logging.h revision 5fd66d0546805f0d86ec3365762c00b8dd3415f5 
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#ifndef ART_RUNTIME_BASE_LOGGING_H_
18#define ART_RUNTIME_BASE_LOGGING_H_
19
20#include <ostream>
21
22#include "base/macros.h"
23
24namespace art {
25
26enum LogSeverity {
27  VERBOSE,
28  DEBUG,
29  INFO,
30  WARNING,
31  ERROR,
32  FATAL,
33  INTERNAL_FATAL,  // For Runtime::Abort.
34};
35
36// The members of this struct are the valid arguments to VLOG and VLOG_IS_ON in code,
37// and the "-verbose:" command line argument.
38struct LogVerbosity {
39  bool class_linker;  // Enabled with "-verbose:class".
40  bool collector;
41  bool compiler;
42  bool deopt;
43  bool gc;
44  bool heap;
45  bool jdwp;
46  bool jit;
47  bool jni;
48  bool monitor;
49  bool oat;
50  bool profiler;
51  bool signals;
52  bool simulator;
53  bool startup;
54  bool third_party_jni;  // Enabled with "-verbose:third-party-jni".
55  bool threads;
56  bool verifier;
57  bool image;
58  bool systrace_lock_logging;  // Enabled with "-verbose:sys-locks".
59  bool agents;
60};
61
62// Global log verbosity setting, initialized by InitLogging.
63extern LogVerbosity gLogVerbosity;
64
65// 0 if not abort, non-zero if an abort is in progress. Used on fatal exit to prevents recursive
66// aborts. Global declaration allows us to disable some error checking to ensure fatal shutdown
67// makes forward progress.
68extern unsigned int gAborting;
69
70// Configure logging based on ANDROID_LOG_TAGS environment variable.
71// We need to parse a string that looks like
72//
73//      *:v jdwp:d dalvikvm:d dalvikvm-gc:i dalvikvmi:i
74//
75// The tag (or '*' for the global level) comes first, followed by a colon
76// and a letter indicating the minimum priority level we're expected to log.
77// This can be used to reveal or conceal logs with specific tags.
78extern void InitLogging(char* argv[]);
79
80// Returns the command line used to invoke the current tool or null if InitLogging hasn't been
81// performed.
82extern const char* GetCmdLine();
83
84// The command used to start the ART runtime, such as "/system/bin/dalvikvm". If InitLogging hasn't
85// been performed then just returns "art"
86extern const char* ProgramInvocationName();
87
88// A short version of the command used to start the ART runtime, such as "dalvikvm". If InitLogging
89// hasn't been performed then just returns "art"
90extern const char* ProgramInvocationShortName();
91
92// Logs a message to logcat on Android otherwise to stderr. If the severity is FATAL it also causes
93// an abort. For example: LOG(FATAL) << "We didn't expect to reach here";
94#define LOG(severity) ::art::LogMessage(__FILE__, __LINE__, severity, -1).stream()
95
96// A variant of LOG that also logs the current errno value. To be used when library calls fail.
97#define PLOG(severity) ::art::LogMessage(__FILE__, __LINE__, severity, errno).stream()
98
99// Marker that code is yet to be implemented.
100#define UNIMPLEMENTED(level) LOG(level) << __PRETTY_FUNCTION__ << " unimplemented "
101
102// Is verbose logging enabled for the given module? Where the module is defined in LogVerbosity.
103#define VLOG_IS_ON(module) UNLIKELY(::art::gLogVerbosity.module)
104
105// Variant of LOG that logs when verbose logging is enabled for a module. For example,
106// VLOG(jni) << "A JNI operation was performed";
107#define VLOG(module) \
108  if (VLOG_IS_ON(module)) \
109    ::art::LogMessage(__FILE__, __LINE__, INFO, -1).stream()
110
111// Return the stream associated with logging for the given module.
112#define VLOG_STREAM(module) ::art::LogMessage(__FILE__, __LINE__, INFO, -1).stream()
113
114// Check whether condition x holds and LOG(FATAL) if not. The value of the expression x is only
115// evaluated once. Extra logging can be appended using << after. For example,
116// CHECK(false == true) results in a log message of "Check failed: false == true".
117#define CHECK(x) \
118  if (UNLIKELY(!(x))) \
119    ::art::LogMessage(__FILE__, __LINE__, ::art::FATAL, -1).stream() \
120        << "Check failed: " #x << " "
121
122// Helper for CHECK_xx(x,y) macros.
123#define CHECK_OP(LHS, RHS, OP) \
124  for (auto _values = ::art::MakeEagerEvaluator(LHS, RHS); \
125       UNLIKELY(!(_values.lhs OP _values.rhs)); /* empty */) \
126    ::art::LogMessage(__FILE__, __LINE__, ::art::FATAL, -1).stream() \
127        << "Check failed: " << #LHS << " " << #OP << " " << #RHS \
128        << " (" #LHS "=" << _values.lhs << ", " #RHS "=" << _values.rhs << ") "
129
130
131// Check whether a condition holds between x and y, LOG(FATAL) if not. The value of the expressions
132// x and y is evaluated once. Extra logging can be appended using << after. For example,
133// CHECK_NE(0 == 1, false) results in "Check failed: false != false (0==1=false, false=false) ".
134#define CHECK_EQ(x, y) CHECK_OP(x, y, ==)
135#define CHECK_NE(x, y) CHECK_OP(x, y, !=)
136#define CHECK_LE(x, y) CHECK_OP(x, y, <=)
137#define CHECK_LT(x, y) CHECK_OP(x, y, <)
138#define CHECK_GE(x, y) CHECK_OP(x, y, >=)
139#define CHECK_GT(x, y) CHECK_OP(x, y, >)
140
141// Helper for CHECK_STRxx(s1,s2) macros.
142#define CHECK_STROP(s1, s2, sense) \
143  if (UNLIKELY((strcmp(s1, s2) == 0) != (sense))) \
144    LOG(::art::FATAL) << "Check failed: " \
145        << "\"" << (s1) << "\"" \
146        << ((sense) ? " == " : " != ") \
147        << "\"" << (s2) << "\""
148
149// Check for string (const char*) equality between s1 and s2, LOG(FATAL) if not.
150#define CHECK_STREQ(s1, s2) CHECK_STROP(s1, s2, true)
151#define CHECK_STRNE(s1, s2) CHECK_STROP(s1, s2, false)
152
153// Perform the pthread function call(args), LOG(FATAL) on error.
154#define CHECK_PTHREAD_CALL(call, args, what) \
155  do { \
156    int rc = call args; \
157    if (rc != 0) { \
158      errno = rc; \
159      PLOG(::art::FATAL) << # call << " failed for " << (what); \
160    } \
161  } while (false)
162
163
164// DCHECKs are debug variants of CHECKs only enabled in debug builds. Generally CHECK should be
165// used unless profiling identifies a CHECK as being in performance critical code.
166#if defined(NDEBUG)
167static constexpr bool kEnableDChecks = false;
168#else
169static constexpr bool kEnableDChecks = true;
170#endif
171
172#define DCHECK(x) if (::art::kEnableDChecks) CHECK(x)
173#define DCHECK_EQ(x, y) if (::art::kEnableDChecks) CHECK_EQ(x, y)
174#define DCHECK_NE(x, y) if (::art::kEnableDChecks) CHECK_NE(x, y)
175#define DCHECK_LE(x, y) if (::art::kEnableDChecks) CHECK_LE(x, y)
176#define DCHECK_LT(x, y) if (::art::kEnableDChecks) CHECK_LT(x, y)
177#define DCHECK_GE(x, y) if (::art::kEnableDChecks) CHECK_GE(x, y)
178#define DCHECK_GT(x, y) if (::art::kEnableDChecks) CHECK_GT(x, y)
179#define DCHECK_STREQ(s1, s2) if (::art::kEnableDChecks) CHECK_STREQ(s1, s2)
180#define DCHECK_STRNE(s1, s2) if (::art::kEnableDChecks) CHECK_STRNE(s1, s2)
181
182// Temporary class created to evaluate the LHS and RHS, used with MakeEagerEvaluator to infer the
183// types of LHS and RHS.
184template <typename LHS, typename RHS>
185struct EagerEvaluator {
186  constexpr EagerEvaluator(LHS l, RHS r) : lhs(l), rhs(r) { }
187  LHS lhs;
188  RHS rhs;
189};
190
191// Helper function for CHECK_xx.
192template <typename LHS, typename RHS>
193constexpr EagerEvaluator<LHS, RHS> MakeEagerEvaluator(LHS lhs, RHS rhs) {
194  return EagerEvaluator<LHS, RHS>(lhs, rhs);
195}
196
197// Explicitly instantiate EagerEvalue for pointers so that char*s aren't treated as strings. To
198// compare strings use CHECK_STREQ and CHECK_STRNE. We rely on signed/unsigned warnings to
199// protect you against combinations not explicitly listed below.
200#define EAGER_PTR_EVALUATOR(T1, T2) \
201  template <> struct EagerEvaluator<T1, T2> { \
202    EagerEvaluator(T1 l, T2 r) \
203        : lhs(reinterpret_cast<const void*>(l)), \
204          rhs(reinterpret_cast<const void*>(r)) { } \
205    const void* lhs; \
206    const void* rhs; \
207  }
208EAGER_PTR_EVALUATOR(const char*, const char*);
209EAGER_PTR_EVALUATOR(const char*, char*);
210EAGER_PTR_EVALUATOR(char*, const char*);
211EAGER_PTR_EVALUATOR(char*, char*);
212EAGER_PTR_EVALUATOR(const unsigned char*, const unsigned char*);
213EAGER_PTR_EVALUATOR(const unsigned char*, unsigned char*);
214EAGER_PTR_EVALUATOR(unsigned char*, const unsigned char*);
215EAGER_PTR_EVALUATOR(unsigned char*, unsigned char*);
216EAGER_PTR_EVALUATOR(const signed char*, const signed char*);
217EAGER_PTR_EVALUATOR(const signed char*, signed char*);
218EAGER_PTR_EVALUATOR(signed char*, const signed char*);
219EAGER_PTR_EVALUATOR(signed char*, signed char*);
220
221// Data for the log message, not stored in LogMessage to avoid increasing the stack size.
222class LogMessageData;
223
224// A LogMessage is a temporarily scoped object used by LOG and the unlikely part of a CHECK. The
225// destructor will abort if the severity is FATAL.
226class LogMessage {
227 public:
228  LogMessage(const char* file, unsigned int line, LogSeverity severity, int error);
229
230  ~LogMessage();  // TODO: enable REQUIRES(!Locks::logging_lock_).
231
232  // Returns the stream associated with the message, the LogMessage performs output when it goes
233  // out of scope.
234  std::ostream& stream();
235
236  // The routine that performs the actual logging.
237  static void LogLine(const char* file, unsigned int line, LogSeverity severity, const char* msg);
238
239  // A variant of the above for use with little stack.
240  static void LogLineLowStack(const char* file, unsigned int line, LogSeverity severity,
241                              const char* msg);
242
243 private:
244  const std::unique_ptr<LogMessageData> data_;
245
246  DISALLOW_COPY_AND_ASSIGN(LogMessage);
247};
248
249// Allows to temporarily change the minimum severity level for logging.
250class ScopedLogSeverity {
251 public:
252  explicit ScopedLogSeverity(LogSeverity level);
253  ~ScopedLogSeverity();
254
255 private:
256  LogSeverity old_;
257};
258
259}  // namespace art
260
261#endif  // ART_RUNTIME_BASE_LOGGING_H_
262