michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.util;
michael@0: 
michael@0: import android.content.Context;
michael@0: import android.content.pm.PackageManager;
michael@0: import android.content.res.Configuration;
michael@0: import android.os.Build;
michael@0: import android.util.Log;
michael@0: import android.view.ViewConfiguration;
michael@0: 
michael@0: import java.io.FileInputStream;
michael@0: import java.io.FileNotFoundException;
michael@0: import java.io.IOException;
michael@0: import java.util.regex.Matcher;
michael@0: import java.util.regex.Pattern;
michael@0: 
michael@0: public final class HardwareUtils {
michael@0:     private static final String LOGTAG = "GeckoHardwareUtils";
michael@0: 
michael@0:     // Minimum memory threshold for a device to be considered
michael@0:     // a low memory platform (see isLowMemoryPlatform). This value
michael@0:     // has be in sync with Gecko's equivalent threshold (defined in
michael@0:     // xpcom/base/nsMemoryImpl.cpp) and should only be used in cases
michael@0:     // where we can't depend on Gecko to be up and running e.g. show/hide
michael@0:     // reading list capabilities in HomePager.
michael@0:     private static final int LOW_MEMORY_THRESHOLD_MB = 384;
michael@0: 
michael@0:     // Number of bytes of /proc/meminfo to read in one go.
michael@0:     private static final int MEMINFO_BUFFER_SIZE_BYTES = 256;
michael@0: 
michael@0:     private static volatile int sTotalRAM = -1;
michael@0: 
michael@0:     private static Context sContext;
michael@0: 
michael@0:     private static Boolean sIsLargeTablet;
michael@0:     private static Boolean sIsSmallTablet;
michael@0:     private static Boolean sIsTelevision;
michael@0:     private static Boolean sHasMenuButton;
michael@0: 
michael@0:     private HardwareUtils() {
michael@0:     }
michael@0: 
michael@0:     public static void init(Context context) {
michael@0:         if (sContext != null) {
michael@0:             Log.w(LOGTAG, "HardwareUtils.init called twice!");
michael@0:         }
michael@0:         sContext = context;
michael@0:     }
michael@0: 
michael@0:     public static boolean isTablet() {
michael@0:         return isLargeTablet() || isSmallTablet();
michael@0:     }
michael@0: 
michael@0:     public static boolean isLargeTablet() {
michael@0:         if (sIsLargeTablet == null) {
michael@0:             int screenLayout = sContext.getResources().getConfiguration().screenLayout;
michael@0:             sIsLargeTablet = (Build.VERSION.SDK_INT >= 11 &&
michael@0:                               ((screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_XLARGE));
michael@0:         }
michael@0:         return sIsLargeTablet;
michael@0:     }
michael@0: 
michael@0:     public static boolean isSmallTablet() {
michael@0:         if (sIsSmallTablet == null) {
michael@0:             int screenLayout = sContext.getResources().getConfiguration().screenLayout;
michael@0:             sIsSmallTablet = (Build.VERSION.SDK_INT >= 11 &&
michael@0:                               ((screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) == Configuration.SCREENLAYOUT_SIZE_LARGE));
michael@0:         }
michael@0:         return sIsSmallTablet;
michael@0:     }
michael@0: 
michael@0:     public static boolean isTelevision() {
michael@0:         if (sIsTelevision == null) {
michael@0:             sIsTelevision = sContext.getPackageManager().hasSystemFeature(PackageManager.FEATURE_TELEVISION);
michael@0:         }
michael@0:         return sIsTelevision;
michael@0:     }
michael@0: 
michael@0:     public static boolean hasMenuButton() {
michael@0:         if (sHasMenuButton == null) {
michael@0:             sHasMenuButton = Boolean.TRUE;
michael@0:             if (Build.VERSION.SDK_INT >= 11) {
michael@0:                 sHasMenuButton = Boolean.FALSE;
michael@0:             }
michael@0:             if (Build.VERSION.SDK_INT >= 14) {
michael@0:                 sHasMenuButton = ViewConfiguration.get(sContext).hasPermanentMenuKey();
michael@0:             }
michael@0:         }
michael@0:         return sHasMenuButton;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:     * Helper functions used to extract key/value data from /proc/meminfo
michael@0:     * Pulled from:
michael@0:     * http://androidxref.com/4.2_r1/xref/frameworks/base/core/java/com/android/internal/util/MemInfoReader.java
michael@0:     */
michael@0: 
michael@0:     private static boolean matchMemText(byte[] buffer, int index, int bufferLength, byte[] text) {
michael@0:         final int N = text.length;
michael@0:         if ((index + N) >= bufferLength) {
michael@0:             return false;
michael@0:         }
michael@0:         for (int i = 0; i < N; i++) {
michael@0:             if (buffer[index + i] != text[i]) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         return true;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Parses a line like:
michael@0:      *
michael@0:      *  MemTotal: 1605324 kB
michael@0:      *
michael@0:      * into 1605324.
michael@0:      *
michael@0:      * @return the first uninterrupted sequence of digits following the
michael@0:      *         specified index, parsed as an integer value in KB.
michael@0:      */
michael@0:     private static int extractMemValue(byte[] buffer, int offset, int length) {
michael@0:         if (offset >= length) {
michael@0:             return 0;
michael@0:         }
michael@0: 
michael@0:         while (offset < length && buffer[offset] != '\n') {
michael@0:             if (buffer[offset] >= '0' && buffer[offset] <= '9') {
michael@0:                 int start = offset++;
michael@0:                 while (offset < length &&
michael@0:                        buffer[offset] >= '0' &&
michael@0:                        buffer[offset] <= '9') {
michael@0:                     ++offset;
michael@0:                 }
michael@0:                 return Integer.parseInt(new String(buffer, start, offset - start), 10);
michael@0:             }
michael@0:             ++offset;
michael@0:         }
michael@0:         return 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Fetch the total memory of the device in MB by parsing /proc/meminfo.
michael@0:      *
michael@0:      * Of course, Android doesn't have a neat and tidy way to find total
michael@0:      * RAM, so we do it by parsing /proc/meminfo.
michael@0:      *
michael@0:      * @return 0 if a problem occurred, or memory size in MB.
michael@0:      */
michael@0:     public static int getMemSize() {
michael@0:         if (sTotalRAM >= 0) {
michael@0:             return sTotalRAM;
michael@0:         }
michael@0: 
michael@0:         // This is the string "MemTotal" that we're searching for in the buffer.
michael@0:         final byte[] MEMTOTAL = {'M', 'e', 'm', 'T', 'o', 't', 'a', 'l'};
michael@0:         try {
michael@0:             final byte[] buffer = new byte[MEMINFO_BUFFER_SIZE_BYTES];
michael@0:             final FileInputStream is = new FileInputStream("/proc/meminfo");
michael@0:             try {
michael@0:                 final int length = is.read(buffer);
michael@0: 
michael@0:                 for (int i = 0; i < length; i++) {
michael@0:                     if (matchMemText(buffer, i, length, MEMTOTAL)) {
michael@0:                         i += 8;
michael@0:                         sTotalRAM = extractMemValue(buffer, i, length) / 1024;
michael@0:                         Log.d(LOGTAG, "System memory: " + sTotalRAM + "MB.");
michael@0:                         return sTotalRAM;
michael@0:                     }
michael@0:                 }
michael@0:             } finally {
michael@0:                 is.close();
michael@0:             }
michael@0: 
michael@0:             Log.w(LOGTAG, "Did not find MemTotal line in /proc/meminfo.");
michael@0:             return sTotalRAM = 0;
michael@0:         } catch (FileNotFoundException f) {
michael@0:             return sTotalRAM = 0;
michael@0:         } catch (IOException e) {
michael@0:             return sTotalRAM = 0;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     public static boolean isLowMemoryPlatform() {
michael@0:         final int memSize = getMemSize();
michael@0: 
michael@0:         // Fallback to false if we fail to read meminfo
michael@0:         // for some reason.
michael@0:         if (memSize == 0) {
michael@0:             Log.w(LOGTAG, "Could not compute system memory. Falling back to isLowMemoryPlatform = false.");
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         return memSize < LOW_MEMORY_THRESHOLD_MB;
michael@0:     }
michael@0: }