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  NONE,            // Fake level, don't log at all.
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 collector;
42  bool compiler;
43  bool deopt;
44  bool gc;
45  bool heap;
46  bool jdwp;
47  bool jit;
48  bool jni;
49  bool monitor;
50  bool oat;
51  bool profiler;
52  bool signals;
53  bool simulator;
54  bool startup;
55  bool third_party_jni;  // Enabled with "-verbose:third-party-jni".
56  bool threads;
57  bool verifier;
58  bool image;
59  bool systrace_lock_logging;  // Enabled with "-verbose:sys-locks".
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// CHECK that can be used in a constexpr function. For example,
164//    constexpr int half(int n) {
165//      return
166//          DCHECK_CONSTEXPR(n >= 0, , 0)
167//          CHECK_CONSTEXPR((n & 1) == 0), << "Extra debugging output: n = " << n, 0)
168//          n / 2;
169//    }
170#define CHECK_CONSTEXPR(x, out, dummy) \
171  (UNLIKELY(!(x))) ? (LOG(::art::FATAL) << "Check failed: " << #x out, dummy) :
172
173
174// DCHECKs are debug variants of CHECKs only enabled in debug builds. Generally CHECK should be
175// used unless profiling identifies a CHECK as being in performance critical code.
176#if defined(NDEBUG)
177static constexpr bool kEnableDChecks = false;
178#else
179static constexpr bool kEnableDChecks = true;
180#endif
181
182#define DCHECK(x) if (::art::kEnableDChecks) CHECK(x)
183#define DCHECK_EQ(x, y) if (::art::kEnableDChecks) CHECK_EQ(x, y)
184#define DCHECK_NE(x, y) if (::art::kEnableDChecks) CHECK_NE(x, y)
185#define DCHECK_LE(x, y) if (::art::kEnableDChecks) CHECK_LE(x, y)
186#define DCHECK_LT(x, y) if (::art::kEnableDChecks) CHECK_LT(x, y)
187#define DCHECK_GE(x, y) if (::art::kEnableDChecks) CHECK_GE(x, y)
188#define DCHECK_GT(x, y) if (::art::kEnableDChecks) CHECK_GT(x, y)
189#define DCHECK_STREQ(s1, s2) if (::art::kEnableDChecks) CHECK_STREQ(s1, s2)
190#define DCHECK_STRNE(s1, s2) if (::art::kEnableDChecks) CHECK_STRNE(s1, s2)
191#if defined(NDEBUG)
192#define DCHECK_CONSTEXPR(x, out, dummy)
193#else
194#define DCHECK_CONSTEXPR(x, out, dummy) CHECK_CONSTEXPR(x, out, dummy)
195#endif
196
197// Temporary class created to evaluate the LHS and RHS, used with MakeEagerEvaluator to infer the
198// types of LHS and RHS.
199template <typename LHS, typename RHS>
200struct EagerEvaluator {
201  EagerEvaluator(LHS l, RHS r) : lhs(l), rhs(r) { }
202  LHS lhs;
203  RHS rhs;
204};
205
206// Helper function for CHECK_xx.
207template <typename LHS, typename RHS>
208static inline EagerEvaluator<LHS, RHS> MakeEagerEvaluator(LHS lhs, RHS rhs) {
209  return EagerEvaluator<LHS, RHS>(lhs, rhs);
210}
211
212// Explicitly instantiate EagerEvalue for pointers so that char*s aren't treated as strings. To
213// compare strings use CHECK_STREQ and CHECK_STRNE. We rely on signed/unsigned warnings to
214// protect you against combinations not explicitly listed below.
215#define EAGER_PTR_EVALUATOR(T1, T2) \
216  template <> struct EagerEvaluator<T1, T2> { \
217    EagerEvaluator(T1 l, T2 r) \
218        : lhs(reinterpret_cast<const void*>(l)), \
219          rhs(reinterpret_cast<const void*>(r)) { } \
220    const void* lhs; \
221    const void* rhs; \
222  }
223EAGER_PTR_EVALUATOR(const char*, const char*);
224EAGER_PTR_EVALUATOR(const char*, char*);
225EAGER_PTR_EVALUATOR(char*, const char*);
226EAGER_PTR_EVALUATOR(char*, char*);
227EAGER_PTR_EVALUATOR(const unsigned char*, const unsigned char*);
228EAGER_PTR_EVALUATOR(const unsigned char*, unsigned char*);
229EAGER_PTR_EVALUATOR(unsigned char*, const unsigned char*);
230EAGER_PTR_EVALUATOR(unsigned char*, unsigned char*);
231EAGER_PTR_EVALUATOR(const signed char*, const signed char*);
232EAGER_PTR_EVALUATOR(const signed char*, signed char*);
233EAGER_PTR_EVALUATOR(signed char*, const signed char*);
234EAGER_PTR_EVALUATOR(signed char*, signed char*);
235
236// Data for the log message, not stored in LogMessage to avoid increasing the stack size.
237class LogMessageData;
238
239// A LogMessage is a temporarily scoped object used by LOG and the unlikely part of a CHECK. The
240// destructor will abort if the severity is FATAL.
241class LogMessage {
242 public:
243  LogMessage(const char* file, unsigned int line, LogSeverity severity, int error);
244
245  ~LogMessage();  // TODO: enable REQUIRES(!Locks::logging_lock_).
246
247  // Returns the stream associated with the message, the LogMessage performs output when it goes
248  // out of scope.
249  std::ostream& stream();
250
251  // The routine that performs the actual logging.
252  static void LogLine(const char* file, unsigned int line, LogSeverity severity, const char* msg);
253
254  // A variant of the above for use with little stack.
255  static void LogLineLowStack(const char* file, unsigned int line, LogSeverity severity,
256                              const char* msg);
257
258 private:
259  const std::unique_ptr<LogMessageData> data_;
260
261  DISALLOW_COPY_AND_ASSIGN(LogMessage);
262};
263
264// Allows to temporarily change the minimum severity level for logging.
265class ScopedLogSeverity {
266 public:
267  explicit ScopedLogSeverity(LogSeverity level);
268  ~ScopedLogSeverity();
269
270 private:
271  LogSeverity old_;
272};
273
274}  // namespace art
275
276#endif  // ART_RUNTIME_BASE_LOGGING_H_
277