`LinkQualityInfo`: Ensure not to add an invalid/unknown RSS to average. (#1594)
This commit also fixes some of the argument variable names in
`LinkQualityInfo` class.
diff --git a/src/core/thread/link_quality.cpp b/src/core/thread/link_quality.cpp
index 2ceeaff..a6f0cf0 100644
--- a/src/core/thread/link_quality.cpp
+++ b/src/core/thread/link_quality.cpp
@@ -76,23 +76,25 @@
mLastRss = 0;
}
-void LinkQualityInfo::AddRss(LinkQualityInfo &aNoiseFloor, int8_t anRss)
+void LinkQualityInfo::AddRss(LinkQualityInfo &aNoiseFloor, int8_t aRss)
{
uint16_t newValue;
uint16_t oldAverage;
- mLastRss = anRss;
+ VerifyOrExit(aRss != kUnknownRss);
+
+ mLastRss = aRss;
// Restrict/Cap the RSS value to the closed range [0, -128] so the value can fit in 8 bits.
- if (anRss > 0)
+ if (aRss > 0)
{
- anRss = 0;
+ aRss = 0;
}
// Multiply the the RSS value by a precision multiple (currently -8).
- newValue = static_cast<uint16_t>(-anRss);
+ newValue = static_cast<uint16_t>(-aRss);
newValue <<= kRssAveragePrecisionMultipleBitShift;
oldAverage = mRssAverage;
@@ -123,6 +125,9 @@
}
UpdateLinkQuality(aNoiseFloor);
+
+exit:
+ return;
}
int8_t LinkQualityInfo::GetAverageRss(void) const
@@ -202,11 +207,11 @@
}
}
-uint8_t LinkQualityInfo::ConvertRssToLinkMargin(LinkQualityInfo &aNoiseFloor, int8_t anRss)
+uint8_t LinkQualityInfo::ConvertRssToLinkMargin(LinkQualityInfo &aNoiseFloor, int8_t aRss)
{
- int8_t linkMargin = anRss - GetAverageNoiseFloor(aNoiseFloor);
+ int8_t linkMargin = aRss - GetAverageNoiseFloor(aNoiseFloor);
- if (linkMargin < 0 || anRss == kUnknownRss)
+ if (linkMargin < 0 || aRss == kUnknownRss)
{
linkMargin = 0;
}
@@ -219,9 +224,9 @@
return CalculateLinkQuality(aLinkMargin, kNoLastLinkQualityValue);
}
-uint8_t LinkQualityInfo::ConvertRssToLinkQuality(LinkQualityInfo &aNoiseFloor, int8_t anRss)
+uint8_t LinkQualityInfo::ConvertRssToLinkQuality(LinkQualityInfo &aNoiseFloor, int8_t aRss)
{
- return ConvertLinkMarginToLinkQuality(ConvertRssToLinkMargin(aNoiseFloor, anRss));
+ return ConvertLinkMarginToLinkQuality(ConvertRssToLinkMargin(aNoiseFloor, aRss));
}
uint8_t LinkQualityInfo::CalculateLinkQuality(uint8_t aLinkMargin, uint8_t aLastLinkQuality)
diff --git a/src/core/thread/link_quality.hpp b/src/core/thread/link_quality.hpp
index 749c416..6458c83 100644
--- a/src/core/thread/link_quality.hpp
+++ b/src/core/thread/link_quality.hpp
@@ -77,10 +77,10 @@
* This method adds a new received signal strength (RSS) value to the average.
*
* @param[in] aNoiseFloor A reference to the noise floor state.
- * @param[in] anRss A new received signal strength value (in dBm) to be added to the average.
+ * @param[in] aRss A new received signal strength value (in dBm) to be added to the average.
*
*/
- void AddRss(LinkQualityInfo &aNoiseFloor, int8_t anRss);
+ void AddRss(LinkQualityInfo &aNoiseFloor, int8_t aRss);
/**
* This method returns the current average signal strength value.
@@ -152,12 +152,12 @@
* This method converts a received signal strength value to a link margin value.
*
* @param[in] aNoiseFloor A reference to the noise state.
- * @param[in] anRss The received signal strength value (in dBm).
+ * @param[in] aRss The received signal strength value (in dBm).
*
* @returns The link margin value.
*
*/
- static uint8_t ConvertRssToLinkMargin(LinkQualityInfo &aNoiseFloor, int8_t anRss);
+ static uint8_t ConvertRssToLinkMargin(LinkQualityInfo &aNoiseFloor, int8_t aRss);
/**
* This method converts a link margin value to a link quality value.
@@ -173,12 +173,12 @@
* This method converts a received signal strength value to a link quality value.
*
* @param[in] aNoiseFloor A reference to the noise state.
- * @param[in] anRss The received signal strength value (in dBm).
+ * @param[in] aRss The received signal strength value (in dBm).
*
* @returns The link quality value (0-3).
*
*/
- static uint8_t ConvertRssToLinkQuality(LinkQualityInfo &aNoiseFloor, int8_t anRss);
+ static uint8_t ConvertRssToLinkQuality(LinkQualityInfo &aNoiseFloor, int8_t aRss);
private:
enum
