Merge "Improve DataSource interface."
diff --git a/tools/signapk/src/com/android/signapk/SignApk.java b/tools/signapk/src/com/android/signapk/SignApk.java
index 1df6b80..a7c9fc3 100644
--- a/tools/signapk/src/com/android/signapk/SignApk.java
+++ b/tools/signapk/src/com/android/signapk/SignApk.java
@@ -52,6 +52,7 @@
import java.io.PrintStream;
import java.lang.reflect.Constructor;
import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
import java.security.DigestOutputStream;
import java.security.GeneralSecurityException;
import java.security.InvalidKeyException;
@@ -119,6 +120,19 @@
private static final String OTACERT_NAME = "META-INF/com/android/otacert";
+ /**
+ * Extensible data block/field header ID used for storing information about alignment of
+ * uncompressed entries as well as for aligning the entries's data. See ZIP appnote.txt section
+ * 4.5 Extensible data fields.
+ */
+ private static final short ALIGNMENT_ZIP_EXTRA_DATA_FIELD_HEADER_ID = (short) 0xd935;
+
+ /**
+ * Minimum size (in bytes) of the extensible data block/field used for alignment of uncompressed
+ * entries.
+ */
+ private static final short ALIGNMENT_ZIP_EXTRA_DATA_FIELD_MIN_SIZE_BYTES = 6;
+
// bitmasks for which hash algorithms we need the manifest to include.
private static final int USE_SHA1 = 1;
private static final int USE_SHA256 = 2;
@@ -588,28 +602,40 @@
outEntry.setComment(null);
outEntry.setExtra(null);
- // 'offset' is the offset into the file at which we expect
- // the file data to begin. This is the value we need to
- // make a multiple of 'alignement'.
+ int alignment = getStoredEntryDataAlignment(name, defaultAlignment);
+ // Alignment of the entry's data is achieved by adding a data block to the entry's Local
+ // File Header extra field. The data block contains information about the alignment
+ // value and the necessary padding bytes (0x00) to achieve the alignment. This works
+ // because the entry's data will be located immediately after the extra field.
+ // See ZIP APPNOTE.txt section "4.5 Extensible data fields" for details about the format
+ // of the extra field.
+
+ // 'offset' is the offset into the file at which we expect the entry's data to begin.
+ // This is the value we need to make a multiple of 'alignment'.
offset += JarFile.LOCHDR + outEntry.getName().length();
if (firstEntry) {
- // The first entry in a jar file has an extra field of
- // four bytes that you can't get rid of; any extra
- // data you specify in the JarEntry is appended to
- // these forced four bytes. This is JAR_MAGIC in
- // JarOutputStream; the bytes are 0xfeca0000.
+ // The first entry in a jar file has an extra field of four bytes that you can't get
+ // rid of; any extra data you specify in the JarEntry is appended to these forced
+ // four bytes. This is JAR_MAGIC in JarOutputStream; the bytes are 0xfeca0000.
+ // See http://bugs.java.com/bugdatabase/view_bug.do?bug_id=6808540
+ // and http://bugs.java.com/bugdatabase/view_bug.do?bug_id=4138619.
offset += 4;
firstEntry = false;
}
- int alignment = getStoredEntryDataAlignment(name, defaultAlignment);
- if (alignment > 0 && (offset % alignment != 0)) {
- // Set the "extra data" of the entry to between 1 and
- // alignment-1 bytes, to make the file data begin at
- // an aligned offset.
- int needed = alignment - (int)(offset % alignment);
- outEntry.setExtra(new byte[needed]);
- offset += needed;
+ int extraPaddingSizeBytes = 0;
+ if (alignment > 0) {
+ long paddingStartOffset = offset + ALIGNMENT_ZIP_EXTRA_DATA_FIELD_MIN_SIZE_BYTES;
+ extraPaddingSizeBytes = alignment - (int) (paddingStartOffset % alignment);
}
+ byte[] extra =
+ new byte[ALIGNMENT_ZIP_EXTRA_DATA_FIELD_MIN_SIZE_BYTES + extraPaddingSizeBytes];
+ ByteBuffer extraBuf = ByteBuffer.wrap(extra);
+ extraBuf.order(ByteOrder.LITTLE_ENDIAN);
+ extraBuf.putShort(ALIGNMENT_ZIP_EXTRA_DATA_FIELD_HEADER_ID); // Header ID
+ extraBuf.putShort((short) (2 + extraPaddingSizeBytes)); // Data Size
+ extraBuf.putShort((short) alignment);
+ outEntry.setExtra(extra);
+ offset += extra.length;
out.putNextEntry(outEntry);