HepMC3 event record library
WriterAscii.h
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1 // -*- C++ -*-
2 //
3 // This file is part of HepMC
4 // Copyright (C) 2014-2019 The HepMC collaboration (see AUTHORS for details)
5 //
6 #ifndef HEPMC3_WRITERASCII_H
7 #define HEPMC3_WRITERASCII_H
8 ///
9 /// @file WriterAscii.h
10 /// @brief Definition of class \b WriterAscii
11 ///
12 /// @class HepMC3::WriterAscii
13 /// @brief GenEvent I/O serialization for structured text files
14 ///
15 /// @ingroup IO
16 ///
17 #include "HepMC3/Writer.h"
18 #include "HepMC3/GenEvent.h"
19 #include "HepMC3/GenRunInfo.h"
20 #include <string>
21 #include <fstream>
22 
23 namespace HepMC3 {
24 
25 class WriterAscii : public Writer {
26 public:
27 
28  /// @brief Constructor
29  /// @warning If file already exists, it will be cleared before writing
30  WriterAscii(const std::string& filename,
31  shared_ptr<GenRunInfo> run = shared_ptr<GenRunInfo>());
32 
33 #ifndef HEPMC3_PYTHON_BINDINGS
34  /// @brief Constructor from ostream
35  WriterAscii(std::ostream& stream,
36  shared_ptr<GenRunInfo> run = shared_ptr<GenRunInfo>());
37 #endif
38 
39  /// @brief Destructor
40  ~WriterAscii();
41 
42  /// @brief Write event to file
43  ///
44  /// @param[in] evt Event to be serialized
45  void write_event(const GenEvent& evt) override;
46 
47  /// @brief Write the GenRunInfo object to file.
48  void write_run_info();
49 
50  /// @brief Return status of the stream
51  bool failed() override;
52 
53  /// @brief Close file stream
54  void close() override;
55 
56  /// @brief Set output precision
57  ///
58  /// So far available range is [2,24]. Default is 16.
59  void set_precision(const int& prec );
60  /// @brief Return output precision
61  int precision() const;
62 private:
63 
64  /// @name Buffer management
65  //@{
66 
67  /// @brief Attempts to allocate buffer of the chosen size
68  ///
69  /// This function can be called manually by the user or will be called
70  /// before first read/write operation
71  ///
72  /// @note If buffer size is too large it will be divided by 2 until it is
73  /// small enough for system to allocate
74  void allocate_buffer();
75 
76  /// @brief Set buffer size (in bytes)
77  ///
78  /// Default is 256kb. Minimum is 256b.
79  /// Size can only be changed before first read/write operation.
80  void set_buffer_size(const size_t& size );
81 
82  /// @brief Escape '\' and '\n' characters in string
83  std::string escape(const std::string& s) const;
84 
85  /// Inline function flushing buffer to output stream when close to buffer capacity
86  void flush();
87 
88  /// Inline function forcing flush to the output stream
89  void forced_flush();
90 
91  //@}
92 
93 
94  /// @name Write helpers
95  //@{
96 
97  /// @brief Inline function for writing strings
98  ///
99  /// Since strings can be long (maybe even longer than buffer) they have to be dealt
100  /// with separately.
101  void write_string( const std::string &str );
102 
103  /// @brief Write vertex
104  ///
105  /// Helper routine for writing single vertex to file
106  void write_vertex(ConstGenVertexPtr v);
107 
108  /// @brief Write particle
109  ///
110  /// Helper routine for writing single particle to file
111  void write_particle(ConstGenParticlePtr p, int second_field);
112 
113  //@}
114 
115 private:
116 
117  std::ofstream m_file; //!< Output file
118  std::ostream* m_stream; //!< Output stream
119 
120  int m_precision; //!< Output precision
121  char* m_buffer; //!< Stream buffer
122  char* m_cursor; //!< Cursor inside stream buffer
123  unsigned long m_buffer_size; //!< Buffer size
124 
125 };
126 
127 
128 } // namespace HepMC3
129 
130 #endif
Definition of class GenRunInfo.
void write_string(const std::string &str)
Inline function for writing strings.
Definition: WriterAscii.cc:335
void forced_flush()
Inline function forcing flush to the output stream.
Definition: WriterAscii.cc:260
int m_precision
Output precision.
Definition: WriterAscii.h:120
std::ostream * m_stream
Output stream.
Definition: WriterAscii.h:118
void set_buffer_size(const size_t &size)
Set buffer size (in bytes)
Definition: WriterAscii.cc:372
char * m_cursor
Cursor inside stream buffer.
Definition: WriterAscii.h:122
void allocate_buffer()
Attempts to allocate buffer of the chosen size.
Definition: WriterAscii.cc:170
WriterAscii(const std::string &filename, shared_ptr< GenRunInfo > run=shared_ptr< GenRunInfo >())
Constructor.
Definition: WriterAscii.cc:22
void write_particle(ConstGenParticlePtr p, int second_field)
Write particle.
Definition: WriterAscii.cc:311
unsigned long m_buffer_size
Buffer size.
Definition: WriterAscii.h:123
void set_precision(const int &prec)
Set output precision.
Definition: WriterAscii.cc:363
bool failed() override
Return status of the stream.
Definition: WriterAscii.cc:361
Stores event-related information.
Definition: GenEvent.h:41
char * m_buffer
Stream buffer.
Definition: WriterAscii.h:121
void write_vertex(ConstGenVertexPtr v)
Write vertex.
Definition: WriterAscii.cc:208
Definition of interface Writer.
int precision() const
Return output precision.
Definition: WriterAscii.cc:368
std::string escape(const std::string &s) const
Escape &#39;\&#39; and &#39; &#39; characters in string.
Definition: WriterAscii.cc:190
~WriterAscii()
Destructor.
Definition: WriterAscii.cc:57
void write_run_info()
Write the GenRunInfo object to file.
Definition: WriterAscii.cc:267
void write_event(const GenEvent &evt) override
Write event to file.
Definition: WriterAscii.cc:63
Base class for all I/O writers.
Definition: Writer.h:25
std::ofstream m_file
Output file.
Definition: WriterAscii.h:117
Definition of class GenEvent.
void close() override
Close file stream.
Definition: WriterAscii.cc:354
void flush()
Inline function flushing buffer to output stream when close to buffer capacity.
Definition: WriterAscii.cc:247
GenEvent I/O serialization for structured text files.
Definition: WriterAscii.h:25