1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.gallery3d.common;
18 
19 import android.content.Context;
20 import android.content.pm.PackageInfo;
21 import android.content.pm.PackageManager.NameNotFoundException;
22 import android.database.Cursor;
23 import android.os.Build;
24 import android.os.ParcelFileDescriptor;
25 import android.text.TextUtils;
26 import android.util.Log;
27 
28 import java.io.Closeable;
29 import java.io.IOException;
30 import java.io.InterruptedIOException;
31 
32 public class Utils {
33     private static final String TAG = "Utils";
34     private static final String DEBUG_TAG = "GalleryDebug";
35 
36     private static final long POLY64REV = 0x95AC9329AC4BC9B5L;
37     private static final long INITIALCRC = 0xFFFFFFFFFFFFFFFFL;
38 
39     private static long[] sCrcTable = new long[256];
40 
41     private static final boolean IS_DEBUG_BUILD =
42             Build.TYPE.equals("eng") || Build.TYPE.equals("userdebug");
43 
44     private static final String MASK_STRING = "********************************";
45 
46     // Throws AssertionError if the input is false.
assertTrue(boolean cond)47     public static void assertTrue(boolean cond) {
48         if (!cond) {
49             throw new AssertionError();
50         }
51     }
52 
53     // Throws AssertionError with the message. We had a method having the form
54     //   assertTrue(boolean cond, String message, Object ... args);
55     // However a call to that method will cause memory allocation even if the
56     // condition is false (due to autoboxing generated by "Object ... args"),
57     // so we don't use that anymore.
fail(String message, Object ... args)58     public static void fail(String message, Object ... args) {
59         throw new AssertionError(
60                 args.length == 0 ? message : String.format(message, args));
61     }
62 
63     // Throws NullPointerException if the input is null.
checkNotNull(T object)64     public static <T> T checkNotNull(T object) {
65         if (object == null) throw new NullPointerException();
66         return object;
67     }
68 
69     // Returns true if two input Object are both null or equal
70     // to each other.
equals(Object a, Object b)71     public static boolean equals(Object a, Object b) {
72         return (a == b) || (a == null ? false : a.equals(b));
73     }
74 
75     // Returns the next power of two.
76     // Returns the input if it is already power of 2.
77     // Throws IllegalArgumentException if the input is <= 0 or
78     // the answer overflows.
nextPowerOf2(int n)79     public static int nextPowerOf2(int n) {
80         if (n <= 0 || n > (1 << 30)) throw new IllegalArgumentException("n is invalid: " + n);
81         n -= 1;
82         n |= n >> 16;
83         n |= n >> 8;
84         n |= n >> 4;
85         n |= n >> 2;
86         n |= n >> 1;
87         return n + 1;
88     }
89 
90     // Returns the previous power of two.
91     // Returns the input if it is already power of 2.
92     // Throws IllegalArgumentException if the input is <= 0
prevPowerOf2(int n)93     public static int prevPowerOf2(int n) {
94         if (n <= 0) throw new IllegalArgumentException();
95         return Integer.highestOneBit(n);
96     }
97 
98     // Returns the input value x clamped to the range [min, max].
clamp(int x, int min, int max)99     public static int clamp(int x, int min, int max) {
100         if (x > max) return max;
101         if (x < min) return min;
102         return x;
103     }
104 
105     // Returns the input value x clamped to the range [min, max].
clamp(float x, float min, float max)106     public static float clamp(float x, float min, float max) {
107         if (x > max) return max;
108         if (x < min) return min;
109         return x;
110     }
111 
112     // Returns the input value x clamped to the range [min, max].
clamp(long x, long min, long max)113     public static long clamp(long x, long min, long max) {
114         if (x > max) return max;
115         if (x < min) return min;
116         return x;
117     }
118 
isOpaque(int color)119     public static boolean isOpaque(int color) {
120         return color >>> 24 == 0xFF;
121     }
122 
swap(int[] array, int i, int j)123     public static void swap(int[] array, int i, int j) {
124         int temp = array[i];
125         array[i] = array[j];
126         array[j] = temp;
127     }
128 
129     /**
130      * A function thats returns a 64-bit crc for string
131      *
132      * @param in input string
133      * @return a 64-bit crc value
134      */
crc64Long(String in)135     public static final long crc64Long(String in) {
136         if (in == null || in.length() == 0) {
137             return 0;
138         }
139         return crc64Long(getBytes(in));
140     }
141 
142     static {
143         // http://bioinf.cs.ucl.ac.uk/downloads/crc64/crc64.c
144         long part;
145         for (int i = 0; i < 256; i++) {
146             part = i;
147             for (int j = 0; j < 8; j++) {
148                 long x = ((int) part & 1) != 0 ? POLY64REV : 0;
149                 part = (part >> 1) ^ x;
150             }
151             sCrcTable[i] = part;
152         }
153     }
154 
crc64Long(byte[] buffer)155     public static final long crc64Long(byte[] buffer) {
156         long crc = INITIALCRC;
157         for (int k = 0, n = buffer.length; k < n; ++k) {
158             crc = sCrcTable[(((int) crc) ^ buffer[k]) & 0xff] ^ (crc >> 8);
159         }
160         return crc;
161     }
162 
getBytes(String in)163     public static byte[] getBytes(String in) {
164         byte[] result = new byte[in.length() * 2];
165         int output = 0;
166         for (char ch : in.toCharArray()) {
167             result[output++] = (byte) (ch & 0xFF);
168             result[output++] = (byte) (ch >> 8);
169         }
170         return result;
171     }
172 
closeSilently(Closeable c)173     public static void closeSilently(Closeable c) {
174         if (c == null) return;
175         try {
176             c.close();
177         } catch (IOException t) {
178             Log.w(TAG, "close fail ", t);
179         }
180     }
181 
compare(long a, long b)182     public static int compare(long a, long b) {
183         return a < b ? -1 : a == b ? 0 : 1;
184     }
185 
ceilLog2(float value)186     public static int ceilLog2(float value) {
187         int i;
188         for (i = 0; i < 31; i++) {
189             if ((1 << i) >= value) break;
190         }
191         return i;
192     }
193 
floorLog2(float value)194     public static int floorLog2(float value) {
195         int i;
196         for (i = 0; i < 31; i++) {
197             if ((1 << i) > value) break;
198         }
199         return i - 1;
200     }
201 
closeSilently(ParcelFileDescriptor fd)202     public static void closeSilently(ParcelFileDescriptor fd) {
203         try {
204             if (fd != null) fd.close();
205         } catch (Throwable t) {
206             Log.w(TAG, "fail to close", t);
207         }
208     }
209 
closeSilently(Cursor cursor)210     public static void closeSilently(Cursor cursor) {
211         try {
212             if (cursor != null) cursor.close();
213         } catch (Throwable t) {
214             Log.w(TAG, "fail to close", t);
215         }
216     }
217 
interpolateAngle( float source, float target, float progress)218     public static float interpolateAngle(
219             float source, float target, float progress) {
220         // interpolate the angle from source to target
221         // We make the difference in the range of [-179, 180], this is the
222         // shortest path to change source to target.
223         float diff = target - source;
224         if (diff < 0) diff += 360f;
225         if (diff > 180) diff -= 360f;
226 
227         float result = source + diff * progress;
228         return result < 0 ? result + 360f : result;
229     }
230 
interpolateScale( float source, float target, float progress)231     public static float interpolateScale(
232             float source, float target, float progress) {
233         return source + progress * (target - source);
234     }
235 
ensureNotNull(String value)236     public static String ensureNotNull(String value) {
237         return value == null ? "" : value;
238     }
239 
parseFloatSafely(String content, float defaultValue)240     public static float parseFloatSafely(String content, float defaultValue) {
241         if (content == null) return defaultValue;
242         try {
243             return Float.parseFloat(content);
244         } catch (NumberFormatException e) {
245             return defaultValue;
246         }
247     }
248 
parseIntSafely(String content, int defaultValue)249     public static int parseIntSafely(String content, int defaultValue) {
250         if (content == null) return defaultValue;
251         try {
252             return Integer.parseInt(content);
253         } catch (NumberFormatException e) {
254             return defaultValue;
255         }
256     }
257 
isNullOrEmpty(String exifMake)258     public static boolean isNullOrEmpty(String exifMake) {
259         return TextUtils.isEmpty(exifMake);
260     }
261 
waitWithoutInterrupt(Object object)262     public static void waitWithoutInterrupt(Object object) {
263         try {
264             object.wait();
265         } catch (InterruptedException e) {
266             Log.w(TAG, "unexpected interrupt: " + object);
267         }
268     }
269 
handleInterrruptedException(Throwable e)270     public static boolean handleInterrruptedException(Throwable e) {
271         // A helper to deal with the interrupt exception
272         // If an interrupt detected, we will setup the bit again.
273         if (e instanceof InterruptedIOException
274                 || e instanceof InterruptedException) {
275             Thread.currentThread().interrupt();
276             return true;
277         }
278         return false;
279     }
280 
281     /**
282      * @return String with special XML characters escaped.
283      */
escapeXml(String s)284     public static String escapeXml(String s) {
285         StringBuilder sb = new StringBuilder();
286         for (int i = 0, len = s.length(); i < len; ++i) {
287             char c = s.charAt(i);
288             switch (c) {
289                 case '<':  sb.append("&lt;"); break;
290                 case '>':  sb.append("&gt;"); break;
291                 case '\"': sb.append("&quot;"); break;
292                 case '\'': sb.append("&#039;"); break;
293                 case '&':  sb.append("&amp;"); break;
294                 default: sb.append(c);
295             }
296         }
297         return sb.toString();
298     }
299 
getUserAgent(Context context)300     public static String getUserAgent(Context context) {
301         PackageInfo packageInfo;
302         try {
303             packageInfo = context.getPackageManager().getPackageInfo(context.getPackageName(), 0);
304         } catch (NameNotFoundException e) {
305             throw new IllegalStateException("getPackageInfo failed");
306         }
307         return String.format("%s/%s; %s/%s/%s/%s; %s/%s/%s",
308                 packageInfo.packageName,
309                 packageInfo.versionName,
310                 Build.BRAND,
311                 Build.DEVICE,
312                 Build.MODEL,
313                 Build.ID,
314                 Build.VERSION.SDK_INT,
315                 Build.VERSION.RELEASE,
316                 Build.VERSION.INCREMENTAL);
317     }
318 
copyOf(String[] source, int newSize)319     public static String[] copyOf(String[] source, int newSize) {
320         String[] result = new String[newSize];
321         newSize = Math.min(source.length, newSize);
322         System.arraycopy(source, 0, result, 0, newSize);
323         return result;
324     }
325 
326     // Mask information for debugging only. It returns <code>info.toString()</code> directly
327     // for debugging build (i.e., 'eng' and 'userdebug') and returns a mask ("****")
328     // in release build to protect the information (e.g. for privacy issue).
maskDebugInfo(Object info)329     public static String maskDebugInfo(Object info) {
330         if (info == null) return null;
331         String s = info.toString();
332         int length = Math.min(s.length(), MASK_STRING.length());
333         return IS_DEBUG_BUILD ? s : MASK_STRING.substring(0, length);
334     }
335 
336     // This method should be ONLY used for debugging.
debug(String message, Object ... args)337     public static void debug(String message, Object ... args) {
338         Log.v(DEBUG_TAG, String.format(message, args));
339     }
340 }
341