8074694: Lazy conversion of ZipEntry time

Summary: to backport the same fix to 8u
Reviewed-by: sherman
Contributed-by: claes.redestad@oracle.com

src/share/classes/java/util/zip/ZipEntry.java

 /*
- * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1995, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -41,7 +41,9 @@ public
 class ZipEntry implements ZipConstants, Cloneable {
 
     String name;        // entry name
-    long time = -1;     // last modification time
+    long xdostime = -1; // last modification time (in extended DOS time,
+                        // where milliseconds lost in conversion might
+                        // be encoded into the upper half)
     FileTime mtime;     // last modification time, from extra field data
     FileTime atime;     // last access time, from extra field data
     FileTime ctime;     // creation time, from extra field data
@@ -63,6 +65,28 @@ class ZipEntry implements ZipConstants, Cloneable {
      */
     public static final int DEFLATED = 8;
 
+    /**
+     * DOS time constant for representing timestamps before 1980.
+     */
+    static final long DOSTIME_BEFORE_1980 = (1 << 21) | (1 << 16);
+
+    /**
+     * Approximately 128 years, in milliseconds (ignoring leap years etc).
+     *
+     * This establish an approximate high-bound value for DOS times in
+     * milliseconds since epoch, used to enable an efficient but
+     * sufficient bounds check to avoid generating extended last modified
+     * time entries.
+     *
+     * Calculating the exact number is locale dependent, would require loading
+     * TimeZone data eagerly, and would make little practical sense. Since DOS
+     * times theoretically go to 2107 - with compatibility not guaranteed
+     * after 2099 - setting this to a time that is before but near 2099
+     * should be sufficient.
+     */
+    private static final long UPPER_DOSTIME_BOUND =
+            128L * 365 * 24 * 60 * 60 * 1000;
+
     /**
      * Creates a new zip entry with the specified name.
      *
@@ -93,7 +117,7 @@ class ZipEntry implements ZipConstants, Cloneable {
     public ZipEntry(ZipEntry e) {
         Objects.requireNonNull(e, "entry");
         name = e.name;
-        time = e.time;
+        xdostime = e.xdostime;
         mtime = e.mtime;
         atime = e.atime;
         ctime = e.ctime;
@@ -137,8 +161,14 @@ class ZipEntry implements ZipConstants, Cloneable {
      * @see #getLastModifiedTime()
      */
     public void setTime(long time) {
-        this.time = time;
+        this.xdostime = javaToExtendedDosTime(time);
+        // Avoid setting the mtime field if time is in the valid
+        // range for a DOS time
+        if (xdostime != DOSTIME_BEFORE_1980 && time <= UPPER_DOSTIME_BOUND) {
             this.mtime = null;
+        } else {
+            this.mtime = FileTime.from(time, TimeUnit.MILLISECONDS);
+        }
     }
 
     /**
@@ -158,7 +188,10 @@ class ZipEntry implements ZipConstants, Cloneable {
      * @see #setLastModifiedTime(FileTime)
      */
     public long getTime() {
-        return time;
+        if (mtime != null) {
+            return mtime.toMillis();
+        }
+        return (xdostime != -1) ? extendedDosToJavaTime(xdostime) : -1;
     }
 
     /**
@@ -181,7 +214,7 @@ class ZipEntry implements ZipConstants, Cloneable {
      */
     public ZipEntry setLastModifiedTime(FileTime time) {
         this.mtime = Objects.requireNonNull(time, "lastModifiedTime");
-        this.time = time.to(TimeUnit.MILLISECONDS);
+        this.xdostime = javaToExtendedDosTime(time.to(TimeUnit.MILLISECONDS));
         return this;
     }
 
@@ -204,9 +237,9 @@ class ZipEntry implements ZipConstants, Cloneable {
     public FileTime getLastModifiedTime() {
         if (mtime != null)
             return mtime;
-        if (time == -1)
+        if (xdostime == -1)
             return null;
-        return FileTime.from(time, TimeUnit.MILLISECONDS);
+        return FileTime.from(getTime(), TimeUnit.MILLISECONDS);
     }
 
     /**

src/share/classes/java/util/zip/ZipFile.java

 /*
- * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1995, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -46,7 +46,6 @@ import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
 import static java.util.zip.ZipConstants64.*;
-import static java.util.zip.ZipUtils.*;
 
 /**
  * This class is used to read entries from a zip file.
@@ -567,7 +566,7 @@ class ZipFile implements ZipConstants, Closeable {
                 e.name = zc.toString(bname, bname.length);
             }
         }
-        e.time = dosToJavaTime(getEntryTime(jzentry));
+        e.xdostime = getEntryTime(jzentry);
         e.crc = getEntryCrc(jzentry);
         e.size = getEntrySize(jzentry);
         e.csize = getEntryCSize(jzentry);

src/share/classes/java/util/zip/ZipInputStream.java

 /*
- * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -303,7 +303,7 @@ class ZipInputStream extends InflaterInputStream implements ZipConstants {
             throw new ZipException("encrypted ZIP entry not supported");
         }
         e.method = get16(tmpbuf, LOCHOW);
-        e.time = dosToJavaTime(get32(tmpbuf, LOCTIM));
+        e.xdostime = get32(tmpbuf, LOCTIM);
         if ((flag & 8) == 8) {
             /* "Data Descriptor" present */
             if (e.method != DEFLATED) {

src/share/classes/java/util/zip/ZipOutputStream.java

 /*
- * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -61,7 +61,6 @@ class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
     private static class XEntry {
         final ZipEntry entry;
         final long offset;
-        long dostime;    // last modification time in msdos format
         public XEntry(ZipEntry entry, long offset) {
             this.entry = entry;
             this.offset = offset;
@@ -192,7 +191,7 @@ class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
         if (current != null) {
             closeEntry();       // close previous entry
         }
-        if (e.time == -1) {
+        if (e.xdostime == -1) {
             // by default, do NOT use extended timestamps in extra
             // data, for now.
             e.setTime(System.currentTimeMillis());
@@ -389,18 +388,12 @@ class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
         boolean hasZip64 = false;
         int elen = getExtraLen(e.extra);
 
-        // keep a copy of dostime for writeCEN(), otherwise the tz
-        // sensitive local time entries in loc and cen might be
-        // different if the default tz get changed during writeLOC()
-        // and writeCEN()
-        xentry.dostime = javaToDosTime(e.time);
-
         writeInt(LOCSIG);               // LOC header signature
         if ((flag & 8) == 8) {
             writeShort(version(e));     // version needed to extract
             writeShort(flag);           // general purpose bit flag
             writeShort(e.method);       // compression method
-            writeInt(xentry.dostime);   // last modification time
+            writeInt(e.xdostime);       // last modification time
             // store size, uncompressed size, and crc-32 in data descriptor
             // immediately following compressed entry data
             writeInt(0);
@@ -415,7 +408,7 @@ class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
             }
             writeShort(flag);           // general purpose bit flag
             writeShort(e.method);       // compression method
-            writeInt(xentry.dostime);   // last modification time
+            writeInt(e.xdostime);       // last modification time
             writeInt(e.crc);            // crc-32
             if (hasZip64) {
                 writeInt(ZIP64_MAGICVAL);
@@ -522,9 +515,7 @@ class ZipOutputStream extends DeflaterOutputStream implements ZipConstants {
         }
         writeShort(flag);           // general purpose bit flag
         writeShort(e.method);       // compression method
-        // use the copy in xentry, which has been converted
-        // from e.time in writeLOC()
-        writeInt(xentry.dostime);   // last modification time
+        writeInt(e.xdostime);       // last modification time
         writeInt(e.crc);            // crc-32
         writeInt(csize);            // compressed size
         writeInt(size);             // uncompressed size

src/share/classes/java/util/zip/ZipUtils.java

 /*
- * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -29,9 +29,6 @@ import java.nio.file.attribute.FileTime;
 import java.util.Date;
 import java.util.concurrent.TimeUnit;
 
-import static java.util.zip.ZipConstants.*;
-import static java.util.zip.ZipConstants64.*;
-
 class ZipUtils {
 
     // used to adjust values between Windows and java epoch
@@ -69,7 +66,7 @@ class ZipUtils {
     /**
      * Converts DOS time to Java time (number of milliseconds since epoch).
      */
-    public static long dosToJavaTime(long dtime) {
+    private static long dosToJavaTime(long dtime) {
         @SuppressWarnings("deprecation") // Use of date constructor.
         Date d = new Date((int)(((dtime >> 25) & 0x7f) + 80),
                           (int)(((dtime >> 21) & 0x0f) - 1),
@@ -80,21 +77,50 @@ class ZipUtils {
         return d.getTime();
     }
 
+    /**
+     * Converts extended DOS time to Java time, where up to 1999 milliseconds
+     * might be encoded into the upper half of the returned long.
+     *
+     * @param xdostime the extended DOS time value
+     * @return milliseconds since epoch
+     */
+    public static long extendedDosToJavaTime(long xdostime) {
+        long time = dosToJavaTime(xdostime);
+        return time + (xdostime >> 32);
+    }
+
     /**
      * Converts Java time to DOS time.
      */
     @SuppressWarnings("deprecation") // Use of date methods
-    public static long javaToDosTime(long time) {
+    private static long javaToDosTime(long time) {
         Date d = new Date(time);
         int year = d.getYear() + 1900;
         if (year < 1980) {
-            return (1 << 21) | (1 << 16);
+            return ZipEntry.DOSTIME_BEFORE_1980;
         }
         return (year - 1980) << 25 | (d.getMonth() + 1) << 21 |
                d.getDate() << 16 | d.getHours() << 11 | d.getMinutes() << 5 |
                d.getSeconds() >> 1;
     }
 
+    /**
+     * Converts Java time to DOS time, encoding any milliseconds lost
+     * in the conversion into the upper half of the returned long.
+     *
+     * @param time milliseconds since epoch
+     * @return DOS time with 2s remainder encoded into upper half
+     */
+    public static long javaToExtendedDosTime(long time) {
+        if (time < 0) {
+            return ZipEntry.DOSTIME_BEFORE_1980;
+        }
+        long dostime = javaToDosTime(time);
+        return (dostime != ZipEntry.DOSTIME_BEFORE_1980)
+                ? dostime + ((time % 2000) << 32)
+                : ZipEntry.DOSTIME_BEFORE_1980;
+    }
+
     /**
      * Fetches unsigned 16-bit value from byte array at specified offset.
      * The bytes are assumed to be in Intel (little-endian) byte order.

test/java/util/zip/TestExtraTime.java

 /*
- * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,7 +23,7 @@
 
 /**
  * @test
- * @bug 4759491 6303183 7012868 8015666 8023713 8068790
+ * @bug 4759491 6303183 7012868 8015666 8023713 8068790 8074694
  * @summary Test ZOS and ZIS timestamp in extra field correctly
  */
 
@@ -71,6 +71,7 @@ public class TestExtraTime {
         }
 
         testNullHandling();
+        testTimeConversions();
     }
 
     static void test(FileTime mtime, FileTime atime, FileTime ctime,
@@ -178,4 +179,33 @@ public class TestExtraTime {
             // pass
         }
     }
+
+    // verify that setting and getting any time is possible as per the intent
+    // of 4759491
+    static void testTimeConversions() {
+        // Sample across the entire range
+        long step = Long.MAX_VALUE / 100L;
+        testTimeConversions(Long.MIN_VALUE, Long.MAX_VALUE - step, step);
+
+        // Samples through the near future
+        long currentTime = System.currentTimeMillis();
+        testTimeConversions(currentTime, currentTime + 1_000_000, 10_000);
+    }
+
+    static void testTimeConversions(long from, long to, long step) {
+        ZipEntry ze = new ZipEntry("TestExtraTime.java");
+        for (long time = from; time <= to; time += step) {
+            ze.setTime(time);
+            FileTime lastModifiedTime = ze.getLastModifiedTime();
+            if (lastModifiedTime.toMillis() != time) {
+                throw new RuntimeException("setTime should make getLastModifiedTime " +
+                        "return the specified instant: " + time +
+                        " got: " + lastModifiedTime.toMillis());
+            }
+            if (ze.getTime() != time) {
+                throw new RuntimeException("getTime after setTime, expected: " +
+                        time + " got: " + ze.getTime());
+            }
+        }
+    }
 }