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 */
16package eu.siacs.conversations.utils;
17
18import android.content.Context;
19import android.database.Cursor;
20import android.net.Uri;
21import android.provider.OpenableColumns;
22import android.util.Log;
23import com.google.common.base.Strings;
24import com.google.common.collect.ImmutableList;
25import eu.siacs.conversations.Config;
26import eu.siacs.conversations.entities.Transferable;
27import eu.siacs.conversations.worker.ExportBackupWorker;
28import java.io.File;
29import java.io.FileInputStream;
30import java.io.IOException;
31import java.io.InputStream;
32import java.util.Arrays;
33import java.util.Collection;
34import java.util.HashMap;
35import java.util.List;
36import java.util.Map;
37import java.util.Properties;
38
39/**
40 * Utilities for dealing with MIME types. Used to implement java.net.URLConnection and
41 * android.webkit.MimeTypeMap.
42 */
43public final class MimeUtils {
44
45 public static final List<String> AMBIGUOUS_CONTAINER_FORMATS =
46 ImmutableList.of(
47 "application/ogg",
48 "video/3gpp", // .3gp files can contain audio, video or both
49 "video/3gpp2");
50
51 public static final List<String> WORD_DOCUMENT_MIMES =
52 Arrays.asList(
53 "application/vnd.oasis.opendocument.text",
54 "application/msword",
55 "application/vnd.openxmlformats-officedocument.wordprocessingml.document");
56
57 private static final Map<String, String> mimeTypeToExtensionMap = new HashMap<>();
58 private static final Map<String, String> extensionToMimeTypeMap = new HashMap<>();
59
60 static {
61 // The following table is based on /etc/mime.types data minus
62 // chemical/* MIME types and MIME types that don't map to any
63 // file extensions. We also exclude top-level domain names to
64 // deal with cases like:
65 //
66 // mail.google.com/a/google.com
67 //
68 // and "active" MIME types (due to potential security issues).
69 // Note that this list is _not_ in alphabetical order and must not be sorted.
70 // The "most popular" extension must come first, so that it's the one returned
71 // by guessExtensionFromMimeType.
72 add("application/andrew-inset", "ez");
73 add("application/dsptype", "tsp");
74 add("application/json", "json");
75 add("application/epub+zip", "epub");
76 add("application/gpx+xml", "gpx");
77 add("application/hta", "hta");
78 add("application/mac-binhex40", "hqx");
79 add("application/mathematica", "nb");
80 add("application/msaccess", "mdb");
81 add("application/oda", "oda");
82 add("application/ogg", "ogg");
83 add("application/pdf", "pdf");
84 add("application/pgp-keys", "key");
85 add("application/pgp-signature", "pgp");
86 add("application/pics-rules", "prf");
87 add("application/pkix-cert", "cer");
88 add("application/rar", "rar");
89 add("application/rdf+xml", "rdf");
90 add("application/rss+xml", "rss");
91 add("application/zip", "zip");
92 add("application/vnd.amazon.mobi8-ebook", "azw3");
93 add("application/vnd.amazon.mobi8-ebook", "azw");
94 add("application/vnd.amazon.mobi8-ebook", "kfx");
95 add("application/vnd.android.package-archive", "apk");
96 add("application/vnd.cinderella", "cdy");
97 add(ExportBackupWorker.MIME_TYPE, "ceb");
98 add("application/vnd.ms-pki.stl", "stl");
99 add("application/vnd.oasis.opendocument.database", "odb");
100 add("application/vnd.oasis.opendocument.formula", "odf");
101 add("application/vnd.oasis.opendocument.graphics", "odg");
102 add("application/vnd.oasis.opendocument.graphics-template", "otg");
103 add("application/vnd.oasis.opendocument.image", "odi");
104 add("application/vnd.oasis.opendocument.spreadsheet", "ods");
105 add("application/vnd.oasis.opendocument.spreadsheet-template", "ots");
106 add("application/vnd.oasis.opendocument.text", "odt");
107 add("application/vnd.oasis.opendocument.text-master", "odm");
108 add("application/vnd.oasis.opendocument.text-template", "ott");
109 add("application/vnd.oasis.opendocument.text-web", "oth");
110 add("application/vnd.oasis.opendocument.presentation", "odp");
111 add("application/vnd.google-earth.kml+xml", "kml");
112 add("application/vnd.google-earth.kmz", "kmz");
113 add("application/msword", "doc");
114 add("application/msword", "dot");
115 add("application/vnd.openxmlformats-officedocument.wordprocessingml.document", "docx");
116 add("application/vnd.openxmlformats-officedocument.wordprocessingml.template", "dotx");
117 add("application/vnd.ms-excel", "xls");
118 add("application/vnd.ms-excel", "xlt");
119 add("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "xlsx");
120 add("application/vnd.openxmlformats-officedocument.spreadsheetml.template", "xltx");
121 add("application/vnd.ms-powerpoint", "ppt");
122 add("application/vnd.ms-powerpoint", "pot");
123 add("application/vnd.ms-powerpoint", "pps");
124 add("application/vnd.openxmlformats-officedocument.presentationml.presentation", "pptx");
125 add("application/vnd.openxmlformats-officedocument.presentationml.template", "potx");
126 add("application/vnd.openxmlformats-officedocument.presentationml.slideshow", "ppsx");
127 add("application/vnd.rim.cod", "cod");
128 add("application/vnd.smaf", "mmf");
129 add("application/vnd.stardivision.calc", "sdc");
130 add("application/vnd.stardivision.draw", "sda");
131 add("application/vnd.stardivision.impress", "sdd");
132 add("application/vnd.stardivision.impress", "sdp");
133 add("application/vnd.stardivision.math", "smf");
134 add("application/vnd.stardivision.writer", "sdw");
135 add("application/vnd.stardivision.writer", "vor");
136 add("application/vnd.stardivision.writer-global", "sgl");
137 add("application/vnd.sun.xml.calc", "sxc");
138 add("application/vnd.sun.xml.calc.template", "stc");
139 add("application/vnd.sun.xml.draw", "sxd");
140 add("application/vnd.sun.xml.draw.template", "std");
141 add("application/vnd.sun.xml.impress", "sxi");
142 add("application/vnd.sun.xml.impress.template", "sti");
143 add("application/vnd.sun.xml.math", "sxm");
144 add("application/vnd.sun.xml.writer", "sxw");
145 add("application/vnd.sun.xml.writer.global", "sxg");
146 add("application/vnd.sun.xml.writer.template", "stw");
147 add("application/vnd.visio", "vsd");
148 // https://www.iana.org/assignments/media-types/application/vnd.tcpdump.pcap
149 add("application/vnd.tcpdump.pcap", "pcap");
150 add("application/vnd.tcpdump.pcap", "cap");
151 add("application/vnd.tcpdump.pcap", "dmp");
152 add("application/x-pcapng", "pcapng");
153 add("application/x-7z-compressed", "7z");
154 add("application/x-abiword", "abw");
155 add("application/x-apple-diskimage", "dmg");
156 add("application/x-bcpio", "bcpio");
157 add("application/x-bittorrent", "torrent");
158 add("application/x-cdf", "cdf");
159 add("application/x-cdlink", "vcd");
160 add("application/x-chess-pgn", "pgn");
161 add("application/x-cpio", "cpio");
162 add("application/x-debian-package", "deb");
163 add("application/x-debian-package", "udeb");
164 add("application/x-director", "dcr");
165 add("application/x-director", "dir");
166 add("application/x-director", "dxr");
167 add("application/x-dms", "dms");
168 add("application/x-doom", "wad");
169 add("application/x-dvi", "dvi");
170 add("application/x-font", "pfa");
171 add("application/x-font", "pfb");
172 add("application/x-font", "gsf");
173 add("application/x-font", "pcf");
174 add("application/x-font", "pcf.Z");
175 add("application/x-freemind", "mm");
176 // application/futuresplash isn't IANA, so application/x-futuresplash should come first.
177 add("application/x-futuresplash", "spl");
178 add("application/futuresplash", "spl");
179 add("application/x-gnumeric", "gnumeric");
180 add("application/x-go-sgf", "sgf");
181 add("application/x-graphing-calculator", "gcf");
182 add("application/x-gtar", "tgz");
183 add("application/x-gtar", "gtar");
184 add("application/x-gtar", "taz");
185 add("application/x-hdf", "hdf");
186 add("application/x-ica", "ica");
187 add("application/x-internet-signup", "ins");
188 add("application/x-internet-signup", "isp");
189 add("application/x-iphone", "iii");
190 add("application/x-iso9660-image", "iso");
191 add("application/x-jmol", "jmz");
192 add("application/x-kchart", "chrt");
193 add("application/x-killustrator", "kil");
194 add("application/x-koan", "skp");
195 add("application/x-koan", "skd");
196 add("application/x-koan", "skt");
197 add("application/x-koan", "skm");
198 add("application/x-kpresenter", "kpr");
199 add("application/x-kpresenter", "kpt");
200 add("application/x-kspread", "ksp");
201 add("application/x-kword", "kwd");
202 add("application/x-kword", "kwt");
203 add("application/x-latex", "latex");
204 add("application/x-lha", "lha");
205 add("application/x-lzh", "lzh");
206 add("application/x-lzx", "lzx");
207 add("application/x-maker", "frm");
208 add("application/x-maker", "maker");
209 add("application/x-maker", "frame");
210 add("application/x-maker", "fb");
211 add("application/x-maker", "book");
212 add("application/x-maker", "fbdoc");
213 add("application/x-mif", "mif");
214 add("application/x-mobipocket-ebook", "mobi");
215 add("application/x-ms-wmd", "wmd");
216 add("application/x-ms-wmz", "wmz");
217 add("application/x-msi", "msi");
218 add("application/x-ns-proxy-autoconfig", "pac");
219 add("application/x-nwc", "nwc");
220 add("application/x-object", "o");
221 add("application/x-oz-application", "oza");
222 add("application/x-pem-file", "pem");
223 add("application/x-pkcs12", "p12");
224 add("application/x-pkcs12", "pfx");
225 add("application/x-pkcs7-certreqresp", "p7r");
226 add("application/x-pkcs7-crl", "crl");
227 add("application/x-quicktimeplayer", "qtl");
228 add("application/x-shar", "shar");
229 add("application/x-shockwave-flash", "swf");
230 add("application/x-stuffit", "sit");
231 add("application/x-sv4cpio", "sv4cpio");
232 add("application/x-sv4crc", "sv4crc");
233 add("application/x-tar", "tar");
234 add("application/x-texinfo", "texinfo");
235 add("application/x-texinfo", "texi");
236 add("application/x-troff", "t");
237 add("application/x-troff", "roff");
238 add("application/x-troff-man", "man");
239 add("application/x-ustar", "ustar");
240 add("application/x-wais-source", "src");
241 add("application/x-wingz", "wz");
242 add("application/x-webarchive", "webarchive");
243 add("application/x-webarchive-xml", "webarchivexml");
244 add("application/x-x509-ca-cert", "crt");
245 add("application/x-x509-user-cert", "crt");
246 add("application/x-x509-server-cert", "crt");
247 add("application/x-xcf", "xcf");
248 add("application/x-xfig", "fig");
249 add("application/xhtml+xml", "xhtml");
250 add("video/3gpp", "3gpp");
251 add("video/3gpp", "3gp");
252 add("video/3gpp2", "3gpp2");
253 add("video/3gpp2", "3g2");
254 add("audio/3gpp", "3gpp");
255 add("audio/3gpp", "3gp");
256 add("audio/aac", "aac");
257 add("audio/aac-adts", "aac");
258 add("audio/amr", "amr");
259 add("audio/amr-wb", "awb");
260 add("audio/basic", "snd");
261 add("audio/flac", "flac");
262 add("application/x-flac", "flac");
263 add("audio/imelody", "imy");
264 add("audio/midi", "mid");
265 add("audio/midi", "midi");
266 add("audio/midi", "ota");
267 add("audio/midi", "kar");
268 add("audio/midi", "rtttl");
269 add("audio/midi", "xmf");
270 add("audio/mobile-xmf", "mxmf");
271 // add ".mp3" first so it will be the default for guessExtensionFromMimeType
272 add("audio/mpeg", "mp3");
273 add("audio/mpeg", "mpga");
274 add("audio/mpeg", "mpega");
275 add("audio/mpeg", "mp2");
276 add("audio/mp4", "m4a");
277 add("audio/x-m4b", "m4b");
278 add("audio/mpegurl", "m3u");
279 add("audio/ogg", "oga");
280 add("audio/opus", "opus");
281 add("audio/prs.sid", "sid");
282 add("audio/x-aiff", "aif");
283 add("audio/x-aiff", "aiff");
284 add("audio/x-aiff", "aifc");
285 add("audio/x-gsm", "gsm");
286 add("audio/x-matroska", "mka");
287 add("audio/x-mpegurl", "m3u");
288 add("audio/x-ms-wma", "wma");
289 add("audio/x-ms-wax", "wax");
290 add("audio/x-pn-realaudio", "ra");
291 add("audio/x-pn-realaudio", "rm");
292 add("audio/x-pn-realaudio", "ram");
293 add("audio/x-realaudio", "ra");
294 add("audio/x-scpls", "pls");
295 add("audio/x-sd2", "sd2");
296 add("audio/x-wav", "wav");
297 // image/bmp isn't IANA, so image/x-ms-bmp should come first.
298 add("image/x-ms-bmp", "bmp");
299 add("image/bmp", "bmp");
300 add("image/gif", "gif");
301 // image/ico isn't IANA, so image/x-icon should come first.
302 add("image/x-icon", "ico");
303 add("image/ico", "cur");
304 add("image/ico", "ico");
305 add("image/ief", "ief");
306 add("image/heic", "heic");
307 add("image/heif", "heif");
308 add("image/avif", "avif");
309 // add ".jpg" first so it will be the default for guessExtensionFromMimeType
310 add("image/jpeg", "jpg");
311 add("image/jpeg", "jpeg");
312 add("image/jpeg", "jpe");
313 add("image/jpeg", "jfif");
314 add("image/jpeg", "jif");
315 add("image/pcx", "pcx");
316 add("image/png", "png");
317 add("image/svg+xml", "svg");
318 add("image/svg+xml", "svgz");
319 add("image/tiff", "tiff");
320 add("image/tiff", "tif");
321 add("image/vnd.djvu", "djvu");
322 add("image/vnd.djvu", "djv");
323 add("image/vnd.wap.wbmp", "wbmp");
324 add("image/webp", "webp");
325 add("image/x-cmu-raster", "ras");
326 add("image/x-coreldraw", "cdr");
327 add("image/x-coreldrawpattern", "pat");
328 add("image/x-coreldrawtemplate", "cdt");
329 add("image/x-corelphotopaint", "cpt");
330 add("image/x-jg", "art");
331 add("image/x-jng", "jng");
332 add("image/x-photoshop", "psd");
333 add("image/x-portable-anymap", "pnm");
334 add("image/x-portable-bitmap", "pbm");
335 add("image/x-portable-graymap", "pgm");
336 add("image/x-portable-pixmap", "ppm");
337 add("image/x-rgb", "rgb");
338 add("image/x-xbitmap", "xbm");
339 add("image/x-xpixmap", "xpm");
340 add("image/x-xwindowdump", "xwd");
341 add("message/rfc822", "eml");
342 add("message/rfc822", "mime");
343 add("model/iges", "igs");
344 add("model/iges", "iges");
345 add("model/mesh", "msh");
346 add("model/mesh", "mesh");
347 add("model/mesh", "silo");
348 add("text/calendar", "ics");
349 add("text/calendar", "icz");
350 add("text/comma-separated-values", "csv");
351 add("text/css", "css");
352 add("text/html", "htm");
353 add("text/html", "html");
354 add("text/h323", "323");
355 add("text/iuls", "uls");
356 add("text/mathml", "mml");
357 // add ".txt" first so it will be the default for guessExtensionFromMimeType
358 add("text/plain", "txt");
359 add("text/plain", "asc");
360 add("text/plain", "text");
361 add("text/plain", "diff");
362 add("text/plain", "po"); // reserve "pot" for vnd.ms-powerpoint
363 add("text/richtext", "rtx");
364 add("text/rtf", "rtf");
365 add("text/text", "phps");
366 add("text/tab-separated-values", "tsv");
367 add("text/xml", "xml");
368 add("text/x-bibtex", "bib");
369 add("text/x-boo", "boo");
370 add("text/x-c++hdr", "hpp");
371 add("text/x-c++hdr", "h++");
372 add("text/x-c++hdr", "hxx");
373 add("text/x-c++hdr", "hh");
374 add("text/x-c++src", "cpp");
375 add("text/x-c++src", "c++");
376 add("text/x-c++src", "cc");
377 add("text/x-c++src", "cxx");
378 add("text/x-chdr", "h");
379 add("text/x-component", "htc");
380 add("text/x-csh", "csh");
381 add("text/x-csrc", "c");
382 add("text/x-dsrc", "d");
383 add("text/x-haskell", "hs");
384 add("text/x-java", "java");
385 add("text/x-literate-haskell", "lhs");
386 add("text/x-moc", "moc");
387 add("text/x-pascal", "p");
388 add("text/x-pascal", "pas");
389 add("text/x-pcs-gcd", "gcd");
390 add("text/x-setext", "etx");
391 add("text/x-tcl", "tcl");
392 add("text/x-tex", "tex");
393 add("text/x-tex", "ltx");
394 add("text/x-tex", "sty");
395 add("text/x-tex", "cls");
396 add("text/x-vcalendar", "vcs");
397 add("text/x-vcard", "vcf");
398 add("video/avi", "avi");
399 add("video/dl", "dl");
400 add("video/dv", "dif");
401 add("video/dv", "dv");
402 add("video/fli", "fli");
403 add("video/m4v", "m4v");
404 add("video/mp2ts", "ts");
405 add("video/ogg", "ogv");
406 add("video/mpeg", "mpeg");
407 add("video/mpeg", "mpg");
408 add("video/mpeg", "mpe");
409 add("video/mp4", "mp4");
410 add("video/mpeg", "VOB");
411 add("video/quicktime", "qt");
412 add("video/quicktime", "mov");
413 add("video/vnd.mpegurl", "mxu");
414 add("video/webm", "webm");
415 add("video/x-la-asf", "lsf");
416 add("video/x-la-asf", "lsx");
417 add("video/x-matroska", "mkv");
418 add("video/x-mng", "mng");
419 add("video/x-ms-asf", "asf");
420 add("video/x-ms-asf", "asx");
421 add("video/x-ms-wm", "wm");
422 add("video/x-ms-wmv", "wmv");
423 add("video/x-ms-wmx", "wmx");
424 add("video/x-ms-wvx", "wvx");
425 add("video/x-sgi-movie", "movie");
426 add("video/x-webex", "wrf");
427 add("x-conference/x-cooltalk", "ice");
428 add("x-epoc/x-sisx-app", "sisx");
429 applyOverrides();
430 }
431
432 // mime types that are more reliant by path
433 private static final Collection<String> PATH_PRECEDENCE_MIME_TYPE = List.of("audio/x-m4b");
434
435 private static void add(String mimeType, String extension) {
436 // If we have an existing x -> y mapping, we do not want to
437 // override it with another mapping x -> y2.
438 // If a mime type maps to several extensions
439 // the first extension added is considered the most popular
440 // so we do not want to overwrite it later.
441 if (!mimeTypeToExtensionMap.containsKey(mimeType)) {
442 mimeTypeToExtensionMap.put(mimeType, extension);
443 }
444 if (!extensionToMimeTypeMap.containsKey(extension)) {
445 extensionToMimeTypeMap.put(extension, mimeType);
446 }
447 }
448
449 private static InputStream getContentTypesPropertiesStream() {
450 // User override?
451 String userTable = System.getProperty("content.types.user.table");
452 if (userTable != null) {
453 File f = new File(userTable);
454 if (f.exists()) {
455 try {
456 return new FileInputStream(f);
457 } catch (IOException ignored) {
458 }
459 }
460 }
461 // Standard location?
462 File f =
463 new File(
464 System.getProperty("java.home"),
465 "lib" + File.separator + "content-types.properties");
466 if (f.exists()) {
467 try {
468 return new FileInputStream(f);
469 } catch (IOException ignored) {
470 }
471 }
472 return null;
473 }
474
475 /**
476 * This isn't what the RI does. The RI doesn't have hard-coded defaults, so supplying your own
477 * "content.types.user.table" means you don't get any of the built-ins, and the built-ins come
478 * from "$JAVA_HOME/lib/content-types.properties".
479 */
480 private static void applyOverrides() {
481 // Get the appropriate InputStream to read overrides from, if any.
482 InputStream stream = getContentTypesPropertiesStream();
483 if (stream == null) {
484 return;
485 }
486 try {
487 try {
488 // Read the properties file...
489 Properties overrides = new Properties();
490 overrides.load(stream);
491 // And translate its mapping to ours...
492 for (Map.Entry<Object, Object> entry : overrides.entrySet()) {
493 String extension = (String) entry.getKey();
494 String mimeType = (String) entry.getValue();
495 add(mimeType, extension);
496 }
497 } finally {
498 stream.close();
499 }
500 } catch (IOException ignored) {
501 }
502 }
503
504 private MimeUtils() {}
505
506 /**
507 * Returns true if the given MIME type has an entry in the map.
508 *
509 * @param mimeType A MIME type (i.e. text/plain)
510 * @return True iff there is a mimeType entry in the map.
511 */
512 public static boolean hasMimeType(String mimeType) {
513 if (mimeType == null || mimeType.isEmpty()) {
514 return false;
515 }
516 return mimeTypeToExtensionMap.containsKey(mimeType);
517 }
518
519 /**
520 * Returns the MIME type for the given extension.
521 *
522 * @param extension A file extension without the leading '.'
523 * @return The MIME type for the given extension or null iff there is none.
524 */
525 public static String guessMimeTypeFromExtension(String extension) {
526 if (extension == null || extension.isEmpty()) {
527 return null;
528 }
529 return extensionToMimeTypeMap.get(extension.toLowerCase());
530 }
531
532 /**
533 * Returns true if the given extension has a registered MIME type.
534 *
535 * @param extension A file extension without the leading '.'
536 * @return True iff there is an extension entry in the map.
537 */
538 public static boolean hasExtension(String extension) {
539 if (extension == null || extension.isEmpty()) {
540 return false;
541 }
542 return extensionToMimeTypeMap.containsKey(extension);
543 }
544
545 /**
546 * Returns the registered extension for the given MIME type. Note that some MIME types map to
547 * multiple extensions. This call will return the most common extension for the given MIME type.
548 *
549 * @param mimeType A MIME type (i.e. text/plain)
550 * @return The extension for the given MIME type or null iff there is none.
551 */
552 public static String guessExtensionFromMimeType(String mimeType) {
553 if (mimeType == null || mimeType.isEmpty()) {
554 return null;
555 }
556 return mimeTypeToExtensionMap.get(mimeType.split(";")[0]);
557 }
558
559 public static String guessMimeTypeFromUriAndMime(
560 final Context context, final Uri uri, final String mime) {
561 Log.d(Config.LOGTAG, "guessMimeTypeFromUriAndMime(" + uri + "," + mime + ")");
562 final String mimeFromUri = guessMimeTypeFromUri(context, uri);
563 Log.d(Config.LOGTAG, "mimeFromUri:" + mimeFromUri);
564 if (PATH_PRECEDENCE_MIME_TYPE.contains(mimeFromUri)) {
565 return mimeFromUri;
566 } else if (mime == null || mime.equals("application/octet-stream")) {
567 return mimeFromUri;
568 } else {
569 return mime;
570 }
571 }
572
573 public static String guessMimeTypeFromUri(final Context context, final Uri uri) {
574 final String mimeTypeContentResolver = guessFromContentResolver(context, uri);
575 final String mimeTypeFromQueryParameter = uri.getQueryParameter("mimeType");
576 final String name = "content".equals(uri.getScheme()) ? getDisplayName(context, uri) : null;
577 final String mimeTypeFromName = Strings.isNullOrEmpty(name) ? null : guessFromPath(name);
578 final String path = uri.getPath();
579 final String mimeTypeFromPath = Strings.isNullOrEmpty(path) ? null : guessFromPath(path);
580 if (PATH_PRECEDENCE_MIME_TYPE.contains(mimeTypeFromName)) {
581 return mimeTypeFromName;
582 }
583 if (PATH_PRECEDENCE_MIME_TYPE.contains(mimeTypeFromPath)) {
584 return mimeTypeFromPath;
585 }
586 if (mimeTypeContentResolver != null
587 && !"application/octet-stream".equals(mimeTypeContentResolver)) {
588 return mimeTypeContentResolver;
589 }
590 if (mimeTypeFromName != null) {
591 return mimeTypeFromName;
592 }
593 if (mimeTypeFromQueryParameter != null) {
594 return mimeTypeFromQueryParameter;
595 }
596 return mimeTypeFromPath;
597 }
598
599 private static String guessFromContentResolver(final Context context, final Uri uri) {
600 try {
601 return context.getContentResolver().getType(uri);
602 } catch (final Throwable e) {
603 return null;
604 }
605 }
606
607 private static String getDisplayName(final Context context, final Uri uri) {
608 try (final Cursor cursor =
609 context.getContentResolver().query(uri, null, null, null, null)) {
610 if (cursor != null && cursor.moveToFirst()) {
611 final int index = cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
612 if (index == -1) {
613 return null;
614 }
615 return cursor.getString(index);
616 }
617 } catch (final Exception e) {
618 return null;
619 }
620 return null;
621 }
622
623 private static String guessFromPath(final String path) {
624 final int start = path.lastIndexOf('.') + 1;
625 if (start < path.length()) {
626 return MimeUtils.guessMimeTypeFromExtension(path.substring(start));
627 }
628 return null;
629 }
630
631 public static String extractRelevantExtension(final String path) {
632 return extractRelevantExtension(path, false);
633 }
634
635 public static String extractRelevantExtension(
636 final String path, final boolean ignoreCryptoExtension) {
637 if (Strings.isNullOrEmpty(path)) {
638 return null;
639 }
640
641 final String filenameQueryAnchor = path.substring(path.lastIndexOf('/') + 1);
642 final String filenameQuery = cutBefore(filenameQueryAnchor, '#');
643 final String filename = cutBefore(filenameQuery, '?');
644 final int dotPosition = filename.lastIndexOf('.');
645
646 if (dotPosition == -1) {
647 return null;
648 }
649 final String extension = filename.substring(dotPosition + 1);
650 // we want the real file extension, not the crypto one
651 if (ignoreCryptoExtension && Transferable.VALID_CRYPTO_EXTENSIONS.contains(extension)) {
652 return extractRelevantExtension(filename.substring(0, dotPosition));
653 } else {
654 return extension;
655 }
656 }
657
658 private static String cutBefore(final String input, final char c) {
659 final int position = input.indexOf(c);
660 if (position > 0) {
661 return input.substring(0, position);
662 } else {
663 return input;
664 }
665 }
666}