sc_semaphore.cc

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/*
 * Copyright 2018 Google, Inc.
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 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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#include <string>
 
#include "systemc/ext/channel/messages.hh"
#include "systemc/ext/channel/sc_semaphore.hh"
#include "systemc/ext/core/sc_module.hh" // for sc_gen_unique_name
#include "systemc/ext/utils/sc_report_handler.hh"
 
namespace sc_core
{
 
sc_semaphore::sc_semaphore(int value) :
    sc_semaphore(sc_gen_unique_name("semaphore"), value)
{}
 
sc_semaphore::sc_semaphore(const char *_name, int value) :
        sc_interface(), sc_semaphore_if(), sc_object(_name), _value(value)
{
    if (value < 0) {
        std::string msg = "semaphore '" + std::string(name()) + "'";
        SC_REPORT_ERROR(SC_ID_INVALID_SEMAPHORE_VALUE_, msg.c_str());
    }
}
 
int
sc_semaphore::wait()
{
    while (trywait() == -1)
        ::sc_core::wait(posted);
    return 0;
}
 
int
sc_semaphore::trywait()
{
    if (!_value)
        return -1;
 
    _value--;
    return 0;
}
 
int
sc_semaphore::post()
{
    if (_value++ == 0)
        posted.notify();
    return 0;
}
 
int sc_semaphore::get_value() const { return _value; }
 
} // namespace sc_core