1 //===-- UnixSignals.cpp ---------------------------------------------------===//
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/NetBSDSignals.h"
13 #include "Plugins/Process/Utility/OpenBSDSignals.h"
14 #include "lldb/Host/HostInfo.h"
15 #include "lldb/Utility/ArchSpec.h"
16 #include <optional>
17 #include <sstream>
18
19 using namespace lldb_private;
20 using namespace llvm;
21
Signal(llvm::StringRef name,bool default_suppress,bool default_stop,bool default_notify,llvm::StringRef description,llvm::StringRef alias)22 UnixSignals::Signal::Signal(llvm::StringRef name, bool default_suppress,
23 bool default_stop, bool default_notify,
24 llvm::StringRef description, llvm::StringRef alias)
25 : m_name(name), m_alias(alias), m_description(description),
26 m_suppress(default_suppress), m_stop(default_stop),
27 m_notify(default_notify), m_default_suppress(default_suppress),
28 m_default_stop(default_stop), m_default_notify(default_notify) {}
29
Create(const ArchSpec & arch)30 lldb::UnixSignalsSP UnixSignals::Create(const ArchSpec &arch) {
31 const auto &triple = arch.GetTriple();
32 switch (triple.getOS()) {
33 case llvm::Triple::Linux:
34 return std::make_shared<LinuxSignals>();
35 case llvm::Triple::FreeBSD:
36 return std::make_shared<FreeBSDSignals>();
37 case llvm::Triple::NetBSD:
38 return std::make_shared<NetBSDSignals>();
39 case llvm::Triple::OpenBSD:
40 return std::make_shared<OpenBSDSignals>();
41 default:
42 return std::make_shared<UnixSignals>();
43 }
44 }
45
CreateForHost()46 lldb::UnixSignalsSP UnixSignals::CreateForHost() {
47 static lldb::UnixSignalsSP s_unix_signals_sp =
48 Create(HostInfo::GetArchitecture());
49 return s_unix_signals_sp;
50 }
51
52 // UnixSignals constructor
UnixSignals()53 UnixSignals::UnixSignals() { Reset(); }
54
UnixSignals(const UnixSignals & rhs)55 UnixSignals::UnixSignals(const UnixSignals &rhs) : m_signals(rhs.m_signals) {}
56
57 UnixSignals::~UnixSignals() = default;
58
Reset()59 void UnixSignals::Reset() {
60 // This builds one standard set of Unix Signals. If yours aren't quite in
61 // this order, you can either subclass this class, and use Add & Remove to
62 // change them or you can subclass and build them afresh in your constructor.
63 //
64 // Note: the signals below are the Darwin signals. Do not change these!
65
66 m_signals.clear();
67
68 // clang-format off
69 // SIGNO NAME SUPPRESS STOP NOTIFY DESCRIPTION
70 // ====== ============== ======== ====== ====== ===================================================
71 AddSignal(1, "SIGHUP", false, true, true, "hangup");
72 AddSignal(2, "SIGINT", true, true, true, "interrupt");
73 AddSignal(3, "SIGQUIT", false, true, true, "quit");
74 AddSignal(4, "SIGILL", false, true, true, "illegal instruction");
75 AddSignal(5, "SIGTRAP", true, true, true, "trace trap (not reset when caught)");
76 AddSignal(6, "SIGABRT", false, true, true, "abort()");
77 AddSignal(7, "SIGEMT", false, true, true, "pollable event");
78 AddSignal(8, "SIGFPE", false, true, true, "floating point exception");
79 AddSignal(9, "SIGKILL", false, true, true, "kill");
80 AddSignal(10, "SIGBUS", false, true, true, "bus error");
81 AddSignal(11, "SIGSEGV", false, true, true, "segmentation violation");
82 AddSignal(12, "SIGSYS", false, true, true, "bad argument to system call");
83 AddSignal(13, "SIGPIPE", false, false, false, "write on a pipe with no one to read it");
84 AddSignal(14, "SIGALRM", false, false, false, "alarm clock");
85 AddSignal(15, "SIGTERM", false, true, true, "software termination signal from kill");
86 AddSignal(16, "SIGURG", false, false, false, "urgent condition on IO channel");
87 AddSignal(17, "SIGSTOP", true, true, true, "sendable stop signal not from tty");
88 AddSignal(18, "SIGTSTP", false, true, true, "stop signal from tty");
89 AddSignal(19, "SIGCONT", false, false, true, "continue a stopped process");
90 AddSignal(20, "SIGCHLD", false, false, false, "to parent on child stop or exit");
91 AddSignal(21, "SIGTTIN", false, true, true, "to readers process group upon background tty read");
92 AddSignal(22, "SIGTTOU", false, true, true, "to readers process group upon background tty write");
93 AddSignal(23, "SIGIO", false, false, false, "input/output possible signal");
94 AddSignal(24, "SIGXCPU", false, true, true, "exceeded CPU time limit");
95 AddSignal(25, "SIGXFSZ", false, true, true, "exceeded file size limit");
96 AddSignal(26, "SIGVTALRM", false, false, false, "virtual time alarm");
97 AddSignal(27, "SIGPROF", false, false, false, "profiling time alarm");
98 AddSignal(28, "SIGWINCH", false, false, false, "window size changes");
99 AddSignal(29, "SIGINFO", false, true, true, "information request");
100 AddSignal(30, "SIGUSR1", false, true, true, "user defined signal 1");
101 AddSignal(31, "SIGUSR2", false, true, true, "user defined signal 2");
102 // clang-format on
103 }
104
AddSignal(int signo,llvm::StringRef name,bool default_suppress,bool default_stop,bool default_notify,llvm::StringRef description,llvm::StringRef alias)105 void UnixSignals::AddSignal(int signo, llvm::StringRef name,
106 bool default_suppress, bool default_stop,
107 bool default_notify, llvm::StringRef description,
108 llvm::StringRef alias) {
109 Signal new_signal(name, default_suppress, default_stop, default_notify,
110 description, alias);
111 m_signals.insert(std::make_pair(signo, new_signal));
112 ++m_version;
113 }
114
AddSignalCode(int signo,int code,const llvm::StringLiteral description,SignalCodePrintOption print_option)115 void UnixSignals::AddSignalCode(int signo, int code,
116 const llvm::StringLiteral description,
117 SignalCodePrintOption print_option) {
118 collection::iterator signal = m_signals.find(signo);
119 assert(signal != m_signals.end() &&
120 "Tried to add code to signal that does not exist.");
121 signal->second.m_codes.insert(
122 std::pair{code, SignalCode{description, print_option}});
123 ++m_version;
124 }
125
RemoveSignal(int signo)126 void UnixSignals::RemoveSignal(int signo) {
127 collection::iterator pos = m_signals.find(signo);
128 if (pos != m_signals.end())
129 m_signals.erase(pos);
130 ++m_version;
131 }
132
GetSignalAsStringRef(int32_t signo) const133 llvm::StringRef UnixSignals::GetSignalAsStringRef(int32_t signo) const {
134 const auto pos = m_signals.find(signo);
135 if (pos == m_signals.end())
136 return {};
137 return pos->second.m_name;
138 }
139
GetSignalDescription(int32_t signo,std::optional<int32_t> code,std::optional<lldb::addr_t> addr,std::optional<lldb::addr_t> lower,std::optional<lldb::addr_t> upper,std::optional<uint32_t> pid,std::optional<uint32_t> uid) const140 std::string UnixSignals::GetSignalDescription(
141 int32_t signo, std::optional<int32_t> code,
142 std::optional<lldb::addr_t> addr, std::optional<lldb::addr_t> lower,
143 std::optional<lldb::addr_t> upper, std::optional<uint32_t> pid,
144 std::optional<uint32_t> uid) const {
145 std::string str;
146
147 collection::const_iterator pos = m_signals.find(signo);
148 if (pos != m_signals.end()) {
149 str = pos->second.m_name.str();
150
151 if (code) {
152 std::map<int32_t, SignalCode>::const_iterator cpos =
153 pos->second.m_codes.find(*code);
154 if (cpos != pos->second.m_codes.end()) {
155 const SignalCode &sc = cpos->second;
156 str += ": ";
157 if (sc.m_print_option != SignalCodePrintOption::Bounds)
158 str += sc.m_description.str();
159
160 std::stringstream strm;
161 switch (sc.m_print_option) {
162 case SignalCodePrintOption::None:
163 break;
164 case SignalCodePrintOption::Address:
165 if (addr)
166 strm << " (fault address=0x" << std::hex << *addr << ")";
167 break;
168 case SignalCodePrintOption::Bounds:
169 if (lower && upper && addr) {
170 if ((unsigned long)(*addr) < *lower)
171 strm << "lower bound violation ";
172 else
173 strm << "upper bound violation ";
174
175 strm << "(fault address=0x" << std::hex << *addr;
176 strm << ", lower bound=0x" << std::hex << *lower;
177 strm << ", upper bound=0x" << std::hex << *upper;
178 strm << ")";
179 } else
180 strm << sc.m_description.str();
181
182 break;
183 case SignalCodePrintOption::Sender:
184 if (pid && uid)
185 strm << " (sender pid=" << *pid << ", uid=" << *uid << ")";
186 break;
187 }
188 str += strm.str();
189 }
190 }
191 }
192
193 return str;
194 }
195
SignalIsValid(int32_t signo) const196 bool UnixSignals::SignalIsValid(int32_t signo) const {
197 return m_signals.find(signo) != m_signals.end();
198 }
199
GetShortName(llvm::StringRef name) const200 llvm::StringRef UnixSignals::GetShortName(llvm::StringRef name) const {
201 return name.substr(3); // Remove "SIG" from name
202 }
203
GetSignalNumberFromName(const char * name) const204 int32_t UnixSignals::GetSignalNumberFromName(const char *name) const {
205 llvm::StringRef name_ref(name);
206
207 collection::const_iterator pos, end = m_signals.end();
208 for (pos = m_signals.begin(); pos != end; pos++) {
209 if ((name_ref == pos->second.m_name) || (name_ref == pos->second.m_alias) ||
210 (name_ref == GetShortName(pos->second.m_name)) ||
211 (name_ref == GetShortName(pos->second.m_alias)))
212 return pos->first;
213 }
214
215 int32_t signo;
216 if (llvm::to_integer(name, signo))
217 return signo;
218 return LLDB_INVALID_SIGNAL_NUMBER;
219 }
220
GetFirstSignalNumber() const221 int32_t UnixSignals::GetFirstSignalNumber() const {
222 if (m_signals.empty())
223 return LLDB_INVALID_SIGNAL_NUMBER;
224
225 return (*m_signals.begin()).first;
226 }
227
GetNextSignalNumber(int32_t current_signal) const228 int32_t UnixSignals::GetNextSignalNumber(int32_t current_signal) const {
229 collection::const_iterator pos = m_signals.find(current_signal);
230 collection::const_iterator end = m_signals.end();
231 if (pos == end)
232 return LLDB_INVALID_SIGNAL_NUMBER;
233 else {
234 pos++;
235 if (pos == end)
236 return LLDB_INVALID_SIGNAL_NUMBER;
237 else
238 return pos->first;
239 }
240 }
241
GetSignalInfo(int32_t signo,bool & should_suppress,bool & should_stop,bool & should_notify) const242 bool UnixSignals::GetSignalInfo(int32_t signo, bool &should_suppress,
243 bool &should_stop, bool &should_notify) const {
244 const auto pos = m_signals.find(signo);
245 if (pos == m_signals.end())
246 return false;
247
248 const Signal &signal = pos->second;
249 should_suppress = signal.m_suppress;
250 should_stop = signal.m_stop;
251 should_notify = signal.m_notify;
252 return true;
253 }
254
GetShouldSuppress(int signo) const255 bool UnixSignals::GetShouldSuppress(int signo) const {
256 collection::const_iterator pos = m_signals.find(signo);
257 if (pos != m_signals.end())
258 return pos->second.m_suppress;
259 return false;
260 }
261
SetShouldSuppress(int signo,bool value)262 bool UnixSignals::SetShouldSuppress(int signo, bool value) {
263 collection::iterator pos = m_signals.find(signo);
264 if (pos != m_signals.end()) {
265 pos->second.m_suppress = value;
266 ++m_version;
267 return true;
268 }
269 return false;
270 }
271
SetShouldSuppress(const char * signal_name,bool value)272 bool UnixSignals::SetShouldSuppress(const char *signal_name, bool value) {
273 const int32_t signo = GetSignalNumberFromName(signal_name);
274 if (signo != LLDB_INVALID_SIGNAL_NUMBER)
275 return SetShouldSuppress(signo, value);
276 return false;
277 }
278
GetShouldStop(int signo) const279 bool UnixSignals::GetShouldStop(int signo) const {
280 collection::const_iterator pos = m_signals.find(signo);
281 if (pos != m_signals.end())
282 return pos->second.m_stop;
283 return false;
284 }
285
SetShouldStop(int signo,bool value)286 bool UnixSignals::SetShouldStop(int signo, bool value) {
287 collection::iterator pos = m_signals.find(signo);
288 if (pos != m_signals.end()) {
289 pos->second.m_stop = value;
290 ++m_version;
291 return true;
292 }
293 return false;
294 }
295
SetShouldStop(const char * signal_name,bool value)296 bool UnixSignals::SetShouldStop(const char *signal_name, bool value) {
297 const int32_t signo = GetSignalNumberFromName(signal_name);
298 if (signo != LLDB_INVALID_SIGNAL_NUMBER)
299 return SetShouldStop(signo, value);
300 return false;
301 }
302
GetShouldNotify(int signo) const303 bool UnixSignals::GetShouldNotify(int signo) const {
304 collection::const_iterator pos = m_signals.find(signo);
305 if (pos != m_signals.end())
306 return pos->second.m_notify;
307 return false;
308 }
309
SetShouldNotify(int signo,bool value)310 bool UnixSignals::SetShouldNotify(int signo, bool value) {
311 collection::iterator pos = m_signals.find(signo);
312 if (pos != m_signals.end()) {
313 pos->second.m_notify = value;
314 ++m_version;
315 return true;
316 }
317 return false;
318 }
319
SetShouldNotify(const char * signal_name,bool value)320 bool UnixSignals::SetShouldNotify(const char *signal_name, bool value) {
321 const int32_t signo = GetSignalNumberFromName(signal_name);
322 if (signo != LLDB_INVALID_SIGNAL_NUMBER)
323 return SetShouldNotify(signo, value);
324 return false;
325 }
326
GetNumSignals() const327 int32_t UnixSignals::GetNumSignals() const { return m_signals.size(); }
328
GetSignalAtIndex(int32_t index) const329 int32_t UnixSignals::GetSignalAtIndex(int32_t index) const {
330 if (index < 0 || m_signals.size() <= static_cast<size_t>(index))
331 return LLDB_INVALID_SIGNAL_NUMBER;
332 auto it = m_signals.begin();
333 std::advance(it, index);
334 return it->first;
335 }
336
GetVersion() const337 uint64_t UnixSignals::GetVersion() const { return m_version; }
338
339 std::vector<int32_t>
GetFilteredSignals(std::optional<bool> should_suppress,std::optional<bool> should_stop,std::optional<bool> should_notify)340 UnixSignals::GetFilteredSignals(std::optional<bool> should_suppress,
341 std::optional<bool> should_stop,
342 std::optional<bool> should_notify) {
343 std::vector<int32_t> result;
344 for (int32_t signo = GetFirstSignalNumber();
345 signo != LLDB_INVALID_SIGNAL_NUMBER;
346 signo = GetNextSignalNumber(signo)) {
347
348 bool signal_suppress = false;
349 bool signal_stop = false;
350 bool signal_notify = false;
351 GetSignalInfo(signo, signal_suppress, signal_stop, signal_notify);
352
353 // If any of filtering conditions are not met, we move on to the next
354 // signal.
355 if (should_suppress && signal_suppress != *should_suppress)
356 continue;
357
358 if (should_stop && signal_stop != *should_stop)
359 continue;
360
361 if (should_notify && signal_notify != *should_notify)
362 continue;
363
364 result.push_back(signo);
365 }
366
367 return result;
368 }
369
IncrementSignalHitCount(int signo)370 void UnixSignals::IncrementSignalHitCount(int signo) {
371 collection::iterator pos = m_signals.find(signo);
372 if (pos != m_signals.end())
373 pos->second.m_hit_count += 1;
374 }
375
GetHitCountStatistics() const376 json::Value UnixSignals::GetHitCountStatistics() const {
377 json::Array json_signals;
378 for (const auto &pair : m_signals) {
379 if (pair.second.m_hit_count > 0)
380 json_signals.emplace_back(
381 json::Object{{pair.second.m_name, pair.second.m_hit_count}});
382 }
383 return std::move(json_signals);
384 }
385
Reset(bool reset_stop,bool reset_notify,bool reset_suppress)386 void UnixSignals::Signal::Reset(bool reset_stop, bool reset_notify,
387 bool reset_suppress) {
388 if (reset_stop)
389 m_stop = m_default_stop;
390 if (reset_notify)
391 m_notify = m_default_notify;
392 if (reset_suppress)
393 m_suppress = m_default_suppress;
394 }
395
ResetSignal(int32_t signo,bool reset_stop,bool reset_notify,bool reset_suppress)396 bool UnixSignals::ResetSignal(int32_t signo, bool reset_stop,
397 bool reset_notify, bool reset_suppress) {
398 auto elem = m_signals.find(signo);
399 if (elem == m_signals.end())
400 return false;
401 (*elem).second.Reset(reset_stop, reset_notify, reset_suppress);
402 return true;
403 }
404