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24 #ifndef SHARE_LOGGING_LOGOUTPUT_HPP
25 #define SHARE_LOGGING_LOGOUTPUT_HPP
26 
27 #include "logging/logDecorators.hpp"
28 #include "logging/logLevel.hpp"
29 #include "logging/logMessageBuffer.hpp"
30 #include "memory/allocation.hpp"
31 #include "utilities/globalDefinitions.hpp"
32 
33 class LogDecorations;
34 class LogMessageBuffer;
35 class LogSelection;
36 class LogTagSet;
37 
38 // The base class/interface for log outputs.
39 // Keeps track of the latest configuration string,
40 // and its selected decorators.
41 class LogOutput : public CHeapObj<mtLogging> {
42   // Make LogConfiguration a friend to allow it to modify the configuration string.
43   friend class LogConfiguration;
44 
45  private:
46   static const size_t InitialConfigBufferSize = 256;
47 
48   // Track if the output has been reconfigured dynamically during runtime.
49   // The status is set each time the configuration of the output is modified,
50   // and is reset once after logging initialization is complete.
51   bool _reconfigured;
52 
53   char* _config_string;
54   size_t _config_string_buffer_size;
55 
56   // Adds the log selection to the config description (e.g. "tag1+tag2*=level").
57   void add_to_config_string(const LogSelection& selection);
58 
59  protected:
60   LogDecorators _decorators;
61 
62   // Replaces the current config description with the given string.
63   void set_config_string(const char* string);
64 
65   // Update the config string for this output to reflect its current configuration
66   void update_config_string(const size_t on_level[LogLevel::Count]);
67 
68  public:
set_decorators(const LogDecorators & decorators)69   void set_decorators(const LogDecorators &decorators) {
70     _decorators = decorators;
71   }
72 
decorators() const73   const LogDecorators& decorators() const {
74     return _decorators;
75   }
76 
is_reconfigured() const77   bool is_reconfigured() const {
78     return _reconfigured;
79   }
80 
config_string() const81   const char* config_string() const {
82     return _config_string;
83   }
84 
LogOutput()85   LogOutput() : _reconfigured(false), _config_string(NULL), _config_string_buffer_size(0) {
86   }
87 
88   virtual ~LogOutput();
89 
90   // If the output can be rotated, trigger a forced rotation, otherwise do nothing.
91   // Log outputs with rotation capabilities should override this.
force_rotate()92   virtual void force_rotate() {
93     // Do nothing by default.
94   }
95 
96   virtual void describe(outputStream *out);
97 
98   virtual const char* name() const = 0;
99   virtual bool initialize(const char* options, outputStream* errstream) = 0;
100   virtual int write(const LogDecorations& decorations, const char* msg) = 0;
101   virtual int write(LogMessageBuffer::Iterator msg_iterator) = 0;
102 };
103 
104 #endif // SHARE_LOGGING_LOGOUTPUT_HPP
105