mirror of
https://github.com/zeek/zeek.git
synced 2025-10-02 06:38:20 +00:00
126 lines
3.5 KiB
C++
126 lines
3.5 KiB
C++
// See the file "COPYING" in the main distribution directory for copyright.
|
|
|
|
#pragma once
|
|
|
|
namespace zeek::detail {
|
|
|
|
class Pipe {
|
|
public:
|
|
/**
|
|
* Create a pair of file descriptors via pipe(), or aborts if it cannot.
|
|
* @param flags0 file descriptor flags to set on read end of pipe.
|
|
* @param flags1 file descriptor flags to set on write end of pipe.
|
|
* @param status_flags0 descriptor status flags to set on read end of pipe.
|
|
* @param status_flags1 descriptor status flags to set on write end of pipe.
|
|
* @param fds may be supplied to open an existing file descriptors rather
|
|
* than create ones from a new pipe. Should point to memory containing
|
|
* two consecutive file descriptors, the "read" one and then the "write" one.
|
|
*/
|
|
explicit Pipe(int flags0 = 0, int flags1 = 0, int status_flags0 = 0, int status_flags1 = 0, int* fds = nullptr);
|
|
|
|
/**
|
|
* Close the pair of file descriptors owned by the object.
|
|
*/
|
|
~Pipe();
|
|
|
|
/**
|
|
* Make a copy of another Pipe object (file descriptors are dup'd).
|
|
*/
|
|
Pipe(const Pipe& other);
|
|
|
|
/**
|
|
* Assign a Pipe object by closing file descriptors and duping those of
|
|
* the other.
|
|
*/
|
|
Pipe& operator=(const Pipe& other);
|
|
|
|
/**
|
|
* @return the file descriptor associated with the read-end of the pipe.
|
|
*/
|
|
int ReadFD() const { return fds[0]; }
|
|
|
|
/**
|
|
* @return the file descriptor associated with the write-end of the pipe.
|
|
*/
|
|
int WriteFD() const { return fds[1]; }
|
|
|
|
/**
|
|
* Sets the given file descriptor flags for both the read and write end
|
|
* of the pipe.
|
|
*/
|
|
void SetFlags(int flags);
|
|
|
|
/**
|
|
* Unsets the given file descriptor flags for both the read and write end
|
|
* of the pipe.
|
|
*/
|
|
void UnsetFlags(int flags);
|
|
|
|
private:
|
|
int fds[2];
|
|
int flags[2];
|
|
int status_flags[2];
|
|
};
|
|
|
|
/**
|
|
* A pair of pipes that can be used for bi-directional IPC.
|
|
*/
|
|
class PipePair {
|
|
public:
|
|
/**
|
|
* Create a pair of pipes
|
|
* @param flags file descriptor flags to set on pipes
|
|
* @status_flags descriptor status flags to set on pipes
|
|
* @fds may be supplied to open existing file descriptors rather
|
|
* than create ones from a new pair of pipes. Should point to memory
|
|
* containing four consecutive file descriptors, "read" end and "write" end
|
|
* of the first pipe followed by the "read" end and "write" end of the
|
|
* second pipe.
|
|
*/
|
|
PipePair(int flags, int status_flags, int* fds = nullptr);
|
|
|
|
/**
|
|
* @return the pipe used for receiving input
|
|
*/
|
|
Pipe& In() { return pipes[swapped]; }
|
|
|
|
/**
|
|
* @return the pipe used for sending output
|
|
*/
|
|
Pipe& Out() { return pipes[! swapped]; }
|
|
|
|
/**
|
|
* @return the pipe used for receiving input
|
|
*/
|
|
const Pipe& In() const { return pipes[swapped]; }
|
|
|
|
/**
|
|
* @return the pipe used for sending output
|
|
*/
|
|
const Pipe& Out() const { return pipes[! swapped]; }
|
|
|
|
/**
|
|
* @return a file descriptor that may used for receiving messages by
|
|
* polling/reading it.
|
|
*/
|
|
int InFD() const { return In().ReadFD(); }
|
|
|
|
/**
|
|
* @return a file descriptor that may be used for sending messages by
|
|
* writing to it.
|
|
*/
|
|
int OutFD() const { return Out().WriteFD(); }
|
|
|
|
/**
|
|
* Swaps the meaning of the pipes in the pair. E.g. call this after
|
|
* fork()'ing so that the child process uses the right pipe for
|
|
* reading/writing.
|
|
*/
|
|
void Swap() { swapped = ! swapped; }
|
|
|
|
private:
|
|
Pipe pipes[2];
|
|
bool swapped = false;
|
|
};
|
|
|
|
} // namespace zeek::detail
|