[libvirt] [libvirt-java] [PATCH] Fix wrapping of native size_t data type

Libvirt function parameters having type (pointer to) size_t were wrapped via JNA using int, long or even NativeLong. Alas, none of these is actually correct as the size of size_t may be the same as the size of either (unsigned) int, long or even long long on different platforms. JNA provides the size of a native size_t to us, so using this information we define and use class SizeT and class SizeTByReference for wrapping a native size_t and size_t*, respectively. Signed-off-by: Claudio Bley <cbley(a)av-test.de&gt; --- src/main/java/org/libvirt/Domain.java | 5 ++-- src/main/java/org/libvirt/Secret.java | 10 ++++---- src/main/java/org/libvirt/Stream.java | 7 +++-- src/main/java/org/libvirt/jna/Libvirt.java | 14 +++++----- src/main/java/org/libvirt/jna/SizeT.java | 25 ++++++++++++++++++ .../java/org/libvirt/jna/SizeTByReference.java | 27 ++++++++++++++++++++ 6 files changed, 70 insertions(+), 18 deletions(-) create mode 100644 src/main/java/org/libvirt/jna/SizeT.java create mode 100644 src/main/java/org/libvirt/jna/SizeTByReference.java diff --git a/src/main/java/org/libvirt/Domain.java b/src/main/java/org/libvirt/Domain.java index a72e8c6..efac9b9 100644 --- a/src/main/java/org/libvirt/Domain.java +++ b/src/main/java/org/libvirt/Domain.java @@ -3,6 +3,7 @@ package org.libvirt; import org.libvirt.jna.DomainPointer; import org.libvirt.jna.DomainSnapshotPointer; import org.libvirt.jna.Libvirt; +import org.libvirt.jna.SizeT; import org.libvirt.jna.virDomainBlockInfo; import org.libvirt.jna.virDomainBlockStats; import org.libvirt.jna.virDomainInfo; @@ -234,7 +235,7 @@ public class Domain { */ public DomainBlockStats blockStats(String path) throws LibvirtException { virDomainBlockStats stats = new virDomainBlockStats(); - int success = libvirt.virDomainBlockStats(VDP, path, stats, stats.size()); + int success = libvirt.virDomainBlockStats(VDP, path, stats, new SizeT(stats.size())); processError(); return success == 0 ? new DomainBlockStats(stats) : null; } @@ -695,7 +696,7 @@ public class Domain { */ public DomainInterfaceStats interfaceStats(String path) throws LibvirtException { virDomainInterfaceStats stats = new virDomainInterfaceStats(); - libvirt.virDomainInterfaceStats(VDP, path, stats, stats.size()); + libvirt.virDomainInterfaceStats(VDP, path, stats, new SizeT(stats.size())); processError(); return new DomainInterfaceStats(stats); } diff --git a/src/main/java/org/libvirt/Secret.java b/src/main/java/org/libvirt/Secret.java index 5332e02..4edb515 100644 --- a/src/main/java/org/libvirt/Secret.java +++ b/src/main/java/org/libvirt/Secret.java @@ -2,11 +2,11 @@ package org.libvirt; import org.libvirt.jna.Libvirt; import org.libvirt.jna.SecretPointer; +import org.libvirt.jna.SizeT; +import org.libvirt.jna.SizeTByReference; import static org.libvirt.Library.libvirt; import com.sun.jna.Native; -import com.sun.jna.NativeLong; -import com.sun.jna.ptr.LongByReference; import com.sun.jna.Pointer; import java.nio.ByteBuffer; @@ -120,7 +120,7 @@ public class Secret { * @return the value of the secret, or null on failure. */ public byte[] getByteValue() throws LibvirtException { - LongByReference value_size = new LongByReference(); + SizeTByReference value_size = new SizeTByReference(); Pointer value = libvirt.virSecretGetValue(VSP, value_size, 0); processError(); ByteBuffer bb = value.getByteBuffer(0, value_size.getValue()); @@ -154,7 +154,7 @@ public class Secret { * @return 0 on success, -1 on failure. */ public int setValue(String value) throws LibvirtException { - int returnValue = libvirt.virSecretSetValue(VSP, value, new NativeLong(value.length()), 0); + int returnValue = libvirt.virSecretSetValue(VSP, value, new SizeT(value.length()), 0); processError(); return returnValue; } @@ -165,7 +165,7 @@ public class Secret { * @return 0 on success, -1 on failure. */ public int setValue(byte[] value) throws LibvirtException { - int returnValue = libvirt.virSecretSetValue(VSP, value, new NativeLong(value.length), 0); + int returnValue = libvirt.virSecretSetValue(VSP, value, new SizeT(value.length), 0); processError(); return returnValue; } diff --git a/src/main/java/org/libvirt/Stream.java b/src/main/java/org/libvirt/Stream.java index 84e300c..d852d0d 100644 --- a/src/main/java/org/libvirt/Stream.java +++ b/src/main/java/org/libvirt/Stream.java @@ -1,11 +1,10 @@ package org.libvirt; import org.libvirt.jna.Libvirt; +import org.libvirt.jna.SizeT; import org.libvirt.jna.StreamPointer; import static org.libvirt.Library.libvirt; -import com.sun.jna.NativeLong; - public class Stream { public static int VIR_STREAM_NONBLOCK = (1 << 0); @@ -108,7 +107,7 @@ public class Stream { * @throws LibvirtException */ public int receive(byte[] data) throws LibvirtException { - int returnValue = libvirt.virStreamRecv(VSP, data, new NativeLong(data.length)); + int returnValue = libvirt.virStreamRecv(VSP, data, new SizeT(data.length)); processError(); return returnValue; } @@ -151,7 +150,7 @@ public class Stream { * @throws LibvirtException */ public int send(String data) throws LibvirtException { - int returnValue = libvirt.virStreamSend(VSP, data, new NativeLong(data.length())); + int returnValue = libvirt.virStreamSend(VSP, data, new SizeT(data.length())); processError(); return returnValue; } diff --git a/src/main/java/org/libvirt/jna/Libvirt.java b/src/main/java/org/libvirt/jna/Libvirt.java index 8c7d6ef..34ef966 100644 --- a/src/main/java/org/libvirt/jna/Libvirt.java +++ b/src/main/java/org/libvirt/jna/Libvirt.java @@ -180,7 +180,7 @@ public interface Libvirt extends Library { int virDomainAbortJob(DomainPointer virDomainPtr); int virDomainAttachDevice(DomainPointer virDomainPtr, String deviceXML); int virDomainAttachDeviceFlags(DomainPointer virDomainPtr, String deviceXML, int flags); - int virDomainBlockStats(DomainPointer virDomainPtr, String path, virDomainBlockStats stats, int size); + int virDomainBlockStats(DomainPointer virDomainPtr, String path, virDomainBlockStats stats, SizeT size); int virDomainBlockResize(DomainPointer virDomainPtr, String disk, long size, int flags); int virDomainCoreDump(DomainPointer virDomainPtr, String to, int flags); int virDomainCreate(DomainPointer virDomainPtr); @@ -210,7 +210,7 @@ public interface Libvirt extends Library { Pointer virDomainGetXMLDesc(DomainPointer virDomainPtr, int flags); int virDomainHasCurrentSnapshot(DomainPointer virDomainPtr, int flags); int virDomainHasManagedSaveImage(DomainPointer virDomainPtr, int flags); - int virDomainInterfaceStats(DomainPointer virDomainPtr, String path, virDomainInterfaceStats stats, int size); + int virDomainInterfaceStats(DomainPointer virDomainPtr, String path, virDomainInterfaceStats stats, SizeT size); int virDomainIsActive(DomainPointer virDomainPtr); int virDomainIsPersistent(DomainPointer virDomainPtr); DomainPointer virDomainLookupByID(ConnectionPointer virConnectPtr, int id); @@ -351,13 +351,13 @@ public interface Libvirt extends Library { int virSecretGetUUID(SecretPointer virSecretPtr, byte[] uuidString); int virSecretGetUUIDString(SecretPointer virSecretPtr, byte[] uuidString); String virSecretGetUsageID(SecretPointer virSecretPtr); - Pointer virSecretGetValue(SecretPointer virSecretPtr, LongByReference value_size, int flags); + Pointer virSecretGetValue(SecretPointer virSecretPtr, SizeTByReference value_size, int flags); String virSecretGetXMLDesc(SecretPointer virSecretPtr, int flags); SecretPointer virSecretLookupByUsage(ConnectionPointer virConnectPtr, int usageType, String usageID); SecretPointer virSecretLookupByUUID(ConnectionPointer virConnectPtr, byte[] uuidBytes); SecretPointer virSecretLookupByUUIDString(ConnectionPointer virConnectPtr, String uuidstr); - int virSecretSetValue(SecretPointer virSecretPtr, String value, NativeLong value_size, int flags); - int virSecretSetValue(SecretPointer virSecretPtr, byte[] value, NativeLong value_size, int flags); + int virSecretSetValue(SecretPointer virSecretPtr, String value, SizeT value_size, int flags); + int virSecretSetValue(SecretPointer virSecretPtr, byte[] value, SizeT value_size, int flags); int virSecretUndefine(SecretPointer virSecretPtr); //Stream Methods @@ -369,9 +369,9 @@ public interface Libvirt extends Library { int virStreamFinish(StreamPointer virStreamPtr) ; int virStreamFree(StreamPointer virStreamPtr) ; StreamPointer virStreamNew(ConnectionPointer virConnectPtr, int flags) ; - int virStreamSend(StreamPointer virStreamPtr, String data, NativeLong size); + int virStreamSend(StreamPointer virStreamPtr, String data, SizeT size); int virStreamSendAll(StreamPointer virStreamPtr, Libvirt.VirStreamSourceFunc handler, Pointer opaque); - int virStreamRecv(StreamPointer virStreamPtr, byte[] data, NativeLong length); + int virStreamRecv(StreamPointer virStreamPtr, byte[] data, SizeT length); int virStreamRecvAll(StreamPointer virStreamPtr, Libvirt.VirStreamSinkFunc handler, Pointer opaque); //DomainSnapshot Methods diff --git a/src/main/java/org/libvirt/jna/SizeT.java b/src/main/java/org/libvirt/jna/SizeT.java new file mode 100644 index 0000000..298fe73 --- /dev/null +++ b/src/main/java/org/libvirt/jna/SizeT.java @@ -0,0 +1,25 @@ +package org.libvirt.jna; + +import com.sun.jna.Native; +import com.sun.jna.IntegerType; + +/** + * Represents the native {@code size_t} data type. + */ +public final class SizeT extends IntegerType { + public SizeT() { this(0); } + public SizeT(long value) { + /* N.B. A three argument constructor is supported starting with + * JNA version 3.4.1. + * + * The third argument determines whether this class represents + * an unsigned integer type. When extracting a value into a + * larger-sized container (e.g. 4 byte native type into Java + * long), the value is properly converted as unsigned. + * + * TODO: Use this constructor once we require JNA >= 3.4.1 + */ + // super(Native.SIZE_T_SIZE, value, true); + super(Native.SIZE_T_SIZE, value); + } +} diff --git a/src/main/java/org/libvirt/jna/SizeTByReference.java b/src/main/java/org/libvirt/jna/SizeTByReference.java new file mode 100644 index 0000000..63fe453 --- /dev/null +++ b/src/main/java/org/libvirt/jna/SizeTByReference.java @@ -0,0 +1,27 @@ +package org.libvirt.jna; + +import com.sun.jna.Native; +import com.sun.jna.ptr.ByReference; + +/** + * Represents a native (call-by-reference) pointer to {@code size_t} data type. + */ +public final class SizeTByReference extends ByReference { + public SizeTByReference() { + this(0); + } + + public SizeTByReference(long value) { + super(Native.SIZE_T_SIZE); + setValue(value); + } + + public void setValue(long value) { + getPointer().setLong(0, value); + } + + public long getValue() { + return getPointer().getLong(0); + } + +} -- 1.7.9.5