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//===--------------------- TimeSpecTimeout.h --------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef utility_TimeSpecTimeout_h_
#define utility_TimeSpecTimeout_h_

#include "lldb/Host/TimeValue.h"

namespace lldb_private {

class TimeSpecTimeout
{
public:
    TimeSpecTimeout() :
        m_infinite (false)
    {
        m_timespec.tv_sec = 0;
        m_timespec.tv_nsec = 0;
    }
    ~TimeSpecTimeout()
    {
    }

    //----------------------------------------------------------------------
    /// Sets the timespec pointer correctly given a timeout relative to the
    /// current time. This function should be called immediately prior to
    /// calling the function you will use this timeout with since time can
    /// elapse between when this function is called and when the timeout is
    /// used.
    ///
    /// @param[in] timeout_usec
    ///     The timeout in micro seconds. If timeout_usec is UINT32_MAX, the
    ///     timeout should be set to INFINITE. Otherwise the current time is
    ///     filled into the timespec and \a timeout_usec is added to the
    ///     current time.
    ///
    /// @return
    ///     If the timeout is INFINITE, then return NULL, otherwise return
    ///     a pointer to the timespec with the appropriate timeout value.
    //----------------------------------------------------------------------
    const struct timespec *
    SetAbsoluteTimeoutMircoSeconds32 (uint32_t timeout_usec);

    //----------------------------------------------------------------------
    /// Sets the timespec pointer correctly given a relative time in micro
    /// seconds. 
    ///
    /// @param[in] timeout_usec
    ///     The timeout in micro seconds. If timeout_usec is UINT32_MAX, the
    ///     timeout should be set to INFINITE. Otherwise \a timeout_usec
    ///     is correctly placed into the timespec.
    ///
    /// @return
    ///     If the timeout is INFINITE, then return NULL, otherwise return
    ///     a pointer to the timespec with the appropriate timeout value.
    //----------------------------------------------------------------------
    const struct timespec *
    SetRelativeTimeoutMircoSeconds32 (uint32_t timeout_usec);

    //----------------------------------------------------------------------
    /// Gets the timespec pointer that is appropriate for the timeout
    /// specified. This function should only be used after a call to
    /// SetRelativeTimeoutXXX() functions.
    ///
    /// @return
    ///     If the timeout is INFINITE, then return NULL, otherwise return
    ///     a pointer to the timespec with the appropriate timeout value.
    //----------------------------------------------------------------------
    const struct timespec *
    GetTimeSpecPtr () const
    {
        if (m_infinite)
            return NULL;
        return &m_timespec;
    }
    
protected:
    struct timespec m_timespec;
    bool m_infinite;
};

} // namespace lldb_private

#endif // #ifndef utility_TimeSpecTimeout_h_