  if (pos != m_signals.end()) {
268    pos->second.m_notify = value;
269    ++m_version;
270    return true;
271  }
272  return false;
273}
274
275bool UnixSignals::SetShouldNotify(const char *signal_name, bool value) {
276  const int32_t signo = GetSignalNumberFromName(signal_name);
277  if (signo != LLDB_INVALID_SIGNAL_NUMBER)
278    return SetShouldNotify(signo, value);
279  return false;
280}
281
282int32_t UnixSignals::GetNumSignals() const { return m_signals.size(); }
283
284int32_t UnixSignals::GetSignalAtIndex(int32_t index) const {
285  if (index < 0 || m_signals.size() <= static_cast<size_t>(index))
286    return LLDB_INVALID_SIGNAL_NUMBER;
287  auto it = m_signals.begin();
288  std::advance(it, index);
289  return it->first;
290}
291
292uint64_t UnixSignals::GetVersion() const { return m_version; }
293
294std::vector<int32_t>
295UnixSignals::GetFilteredSignals(llvm::Optional<bool> should_suppress,
296                                llvm::Optional<bool> should_stop,
297                                llvm::Optional<bool> should_notify) {
298  std::vector<int32_t> result;
299  for (int32_t signo = GetFirstSignalNumber();
300       signo != LLDB_INVALID_SIGNAL_NUMBER;
301       signo = GetNextSignalNumber(signo)) {
302
303    bool signal_suppress = false;
304    bool signal_stop = false;
305    bool signal_notify = false;
306    GetSignalInfo(signo, signal_suppress, signal_stop, signal_notify);
307
308    // If any of filtering conditions are not met, we move on to the next
309    // signal.
310    if (should_suppress.hasValue() &&
311        signal_suppress != should_suppress.getValue())
312      continue;
313
314    if (should_stop.hasValue() && signal_stop != should_stop.getValue())
315      continue;
316
317    if (should_notify.hasValue() && signal_notify != should_notify.getValue())
318      continue;
319
320    result.push_back(signo);
321  }
322
323  return result;
324}
325