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 "lldb/Host/HostInfo.h"
14 #include "lldb/Utility/ArchSpec.h"
15 #include <optional>
16 #include <sstream>
17
18 using namespace lldb_private;
19 using namespace llvm;
20
Signal(llvm::StringRef name,bool default_suppress,bool default_stop,bool default_notify,llvm::StringRef description,llvm::StringRef alias)21 UnixSignals::Signal::Signal(llvm::StringRef name, bool default_suppress,
22 bool default_stop, bool default_notify,
23 llvm::StringRef description, llvm::StringRef alias)
24 : m_name(name), m_alias(alias), m_description(description),
25 m_suppress(default_suppress), m_stop(default_stop),
26 m_notify(default_notify), m_default_suppress(default_suppress),
27 m_default_stop(default_stop), m_default_notify(default_notify) {}
28
Create(const ArchSpec & arch)29 lldb::UnixSignalsSP UnixSignals::Create(const ArchSpec &arch) {
30 const auto &triple = arch.GetTriple();
31 switch (triple.getOS()) {
32 case llvm::Triple::Linux:
33 return std::make_shared<LinuxSignals>();
34 case llvm::Triple::FreeBSD:
35 case llvm::Triple::OpenBSD:
36 return std::make_shared<FreeBSDSignals>();
37 case llvm::Triple::NetBSD:
38 return std::make_shared<NetBSDSignals>();
39 default:
40 return std::make_shared<UnixSignals>();
41 }
42 }
43
CreateForHost()44 lldb::UnixSignalsSP UnixSignals::CreateForHost() {
45 static lldb::UnixSignalsSP s_unix_signals_sp =
46 Create(HostInfo::GetArchitecture());
47 return s_unix_signals_sp;
48 }
49
50 // UnixSignals constructor
UnixSignals()51 UnixSignals::UnixSignals() { Reset(); }
52
UnixSignals(const UnixSignals & rhs)53 UnixSignals::UnixSignals(const UnixSignals &rhs) : m_signals(rhs.m_signals) {}
54
55 UnixSignals::~UnixSignals() = default;
56
Reset()57 void UnixSignals::Reset() {
58 // This builds one standard set of Unix Signals. If yours aren't quite in
59 // this order, you can either subclass this class, and use Add & Remove to
60 // change them or you can subclass and build them afresh in your constructor.
61 //
62 // Note: the signals below are the Darwin signals. Do not change these!
63
64 m_signals.clear();
65
66 // clang-format off
67 // SIGNO NAME SUPPRESS STOP NOTIFY DESCRIPTION
68 // ====== ============== ======== ====== ====== ===================================================
69 AddSignal(1, "SIGHUP", false, true, true, "hangup");
70 AddSignal(2, "SIGINT", true, true, true, "interrupt");
71 AddSignal(3, "SIGQUIT", false, true, true, "quit");
72 AddSignal(4, "SIGILL", false, true, true, "illegal instruction");
73 AddSignal(5, "SIGTRAP", true, true, true, "trace trap (not reset when caught)");
74 AddSignal(6, "SIGABRT", false, true, true, "abort()");
75 AddSignal(7, "SIGEMT", false, true, true, "pollable event");
76 AddSignal(8, "SIGFPE", false, true, true, "floating point exception");
77 AddSignal(9, "SIGKILL", false, true, true, "kill");
78 AddSignal(10, "SIGBUS", false, true, true, "bus error");
79 AddSignal(11, "SIGSEGV", false, true, true, "segmentation violation");
80 AddSignal(12, "SIGSYS", false, true, true, "bad argument to system call");
81 AddSignal(13, "SIGPIPE", false, false, false, "write on a pipe with no one to read it");
82 AddSignal(14, "SIGALRM", false, false, false, "alarm clock");
83 AddSignal(15, "SIGTERM", false, true, true, "software termination signal from kill");
84 AddSignal(16, "SIGURG", false, false, false, "urgent condition on IO channel");
85 AddSignal(17, "SIGSTOP", true, true, true, "sendable stop signal not from tty");
86 AddSignal(18, "SIGTSTP", false, true, true, "stop signal from tty");
87 AddSignal(19, "SIGCONT", false, false, true, "continue a stopped process");
88 AddSignal(20, "SIGCHLD", false, false, false, "to parent on child stop or exit");
89 AddSignal(21, "SIGTTIN", false, true, true, "to readers process group upon background tty read");
90 AddSignal(22, "SIGTTOU", false, true, true, "to readers process group upon background tty write");
91 AddSignal(23, "SIGIO", false, false, false, "input/output possible signal");
92 AddSignal(24, "SIGXCPU", false, true, true, "exceeded CPU time limit");
93 AddSignal(25, "SIGXFSZ", false, true, true, "exceeded file size limit");
94 AddSignal(26, "SIGVTALRM", false, false, false, "virtual time alarm");
95 AddSignal(27, "SIGPROF", false, false, false, "profiling time alarm");
96 AddSignal(28, "SIGWINCH", false, false, false, "window size changes");
97 AddSignal(29, "SIGINFO", false, true, true, "information request");
98 AddSignal(30, "SIGUSR1", false, true, true, "user defined signal 1");
99 AddSignal(31, "SIGUSR2", false, true, true, "user defined signal 2");
100 // clang-format on
101 }
102
AddSignal(int signo,llvm::StringRef name,bool default_suppress,bool default_stop,bool default_notify,llvm::StringRef description,llvm::StringRef alias)103 void UnixSignals::AddSignal(int signo, llvm::StringRef name,
104 bool default_suppress, bool default_stop,
105 bool default_notify, llvm::StringRef description,
106 llvm::StringRef alias) {
107 Signal new_signal(name, default_suppress, default_stop, default_notify,
108 description, alias);
109 m_signals.insert(std::make_pair(signo, new_signal));
110 ++m_version;
111 }
112
AddSignalCode(int signo,int code,const llvm::StringLiteral description,SignalCodePrintOption print_option)113 void UnixSignals::AddSignalCode(int signo, int code,
114 const llvm::StringLiteral description,
115 SignalCodePrintOption print_option) {
116 collection::iterator signal = m_signals.find(signo);
117 assert(signal != m_signals.end() &&
118 "Tried to add code to signal that does not exist.");
119 signal->second.m_codes.insert(
120 std::pair{code, SignalCode{description, print_option}});
121 ++m_version;
122 }
123
RemoveSignal(int signo)124 void UnixSignals::RemoveSignal(int signo) {
125 collection::iterator pos = m_signals.find(signo);
126 if (pos != m_signals.end())
127 m_signals.erase(pos);
128 ++m_version;
129 }
130
GetSignalAsStringRef(int32_t signo) const131 llvm::StringRef UnixSignals::GetSignalAsStringRef(int32_t signo) const {
132 const auto pos = m_signals.find(signo);
133 if (pos == m_signals.end())
134 return {};
135 return pos->second.m_name;
136 }
137
138 std::string
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) const139 UnixSignals::GetSignalDescription(int32_t signo, std::optional<int32_t> code,
140 std::optional<lldb::addr_t> addr,
141 std::optional<lldb::addr_t> lower,
142 std::optional<lldb::addr_t> upper) const {
143 std::string str;
144
145 collection::const_iterator pos = m_signals.find(signo);
146 if (pos != m_signals.end()) {
147 str = pos->second.m_name.str();
148
149 if (code) {
150 std::map<int32_t, SignalCode>::const_iterator cpos =
151 pos->second.m_codes.find(*code);
152 if (cpos != pos->second.m_codes.end()) {
153 const SignalCode &sc = cpos->second;
154 str += ": ";
155 if (sc.m_print_option != SignalCodePrintOption::Bounds)
156 str += sc.m_description.str();
157
158 std::stringstream strm;
159 switch (sc.m_print_option) {
160 case SignalCodePrintOption::None:
161 break;
162 case SignalCodePrintOption::Address:
163 if (addr)
164 strm << " (fault address: 0x" << std::hex << *addr << ")";
165 break;
166 case SignalCodePrintOption::Bounds:
167 if (lower && upper && addr) {
168 if ((unsigned long)(*addr) < *lower)
169 strm << "lower bound violation ";
170 else
171 strm << "upper bound violation ";
172
173 strm << "(fault address: 0x" << std::hex << *addr;
174 strm << ", lower bound: 0x" << std::hex << *lower;
175 strm << ", upper bound: 0x" << std::hex << *upper;
176 strm << ")";
177 } else
178 strm << sc.m_description.str();
179
180 break;
181 }
182 str += strm.str();
183 }
184 }
185 }
186
187 return str;
188 }
189
SignalIsValid(int32_t signo) const190 bool UnixSignals::SignalIsValid(int32_t signo) const {
191 return m_signals.find(signo) != m_signals.end();
192 }
193
GetShortName(llvm::StringRef name) const194 llvm::StringRef UnixSignals::GetShortName(llvm::StringRef name) const {
195 return name.substr(3); // Remove "SIG" from name
196 }
197
GetSignalNumberFromName(const char * name) const198 int32_t UnixSignals::GetSignalNumberFromName(const char *name) const {
199 llvm::StringRef name_ref(name);
200
201 collection::const_iterator pos, end = m_signals.end();
202 for (pos = m_signals.begin(); pos != end; pos++) {
203 if ((name_ref == pos->second.m_name) || (name_ref == pos->second.m_alias) ||
204 (name_ref == GetShortName(pos->second.m_name)) ||
205 (name_ref == GetShortName(pos->second.m_alias)))
206 return pos->first;
207 }
208
209 int32_t signo;
210 if (llvm::to_integer(name, signo))
211 return signo;
212 return LLDB_INVALID_SIGNAL_NUMBER;
213 }
214
GetFirstSignalNumber() const215 int32_t UnixSignals::GetFirstSignalNumber() const {
216 if (m_signals.empty())
217 return LLDB_INVALID_SIGNAL_NUMBER;
218
219 return (*m_signals.begin()).first;
220 }
221
GetNextSignalNumber(int32_t current_signal) const222 int32_t UnixSignals::GetNextSignalNumber(int32_t current_signal) const {
223 collection::const_iterator pos = m_signals.find(current_signal);
224 collection::const_iterator end = m_signals.end();
225 if (pos == end)
226 return LLDB_INVALID_SIGNAL_NUMBER;
227 else {
228 pos++;
229 if (pos == end)
230 return LLDB_INVALID_SIGNAL_NUMBER;
231 else
232 return pos->first;
233 }
234 }
235
GetSignalInfo(int32_t signo,bool & should_suppress,bool & should_stop,bool & should_notify) const236 bool UnixSignals::GetSignalInfo(int32_t signo, bool &should_suppress,
237 bool &should_stop, bool &should_notify) const {
238 const auto pos = m_signals.find(signo);
239 if (pos == m_signals.end())
240 return false;
241
242 const Signal &signal = pos->second;
243 should_suppress = signal.m_suppress;
244 should_stop = signal.m_stop;
245 should_notify = signal.m_notify;
246 return true;
247 }
248
GetShouldSuppress(int signo) const249 bool UnixSignals::GetShouldSuppress(int signo) const {
250 collection::const_iterator pos = m_signals.find(signo);
251 if (pos != m_signals.end())
252 return pos->second.m_suppress;
253 return false;
254 }
255
SetShouldSuppress(int signo,bool value)256 bool UnixSignals::SetShouldSuppress(int signo, bool value) {
257 collection::iterator pos = m_signals.find(signo);
258 if (pos != m_signals.end()) {
259 pos->second.m_suppress = value;
260 ++m_version;
261 return true;
262 }
263 return false;
264 }
265
SetShouldSuppress(const char * signal_name,bool value)266 bool UnixSignals::SetShouldSuppress(const char *signal_name, bool value) {
267 const int32_t signo = GetSignalNumberFromName(signal_name);
268 if (signo != LLDB_INVALID_SIGNAL_NUMBER)
269 return SetShouldSuppress(signo, value);
270 return false;
271 }
272
GetShouldStop(int signo) const273 bool UnixSignals::GetShouldStop(int signo) const {
274 collection::const_iterator pos = m_signals.find(signo);
275 if (pos != m_signals.end())
276 return pos->second.m_stop;
277 return false;
278 }
279
SetShouldStop(int signo,bool value)280 bool UnixSignals::SetShouldStop(int signo, bool value) {
281 collection::iterator pos = m_signals.find(signo);
282 if (pos != m_signals.end()) {
283 pos->second.m_stop = value;
284 ++m_version;
285 return true;
286 }
287 return false;
288 }
289
SetShouldStop(const char * signal_name,bool value)290 bool UnixSignals::SetShouldStop(const char *signal_name, bool value) {
291 const int32_t signo = GetSignalNumberFromName(signal_name);
292 if (signo != LLDB_INVALID_SIGNAL_NUMBER)
293 return SetShouldStop(signo, value);
294 return false;
295 }
296
GetShouldNotify(int signo) const297 bool UnixSignals::GetShouldNotify(int signo) const {
298 collection::const_iterator pos = m_signals.find(signo);
299 if (pos != m_signals.end())
300 return pos->second.m_notify;
301 return false;
302 }
303
SetShouldNotify(int signo,bool value)304 bool UnixSignals::SetShouldNotify(int signo, bool value) {
305 collection::iterator pos = m_signals.find(signo);
306 if (pos != m_signals.end()) {
307 pos->second.m_notify = value;
308 ++m_version;
309 return true;
310 }
311 return false;
312 }
313
SetShouldNotify(const char * signal_name,bool value)314 bool UnixSignals::SetShouldNotify(const char *signal_name, bool value) {
315 const int32_t signo = GetSignalNumberFromName(signal_name);
316 if (signo != LLDB_INVALID_SIGNAL_NUMBER)
317 return SetShouldNotify(signo, value);
318 return false;
319 }
320
GetNumSignals() const321 int32_t UnixSignals::GetNumSignals() const { return m_signals.size(); }
322
GetSignalAtIndex(int32_t index) const323 int32_t UnixSignals::GetSignalAtIndex(int32_t index) const {
324 if (index < 0 || m_signals.size() <= static_cast<size_t>(index))
325 return LLDB_INVALID_SIGNAL_NUMBER;
326 auto it = m_signals.begin();
327 std::advance(it, index);
328 return it->first;
329 }
330
GetVersion() const331 uint64_t UnixSignals::GetVersion() const { return m_version; }
332
333 std::vector<int32_t>
GetFilteredSignals(std::optional<bool> should_suppress,std::optional<bool> should_stop,std::optional<bool> should_notify)334 UnixSignals::GetFilteredSignals(std::optional<bool> should_suppress,
335 std::optional<bool> should_stop,
336 std::optional<bool> should_notify) {
337 std::vector<int32_t> result;
338 for (int32_t signo = GetFirstSignalNumber();
339 signo != LLDB_INVALID_SIGNAL_NUMBER;
340 signo = GetNextSignalNumber(signo)) {
341
342 bool signal_suppress = false;
343 bool signal_stop = false;
344 bool signal_notify = false;
345 GetSignalInfo(signo, signal_suppress, signal_stop, signal_notify);
346
347 // If any of filtering conditions are not met, we move on to the next
348 // signal.
349 if (should_suppress && signal_suppress != *should_suppress)
350 continue;
351
352 if (should_stop && signal_stop != *should_stop)
353 continue;
354
355 if (should_notify && signal_notify != *should_notify)
356 continue;
357
358 result.push_back(signo);
359 }
360
361 return result;
362 }
363
IncrementSignalHitCount(int signo)364 void UnixSignals::IncrementSignalHitCount(int signo) {
365 collection::iterator pos = m_signals.find(signo);
366 if (pos != m_signals.end())
367 pos->second.m_hit_count += 1;
368 }
369
GetHitCountStatistics() const370 json::Value UnixSignals::GetHitCountStatistics() const {
371 json::Array json_signals;
372 for (const auto &pair : m_signals) {
373 if (pair.second.m_hit_count > 0)
374 json_signals.emplace_back(
375 json::Object{{pair.second.m_name, pair.second.m_hit_count}});
376 }
377 return std::move(json_signals);
378 }
379
Reset(bool reset_stop,bool reset_notify,bool reset_suppress)380 void UnixSignals::Signal::Reset(bool reset_stop, bool reset_notify,
381 bool reset_suppress) {
382 if (reset_stop)
383 m_stop = m_default_stop;
384 if (reset_notify)
385 m_notify = m_default_notify;
386 if (reset_suppress)
387 m_suppress = m_default_suppress;
388 }
389
ResetSignal(int32_t signo,bool reset_stop,bool reset_notify,bool reset_suppress)390 bool UnixSignals::ResetSignal(int32_t signo, bool reset_stop,
391 bool reset_notify, bool reset_suppress) {
392 auto elem = m_signals.find(signo);
393 if (elem == m_signals.end())
394 return false;
395 (*elem).second.Reset(reset_stop, reset_notify, reset_suppress);
396 return true;
397 }
398
399