Botan  2.8.0
Crypto and TLS for C++11
filter.h
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1 /*
2 * Filter
3 * (C) 1999-2007 Jack Lloyd
4 * (C) 2013 Joel Low
5 *
6 * Botan is released under the Simplified BSD License (see license.txt)
7 */
8 
9 #ifndef BOTAN_FILTER_H_
10 #define BOTAN_FILTER_H_
11 
12 #include <botan/secmem.h>
13 #include <vector>
14 #include <string>
15 
16 namespace Botan {
17 
18 /**
19 * This class represents general abstract filter objects.
20 */
22  {
23  public:
24  /**
25  * @return descriptive name for this filter
26  */
27  virtual std::string name() const = 0;
28 
29  /**
30  * Write a portion of a message to this filter.
31  * @param input the input as a byte array
32  * @param length the length of the byte array input
33  */
34  virtual void write(const uint8_t input[], size_t length) = 0;
35 
36  /**
37  * Start a new message. Must be closed by end_msg() before another
38  * message can be started.
39  */
40  virtual void start_msg() { /* default empty */ }
41 
42  /**
43  * Notify that the current message is finished; flush buffers and
44  * do end-of-message processing (if any).
45  */
46  virtual void end_msg() { /* default empty */ }
47 
48  /**
49  * Check whether this filter is an attachable filter.
50  * @return true if this filter is attachable, false otherwise
51  */
52  virtual bool attachable() { return true; }
53 
54  virtual ~Filter() = default;
55  protected:
56  /**
57  * @param in some input for the filter
58  * @param length the length of in
59  */
60  virtual void send(const uint8_t in[], size_t length);
61 
62  /**
63  * @param in some input for the filter
64  */
65  void send(uint8_t in) { send(&in, 1); }
66 
67  /**
68  * @param in some input for the filter
69  */
70  template<typename Alloc>
71  void send(const std::vector<uint8_t, Alloc>& in)
72  {
73  send(in.data(), in.size());
74  }
75 
76  /**
77  * @param in some input for the filter
78  * @param length the number of bytes of in to send
79  */
80  template<typename Alloc>
81  void send(const std::vector<uint8_t, Alloc>& in, size_t length)
82  {
83  BOTAN_ASSERT_NOMSG(length <= in.size());
84  send(in.data(), length);
85  }
86 
87  Filter();
88 
89  Filter(const Filter&) = delete;
90 
91  Filter& operator=(const Filter&) = delete;
92 
93  private:
94  /**
95  * Start a new message in *this and all following filters. Only for
96  * internal use, not intended for use in client applications.
97  */
98  void new_msg();
99 
100  /**
101  * End a new message in *this and all following filters. Only for
102  * internal use, not intended for use in client applications.
103  */
104  void finish_msg();
105 
106  friend class Pipe;
107  friend class Fanout_Filter;
108 
109  size_t total_ports() const;
110  size_t current_port() const { return m_port_num; }
111 
112  /**
113  * Set the active port
114  * @param new_port the new value
115  */
116  void set_port(size_t new_port);
117 
118  size_t owns() const { return m_filter_owns; }
119 
120  /**
121  * Attach another filter to this one
122  * @param f filter to attach
123  */
124  void attach(Filter* f);
125 
126  /**
127  * @param filters the filters to set
128  * @param count number of items in filters
129  */
130  void set_next(Filter* filters[], size_t count);
131  Filter* get_next() const;
132 
133  secure_vector<uint8_t> m_write_queue;
134  std::vector<Filter*> m_next; // not owned
135  size_t m_port_num, m_filter_owns;
136 
137  // true if filter belongs to a pipe --> prohibit filter sharing!
138  bool m_owned;
139  };
140 
141 /**
142 * This is the abstract Fanout_Filter base class.
143 **/
145  {
146  protected:
147  /**
148  * Increment the number of filters past us that we own
149  */
150  void incr_owns() { ++m_filter_owns; }
151 
152  void set_port(size_t n) { Filter::set_port(n); }
153 
154  void set_next(Filter* f[], size_t n) { Filter::set_next(f, n); }
155 
156  void attach(Filter* f) { Filter::attach(f); }
157 
158  private:
159  friend class Threaded_Fork;
160  using Filter::m_write_queue;
161  using Filter::total_ports;
162  using Filter::m_next;
163  };
164 
165 /**
166 * The type of checking to be performed by decoders:
167 * NONE - no checks, IGNORE_WS - perform checks, but ignore
168 * whitespaces, FULL_CHECK - perform checks, also complain
169 * about white spaces.
170 */
172 
173 }
174 
175 #endif
void set_port(size_t n)
Definition: filter.h:152
void attach(Filter *f)
Definition: filter.h:156
#define BOTAN_PUBLIC_API(maj, min)
Definition: compiler.h:27
void send(uint8_t in)
Definition: filter.h:65
void set_next(Filter *f[], size_t n)
Definition: filter.h:154
#define BOTAN_ASSERT_NOMSG(expr)
Definition: assert.h:68
void send(const std::vector< uint8_t, Alloc > &in)
Definition: filter.h:71
std::string name
void send(const std::vector< uint8_t, Alloc > &in, size_t length)
Definition: filter.h:81
virtual void start_msg()
Definition: filter.h:40
Definition: alg_id.cpp:13
virtual void end_msg()
Definition: filter.h:46
virtual bool attachable()
Definition: filter.h:52
Decoder_Checking
Definition: filter.h:171