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Fix Range-Checking in CellSignalStrengthCdma

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The CellSignalStrengthCdma class previously allowed
the values in the class to be kept as negative ints
but expected them to be parceled as positive ints.
This led to a confusing mess that is best unwound
by calling the actual constructor for the class and
letting the parcel values be an implementation detail.
This CL removes all of the parcel-time coersion and
instead expects that the class be constructed using
a constructor rather than by manually parceling and
then using the class to un-parcel. In addition, the
range checking for inputs is now done only once, and
values are no longer mutated in the parcel/unparcel
process.

Bug: 32364031
Test: runtest frameworks-telephony
Change-Id: I59ce8c9df1bd99547f3de941a30d6c3cea8f2b8f
This commit is contained in:
Nathan Harold
2018-02-26 19:14:18 -08:00
parent 95500f8a0f
commit 3ffbf86e1e
1 changed files with 32 additions and 17 deletions
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49
telephony/java/android/telephony/CellSignalStrengthCdma.java
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@@ -41,14 +41,36 @@ public final class CellSignalStrengthCdma extends CellSignalStrength implements
setDefaultValues();
}
/** @hide */
/**
* SignalStrength constructor for input from the HAL.
*
* Note that values received from the HAL require coersion to be compatible here. All values
* reported through IRadio are the negative of the actual values (which results in a positive
* input to this method.
*
* <p>Note that this HAL is inconsistent with UMTS-based radio techs as the value indicating
* that a field is unreported is negative, rather than a large(r) positive number.
* <p>Also note that to keep the public-facing methods of this class consistent with others,
* unreported values are coerced to Integer.MAX_VALUE rather than left as -1, which is
* a departure from SignalStrength, which is stuck with the values it currently reports.
*
* @param cdmaDbm negative of the CDMA signal strength value or -1 if invalid.
* @param cdmaEcio negative of the CDMA pilot/noise ratio or -1 if invalid.
* @param evdoDbm negative of the EvDO signal strength value or -1 if invalid.
* @param evdoEcio negative of the EvDO pilot/noise ratio or -1 if invalid.
* @param evdoSnr an SNR value 0..8 or -1 if invalid.
* @hide
*/
public CellSignalStrengthCdma(int cdmaDbm, int cdmaEcio, int evdoDbm, int evdoEcio,
int evdoSnr) {
mCdmaDbm = cdmaDbm;
mCdmaEcio = cdmaEcio;
mEvdoDbm = evdoDbm;
mEvdoEcio = evdoEcio;
mEvdoSnr = evdoSnr;
// The values here were lifted from SignalStrength.validateInput()
// FIXME: Combine all checking and setting logic between this and SignalStrength.
mCdmaDbm = ((cdmaDbm > 0) && (cdmaDbm < 120)) ? -cdmaDbm : Integer.MAX_VALUE;
mCdmaEcio = ((cdmaEcio > 0) && (cdmaEcio < 160)) ? -cdmaEcio : Integer.MAX_VALUE;
mEvdoDbm = ((evdoDbm > 0) && (evdoDbm < 120)) ? -evdoDbm : Integer.MAX_VALUE;
mEvdoEcio = ((evdoEcio > 0) && (evdoEcio < 160)) ? -evdoEcio : Integer.MAX_VALUE;
mEvdoSnr = ((evdoSnr > 0) && (evdoSnr <= 8)) ? evdoSnr : Integer.MAX_VALUE;
}
/** @hide */
@@ -303,13 +325,10 @@ public final class CellSignalStrengthCdma extends CellSignalStrength implements
@Override
public void writeToParcel(Parcel dest, int flags) {
if (DBG) log("writeToParcel(Parcel, int): " + toString());
// Need to multiply CdmaDbm, CdmaEcio, EvdoDbm and EvdoEcio by -1
// to ensure consistency when reading values written here
// unless the value is invalid
dest.writeInt(mCdmaDbm * (mCdmaDbm != Integer.MAX_VALUE ? -1 : 1));
dest.writeInt(mCdmaEcio * (mCdmaEcio != Integer.MAX_VALUE ? -1 : 1));
dest.writeInt(mEvdoDbm * (mEvdoDbm != Integer.MAX_VALUE ? -1 : 1));
dest.writeInt(mEvdoEcio * (mEvdoEcio != Integer.MAX_VALUE ? -1 : 1));
dest.writeInt(mCdmaDbm);
dest.writeInt(mCdmaEcio);
dest.writeInt(mEvdoDbm);
dest.writeInt(mEvdoEcio);
dest.writeInt(mEvdoSnr);
}
@@ -322,13 +341,9 @@ public final class CellSignalStrengthCdma extends CellSignalStrength implements
// the parcel as positive values.
// Need to convert into negative values unless the value is invalid
mCdmaDbm = in.readInt();
if (mCdmaDbm != Integer.MAX_VALUE) mCdmaDbm *= -1;
mCdmaEcio = in.readInt();
if (mCdmaEcio != Integer.MAX_VALUE) mCdmaEcio *= -1;
mEvdoDbm = in.readInt();
if (mEvdoDbm != Integer.MAX_VALUE) mEvdoDbm *= -1;
mEvdoEcio = in.readInt();
if (mEvdoEcio != Integer.MAX_VALUE) mEvdoEcio *= -1;
mEvdoSnr = in.readInt();
if (DBG) log("CellSignalStrengthCdma(Parcel): " + toString());
}