pcap-helper.hpp
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8  * Beijing Institute of Technology,
9  * The University of Memphis.
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25 
26 #ifndef NFD_DAEMON_FACE_PCAP_HELPER_HPP
27 #define NFD_DAEMON_FACE_PCAP_HELPER_HPP
28 
29 #include "core/common.hpp"
30 
31 #ifndef NFD_HAVE_LIBPCAP
32 #error "Cannot include this file when libpcap is not available"
33 #endif
34 
35 // forward declarations
36 struct pcap;
37 typedef pcap pcap_t;
38 
39 namespace nfd::face {
40 
44 class PcapHelper : noncopyable
45 {
46 public:
47  class Error : public std::runtime_error
48  {
49  public:
50  using std::runtime_error::runtime_error;
51  };
52 
58  explicit
59  PcapHelper(const std::string& interfaceName);
60 
61  ~PcapHelper() noexcept;
62 
69  void
70  activate(int dlt);
71 
76  void
77  close() noexcept;
78 
86  int
87  getFd() const;
88 
95  std::string
96  getLastError() const noexcept;
97 
103  size_t
104  getNDropped() const;
105 
113  void
114  setPacketFilter(const char* filter) const;
115 
125  std::tuple<span<const uint8_t>, std::string>
126  readNextPacket() const noexcept;
127 
128  operator pcap_t*() const noexcept
129  {
130  return m_pcap;
131  }
132 
133 private:
134  pcap_t* m_pcap = nullptr;
135 };
136 
137 } // namespace nfd::face
138 
139 #endif // NFD_DAEMON_FACE_PCAP_HELPER_HPP
Helper class for dealing with libpcap handles.
Definition: pcap-helper.hpp:45
PcapHelper(const std::string &interfaceName)
Create a libpcap context for live packet capture on a network interface.
Definition: pcap-helper.cpp:40
int getFd() const
Obtain a file descriptor that can be used in calls such as select(2) and poll(2).
Definition: pcap-helper.cpp:93
std::string getLastError() const noexcept
Get last error message.
void activate(int dlt)
Start capturing packets.
Definition: pcap-helper.cpp:64
size_t getNDropped() const
Get the number of packets dropped by the kernel, as reported by libpcap.
void setPacketFilter(const char *filter) const
Install a BPF filter on the receiving socket.
std::tuple< span< const uint8_t >, std::string > readNextPacket() const noexcept
Read the next packet captured on the interface.
void close() noexcept
Stop capturing and close the handle.
Definition: pcap-helper.cpp:84
pcap pcap_t
Definition: pcap-helper.hpp:36