diff options
Diffstat (limited to 'lldb/source/Utility/PseudoTerminal.h')
| -rw-r--r-- | lldb/source/Utility/PseudoTerminal.h | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/lldb/source/Utility/PseudoTerminal.h b/lldb/source/Utility/PseudoTerminal.h new file mode 100644 index 00000000000..5d680745a32 --- /dev/null +++ b/lldb/source/Utility/PseudoTerminal.h @@ -0,0 +1,267 @@ +//===-- PseudoTerminal.h ----------------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef liblldb_PseudoTerminal_h_ +#define liblldb_PseudoTerminal_h_ +#if defined(__cplusplus) + + +#include <fcntl.h> +#include <termios.h> +#include <string> + +#include "lldb/lldb-defines.h" + +namespace lldb_utility { + +//---------------------------------------------------------------------- +/// @class PseudoTerminal PseudoTerminal.h "lldb/Core/PseudoTerminal.h" +/// @brief A pseudo terminal helper class. +/// +/// The pseudo terminal class abtracts the use of pseudo terminals on +/// the host system. +//---------------------------------------------------------------------- +class PseudoTerminal +{ +public: + enum + { + invalid_fd = -1, ///< Invalid file descriptor value + }; + + //------------------------------------------------------------------ + /// Default constructor + /// + /// Constructs this object with invalid master and slave file + /// descriptors. + //------------------------------------------------------------------ + PseudoTerminal (); + + //------------------------------------------------------------------ + /// Destructor + /// + /// The destructor will close the master and slave file descriptors + /// if they are valid and ownwership has not been released using + /// one of: + /// @li PseudoTerminal::ReleaseMasterFileDescriptor() + /// @li PseudoTerminal::ReleaseSaveFileDescriptor() + //------------------------------------------------------------------ + ~PseudoTerminal (); + + //------------------------------------------------------------------ + /// Close the master file descriptor if it is valid. + //------------------------------------------------------------------ + void + CloseMasterFileDescriptor (); + + //------------------------------------------------------------------ + /// Close the slave file descriptor if it is valid. + //------------------------------------------------------------------ + void + CloseSlaveFileDescriptor (); + + //------------------------------------------------------------------ + /// Fork a child process that uses pseudo terminals for its stdio. + /// + /// In the parent process, a call to this function results in a pid + /// being returned. If the pid is valid, the master file descriptor + /// can be used for read/write access to stdio of the child process. + /// + /// In the child process the stdin/stdout/stderr will already be + /// routed to the slave pseudo terminal and the master file + /// descriptor will be closed as it is no longer needed by the child + /// process. + /// + /// This class will close the file descriptors for the master/slave + /// when the destructor is called. The file handles can be released + /// using either: + /// @li PseudoTerminal::ReleaseMasterFileDescriptor() + /// @li PseudoTerminal::ReleaseSaveFileDescriptor() + /// + /// @param[out] error + /// An pointer to an error that can describe any errors that + /// occur. This can be NULL if no error status is desired. + /// + /// @return + /// @li \b Parent process: a child process ID that is greater + /// than zero, or -1 if the fork fails. + /// @li \b Child process: zero. + //------------------------------------------------------------------ + pid_t + Fork (char *error_str, size_t error_len); + + //------------------------------------------------------------------ + /// The master file descriptor accessor. + /// + /// This object retains ownership of the master file descriptor when + /// this accessor is used. Users can call the member function + /// PseudoTerminal::ReleaseMasterFileDescriptor() if this + /// object should release ownership of the slave file descriptor. + /// + /// @return + /// The master file descriptor, or PseudoTerminal::invalid_fd + /// if the master file descriptor is not currently valid. + /// + /// @see PseudoTerminal::ReleaseMasterFileDescriptor() + //------------------------------------------------------------------ + int + GetMasterFileDescriptor () const; + + //------------------------------------------------------------------ + /// The slave file descriptor accessor. + /// + /// This object retains ownership of the slave file descriptor when + /// this accessor is used. Users can call the member function + /// PseudoTerminal::ReleaseSlaveFileDescriptor() if this + /// object should release ownership of the slave file descriptor. + /// + /// @return + /// The slave file descriptor, or PseudoTerminal::invalid_fd + /// if the slave file descriptor is not currently valid. + /// + /// @see PseudoTerminal::ReleaseSlaveFileDescriptor() + //------------------------------------------------------------------ + int + GetSlaveFileDescriptor () const; + + //------------------------------------------------------------------ + /// Get the name of the slave pseudo terminal. + /// + /// A master pseudo terminal should already be valid prior to + /// calling this function. + /// + /// @param[out] error + /// An pointer to an error that can describe any errors that + /// occur. This can be NULL if no error status is desired. + /// + /// @return + /// The name of the slave pseudo terminal as a NULL terminated + /// C. This string that comes from static memory, so a copy of + /// the string should be made as subsequent calls can change + /// this value. NULL is returned if this object doesn't have + /// a valid master pseudo terminal opened or if the call to + /// \c ptsname() fails. + /// + /// @see PseudoTerminal::OpenFirstAvailableMaster() + //------------------------------------------------------------------ + const char* + GetSlaveName (char *error_str, size_t error_len) const; + + //------------------------------------------------------------------ + /// Open the first available pseudo terminal. + /// + /// Opens the first available pseudo terminal with \a oflag as the + /// permissions. The opened master file descriptor is stored in this + /// object and can be accessed by calling the + /// PseudoTerminal::GetMasterFileDescriptor() accessor. Clients + /// can call the PseudoTerminal::ReleaseMasterFileDescriptor() + /// accessor function if they wish to use the master file descriptor + /// beyond the lifespan of this object. + /// + /// If this object still has a valid master file descriptor when its + /// destructor is called, it will close it. + /// + /// @param[in] oflag + /// Flags to use when calling \c posix_openpt(\a oflag). + /// A value of "O_RDWR|O_NOCTTY" is suggested. + /// + /// @param[out] error + /// An pointer to an error that can describe any errors that + /// occur. This can be NULL if no error status is desired. + /// + /// @return + /// @li \b true when the a master files descriptor is + /// successfully opened. + /// @li \b false if anything goes wrong. + /// + /// @see PseudoTerminal::GetMasterFileDescriptor() + /// @see PseudoTerminal::ReleaseMasterFileDescriptor() + //------------------------------------------------------------------ + bool + OpenFirstAvailableMaster (int oflag, char *error_str, size_t error_len); + + //------------------------------------------------------------------ + /// Open the slave for the current master pseudo terminal. + /// + /// A master pseudo terminal should already be valid prior to + /// calling this function. The opened slave file descriptor is + /// stored in this object and can be accessed by calling the + /// PseudoTerminal::GetSlaveFileDescriptor() accessor. Clients + /// can call the PseudoTerminal::ReleaseSlaveFileDescriptor() + /// accessor function if they wish to use the slave file descriptor + /// beyond the lifespan of this object. + /// + /// If this object still has a valid slave file descriptor when its + /// destructor is called, it will close it. + /// + /// @param[in] oflag + /// Flags to use when calling \c open(\a oflag). + /// + /// @param[out] error + /// An pointer to an error that can describe any errors that + /// occur. This can be NULL if no error status is desired. + /// + /// @return + /// @li \b true when the a master files descriptor is + /// successfully opened. + /// @li \b false if anything goes wrong. + /// + /// @see PseudoTerminal::OpenFirstAvailableMaster() + /// @see PseudoTerminal::GetSlaveFileDescriptor() + /// @see PseudoTerminal::ReleaseSlaveFileDescriptor() + //------------------------------------------------------------------ + bool + OpenSlave (int oflag, char *error_str, size_t error_len); + + //------------------------------------------------------------------ + /// Release the master file descriptor. + /// + /// Releases ownership of the master pseudo terminal file descriptor + /// without closing it. The destructor for this class will close the + /// master file descriptor if the ownership isn't released using this + /// call and the master file descriptor has been opened. + /// + /// @return + /// The master file descriptor, or PseudoTerminal::invalid_fd + /// if the mast file descriptor is not currently valid. + //------------------------------------------------------------------ + int + ReleaseMasterFileDescriptor (); + + //------------------------------------------------------------------ + /// Release the slave file descriptor. + /// + /// Release ownership of the slave pseudo terminal file descriptor + /// without closing it. The destructor for this class will close the + /// slave file descriptor if the ownership isn't released using this + /// call and the slave file descriptor has been opened. + /// + /// @return + /// The slave file descriptor, or PseudoTerminal::invalid_fd + /// if the slave file descriptor is not currently valid. + //------------------------------------------------------------------ + int + ReleaseSlaveFileDescriptor (); + +protected: + //------------------------------------------------------------------ + // Member variables + //------------------------------------------------------------------ + int m_master_fd; ///< The file descriptor for the master. + int m_slave_fd; ///< The file descriptor for the slave. + +private: + DISALLOW_COPY_AND_ASSIGN (PseudoTerminal); + +}; + +} // namespace lldb + +#endif // #if defined(__cplusplus) +#endif // #ifndef liblldb_PseudoTerminal_h_ |
