logging.h revision 1bc977cf2f8199311a97f2ba9431a184540e3e9c 
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 compiler;
41  bool deopt;
42  bool gc;
43  bool heap;
44  bool jdwp;
45  bool jit;
46  bool jni;
47  bool monitor;
48  bool oat;
49  bool profiler;
50  bool signals;
51  bool simulator;
52  bool startup;
53  bool third_party_jni;  // Enabled with "-verbose:third-party-jni".
54  bool threads;
55  bool verifier;
56};
57
58// Global log verbosity setting, initialized by InitLogging.
59extern LogVerbosity gLogVerbosity;
60
61// 0 if not abort, non-zero if an abort is in progress. Used on fatal exit to prevents recursive
62// aborts. Global declaration allows us to disable some error checking to ensure fatal shutdown
63// makes forward progress.
64extern unsigned int gAborting;
65
66// Configure logging based on ANDROID_LOG_TAGS environment variable.
67// We need to parse a string that looks like
68//
69//      *:v jdwp:d dalvikvm:d dalvikvm-gc:i dalvikvmi:i
70//
71// The tag (or '*' for the global level) comes first, followed by a colon
72// and a letter indicating the minimum priority level we're expected to log.
73// This can be used to reveal or conceal logs with specific tags.
74extern void InitLogging(char* argv[]);
75
76// Returns the command line used to invoke the current tool or null if InitLogging hasn't been
77// performed.
78extern const char* GetCmdLine();
79
80// The command used to start the ART runtime, such as "/system/bin/dalvikvm". If InitLogging hasn't
81// been performed then just returns "art"
82extern const char* ProgramInvocationName();
83
84// A short version of the command used to start the ART runtime, such as "dalvikvm". If InitLogging
85// hasn't been performed then just returns "art"
86extern const char* ProgramInvocationShortName();
87
88// Logs a message to logcat on Android otherwise to stderr. If the severity is FATAL it also causes
89// an abort. For example: LOG(FATAL) << "We didn't expect to reach here";
90#define LOG(severity) ::art::LogMessage(__FILE__, __LINE__, severity, -1).stream()
91
92// A variant of LOG that also logs the current errno value. To be used when library calls fail.
93#define PLOG(severity) ::art::LogMessage(__FILE__, __LINE__, severity, errno).stream()
94
95// Marker that code is yet to be implemented.
96#define UNIMPLEMENTED(level) LOG(level) << __PRETTY_FUNCTION__ << " unimplemented "
97
98// Is verbose logging enabled for the given module? Where the module is defined in LogVerbosity.
99#define VLOG_IS_ON(module) UNLIKELY(::art::gLogVerbosity.module)
100
101// Variant of LOG that logs when verbose logging is enabled for a module. For example,
102// VLOG(jni) << "A JNI operation was performed";
103#define VLOG(module) \
104  if (VLOG_IS_ON(module)) \
105    ::art::LogMessage(__FILE__, __LINE__, INFO, -1).stream()
106
107// Return the stream associated with logging for the given module.
108#define VLOG_STREAM(module) ::art::LogMessage(__FILE__, __LINE__, INFO, -1).stream()
109
110// Check whether condition x holds and LOG(FATAL) if not. The value of the expression x is only
111// evaluated once. Extra logging can be appended using << after. For example,
112// CHECK(false == true) results in a log message of "Check failed: false == true".
113#define CHECK(x) \
114  if (UNLIKELY(!(x))) \
115    ::art::LogMessage(__FILE__, __LINE__, ::art::FATAL, -1).stream() \
116        << "Check failed: " #x << " "
117
118// Helper for CHECK_xx(x,y) macros.
119#define CHECK_OP(LHS, RHS, OP) \
120  for (auto _values = ::art::MakeEagerEvaluator(LHS, RHS); \
121       UNLIKELY(!(_values.lhs OP _values.rhs)); /* empty */) \
122    ::art::LogMessage(__FILE__, __LINE__, ::art::FATAL, -1).stream() \
123        << "Check failed: " << #LHS << " " << #OP << " " << #RHS \
124        << " (" #LHS "=" << _values.lhs << ", " #RHS "=" << _values.rhs << ") "
125
126
127// Check whether a condition holds between x and y, LOG(FATAL) if not. The value of the expressions
128// x and y is evaluated once. Extra logging can be appended using << after. For example,
129// CHECK_NE(0 == 1, false) results in "Check failed: false != false (0==1=false, false=false) ".
130#define CHECK_EQ(x, y) CHECK_OP(x, y, ==)
131#define CHECK_NE(x, y) CHECK_OP(x, y, !=)
132#define CHECK_LE(x, y) CHECK_OP(x, y, <=)
133#define CHECK_LT(x, y) CHECK_OP(x, y, <)
134#define CHECK_GE(x, y) CHECK_OP(x, y, >=)
135#define CHECK_GT(x, y) CHECK_OP(x, y, >)
136
137// Helper for CHECK_STRxx(s1,s2) macros.
138#define CHECK_STROP(s1, s2, sense) \
139  if (UNLIKELY((strcmp(s1, s2) == 0) != sense)) \
140    LOG(::art::FATAL) << "Check failed: " \
141        << "\"" << s1 << "\"" \
142        << (sense ? " == " : " != ") \
143        << "\"" << s2 << "\""
144
145// Check for string (const char*) equality between s1 and s2, LOG(FATAL) if not.
146#define CHECK_STREQ(s1, s2) CHECK_STROP(s1, s2, true)
147#define CHECK_STRNE(s1, s2) CHECK_STROP(s1, s2, false)
148
149// Perform the pthread function call(args), LOG(FATAL) on error.
150#define CHECK_PTHREAD_CALL(call, args, what) \
151  do { \
152    int rc = call args; \
153    if (rc != 0) { \
154      errno = rc; \
155      PLOG(::art::FATAL) << # call << " failed for " << what; \
156    } \
157  } while (false)
158
159// CHECK that can be used in a constexpr function. For example,
160//    constexpr int half(int n) {
161//      return
162//          DCHECK_CONSTEXPR(n >= 0, , 0)
163//          CHECK_CONSTEXPR((n & 1) == 0), << "Extra debugging output: n = " << n, 0)
164//          n / 2;
165//    }
166#define CHECK_CONSTEXPR(x, out, dummy) \
167  (UNLIKELY(!(x))) ? (LOG(::art::FATAL) << "Check failed: " << #x out, dummy) :
168
169
170// DCHECKs are debug variants of CHECKs only enabled in debug builds. Generally CHECK should be
171// used unless profiling identifies a CHECK as being in performance critical code.
172#if defined(NDEBUG)
173static constexpr bool kEnableDChecks = false;
174#else
175static constexpr bool kEnableDChecks = true;
176#endif
177
178#define DCHECK(x) if (::art::kEnableDChecks) CHECK(x)
179#define DCHECK_EQ(x, y) if (::art::kEnableDChecks) CHECK_EQ(x, y)
180#define DCHECK_NE(x, y) if (::art::kEnableDChecks) CHECK_NE(x, y)
181#define DCHECK_LE(x, y) if (::art::kEnableDChecks) CHECK_LE(x, y)
182#define DCHECK_LT(x, y) if (::art::kEnableDChecks) CHECK_LT(x, y)
183#define DCHECK_GE(x, y) if (::art::kEnableDChecks) CHECK_GE(x, y)
184#define DCHECK_GT(x, y) if (::art::kEnableDChecks) CHECK_GT(x, y)
185#define DCHECK_STREQ(s1, s2) if (::art::kEnableDChecks) CHECK_STREQ(s1, s2)
186#define DCHECK_STRNE(s1, s2) if (::art::kEnableDChecks) CHECK_STRNE(s1, s2)
187#if defined(NDEBUG)
188#define DCHECK_CONSTEXPR(x, out, dummy)
189#else
190#define DCHECK_CONSTEXPR(x, out, dummy) CHECK_CONSTEXPR(x, out, dummy)
191#endif
192
193// Temporary class created to evaluate the LHS and RHS, used with MakeEagerEvaluator to infer the
194// types of LHS and RHS.
195template <typename LHS, typename RHS>
196struct EagerEvaluator {
197  EagerEvaluator(LHS l, RHS r) : lhs(l), rhs(r) { }
198  LHS lhs;
199  RHS rhs;
200};
201
202// Helper function for CHECK_xx.
203template <typename LHS, typename RHS>
204static inline EagerEvaluator<LHS, RHS> MakeEagerEvaluator(LHS lhs, RHS rhs) {
205  return EagerEvaluator<LHS, RHS>(lhs, rhs);
206}
207
208// Explicitly instantiate EagerEvalue for pointers so that char*s aren't treated as strings. To
209// compare strings use CHECK_STREQ and CHECK_STRNE. We rely on signed/unsigned warnings to
210// protect you against combinations not explicitly listed below.
211#define EAGER_PTR_EVALUATOR(T1, T2) \
212  template <> struct EagerEvaluator<T1, T2> { \
213    EagerEvaluator(T1 l, T2 r) \
214        : lhs(reinterpret_cast<const void*>(l)), \
215          rhs(reinterpret_cast<const void*>(r)) { } \
216    const void* lhs; \
217    const void* rhs; \
218  }
219EAGER_PTR_EVALUATOR(const char*, const char*);
220EAGER_PTR_EVALUATOR(const char*, char*);
221EAGER_PTR_EVALUATOR(char*, const char*);
222EAGER_PTR_EVALUATOR(char*, char*);
223EAGER_PTR_EVALUATOR(const unsigned char*, const unsigned char*);
224EAGER_PTR_EVALUATOR(const unsigned char*, unsigned char*);
225EAGER_PTR_EVALUATOR(unsigned char*, const unsigned char*);
226EAGER_PTR_EVALUATOR(unsigned char*, unsigned char*);
227EAGER_PTR_EVALUATOR(const signed char*, const signed char*);
228EAGER_PTR_EVALUATOR(const signed char*, signed char*);
229EAGER_PTR_EVALUATOR(signed char*, const signed char*);
230EAGER_PTR_EVALUATOR(signed char*, signed char*);
231
232// Data for the log message, not stored in LogMessage to avoid increasing the stack size.
233class LogMessageData;
234
235// A LogMessage is a temporarily scoped object used by LOG and the unlikely part of a CHECK. The
236// destructor will abort if the severity is FATAL.
237class LogMessage {
238 public:
239  LogMessage(const char* file, unsigned int line, LogSeverity severity, int error);
240
241  ~LogMessage();  // TODO: enable REQUIRES(!Locks::logging_lock_).
242
243  // Returns the stream associated with the message, the LogMessage performs output when it goes
244  // out of scope.
245  std::ostream& stream();
246
247  // The routine that performs the actual logging.
248  static void LogLine(const char* file, unsigned int line, LogSeverity severity, const char* msg);
249
250  // A variant of the above for use with little stack.
251  static void LogLineLowStack(const char* file, unsigned int line, LogSeverity severity,
252                              const char* msg);
253
254 private:
255  const std::unique_ptr<LogMessageData> data_;
256
257  DISALLOW_COPY_AND_ASSIGN(LogMessage);
258};
259
260// Allows to temporarily change the minimum severity level for logging.
261class ScopedLogSeverity {
262 public:
263  explicit ScopedLogSeverity(LogSeverity level);
264  ~ScopedLogSeverity();
265
266 private:
267  LogSeverity old_;
268};
269
270}  // namespace art
271
272#endif  // ART_RUNTIME_BASE_LOGGING_H_
273