logging.h revision cf7f19135f0e273f7b0136315633c2abfc715343 
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 <memory>
21#include <ostream>
22
23#include "base/macros.h"
24
25namespace art {
26
27enum LogSeverity {
28  VERBOSE,
29  DEBUG,
30  INFO,
31  WARNING,
32  ERROR,
33  FATAL,
34  INTERNAL_FATAL,  // For Runtime::Abort.
35};
36
37// The members of this struct are the valid arguments to VLOG and VLOG_IS_ON in code,
38// and the "-verbose:" command line argument.
39struct LogVerbosity {
40  bool class_linker;  // Enabled with "-verbose:class".
41  bool compiler;
42  bool gc;
43  bool heap;
44  bool jdwp;
45  bool jni;
46  bool monitor;
47  bool profiler;
48  bool signals;
49  bool startup;
50  bool third_party_jni;  // Enabled with "-verbose:third-party-jni".
51  bool threads;
52  bool verifier;
53};
54
55// Global log verbosity setting, initialized by InitLogging.
56extern LogVerbosity gLogVerbosity;
57
58// 0 if not abort, non-zero if an abort is in progress. Used on fatal exit to prevents recursive
59// aborts. Global declaration allows us to disable some error checking to ensure fatal shutdown
60// makes forward progress.
61extern unsigned int gAborting;
62
63// Configure logging based on ANDROID_LOG_TAGS environment variable.
64// We need to parse a string that looks like
65//
66//      *:v jdwp:d dalvikvm:d dalvikvm-gc:i dalvikvmi:i
67//
68// The tag (or '*' for the global level) comes first, followed by a colon
69// and a letter indicating the minimum priority level we're expected to log.
70// This can be used to reveal or conceal logs with specific tags.
71extern void InitLogging(char* argv[]);
72
73// Returns the command line used to invoke the current tool or nullptr if InitLogging hasn't been
74// performed.
75extern const char* GetCmdLine();
76
77// The command used to start the ART runtime, such as "/system/bin/dalvikvm". If InitLogging hasn't
78// been performed then just returns "art"
79extern const char* ProgramInvocationName();
80
81// A short version of the command used to start the ART runtime, such as "dalvikvm". If InitLogging
82// hasn't been performed then just returns "art"
83extern const char* ProgramInvocationShortName();
84
85// Logs a message to logcat on Android otherwise to stderr. If the severity is FATAL it also causes
86// an abort. For example: LOG(FATAL) << "We didn't expect to reach here";
87#define LOG(severity) ::art::LogMessage(__FILE__, __LINE__, severity, -1).stream()
88
89// A variant of LOG that also logs the current errno value. To be used when library calls fail.
90#define PLOG(severity) ::art::LogMessage(__FILE__, __LINE__, severity, errno).stream()
91
92// Marker that code is yet to be implemented.
93#define UNIMPLEMENTED(level) LOG(level) << __PRETTY_FUNCTION__ << " unimplemented "
94
95// Is verbose logging enabled for the given module? Where the module is defined in LogVerbosity.
96#define VLOG_IS_ON(module) UNLIKELY(::art::gLogVerbosity.module)
97
98// Variant of LOG that logs when verbose logging is enabled for a module. For example,
99// VLOG(jni) << "A JNI operation was performed";
100#define VLOG(module) \
101  if (VLOG_IS_ON(module)) \
102    ::art::LogMessage(__FILE__, __LINE__, INFO, -1).stream()
103
104// Return the stream associated with logging for the given module.
105#define VLOG_STREAM(module) ::art::LogMessage(__FILE__, __LINE__, INFO, -1).stream()
106
107// Check whether condition x holds and LOG(FATAL) if not. The value of the expression x is only
108// evaluated once. Extra logging can be appended using << after. For example,
109// CHECK(false == true) results in a log message of "Check failed: false == true".
110#define CHECK(x) \
111  if (UNLIKELY(!(x))) \
112    ::art::LogMessage(__FILE__, __LINE__, ::art::FATAL, -1).stream() \
113        << "Check failed: " #x << " "
114
115// Helper for CHECK_xx(x,y) macros.
116#define CHECK_OP(LHS, RHS, OP) \
117  for (auto _values = ::art::MakeEagerEvaluator(LHS, RHS); \
118       UNLIKELY(!(_values.lhs OP _values.rhs)); /* empty */) \
119    ::art::LogMessage(__FILE__, __LINE__, ::art::FATAL, -1).stream() \
120        << "Check failed: " << #LHS << " " << #OP << " " << #RHS \
121        << " (" #LHS "=" << _values.lhs << ", " #RHS "=" << _values.rhs << ") "
122
123
124// Check whether a condition holds between x and y, LOG(FATAL) if not. The value of the expressions
125// x and y is evaluated once. Extra logging can be appended using << after. For example,
126// CHECK_NE(0 == 1, false) results in "Check failed: false != false (0==1=false, false=false) ".
127#define CHECK_EQ(x, y) CHECK_OP(x, y, ==)
128#define CHECK_NE(x, y) CHECK_OP(x, y, !=)
129#define CHECK_LE(x, y) CHECK_OP(x, y, <=)
130#define CHECK_LT(x, y) CHECK_OP(x, y, <)
131#define CHECK_GE(x, y) CHECK_OP(x, y, >=)
132#define CHECK_GT(x, y) CHECK_OP(x, y, >)
133
134// Helper for CHECK_STRxx(s1,s2) macros.
135#define CHECK_STROP(s1, s2, sense) \
136  if (UNLIKELY((strcmp(s1, s2) == 0) != sense)) \
137    LOG(::art::FATAL) << "Check failed: " \
138        << "\"" << s1 << "\"" \
139        << (sense ? " == " : " != ") \
140        << "\"" << s2 << "\""
141
142// Check for string (const char*) equality between s1 and s2, LOG(FATAL) if not.
143#define CHECK_STREQ(s1, s2) CHECK_STROP(s1, s2, true)
144#define CHECK_STRNE(s1, s2) CHECK_STROP(s1, s2, false)
145
146// Perform the pthread function call(args), LOG(FATAL) on error.
147#define CHECK_PTHREAD_CALL(call, args, what) \
148  do { \
149    int rc = call args; \
150    if (rc != 0) { \
151      errno = rc; \
152      PLOG(::art::FATAL) << # call << " failed for " << what; \
153    } \
154  } while (false)
155
156// CHECK that can be used in a constexpr function. For example,
157//    constexpr int half(int n) {
158//      return
159//          DCHECK_CONSTEXPR(n >= 0, , 0)
160//          CHECK_CONSTEXPR((n & 1) == 0), << "Extra debugging output: n = " << n, 0)
161//          n / 2;
162//    }
163#define CHECK_CONSTEXPR(x, out, dummy) \
164  (UNLIKELY(!(x))) ? (LOG(::art::FATAL) << "Check failed: " << #x out, dummy) :
165
166
167// DCHECKs are debug variants of CHECKs only enabled in debug builds. Generally CHECK should be
168// used unless profiling identifies a CHECK as being in performance critical code.
169#if defined(NDEBUG)
170static constexpr bool kEnableDChecks = false;
171#else
172static constexpr bool kEnableDChecks = true;
173#endif
174
175#define DCHECK(x) if (::art::kEnableDChecks) CHECK(x)
176#define DCHECK_EQ(x, y) if (::art::kEnableDChecks) CHECK_EQ(x, y)
177#define DCHECK_NE(x, y) if (::art::kEnableDChecks) CHECK_NE(x, y)
178#define DCHECK_LE(x, y) if (::art::kEnableDChecks) CHECK_LE(x, y)
179#define DCHECK_LT(x, y) if (::art::kEnableDChecks) CHECK_LT(x, y)
180#define DCHECK_GE(x, y) if (::art::kEnableDChecks) CHECK_GE(x, y)
181#define DCHECK_GT(x, y) if (::art::kEnableDChecks) CHECK_GT(x, y)
182#define DCHECK_STREQ(s1, s2) if (::art::kEnableDChecks) CHECK_STREQ(s1, s2)
183#define DCHECK_STRNE(s1, s2) if (::art::kEnableDChecks) CHECK_STRNE(s1, s2)
184#if defined(NDEBUG)
185#define DCHECK_CONSTEXPR(x, out, dummy)
186#else
187#define DCHECK_CONSTEXPR(x, out, dummy) CHECK_CONSTEXPR(x, out, dummy)
188#endif
189
190// Temporary class created to evaluate the LHS and RHS, used with MakeEagerEvaluator to infer the
191// types of LHS and RHS.
192template <typename LHS, typename RHS>
193struct EagerEvaluator {
194  EagerEvaluator(LHS l, RHS r) : lhs(l), rhs(r) { }
195  LHS lhs;
196  RHS rhs;
197};
198
199// Helper function for CHECK_xx.
200template <typename LHS, typename RHS>
201static inline EagerEvaluator<LHS, RHS> MakeEagerEvaluator(LHS lhs, RHS rhs) {
202  return EagerEvaluator<LHS, RHS>(lhs, rhs);
203}
204
205// Explicitly instantiate EagerEvalue for pointers so that char*s aren't treated as strings. To
206// compare strings use CHECK_STREQ and CHECK_STRNE. We rely on signed/unsigned warnings to
207// protect you against combinations not explicitly listed below.
208#define EAGER_PTR_EVALUATOR(T1, T2) \
209  template <> struct EagerEvaluator<T1, T2> { \
210    EagerEvaluator(T1 l, T2 r) \
211        : lhs(reinterpret_cast<const void*>(l)), \
212          rhs(reinterpret_cast<const void*>(r)) { } \
213    const void* lhs; \
214    const void* rhs; \
215  }
216EAGER_PTR_EVALUATOR(const char*, const char*);
217EAGER_PTR_EVALUATOR(const char*, char*);
218EAGER_PTR_EVALUATOR(char*, const char*);
219EAGER_PTR_EVALUATOR(char*, char*);
220EAGER_PTR_EVALUATOR(const unsigned char*, const unsigned char*);
221EAGER_PTR_EVALUATOR(const unsigned char*, unsigned char*);
222EAGER_PTR_EVALUATOR(unsigned char*, const unsigned char*);
223EAGER_PTR_EVALUATOR(unsigned char*, unsigned char*);
224EAGER_PTR_EVALUATOR(const signed char*, const signed char*);
225EAGER_PTR_EVALUATOR(const signed char*, signed char*);
226EAGER_PTR_EVALUATOR(signed char*, const signed char*);
227EAGER_PTR_EVALUATOR(signed char*, signed char*);
228
229// Data for the log message, not stored in LogMessage to avoid increasing the stack size.
230class LogMessageData;
231
232// A LogMessage is a temporarily scoped object used by LOG and the unlikely part of a CHECK. The
233// destructor will abort if the severity is FATAL.
234class LogMessage {
235 public:
236  LogMessage(const char* file, unsigned int line, LogSeverity severity, int error);
237
238  ~LogMessage();  // TODO: enable LOCKS_EXCLUDED(Locks::logging_lock_).
239
240  // Returns the stream associated with the message, the LogMessage performs output when it goes
241  // out of scope.
242  std::ostream& stream();
243
244  // The routine that performs the actual logging.
245  static void LogLine(const char* file, unsigned int line, LogSeverity severity, const char* msg);
246
247 private:
248  const std::unique_ptr<LogMessageData> data_;
249
250  DISALLOW_COPY_AND_ASSIGN(LogMessage);
251};
252
253}  // namespace art
254
255#endif  // ART_RUNTIME_BASE_LOGGING_H_
256