1 //===- CLog.h - Logging Interface -------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_CLANG_TOOLS_LIBCLANG_CLOG_H 10 #define LLVM_CLANG_TOOLS_LIBCLANG_CLOG_H 11 12 #include "clang-c/Index.h" 13 #include "clang/Basic/FileEntry.h" 14 #include "clang/Basic/LLVM.h" 15 #include "llvm/ADT/IntrusiveRefCntPtr.h" 16 #include "llvm/ADT/SmallString.h" 17 #include "llvm/ADT/StringRef.h" 18 #include "llvm/Support/Compiler.h" 19 #include "llvm/Support/raw_ostream.h" 20 #include <string> 21 22 namespace llvm { 23 class format_object_base; 24 } 25 26 namespace clang { 27 namespace cxindex { 28 29 class Logger; 30 typedef IntrusiveRefCntPtr<Logger> LogRef; 31 32 /// Collects logging output and writes it to stderr when it's destructed. 33 /// Common use case: 34 /// \code 35 /// if (LogRef Log = Logger::make(__func__)) { 36 /// *Log << "stuff"; 37 /// } 38 /// \endcode 39 class Logger : public RefCountedBase<Logger> { 40 std::string Name; 41 bool Trace; 42 SmallString<64> Msg; 43 llvm::raw_svector_ostream LogOS; 44 public: getEnvVar()45 static const char *getEnvVar() { 46 static const char *sCachedVar = ::getenv("LIBCLANG_LOGGING"); 47 return sCachedVar; 48 } isLoggingEnabled()49 static bool isLoggingEnabled() { return getEnvVar() != nullptr; } isStackTracingEnabled()50 static bool isStackTracingEnabled() { 51 if (const char *EnvOpt = Logger::getEnvVar()) 52 return llvm::StringRef(EnvOpt) == "2"; 53 return false; 54 } 55 static LogRef make(llvm::StringRef name, 56 bool trace = isStackTracingEnabled()) { 57 if (isLoggingEnabled()) 58 return new Logger(name, trace); 59 return nullptr; 60 } 61 Logger(llvm::StringRef name,bool trace)62 explicit Logger(llvm::StringRef name, bool trace) 63 : Name(std::string(name)), Trace(trace), LogOS(Msg) {} 64 ~Logger(); 65 66 Logger &operator<<(CXTranslationUnit); 67 Logger &operator<<(FileEntryRef FE); 68 Logger &operator<<(CXCursor cursor); 69 Logger &operator<<(CXSourceLocation); 70 Logger &operator<<(CXSourceRange); 71 Logger &operator<<(CXString); 72 Logger &operator<<(llvm::StringRef Str) { LogOS << Str; return *this; } 73 Logger &operator<<(const char *Str) { 74 if (Str) 75 LogOS << Str; 76 return *this; 77 } 78 Logger &operator<<(unsigned long N) { LogOS << N; return *this; } 79 Logger &operator<<(long N) { LogOS << N ; return *this; } 80 Logger &operator<<(unsigned int N) { LogOS << N; return *this; } 81 Logger &operator<<(int N) { LogOS << N; return *this; } 82 Logger &operator<<(char C) { LogOS << C; return *this; } 83 Logger &operator<<(unsigned char C) { LogOS << C; return *this; } 84 Logger &operator<<(signed char C) { LogOS << C; return *this; } 85 Logger &operator<<(const llvm::format_object_base &Fmt); 86 }; 87 88 } 89 } 90 91 /// Macros to automate common uses of Logger. Like this: 92 /// \code 93 /// LOG_FUNC_SECTION { 94 /// *Log << "blah"; 95 /// } 96 /// \endcode 97 #define LOG_SECTION(NAME) \ 98 if (clang::cxindex::LogRef Log = clang::cxindex::Logger::make(NAME)) 99 #define LOG_FUNC_SECTION LOG_SECTION(__func__) 100 101 #endif 102