1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "logging.h"
18 
19 #include <iostream>
20 #include <limits>
21 #include <sstream>
22 
23 #include "base/mutex.h"
24 #include "runtime.h"
25 #include "thread-inl.h"
26 #include "utils.h"
27 
28 // Headers for LogMessage::LogLine.
29 #ifdef __ANDROID__
30 #include "cutils/log.h"
31 #else
32 #include <sys/types.h>
33 #include <unistd.h>
34 #endif
35 
36 namespace art {
37 
38 LogVerbosity gLogVerbosity;
39 
40 unsigned int gAborting = 0;
41 
42 static LogSeverity gMinimumLogSeverity = INFO;
43 static std::unique_ptr<std::string> gCmdLine;
44 static std::unique_ptr<std::string> gProgramInvocationName;
45 static std::unique_ptr<std::string> gProgramInvocationShortName;
46 
47 // Print INTERNAL_FATAL messages directly instead of at destruction time. This only works on the
48 // host right now: for the device, a stream buf collating output into lines and calling LogLine or
49 // lower-level logging is necessary.
50 #ifdef __ANDROID__
51 static constexpr bool kPrintInternalFatalDirectly = false;
52 #else
53 static constexpr bool kPrintInternalFatalDirectly = !kIsTargetBuild;
54 #endif
55 
PrintDirectly(LogSeverity severity)56 static bool PrintDirectly(LogSeverity severity) {
57   return kPrintInternalFatalDirectly && severity == INTERNAL_FATAL;
58 }
59 
GetCmdLine()60 const char* GetCmdLine() {
61   return (gCmdLine.get() != nullptr) ? gCmdLine->c_str() : nullptr;
62 }
63 
ProgramInvocationName()64 const char* ProgramInvocationName() {
65   return (gProgramInvocationName.get() != nullptr) ? gProgramInvocationName->c_str() : "art";
66 }
67 
ProgramInvocationShortName()68 const char* ProgramInvocationShortName() {
69   return (gProgramInvocationShortName.get() != nullptr) ? gProgramInvocationShortName->c_str()
70                                                         : "art";
71 }
72 
InitLogging(char * argv[])73 void InitLogging(char* argv[]) {
74   if (gCmdLine.get() != nullptr) {
75     return;
76   }
77   // TODO: Move this to a more obvious InitART...
78   Locks::Init();
79 
80   // Stash the command line for later use. We can use /proc/self/cmdline on Linux to recover this,
81   // but we don't have that luxury on the Mac, and there are a couple of argv[0] variants that are
82   // commonly used.
83   if (argv != nullptr) {
84     gCmdLine.reset(new std::string(argv[0]));
85     for (size_t i = 1; argv[i] != nullptr; ++i) {
86       gCmdLine->append(" ");
87       gCmdLine->append(argv[i]);
88     }
89     gProgramInvocationName.reset(new std::string(argv[0]));
90     const char* last_slash = strrchr(argv[0], '/');
91     gProgramInvocationShortName.reset(new std::string((last_slash != nullptr) ? last_slash + 1
92                                                                            : argv[0]));
93   } else {
94     // TODO: fall back to /proc/self/cmdline when argv is null on Linux.
95     gCmdLine.reset(new std::string("<unset>"));
96   }
97   const char* tags = getenv("ANDROID_LOG_TAGS");
98   if (tags == nullptr) {
99     return;
100   }
101 
102   std::vector<std::string> specs;
103   Split(tags, ' ', &specs);
104   for (size_t i = 0; i < specs.size(); ++i) {
105     // "tag-pattern:[vdiwefs]"
106     std::string spec(specs[i]);
107     if (spec.size() == 3 && StartsWith(spec, "*:")) {
108       switch (spec[2]) {
109         case 'v':
110           gMinimumLogSeverity = VERBOSE;
111           continue;
112         case 'd':
113           gMinimumLogSeverity = DEBUG;
114           continue;
115         case 'i':
116           gMinimumLogSeverity = INFO;
117           continue;
118         case 'w':
119           gMinimumLogSeverity = WARNING;
120           continue;
121         case 'e':
122           gMinimumLogSeverity = ERROR;
123           continue;
124         case 'f':
125           gMinimumLogSeverity = FATAL;
126           continue;
127         // liblog will even suppress FATAL if you say 's' for silent, but that's crazy!
128         case 's':
129           gMinimumLogSeverity = FATAL;
130           continue;
131       }
132     }
133     LOG(FATAL) << "unsupported '" << spec << "' in ANDROID_LOG_TAGS (" << tags << ")";
134   }
135 }
136 
137 // This indirection greatly reduces the stack impact of having
138 // lots of checks/logging in a function.
139 class LogMessageData {
140  public:
LogMessageData(const char * file,unsigned int line,LogSeverity severity,int error)141   LogMessageData(const char* file, unsigned int line, LogSeverity severity, int error)
142       : file_(file),
143         line_number_(line),
144         severity_(severity),
145         error_(error) {
146     const char* last_slash = strrchr(file, '/');
147     file = (last_slash == nullptr) ? file : last_slash + 1;
148   }
149 
GetFile() const150   const char * GetFile() const {
151     return file_;
152   }
153 
GetLineNumber() const154   unsigned int GetLineNumber() const {
155     return line_number_;
156   }
157 
GetSeverity() const158   LogSeverity GetSeverity() const {
159     return severity_;
160   }
161 
GetError() const162   int GetError() const {
163     return error_;
164   }
165 
GetBuffer()166   std::ostream& GetBuffer() {
167     return buffer_;
168   }
169 
ToString() const170   std::string ToString() const {
171     return buffer_.str();
172   }
173 
174  private:
175   std::ostringstream buffer_;
176   const char* const file_;
177   const unsigned int line_number_;
178   const LogSeverity severity_;
179   const int error_;
180 
181   DISALLOW_COPY_AND_ASSIGN(LogMessageData);
182 };
183 
184 
LogMessage(const char * file,unsigned int line,LogSeverity severity,int error)185 LogMessage::LogMessage(const char* file, unsigned int line, LogSeverity severity, int error)
186   : data_(new LogMessageData(file, line, severity, error)) {
187   if (PrintDirectly(severity)) {
188     static constexpr char kLogCharacters[] = { 'N', 'V', 'D', 'I', 'W', 'E', 'F', 'F' };
189     static_assert(arraysize(kLogCharacters) == static_cast<size_t>(INTERNAL_FATAL) + 1,
190                   "Wrong character array size");
191     stream() << ProgramInvocationShortName() << " " << kLogCharacters[static_cast<size_t>(severity)]
192              << " " << getpid() << " " << ::art::GetTid() << " " << file << ":" <<  line << "]";
193   }
194 }
~LogMessage()195 LogMessage::~LogMessage() {
196   if (!PrintDirectly(data_->GetSeverity()) && data_->GetSeverity() != LogSeverity::NONE) {
197     if (data_->GetSeverity() < gMinimumLogSeverity) {
198       return;  // No need to format something we're not going to output.
199     }
200 
201     // Finish constructing the message.
202     if (data_->GetError() != -1) {
203       data_->GetBuffer() << ": " << strerror(data_->GetError());
204     }
205     std::string msg(data_->ToString());
206 
207     // Do the actual logging with the lock held.
208     {
209       MutexLock mu(Thread::Current(), *Locks::logging_lock_);
210       if (msg.find('\n') == std::string::npos) {
211         LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetSeverity(), msg.c_str());
212       } else {
213         msg += '\n';
214         size_t i = 0;
215         while (i < msg.size()) {
216           size_t nl = msg.find('\n', i);
217           msg[nl] = '\0';
218           LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetSeverity(), &msg[i]);
219           i = nl + 1;
220         }
221       }
222     }
223   }
224 
225   // Abort if necessary.
226   if (data_->GetSeverity() == FATAL) {
227     Runtime::Abort();
228   }
229 }
230 
stream()231 std::ostream& LogMessage::stream() {
232   if (PrintDirectly(data_->GetSeverity())) {
233     return std::cerr;
234   }
235   return data_->GetBuffer();
236 }
237 
238 #ifdef __ANDROID__
239 static const android_LogPriority kLogSeverityToAndroidLogPriority[] = {
240   ANDROID_LOG_VERBOSE,  // NONE, use verbose as stand-in, will never be printed.
241   ANDROID_LOG_VERBOSE, ANDROID_LOG_DEBUG, ANDROID_LOG_INFO, ANDROID_LOG_WARN,
242   ANDROID_LOG_ERROR, ANDROID_LOG_FATAL, ANDROID_LOG_FATAL
243 };
244 static_assert(arraysize(kLogSeverityToAndroidLogPriority) == INTERNAL_FATAL + 1,
245               "Mismatch in size of kLogSeverityToAndroidLogPriority and values in LogSeverity");
246 #endif
247 
LogLine(const char * file,unsigned int line,LogSeverity log_severity,const char * message)248 void LogMessage::LogLine(const char* file, unsigned int line, LogSeverity log_severity,
249                          const char* message) {
250   if (log_severity == LogSeverity::NONE) {
251     return;
252   }
253 
254 #ifdef __ANDROID__
255   const char* tag = ProgramInvocationShortName();
256   int priority = kLogSeverityToAndroidLogPriority[static_cast<size_t>(log_severity)];
257   if (priority == ANDROID_LOG_FATAL) {
258     LOG_PRI(priority, tag, "%s:%u] %s", file, line, message);
259   } else {
260     LOG_PRI(priority, tag, "%s", message);
261   }
262 #else
263   static const char* log_characters = "NVDIWEFF";
264   CHECK_EQ(strlen(log_characters), INTERNAL_FATAL + 1U);
265   char severity = log_characters[log_severity];
266   fprintf(stderr, "%s %c %5d %5d %s:%u] %s\n",
267           ProgramInvocationShortName(), severity, getpid(), ::art::GetTid(), file, line, message);
268 #endif
269 }
270 
LogLineLowStack(const char * file,unsigned int line,LogSeverity log_severity,const char * message)271 void LogMessage::LogLineLowStack(const char* file, unsigned int line, LogSeverity log_severity,
272                                  const char* message) {
273   if (log_severity == LogSeverity::NONE) {
274     return;
275   }
276 
277 #ifdef __ANDROID__
278   // Use android_writeLog() to avoid stack-based buffers used by android_printLog().
279   const char* tag = ProgramInvocationShortName();
280   int priority = kLogSeverityToAndroidLogPriority[static_cast<size_t>(log_severity)];
281   char* buf = nullptr;
282   size_t buf_size = 0u;
283   if (priority == ANDROID_LOG_FATAL) {
284     // Allocate buffer for snprintf(buf, buf_size, "%s:%u] %s", file, line, message) below.
285     // If allocation fails, fall back to printing only the message.
286     buf_size = strlen(file) + 1 /* ':' */ + std::numeric_limits<typeof(line)>::max_digits10 +
287         2 /* "] " */ + strlen(message) + 1 /* terminating 0 */;
288     buf = reinterpret_cast<char*>(malloc(buf_size));
289   }
290   if (buf != nullptr) {
291     snprintf(buf, buf_size, "%s:%u] %s", file, line, message);
292     android_writeLog(priority, tag, buf);
293     free(buf);
294   } else {
295     android_writeLog(priority, tag, message);
296   }
297 #else
298   static constexpr char kLogCharacters[] = { 'N', 'V', 'D', 'I', 'W', 'E', 'F', 'F' };
299   static_assert(arraysize(kLogCharacters) == static_cast<size_t>(INTERNAL_FATAL) + 1,
300                 "Wrong character array size");
301 
302   const char* program_name = ProgramInvocationShortName();
303   TEMP_FAILURE_RETRY(write(STDERR_FILENO, program_name, strlen(program_name)));
304   TEMP_FAILURE_RETRY(write(STDERR_FILENO, " ", 1));
305   TEMP_FAILURE_RETRY(write(STDERR_FILENO, &kLogCharacters[static_cast<size_t>(log_severity)], 1));
306   TEMP_FAILURE_RETRY(write(STDERR_FILENO, " ", 1));
307   // TODO: pid and tid.
308   TEMP_FAILURE_RETRY(write(STDERR_FILENO, file, strlen(file)));
309   // TODO: line.
310   UNUSED(line);
311   TEMP_FAILURE_RETRY(write(STDERR_FILENO, "] ", 2));
312   TEMP_FAILURE_RETRY(write(STDERR_FILENO, message, strlen(message)));
313   TEMP_FAILURE_RETRY(write(STDERR_FILENO, "\n", 1));
314 #endif
315 }
316 
ScopedLogSeverity(LogSeverity level)317 ScopedLogSeverity::ScopedLogSeverity(LogSeverity level) {
318   old_ = gMinimumLogSeverity;
319   gMinimumLogSeverity = level;
320 }
321 
~ScopedLogSeverity()322 ScopedLogSeverity::~ScopedLogSeverity() {
323   gMinimumLogSeverity = old_;
324 }
325 
326 }  // namespace art
327