public static Chunk Get(BinaryReader input)
{
if ((input.BaseStream.Remaining()) < HeaderMinSizeBytes)
{
// Android ignores the last chunk if its header is too big to fit into the file
input.BaseStream.Position = input.BaseStream.Length;
return(null);
}
long originalPosition = input.BaseStream.Position;
int type = input.ReadUInt16();
int headerSize = input.ReadUInt16();
long chunkSize = input.ReadUInt32();
long chunkRemaining = chunkSize - 8;
if (chunkRemaining > input.BaseStream.Remaining())
{
// Android ignores the last chunk if it's too big to fit into the file
input.BaseStream.Position = input.BaseStream.Length;
return(null);
}
if (headerSize < HeaderMinSizeBytes)
{
throw new FormatException(
"Malformed chunk: header too short: " + headerSize + " bytes");
}
else if (headerSize > chunkSize)
{
throw new FormatException(
"Malformed chunk: header too long: " + headerSize + " bytes. Chunk size: "
+ chunkSize + " bytes");
}
long contentStartPosition = originalPosition + headerSize;
long chunkEndPosition = originalPosition + chunkSize;
Chunk chunk =
new Chunk(
type,
AndroidBinXmlParser.SliceFromTo(input.BaseStream, originalPosition, contentStartPosition),
AndroidBinXmlParser.SliceFromTo(input.BaseStream, contentStartPosition, chunkEndPosition));
input.BaseStream.Position = chunkEndPosition;
return(chunk);
}
/// <summary>
/// Returns the lowest Android platform version (API Level) supported by an APK with the
/// provided <code>AndroidManifest.xml</code>
/// </summary>
/// <param name="androidManifest">contents of <code>AndroidManifest.xml</code> in binary Android resource format</param>
/// <returns></returns>
public static int GetMinSdkVersionFromBinaryAndroidManifest(byte[] androidManifest)
{
// IMPLEMENTATION NOTE: Minimum supported Android platform version number is declared using
// uses-sdk elements which are children of the top-level manifest element. uses-sdk element
// declares the minimum supported platform version using the android:minSdkVersion attribute
// whose default value is 1.
// For each encountered uses-sdk element, the Android runtime checks that its minSdkVersion
// is not higher than the runtime's API Level and rejects APKs if it is higher. Thus, the
// effective minSdkVersion value is the maximum over the encountered minSdkVersion values.
try
{
// If no uses-sdk elements are encountered, Android accepts the APK. We treat this
// scenario as though the minimum supported API Level is 1.
int result = 1;
AndroidBinXmlParser parser = new AndroidBinXmlParser(androidManifest);
var eventType = parser.EventType;
while (eventType != AndroidBinXmlParser.EndOfDocument)
{
if ((eventType == AndroidBinXmlParser.EventStartElement) &&
(parser.Depth == 2) &&
("uses-sdk" == parser.Name) &&
(String.IsNullOrEmpty(parser.Namespace)))
{
// In each uses-sdk element, minSdkVersion defaults to 1
int minSdkVersion = 1;
for (int i = 0; i < parser.AttributeCount; i++)
{
if (parser.GetAttributeNameResourceId(i) == MinSdkVersionAttrId)
{
int valueType = parser.GetAttributeValueType(i);
switch (valueType)
{
case AndroidBinXmlParser.ValueTypeInt:
minSdkVersion = parser.GetAttributeIntValue(i);
break;
case AndroidBinXmlParser.ValueTypeString:
minSdkVersion = GetMinSdkVersionForCodename(parser.GetAttributeStringValue(i));
break;
default:
throw new FormatException(
"Unable to determine APK's minimum supported Android"
+ ": unsupported value type in "
+ AndroidManifestZipEntryName + "'s"
+ " minSdkVersion"
+ ". Only integer values supported.");
}
break;
}
}
result = Math.Max(result, minSdkVersion);
}
eventType = parser.Next();
}
return(result);
}
catch (Exception e)
{
throw new FormatException(
"Unable to determine APK's minimum supported Android platform version"
+ ": malformed binary resource: " + AndroidManifestZipEntryName,
e);
}
}
