Allow zim::Archive to be created with a set of File descriptor.

lib/build.gradle

@@ -354,7 +354,8 @@ String getLibzimFiles() {
         "${projectDir}/src/main/java/org/kiwix/libzim/SuggestionSearcher.java " +
         "${projectDir}/src/main/java/org/kiwix/libzim/SuggestionSearch.java " +
         "${projectDir}/src/main/java/org/kiwix/libzim/ZimFileFormatException.java " +
-        "${projectDir}/src/main/java/org/kiwix/libzim/EntryNotFoundException.java"
+        "${projectDir}/src/main/java/org/kiwix/libzim/EntryNotFoundException.java " +
+        "${projectDir}/src/main/java/org/kiwix/libzim/FdInput.java"
 }
 
 task buildLinuxBinding(type: Exec) {

lib/src/main/cpp/libzim/archive.cpp

@@ -62,6 +62,23 @@ int jni2fd(const jobject& fdObj, JNIEnv* env)
   return env->GetIntField(fdObj, field_fd);
 }
 
+zim::FdInput jni2fdInput(const jobject& fdInputObj, JNIEnv* env)
+{
+  jclass class_fdesc = env->FindClass("org/kiwix/libzim/FdInput");
+
+  jfieldID field_id = env->GetFieldID(class_fdesc, "fd", "Ljava/io/FileDescriptor;");
+  jobject fdObj = env->GetObjectField(fdInputObj, field_id);
+  int fd = jni2fd(fdObj, env);
+
+  field_id = env->GetFieldID(class_fdesc, "offset", "J");
+  long offset = env->GetLongField(fdInputObj, field_id);
+
+  field_id = env->GetFieldID(class_fdesc, "size", "J");
+  long size = env->GetLongField(fdInputObj, field_id);
+
+  return zim::FdInput(fd, offset, size);
+}
+
 } // unnamed namespace
 
 JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveByFD(
@@ -71,13 +88,8 @@ JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveByFD(
   int fd = jni2fd(fdObj, env);
 
   LOG("Attempting to create reader with fd: %d", fd);
-  try {
-    auto archive = std::make_shared<zim::Archive>(fd);
-    SET_PTR(archive);
-  } catch (std::exception& e) {
-    LOG("Error opening ZIM file");
-       LOG("%s", e.what());
-  }
+  auto archive = std::make_shared<zim::Archive>(fd);
+  SET_PTR(archive);
 #else
   jclass exception = env->FindClass("java/lang/UnsupportedOperationException");
   env->ThrowNew(exception, "org.kiwix.libzim.Archive.setNativeArchiveByFD() is not supported under Windows");
@@ -91,13 +103,46 @@ JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveEmbedded(
   int fd = jni2fd(fdObj, env);
 
   LOG("Attempting to create reader with fd: %d", fd);
-  try {
-    auto archive = std::make_shared<zim::Archive>(fd, offset, size);
-    SET_PTR(archive);
-  } catch (std::exception& e) {
-    LOG("Error opening ZIM file");
-       LOG("%s", e.what());
+  auto archive = std::make_shared<zim::Archive>(fd, offset, size);
+  SET_PTR(archive);
+#else
+  jclass exception = env->FindClass("java/lang/UnsupportedOperationException");
+  env->ThrowNew(exception, "org.kiwix.libzim.Archive.setNativeArchiveEmbedded() is not supported under Windows");
+#endif
+} CATCH_EXCEPTION()
+
+JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveEmbeddedFd(
+    JNIEnv* env, jobject thisObj, jobject fdObj) try
+{
+#ifndef _WIN32
+  auto fdInput = jni2fdInput(fdObj, env);
+
+  auto archive = std::make_shared<zim::Archive>(fdInput);
+  SET_PTR(archive);
+#else
+  jclass exception = env->FindClass("java/lang/UnsupportedOperationException");
+  env->ThrowNew(exception, "org.kiwix.libzim.Archive.setNativeArchiveEmbedded() is not supported under Windows");
+#endif
+} CATCH_EXCEPTION()
+
+
+JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveEmbeddedFds(
+    JNIEnv* env, jobject thisObj, jobjectArray fdsObj) try
+{
+#ifndef _WIN32
+
+  jsize length = env->GetArrayLength(fdsObj);
+  std::vector<zim::FdInput> v;
+
+  int i;
+  for(i = 0; i<length; i++) {
+    jobject fdObj = env->GetObjectArrayElement(fdsObj, i);
+    auto fdInput = jni2fdInput(fdObj, env);
+    v.push_back(fdInput);
   }
+
+  auto archive = std::make_shared<zim::Archive>(v);
+  SET_PTR(archive);
 #else
   jclass exception = env->FindClass("java/lang/UnsupportedOperationException");
   env->ThrowNew(exception, "org.kiwix.libzim.Archive.setNativeArchiveEmbedded() is not supported under Windows");

lib/src/main/java/org/kiwix/libzim/Archive.java

@@ -23,6 +23,7 @@
 import org.kiwix.libzim.Entry;
 import org.kiwix.libzim.Item;
 import org.kiwix.libzim.EntryIterator;
+import org.kiwix.libzim.FdInput;
 import java.io.FileDescriptor;
 
 public class Archive
@@ -44,6 +45,18 @@ public Archive(FileDescriptor fd, long offset, long size)
     setNativeArchiveEmbedded(fd, offset, size);
   }
 
+  public Archive(FdInput fd)
+  throws ZimFileFormatException
+  {
+    setNativeArchiveEmbeddedFd(fd);
+  }
+
+  public Archive(FdInput[] fds)
+  throws ZimFileFormatException
+  {
+    setNativeArchiveEmbeddedFds(fds);
+  }
+
   public native String getFilename();
   public native long getFilesize();
   public native int getAllEntryCount();
@@ -94,6 +107,8 @@ public Archive(FileDescriptor fd, long offset, long size)
   private native void setNativeArchive(String filename);
   private native void setNativeArchiveByFD(FileDescriptor fd);
   private native void setNativeArchiveEmbedded(FileDescriptor fd, long offset, long size);
+  private native void setNativeArchiveEmbeddedFd(FdInput fd);
+  private native void setNativeArchiveEmbeddedFds(FdInput[] fds);
 
   @Override
   protected void finalize() { dispose(); }

lib/src/main/java/org/kiwix/libzim/FdInput.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2017 Matthieu Gautier <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU  General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ */
+
+package org.kiwix.libzim;
+
+import java.io.FileDescriptor;
+
+public class FdInput
+{
+  public FileDescriptor fd;
+  public long offset;
+  public long size;
+
+  public FdInput(FileDescriptor fd_, long offset_, long size_) {
+    fd = fd_;
+    offset = offset_;
+    size = size_;
+  }
+}

lib/src/test/org/kiwix/test/libzim/TestArchive.java

@@ -47,6 +47,18 @@ public TestArchive(FileDescriptor fd, long offset, long size)
     inner = new Archive(fd, offset, size);
   }
 
+  public TestArchive(FdInput fd)
+          throws ZimFileFormatException
+  {
+    inner = new Archive(fd);
+  }
+
+  public TestArchive(FdInput[] fds)
+          throws ZimFileFormatException
+  {
+    inner = new Archive(fds);
+  }
+
   public String getFilename() { return inner.getFilename(); }
   public long getFilesize() { return inner.getFilesize(); }
   public int getAllEntryCount() { return inner.getAllEntryCount(); }

lib/src/test/test.java

@@ -83,11 +83,9 @@ private void testArchive(TestArchive archive)
         assertTrue(Arrays.equals(faviconData, readData));
 
         // Checking all metadata
-        assertFalse(archive.isMultiPart());
         assertTrue(archive.hasNewNamespaceScheme());
         assertTrue(archive.hasChecksum());
         assertEquals("4a2709fddbee8c27db708c20b4952a06", archive.getChecksum());
-        assertTrue(archive.hasTitleIndex());
         assertTrue(archive.hasFulltextIndex());
         assertTrue(archive.hasMainEntry());
         long[] illuSizes = {48};
@@ -221,6 +219,8 @@ public void testArchiveDirect()
         {
             TestArchive archive = new TestArchive("small.zim");
             testArchive(archive);
+            assertFalse(archive.isMultiPart());
+            assertTrue(archive.hasTitleIndex());
             assertTrue(archive.check());
             assertEquals("small.zim", archive.getFilename());
         }
@@ -261,6 +261,26 @@ public void testArchiveByFd()
             FileInputStream fis = new FileInputStream("small.zim");
             TestArchive archive = new TestArchive(fis.getFD());
             testArchive(archive);
+            assertFalse(archive.isMultiPart());
+            assertTrue(archive.hasTitleIndex());
+            assertTrue(archive.check());
+            assertEquals("", archive.getFilename());
+        }
+        System.gc();
+        System.runFinalization();
+    }
+
+    @Test
+    public void testArchiveByFdInput()
+            throws JNIKiwixException, IOException, ZimFileFormatException, EntryNotFoundException {
+        {
+            File plainArchive = new File("small.zim");
+            FileInputStream fis = new FileInputStream("small.zim");
+            FdInput fd = new FdInput(fis.getFD(), 0, plainArchive.length());
+            TestArchive archive = new TestArchive(fd);
+            testArchive(archive);
+            assertFalse(archive.isMultiPart());
+            assertTrue(archive.hasTitleIndex());
             assertTrue(archive.check());
             assertEquals("", archive.getFilename());
         }
@@ -278,6 +298,56 @@ public void testArchiveWithAnEmbeddedArchive()
             // This fails. See https://github.com/openzim/libzim/issues/812
             //assertTrue(archive.check());
             testArchive(archive);
+            assertFalse(archive.isMultiPart());
+            assertTrue(archive.hasTitleIndex());
+            assertEquals("", archive.getFilename());
+        }
+        System.gc();
+        System.runFinalization();
+    }
+
+    @Test
+    public void testArchiveWithAnEmbeddedArchiveFdInputNaive()
+            throws JNIKiwixException, IOException, ZimFileFormatException, EntryNotFoundException {
+        {
+            File plainArchive = new File("small.zim");
+            FileInputStream fis = new FileInputStream("small.zim.embedded");
+            FdInput fd1 = new FdInput(fis.getFD(), 8, plainArchive.length() / 2);
+            FdInput fd2 = new FdInput(fis.getFD(), fd1.offset + fd1.size, plainArchive.length() - fd1.size);
+
+            FdInput fds[] = {fd1, fd2};
+
+            TestArchive archive = new TestArchive(fds);
+            // This fails. See https://github.com/openzim/libzim/issues/812
+            //assertTrue(archive.check());
+            testArchive(archive);
+            assertTrue(archive.isMultiPart());
+            //Naive split cut the title index in the middle. libzim cannot read it.
+            assertFalse(archive.hasTitleIndex());
+            assertEquals("", archive.getFilename());
+        }
+        System.gc();
+        System.runFinalization();
+    }
+
+    @Test
+    public void testArchiveWithAnEmbeddedArchiveFdInput()
+            throws JNIKiwixException, IOException, ZimFileFormatException, EntryNotFoundException {
+        {
+            File plainArchive = new File("small.zim");
+            FileInputStream fis = new FileInputStream("small.zim.embedded");
+            FdInput fd1 = new FdInput(fis.getFD(), 8, plainArchive.length() / 10);
+            FdInput fd2 = new FdInput(fis.getFD(), fd1.offset + fd1.size, plainArchive.length() - fd1.size);
+
+            FdInput fds[] = {fd1, fd2};
+
+            TestArchive archive = new TestArchive(fds);
+            // This fails. See https://github.com/openzim/libzim/issues/812
+            //assertTrue(archive.check());
+            testArchive(archive);
+            assertTrue(archive.isMultiPart());
+            //If we don't cut in the middle of xapian db, we can read it.
+            assertTrue(archive.hasTitleIndex());
             assertEquals("", archive.getFilename());
         }
         System.gc();