1 files changed, 114 insertions, 48 deletions
diff --git a/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java b/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java
index 76a230f82..f4ba0bcdc 100644
--- a/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java
+++ b/java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java
@@ -19,8 +19,11 @@ package com.android.inputmethod.latin;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.AssetFileDescriptor;
+import android.content.res.Resources;
+import android.database.Cursor;
 import android.net.Uri;
 import android.text.TextUtils;
+import android.util.Log;
 
 import java.io.File;
 import java.io.FileInputStream;
@@ -28,7 +31,8 @@ import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
 
@@ -37,47 +41,111 @@ import java.util.Locale;
  * file from the dictionary provider
  */
 public class BinaryDictionaryFileDumper {
+    private static final String TAG = BinaryDictionaryFileDumper.class.getSimpleName();
+
     /**
      * The size of the temporary buffer to copy files.
      */
     static final int FILE_READ_BUFFER_SIZE = 1024;
 
+    private static final String DICTIONARY_PROJECTION[] = { "id" };
+
     // Prevents this class to be accidentally instantiated.
     private BinaryDictionaryFileDumper() {
     }
 
     /**
-     * Generates a file name that matches the locale passed as an argument.
-     * The file name is basically the result of the .toString() method, except we replace
-     * any @File.separator with an underscore to avoid generating a file name that may not
-     * be created.
+     * Escapes a string for any characters that may be suspicious for a file or directory name.
+     *
+     * Concretely this does a sort of URL-encoding except it will encode everything that's not
+     * alphanumeric or underscore. (true URL-encoding leaves alone characters like '*', which
+     * we cannot allow here)
+     */
+    // TODO: create a unit test for this method
+    private static String replaceFileNameDangerousCharacters(String name) {
+        // This assumes '%' is fully available as a non-separator, normal
+        // character in a file name. This is probably true for all file systems.
+        final StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < name.length(); ++i) {
+            final int codePoint = name.codePointAt(i);
+            if (Character.isLetterOrDigit(codePoint) || '_' == codePoint) {
+                sb.appendCodePoint(codePoint);
+            } else {
+                sb.append('%');
+                sb.append(Integer.toHexString(codePoint));
+            }
+        }
+        return sb.toString();
+    }
+
+    /**
+     * Find out the cache directory associated with a specific locale.
+     */
+    private static String getCacheDirectoryForLocale(Locale locale, Context context) {
+        final String relativeDirectoryName = replaceFileNameDangerousCharacters(locale.toString());
+        final String absoluteDirectoryName = context.getFilesDir() + File.separator
+                + relativeDirectoryName;
+        final File directory = new File(absoluteDirectoryName);
+        if (!directory.exists()) {
+            if (!directory.mkdirs()) {
+                Log.e(TAG, "Could not create the directory for locale" + locale);
+            }
+        }
+        return absoluteDirectoryName;
+    }
+
+    /**
+     * Generates a file name for the id and locale passed as an argument.
+     *
+     * In the current implementation the file name returned will always be unique for
+     * any id/locale pair, but please do not expect that the id can be the same for
+     * different dictionaries with different locales. An id should be unique for any
+     * dictionary.
+     * The file name is pretty much an URL-encoded version of the id inside a directory
+     * named like the locale, except it will also escape characters that look dangerous
+     * to some file systems.
+     * @param id the id of the dictionary for which to get a file name
      * @param locale the locale for which to get the file name
      * @param context the context to use for getting the directory
      * @return the name of the file to be created
      */
-    private static String getCacheFileNameForLocale(Locale locale, Context context) {
-        // The following assumes two things :
-        // 1. That File.separator is not the same character as "_"
-        //    I don't think any android system will ever use "_" as a path separator
-        // 2. That no two locales differ by only a File.separator versus a "_"
-        //    Since "_" can't be part of locale components this should be safe.
-        // Examples:
-        // en -> en
-        // en_US_POSIX -> en_US_POSIX
-        // en__foo/bar -> en__foo_bar
-        final String[] separator = { File.separator };
-        final String[] empty = { "_" };
-        final CharSequence basename = TextUtils.replace(locale.toString(), separator, empty);
-        return context.getFilesDir() + File.separator + basename;
+    private static String getCacheFileName(String id, Locale locale, Context context) {
+        final String fileName = replaceFileNameDangerousCharacters(id);
+        return getCacheDirectoryForLocale(locale, context) + File.separator + fileName;
     }
 
     /**
-     * Return for a given locale the provider URI to query to get the dictionary.
+     * Return for a given locale or dictionary id the provider URI to get the dictionary.
      */
-    public static Uri getProviderUri(Locale locale) {
+    private static Uri getProviderUri(String path) {
         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
                 .authority(BinaryDictionary.DICTIONARY_PACK_AUTHORITY).appendPath(
-                        locale.toString()).build();
+                        path).build();
+    }
+
+    /**
+     * Queries a content provider for the list of dictionaries for a specific locale
+     * available to copy into Latin IME.
+     */
+    private static List<String> getDictIdList(final Locale locale, final Context context) {
+        final ContentResolver resolver = context.getContentResolver();
+        final Uri dictionaryPackUri = getProviderUri(locale.toString());
+
+        final Cursor c = resolver.query(dictionaryPackUri, DICTIONARY_PROJECTION, null, null, null);
+        if (null == c) return Collections.<String>emptyList();
+        if (c.getCount() <= 0 || !c.moveToFirst()) {
+            c.close();
+            return Collections.<String>emptyList();
+        }
+
+        final List<String> list = new ArrayList<String>();
+        do {
+            final String id = c.getString(0);
+            if (TextUtils.isEmpty(id)) continue;
+            list.add(id);
+        } while (c.moveToNext());
+        c.close();
+        return list;
     }
 
     /**
@@ -94,31 +162,26 @@ public class BinaryDictionaryFileDumper {
      * @throw FileNotFoundException if the provider returns non-existent data.
      * @throw IOException if the provider-returned data could not be read.
      */
-    public static List<AssetFileAddress> getDictSetFromContentProvider(Locale locale,
-            Context context) throws FileNotFoundException, IOException {
-        // TODO: check whether the dictionary is the same or not and if it is, return the cached
-        // file.
-        // TODO: This should be able to read a number of files from the dictionary pack, copy
-        // them all and return them.
+    public static List<AssetFileAddress> getDictSetFromContentProvider(final Locale locale,
+            final Context context) throws FileNotFoundException, IOException {
         final ContentResolver resolver = context.getContentResolver();
-        final Uri dictionaryPackUri = getProviderUri(locale);
-        final AssetFileDescriptor afd = resolver.openAssetFileDescriptor(dictionaryPackUri, "r");
-        if (null == afd) return null;
-        final String fileName =
-                copyFileTo(afd.createInputStream(), getCacheFileNameForLocale(locale, context));
-        return Arrays.asList(AssetFileAddress.makeFromFileName(fileName));
-    }
-
-    /**
-     * Accepts a file as dictionary data for some locale and returns the name of a file.
-     *
-     * This will make the data in the input file the cached dictionary for this locale, overwriting
-     * any previous cached data.
-     */
-    public static String getDictionaryFileFromFile(String fileName, Locale locale,
-            Context context) throws FileNotFoundException, IOException {
-        return copyFileTo(new FileInputStream(fileName), getCacheFileNameForLocale(locale,
-                context));
+        final List<String> idList = getDictIdList(locale, context);
+        final List<AssetFileAddress> fileAddressList = new ArrayList<AssetFileAddress>();
+        for (String id : idList) {
+            final Uri wordListUri = getProviderUri(id);
+            final AssetFileDescriptor afd =
+                    resolver.openAssetFileDescriptor(wordListUri, "r");
+            if (null == afd) continue;
+            final String fileName = copyFileTo(afd.createInputStream(),
+                    getCacheFileName(id, locale, context));
+            afd.close();
+            if (0 >= resolver.delete(wordListUri, null, null)) {
+                // I'd rather not print the word list ID to the log here out of security concerns
+                Log.e(TAG, "Could not have the dictionary pack delete a word list");
+            }
+            fileAddressList.add(AssetFileAddress.makeFromFileName(fileName));
+        }
+        return fileAddressList;
     }
 
     /**
@@ -129,8 +192,11 @@ public class BinaryDictionaryFileDumper {
      */
     public static String getDictionaryFileFromResource(int resource, Locale locale,
             Context context) throws FileNotFoundException, IOException {
-        return copyFileTo(context.getResources().openRawResource(resource),
-                getCacheFileNameForLocale(locale, context));
+        final Resources res = context.getResources();
+        final Locale savedLocale = Utils.setSystemLocale(res, locale);
+        final InputStream stream = res.openRawResource(resource);
+        Utils.setSystemLocale(res, savedLocale);
+        return copyFileTo(stream, getCacheFileName(Integer.toString(resource), locale, context));
     }
 
     /**