fprime/Utils/TokenBucket.cpp
2025-09-10 15:02:07 -07:00

95 lines
2.7 KiB
C++

// ======================================================================
// \title TokenBucket.cpp
// \author vwong
// \brief cpp file for a rate limiter utility class
//
// \copyright
//
// Copyright (C) 2009-2020 California Institute of Technology.
//
// ALL RIGHTS RESERVED. United States Government Sponsorship
// acknowledged.
// ======================================================================
#include <Utils/TokenBucket.hpp>
namespace Utils {
TokenBucket ::TokenBucket(U32 replenishInterval, U32 maxTokens, U32 replenishRate, U32 startTokens, Fw::Time startTime)
: m_replenishInterval(replenishInterval),
m_maxTokens(maxTokens),
m_replenishRate(replenishRate),
m_tokens(startTokens),
m_time(startTime) {}
TokenBucket ::TokenBucket(U32 replenishInterval, U32 maxTokens)
: m_replenishInterval(replenishInterval),
m_maxTokens(maxTokens),
m_replenishRate(1),
m_tokens(maxTokens),
m_time(0, 0) {
FW_ASSERT(this->m_maxTokens <= MAX_TOKEN_BUCKET_TOKENS, static_cast<FwAssertArgType>(this->m_maxTokens));
}
void TokenBucket ::setReplenishInterval(U32 replenishInterval) {
this->m_replenishInterval = replenishInterval;
}
void TokenBucket ::setMaxTokens(U32 maxTokens) {
this->m_maxTokens = maxTokens;
}
void TokenBucket ::setReplenishRate(U32 replenishRate) {
this->m_replenishRate = replenishRate;
}
void TokenBucket ::replenish() {
if (this->m_tokens < this->m_maxTokens) {
this->m_tokens = this->m_maxTokens;
}
}
U32 TokenBucket ::getReplenishInterval() const {
return this->m_replenishInterval;
}
U32 TokenBucket ::getMaxTokens() const {
return this->m_maxTokens;
}
U32 TokenBucket ::getReplenishRate() const {
return this->m_replenishRate;
}
U32 TokenBucket ::getTokens() const {
return this->m_tokens;
}
bool TokenBucket ::trigger(const Fw::Time time) {
// attempt replenishing
if (this->m_replenishRate > 0) {
Fw::Time replenishInterval = Fw::Time(this->m_replenishInterval / 1000000, this->m_replenishInterval % 1000000);
Fw::Time nextTime = Fw::Time::add(this->m_time, replenishInterval);
while (this->m_tokens < this->m_maxTokens && nextTime <= time) {
// replenish by replenish rate, or up to maxTokens
this->m_tokens += FW_MIN(this->m_replenishRate, this->m_maxTokens - this->m_tokens);
this->m_time = nextTime;
nextTime = Fw::Time::add(this->m_time, replenishInterval);
}
if (this->m_tokens >= this->m_maxTokens && this->m_time < time) {
this->m_time = time;
}
}
// attempt consuming token
if (this->m_tokens > 0) {
this->m_tokens--;
return true;
} else {
return false;
}
}
} // end namespace Utils