/usr/include/Poco/Semaphore.h is in libpoco-dev 1.8.0.1-1ubuntu4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 | //
// Semaphore.h
//
// Library: Foundation
// Package: Threading
// Module: Semaphore
//
// Definition of the Semaphore class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_Semaphore_INCLUDED
#define Foundation_Semaphore_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/Exception.h"
#if defined(POCO_OS_FAMILY_WINDOWS)
#include "Poco/Semaphore_WIN32.h"
#elif defined(POCO_VXWORKS)
#include "Poco/Semaphore_VX.h"
#else
#include "Poco/Semaphore_POSIX.h"
#endif
namespace Poco {
class Foundation_API Semaphore: private SemaphoreImpl
/// A Semaphore is a synchronization object with the following
/// characteristics:
/// A semaphore has a value that is constrained to be a non-negative
/// integer and two atomic operations. The allowable operations are V
/// (here called set()) and P (here called wait()). A V (set()) operation
/// increases the value of the semaphore by one.
/// A P (wait()) operation decreases the value of the semaphore by one,
/// provided that can be done without violating the constraint that the
/// value be non-negative. A P (wait()) operation that is initiated when
/// the value of the semaphore is 0 suspends the calling thread.
/// The calling thread may continue when the value becomes positive again.
{
public:
Semaphore(int n);
Semaphore(int n, int max);
/// Creates the semaphore. The current value
/// of the semaphore is given in n. The
/// maximum value of the semaphore is given
/// in max.
/// If only n is given, it must be greater than
/// zero.
/// If both n and max are given, max must be
/// greater than zero, n must be greater than
/// or equal to zero and less than or equal
/// to max.
~Semaphore();
/// Destroys the semaphore.
void set();
/// Increments the semaphore's value by one and
/// thus signals the semaphore. Another thread
/// waiting for the semaphore will be able
/// to continue.
void wait();
/// Waits for the semaphore to become signalled.
/// To become signalled, a semaphore's value must
/// be greater than zero.
/// Decrements the semaphore's value by one.
void wait(long milliseconds);
/// Waits for the semaphore to become signalled.
/// To become signalled, a semaphore's value must
/// be greater than zero.
/// Throws a TimeoutException if the semaphore
/// does not become signalled within the specified
/// time interval.
/// Decrements the semaphore's value by one
/// if successful.
bool tryWait(long milliseconds);
/// Waits for the semaphore to become signalled.
/// To become signalled, a semaphore's value must
/// be greater than zero.
/// Returns true if the semaphore
/// became signalled within the specified
/// time interval, false otherwise.
/// Decrements the semaphore's value by one
/// if successful.
private:
Semaphore();
Semaphore(const Semaphore&);
Semaphore& operator = (const Semaphore&);
};
//
// inlines
//
inline void Semaphore::set()
{
setImpl();
}
inline void Semaphore::wait()
{
waitImpl();
}
inline void Semaphore::wait(long milliseconds)
{
if (!waitImpl(milliseconds))
throw TimeoutException();
}
inline bool Semaphore::tryWait(long milliseconds)
{
return waitImpl(milliseconds);
}
} // namespace Poco
#endif // Foundation_Semaphore_INCLUDED
|