diff options
Diffstat (limited to 'src/tools/android/java/com/google')
-rw-r--r-- | src/tools/android/java/com/google/devtools/build/android/BUILD | 1 | ||||
-rw-r--r-- | src/tools/android/java/com/google/devtools/build/android/ResourceShrinker.java | 1096 |
2 files changed, 1097 insertions, 0 deletions
diff --git a/src/tools/android/java/com/google/devtools/build/android/BUILD b/src/tools/android/java/com/google/devtools/build/android/BUILD index 7d5d18991c..74c12552bf 100644 --- a/src/tools/android/java/com/google/devtools/build/android/BUILD +++ b/src/tools/android/java/com/google/devtools/build/android/BUILD @@ -39,6 +39,7 @@ java_library( "//src/main/java/com/google/devtools/common/options", "//third_party:android_common", "//third_party:apache_commons_compress", + "//third_party:asm", "//third_party:guava", "//third_party:jsr305", ], diff --git a/src/tools/android/java/com/google/devtools/build/android/ResourceShrinker.java b/src/tools/android/java/com/google/devtools/build/android/ResourceShrinker.java new file mode 100644 index 0000000000..08decb2f4d --- /dev/null +++ b/src/tools/android/java/com/google/devtools/build/android/ResourceShrinker.java @@ -0,0 +1,1096 @@ +// Copyright 2015 The Bazel Authors. All rights reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package com.google.devtools.build.android; + +import static com.android.SdkConstants.ANDROID_STYLE_RESOURCE_PREFIX; +import static com.android.SdkConstants.ANDROID_URI; +import static com.android.SdkConstants.ATTR_NAME; +import static com.android.SdkConstants.ATTR_PARENT; +import static com.android.SdkConstants.ATTR_TYPE; +import static com.android.SdkConstants.DOT_CLASS; +import static com.android.SdkConstants.DOT_GIF; +import static com.android.SdkConstants.DOT_JPEG; +import static com.android.SdkConstants.DOT_JPG; +import static com.android.SdkConstants.DOT_PNG; +import static com.android.SdkConstants.DOT_XML; +import static com.android.SdkConstants.FD_RES_VALUES; +import static com.android.SdkConstants.PREFIX_ANDROID; +import static com.android.SdkConstants.STYLE_RESOURCE_PREFIX; +import static com.android.SdkConstants.TAG_ITEM; +import static com.android.SdkConstants.TAG_RESOURCES; +import static com.android.SdkConstants.TAG_STYLE; +import static com.android.utils.SdkUtils.endsWith; +import static com.android.utils.SdkUtils.endsWithIgnoreCase; +import static com.google.common.base.Charsets.UTF_8; + +import com.google.common.base.Charsets; +import com.google.common.base.Joiner; +import com.google.common.collect.Lists; +import com.google.common.collect.Maps; +import com.google.common.collect.Sets; +import com.google.common.io.ByteStreams; +import com.google.common.io.Closeables; +import com.google.common.io.Files; + +import com.android.annotations.NonNull; +import com.android.annotations.Nullable; +import com.android.annotations.VisibleForTesting; +import com.android.ide.common.resources.ResourceUrl; +import com.android.ide.common.resources.configuration.DensityQualifier; +import com.android.ide.common.resources.configuration.FolderConfiguration; +import com.android.ide.common.resources.configuration.ResourceQualifier; +import com.android.ide.common.xml.XmlPrettyPrinter; +import com.android.resources.FolderTypeRelationship; +import com.android.resources.ResourceFolderType; +import com.android.resources.ResourceType; +import com.android.utils.XmlUtils; + +import org.objectweb.asm.ClassReader; +import org.objectweb.asm.ClassVisitor; +import org.objectweb.asm.MethodVisitor; +import org.objectweb.asm.Opcodes; +import org.w3c.dom.Attr; +import org.w3c.dom.Document; +import org.w3c.dom.Element; +import org.w3c.dom.NamedNodeMap; +import org.w3c.dom.Node; +import org.w3c.dom.NodeList; +import org.xml.sax.SAXException; + +import java.io.BufferedReader; +import java.io.File; +import java.io.FileInputStream; +import java.io.IOException; +import java.nio.charset.Charset; +import java.nio.file.Path; +import java.util.ArrayList; +import java.util.Collections; +import java.util.IdentityHashMap; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.zip.ZipEntry; +import java.util.zip.ZipInputStream; + +import javax.xml.parsers.ParserConfigurationException; + +/** + * Class responsible for searching through a Gradle built tree (after resource merging, compilation + * and ProGuarding has been completed, but before final .apk assembly), which figures out which + * resources if any are unused, and removes them. <p> It does this by examining <ul> <li>The merged + * manifest, to find root resource references (such as drawables used for activity icons)</li> + * <li>The merged R class (to find the actual integer constants assigned to resources)</li> <li>The + * ProGuard log files (to find the mapping from original symbol names to short names)</li>* <li>The + * merged resources (to find which resources reference other resources, e.g. drawable state lists + * including other drawables, or layouts including other layouts, or styles referencing other + * drawables, or menus items including action layouts, etc.)</li> <li>The ProGuard output classes + * (to find resource references in code that are actually reachable)</li> </ul> From all this, it + * builds up a reference graph, and based on the root references (e.g. from the manifest and from + * the remaining code) it computes which resources are actually reachable in the app, and anything + * that is not reachable is then marked for deletion. <p> A resource is referenced in code if either + * the field R.type.name is referenced (which is the case for non-final resource references, e.g. in + * libraries), or if the corresponding int value is referenced (for final resource values). We check + * this by looking at the ProGuard output classes with an ASM visitor. One complication is that code + * can also call {@code Resources#getIdentifier(String,String,String)} where they can pass in the + * names of resources to look up. To handle this scenario, we use the ClassVisitor to see if there + * are any calls to the specific {@code Resources#getIdentifier} method. If not, great, the usage + * analysis is completely accurate. If we <b>do</b> find one, we check <b>all</b> the string + * constants found anywhere in the app, and look to see if any look relevant. For example, if we + * find the string "string/foo" or "my.pkg:string/foo", we will then mark the string resource named + * foo (if any) as potentially used. Similarly, if we find just "foo" or "/foo", we will mark + * <b>all</b> resources named "foo" as potentially used. However, if the string is "bar/foo" or " + * foo " these strings are ignored. This means we can potentially miss resources usages where the + * resource name is completed computed (e.g. by concatenating individual characters or taking + * substrings of strings that do not look like resource names), but that seems extremely unlikely to + * be a real-world scenario. <p> For now, for reasons detailed in the code, this only applies to + * file-based resources like layouts, menus and drawables, not value-based resources like strings + * and dimensions. + */ +public class ResourceShrinker { + + public static final int TYPICAL_RESOURCE_COUNT = 200; + private final Path rTxt; + private final Path proguardMapping; + private final Path classesJar; + private final Path mergedManifest; + private final Path mergedResourceDir; + private final String rPackagePath; + + /** + * The computed set of unused resources + */ + private List<Resource> unused; + /** + * List of all known resources (parsed from R.java) + */ + private List<Resource> resources = Lists.newArrayListWithExpectedSize(TYPICAL_RESOURCE_COUNT); + /** + * Map from R field value to corresponding resource + */ + private Map<Integer, Resource> valueToResource = + Maps.newHashMapWithExpectedSize(TYPICAL_RESOURCE_COUNT); + /** + * Map from resource type to map from resource name to resource object + */ + private Map<ResourceType, Map<String, Resource>> typeToName = + Maps.newEnumMap(ResourceType.class); + /** + * Map from resource class owners (VM format class) to corresponding resource types. This will + * typically be the fully qualified names of the R classes, as well as any renamed versions of + * those discovered in the mapping.txt file from ProGuard + */ + private Map<String, ResourceType> resourceClassOwners = Maps.newHashMapWithExpectedSize(20); + + public ResourceShrinker( + @NonNull Path rTxt, + @NonNull Path classesJar, + @NonNull Path manifest, + @Nullable Path mapping, + @NonNull Path resources, + @NonNull String rPackageName) { + this.rTxt = rTxt; + proguardMapping = mapping; + this.classesJar = classesJar; + mergedManifest = manifest; + mergedResourceDir = resources; + this.rPackagePath = rPackageName.replace('.', '/'); + } + + public void shrink(Path destinationDir) throws IOException, + ParserConfigurationException, SAXException { + parseResourceTxtFile(rTxt); + recordMapping(proguardMapping); + recordUsages(classesJar); + recordManifestUsages(mergedManifest); + recordResources(mergedResourceDir); + keepPossiblyReferencedResources(); + dumpReferences(); + findUnused(); + removeUnused(destinationDir); + } + + /** + * Remove resources (already identified by {@link #shrink(Path)}). + * + * <p>This task will copy all remaining used resources over from the full resource directory to a + * new reduced resource directory. However, it can't just delete the resources, because it has no + * way to tell aapt to continue to use the same id's for the resources. When we re-run aapt on the + * stripped resource directory, it will assign new id's to some of the resources (to fill the + * gaps) which means the resource id's no longer match the constants compiled into the dex files, + * and as a result, the app crashes at runtime. <p> Therefore, it needs to preserve all id's by + * actually keeping all the resource names. It can still save a lot of space by making these + * resources tiny; e.g. all strings are set to empty, all styles, arrays and plurals are set to + * not contain any children, and most importantly, all file based resources like bitmaps and + * layouts are replaced by simple resource aliases which just point to @null. + * + * @param destination directory to copy resources into; if null, delete resources in place + */ + private void removeUnused(Path destination) throws IOException, + ParserConfigurationException, SAXException { + assert unused != null; // should always call analyze() first + int resourceCount = unused.size() * 4; // *4: account for some resource folder repetition + Set<File> skip = Sets.newHashSetWithExpectedSize(resourceCount); + Set<File> rewrite = Sets.newHashSetWithExpectedSize(resourceCount); + for (Resource resource : unused) { + if (resource.declarations != null) { + for (File file : resource.declarations) { + String folder = file.getParentFile().getName(); + ResourceFolderType folderType = ResourceFolderType.getFolderType(folder); + if (folderType != null && folderType != ResourceFolderType.VALUES) { + System.out.println("Deleted unused resource " + file); + assert skip != null; + skip.add(file); + } else { + // Can't delete values immediately; there can be many resources + // in this file, so we have to process them all + rewrite.add(file); + } + } + } + } + // Special case the base values.xml folder + File values = new File(mergedResourceDir.toFile(), + FD_RES_VALUES + File.separatorChar + "values.xml"); + boolean valuesExists = values.exists(); + if (valuesExists) { + rewrite.add(values); + } + Map<File, String> rewritten = Maps.newHashMapWithExpectedSize(rewrite.size()); + // Delete value resources: Must rewrite the XML files + for (File file : rewrite) { + String xml = Files.toString(file, UTF_8); + Document document = XmlUtils.parseDocument(xml, true); + Element root = document.getDocumentElement(); + if (root != null && TAG_RESOURCES.equals(root.getTagName())) { + List<String> removed = Lists.newArrayList(); + stripUnused(root, removed); + System.out.println("Removed " + removed.size() + " unused resources from " + file + ":\n " + + Joiner.on(", ").join(removed)); + String formatted = XmlPrettyPrinter.prettyPrint(document, xml.endsWith("\n")); + rewritten.put(file, formatted); + } + } + if (valuesExists) { + String xml = rewritten.get(values); + if (xml == null) { + xml = Files.toString(values, UTF_8); + } + Document document = XmlUtils.parseDocument(xml, true); + Element root = document.getDocumentElement(); + for (Resource resource : resources) { + if (resource.type == ResourceType.ID && !resource.hasDefault) { + Element item = document.createElement(TAG_ITEM); + item.setAttribute(ATTR_TYPE, resource.type.getName()); + item.setAttribute(ATTR_NAME, resource.name); + root.appendChild(item); + } else if (!resource.reachable + && !resource.hasDefault + && resource.type != ResourceType.DECLARE_STYLEABLE + && resource.type != ResourceType.STYLE + && resource.type != ResourceType.PLURALS + && resource.type != ResourceType.ARRAY + && resource.isRelevantType()) { + Element item = document.createElement(TAG_ITEM); + item.setAttribute(ATTR_TYPE, resource.type.getName()); + item.setAttribute(ATTR_NAME, resource.name); + root.appendChild(item); + String s = "@null"; + item.appendChild(document.createTextNode(s)); + } + } + String formatted = XmlPrettyPrinter.prettyPrint(document, xml.endsWith("\n")); + rewritten.put(values, formatted); + } + filteredCopy(mergedResourceDir.toFile(), destination, skip, rewritten); + } + + /** + * Copies one resource directory tree into another; skipping some files, replacing the contents of + * some, and passing everything else through unmodified + */ + private static void filteredCopy(File source, Path destination, Set<File> skip, + Map<File, String> replace) throws IOException { + + File destinationFile = destination.toFile(); + if (source.isDirectory()) { + File[] children = source.listFiles(); + if (children != null) { + if (!destinationFile.exists()) { + boolean success = destinationFile.mkdirs(); + if (!success) { + throw new IOException("Could not create " + destination); + } + } + for (File child : children) { + filteredCopy(child, destination.resolve(child.getName()), skip, replace); + } + } + } else if (!skip.contains(source) && source.isFile()) { + String contents = replace.get(source); + if (contents != null) { + Files.write(contents, destinationFile, Charsets.UTF_8); + } else { + Files.copy(source, destinationFile); + } + } + } + + private void stripUnused(Element element, List<String> removed) { + ResourceType type = getResourceType(element); + if (type == ResourceType.ATTR) { + // Not yet properly handled + return; + } + Resource resource = getResource(element); + if (resource != null) { + if (resource.type == ResourceType.DECLARE_STYLEABLE + || resource.type == ResourceType.ATTR) { + // Don't strip children of declare-styleable; we're not correctly + // tracking field references of the R_styleable_attr fields yet + return; + } + if (!resource.reachable + && (resource.type == ResourceType.STYLE + || resource.type == ResourceType.PLURALS + || resource.type == ResourceType.ARRAY)) { + NodeList children = element.getChildNodes(); + for (int i = children.getLength() - 1; i >= 0; i--) { + Node child = children.item(i); + element.removeChild(child); + } + return; + } + } + NodeList children = element.getChildNodes(); + for (int i = children.getLength() - 1; i >= 0; i--) { + Node child = children.item(i); + if (child.getNodeType() == Node.ELEMENT_NODE) { + stripUnused((Element) child, removed); + } + } + if (resource != null && !resource.reachable) { + removed.add(resource.getUrl()); + // for themes etc where .'s have been replaced by _'s + String name = element.getAttribute(ATTR_NAME); + if (name.isEmpty()) { + name = resource.name; + } + Node nextSibling = element.getNextSibling(); + Node parent = element.getParentNode(); + NodeList oldChildren = element.getChildNodes(); + parent.removeChild(element); + Document document = element.getOwnerDocument(); + element = document.createElement("item"); + for (int i = 0; i < oldChildren.getLength(); i++) { + element.appendChild(oldChildren.item(i)); + } + element.setAttribute(ATTR_NAME, name); + element.setAttribute(ATTR_TYPE, resource.type.getName()); + String text = null; + switch (resource.type) { + case BOOL: + text = "true"; + break; + case DIMEN: + text = "0dp"; + break; + case INTEGER: + text = "0"; + break; + } + element.setTextContent(text); + parent.insertBefore(element, nextSibling); + } + } + + private static String getFieldName(Element element) { + return getFieldName(element.getAttribute(ATTR_NAME)); + } + + @Nullable + private Resource getResource(Element element) { + ResourceType type = getResourceType(element); + if (type != null) { + String name = getFieldName(element); + return getResource(type, name); + } + return null; + } + + private static ResourceType getResourceType(Element element) { + String tagName = element.getTagName(); + switch (tagName) { + case TAG_ITEM: + String typeName = element.getAttribute(ATTR_TYPE); + if (!typeName.isEmpty()) { + return ResourceType.getEnum(typeName); + } + break; + case "string-array": + case "integer-array": + return ResourceType.ARRAY; + default: + return ResourceType.getEnum(tagName); + } + return null; + } + + private void findUnused() { + List<Resource> roots = Lists.newArrayList(); + for (Resource resource : resources) { + if (resource.reachable && resource.type != ResourceType.ID + && resource.type != ResourceType.ATTR) { + roots.add(resource); + } + } + System.out.println("The root reachable resources are: " + Joiner.on(",\n ").join(roots)); + Map<Resource, Boolean> seen = new IdentityHashMap<>(resources.size()); + for (Resource root : roots) { + visit(root, seen); + } + List<Resource> unused = Lists.newArrayListWithExpectedSize(resources.size()); + for (Resource resource : resources) { + if (!resource.reachable && resource.isRelevantType()) { + unused.add(resource); + } + } + this.unused = unused; + } + + private static void visit(Resource root, Map<Resource, Boolean> seen) { + if (seen.containsKey(root)) { + return; + } + seen.put(root, Boolean.TRUE); + root.reachable = true; + if (root.references != null) { + for (Resource referenced : root.references) { + visit(referenced, seen); + } + } + } + + private void dumpReferences() { + for (Resource resource : resources) { + if (resource.references != null) { + System.out.println(resource + " => " + resource.references); + } + } + } + + private void keepPossiblyReferencedResources() { + if (!mFoundGetIdentifier || mStrings == null) { + // No calls to android.content.res.Resources#getIdentifier; no need + // to worry about string references to resources + return; + } + List<String> strings = new ArrayList<String>(mStrings); + Collections.sort(strings); + System.out.println("android.content.res.Resources#getIdentifier present: " + + mFoundGetIdentifier); + System.out.println("Referenced Strings:"); + for (String s : strings) { + s = s.trim().replace("\n", "\\n"); + if (s.length() > 40) { + s = s.substring(0, 37) + "..."; + } else if (s.isEmpty()) { + continue; + } + System.out.println(" " + s); + } + Set<String> names = Sets.newHashSetWithExpectedSize(50); + for (Map<String, Resource> map : typeToName.values()) { + names.addAll(map.keySet()); + } + for (String string : mStrings) { + // Check whether the string looks relevant + // We consider three types of strings: + // (1) simple resource names, e.g. "foo" from @layout/foo + // These might be the parameter to a getIdentifier() call, or could + // be composed into a fully qualified resource name for the getIdentifier() + // method. We match these for *all* resource types. + // (2) Relative source names, e.g. layout/foo, from @layout/foo + // These might be composed into a fully qualified resource name for + // getIdentifier(). + // (3) Fully qualified resource names of the form package:type/name. + int n = string.length(); + boolean justName = true; + boolean haveSlash = false; + for (int i = 0; i < n; i++) { + char c = string.charAt(i); + if (c == '/') { + haveSlash = true; + justName = false; + } else if (c == '.' || c == ':') { + justName = false; + } else if (!Character.isJavaIdentifierPart(c)) { + // This shouldn't happen; we've filtered out these strings in + // the {@link #referencedString} method + assert false : string; + break; + } + } + String name; + if (justName) { + // Check name (below) + name = string; + } else if (!haveSlash) { + // If we have more than just a symbol name, we expect to also see a slash + //noinspection UnnecessaryContinue + continue; + } else { + // Try to pick out the resource name pieces; if we can find the + // resource type unambiguously; if not, just match on names + int slash = string.indexOf('/'); + assert slash != -1; // checked with haveSlash above + name = string.substring(slash + 1); + if (name.isEmpty() || !names.contains(name)) { + continue; + } + // See if have a known specific resource type + if (slash > 0) { + int colon = string.indexOf(':'); + String typeName = string.substring(colon != -1 ? colon + 1 : 0, slash); + ResourceType type = ResourceType.getEnum(typeName); + if (type == null) { + continue; + } + Resource resource = getResource(type, name); + if (resource != null) { + System.out.println("Marking " + resource + " used because it " + + "matches string pool constant " + string); + } + markReachable(resource); + continue; + } + // fall through and check the name + } + if (names.contains(name)) { + for (Map<String, Resource> map : typeToName.values()) { + Resource resource = map.get(string); + if (resource != null) { + System.out.println("Marking " + resource + " used because it " + + "matches string pool constant " + string); + } + markReachable(resource); + } + } else if (Character.isDigit(name.charAt(0))) { + // Just a number? There are cases where it calls getIdentifier by + // a String number; see for example SuggestionsAdapter in the support + // library which reports supporting a string like "2130837524" and + // "android.resource://com.android.alarmclock/2130837524". + try { + int id = Integer.parseInt(name); + if (id != 0) { + markReachable(valueToResource.get(id)); + } + } catch (NumberFormatException e) { + // pass + } + } + } + } + + private void recordResources(Path resDir) + throws IOException, SAXException, ParserConfigurationException { + + File[] resourceFolders = resDir.toFile().listFiles(); + if (resourceFolders != null) { + for (File folder : resourceFolders) { + ResourceFolderType folderType = ResourceFolderType.getFolderType(folder.getName()); + if (folderType != null) { + recordResources(folderType, folder); + } + } + } + } + + private void recordResources(@NonNull ResourceFolderType folderType, File folder) + throws ParserConfigurationException, SAXException, IOException { + File[] files = folder.listFiles(); + FolderConfiguration config = FolderConfiguration.getConfigForFolder(folder.getName()); + boolean isDefaultFolder = false; + if (config != null) { + isDefaultFolder = true; + for (int i = 0, n = FolderConfiguration.getQualifierCount(); i < n; i++) { + ResourceQualifier qualifier = config.getQualifier(i); + // Densities are special: even if they're present in just (say) drawable-hdpi + // we'll match it on any other density + if (qualifier != null && !(qualifier instanceof DensityQualifier)) { + isDefaultFolder = false; + break; + } + } + } + if (files != null) { + for (File file : files) { + String path = file.getPath(); + boolean isXml = endsWithIgnoreCase(path, DOT_XML); + Resource from = null; + // Record resource for the whole file + if (folderType != ResourceFolderType.VALUES + && (isXml + || endsWith(path, DOT_PNG) //also true for endsWith(name, DOT_9PNG) + || endsWith(path, DOT_JPG) + || endsWith(path, DOT_GIF) + || endsWith(path, DOT_JPEG))) { + List<ResourceType> types = FolderTypeRelationship.getRelatedResourceTypes( + folderType); + ResourceType type = types.get(0); + assert type != ResourceType.ID : folderType; + String name = file.getName(); + name = name.substring(0, name.indexOf('.')); + Resource resource = getResource(type, name); + if (resource != null) { + resource.addLocation(file); + if (isDefaultFolder) { + resource.hasDefault = true; + } + from = resource; + } + } + if (isXml) { + // For value files, and drawables and colors etc also pull in resource + // references inside the file + recordResourcesUsages(file, isDefaultFolder, from); + } + } + } + } + + private void recordMapping(@Nullable Path mapping) throws IOException { + if (mapping == null || !mapping.toFile().exists()) { + return; + } + final String arrowIndicator = " -> "; + final String resourceIndicator = ".R$"; + for (String line : Files.readLines(mapping.toFile(), UTF_8)) { + if (line.startsWith(" ") || line.startsWith("\t")) { + continue; + } + int index = line.indexOf(resourceIndicator); + if (index == -1) { + continue; + } + int arrow = line.indexOf(arrowIndicator, index + 3); + if (arrow == -1) { + continue; + } + String typeName = line.substring(index + resourceIndicator.length(), arrow); + ResourceType type = ResourceType.getEnum(typeName); + if (type == null) { + continue; + } + int end = line.indexOf(':', arrow + arrowIndicator.length()); + if (end == -1) { + end = line.length(); + } + String target = line.substring(arrow + arrowIndicator.length(), end).trim(); + String ownerName = target.replace('.', '/'); + resourceClassOwners.put(ownerName, type); + } + } + + private void recordManifestUsages(Path manifest) + throws IOException, ParserConfigurationException, SAXException { + String xml = Files.toString(manifest.toFile(), UTF_8); + Document document = XmlUtils.parseDocument(xml, true); + recordManifestUsages(document.getDocumentElement()); + } + + private void recordResourcesUsages(@NonNull File file, boolean isDefaultFolder, + @Nullable Resource from) + throws IOException, ParserConfigurationException, SAXException { + String xml = Files.toString(file, UTF_8); + Document document = XmlUtils.parseDocument(xml, true); + recordResourceReferences(file, isDefaultFolder, document.getDocumentElement(), from); + } + + @Nullable + private Resource getResource(@NonNull ResourceType type, @NonNull String name) { + Map<String, Resource> nameMap = typeToName.get(type); + if (nameMap != null) { + return nameMap.get(getFieldName(name)); + } + return null; + } + + @Nullable + private Resource getResource(@NonNull String possibleUrlReference) { + ResourceUrl url = ResourceUrl.parse(possibleUrlReference); + if (url != null && !url.framework) { + return getResource(url.type, url.name); + } + return null; + } + + private void recordManifestUsages(Node node) { + short nodeType = node.getNodeType(); + if (nodeType == Node.ELEMENT_NODE) { + Element element = (Element) node; + NamedNodeMap attributes = element.getAttributes(); + for (int i = 0, n = attributes.getLength(); i < n; i++) { + Attr attr = (Attr) attributes.item(i); + markReachable(getResource(attr.getValue())); + } + } else if (nodeType == Node.TEXT_NODE) { + // Does this apply to any manifests?? + String text = node.getNodeValue().trim(); + markReachable(getResource(text)); + } + NodeList children = node.getChildNodes(); + for (int i = 0, n = children.getLength(); i < n; i++) { + Node child = children.item(i); + recordManifestUsages(child); + } + } + + private void recordResourceReferences(@NonNull File file, boolean isDefaultFolder, + @NonNull Node node, @Nullable Resource from) { + short nodeType = node.getNodeType(); + if (nodeType == Node.ELEMENT_NODE) { + Element element = (Element) node; + if (from != null) { + NamedNodeMap attributes = element.getAttributes(); + for (int i = 0, n = attributes.getLength(); i < n; i++) { + Attr attr = (Attr) attributes.item(i); + Resource resource = getResource(attr.getValue()); + if (resource != null) { + from.addReference(resource); + } + } + // Android Wear. We *could* limit ourselves to only doing this in files + // referenced from a manifest meta-data element, e.g. + // <meta-data android:name="com.google.android.wearable.beta.app" + // android:resource="@xml/wearable_app_desc"/> + // but given that that property has "beta" in the name, it seems likely + // to change and therefore hardcoding it for that key risks breakage + // in the future. + if ("rawPathResId".equals(element.getTagName())) { + StringBuilder sb = new StringBuilder(); + NodeList children = node.getChildNodes(); + for (int i = 0, n = children.getLength(); i < n; i++) { + Node child = children.item(i); + if (child.getNodeType() == Element.TEXT_NODE + || child.getNodeType() == Element.CDATA_SECTION_NODE) { + sb.append(child.getNodeValue()); + } + } + if (sb.length() > 0) { + Resource resource = getResource(ResourceType.RAW, sb.toString().trim()); + from.addReference(resource); + } + } + } + Resource definition = getResource(element); + if (definition != null) { + from = definition; + definition.addLocation(file); + if (isDefaultFolder) { + definition.hasDefault = true; + } + } + String tagName = element.getTagName(); + if (TAG_STYLE.equals(tagName)) { + if (element.hasAttribute(ATTR_PARENT)) { + String parent = element.getAttribute(ATTR_PARENT); + if (!parent.isEmpty() && !parent.startsWith(ANDROID_STYLE_RESOURCE_PREFIX) + && !parent.startsWith(PREFIX_ANDROID)) { + String parentStyle = parent; + if (!parentStyle.startsWith(STYLE_RESOURCE_PREFIX)) { + parentStyle = STYLE_RESOURCE_PREFIX + parentStyle; + } + Resource ps = getResource(getFieldName(parentStyle)); + if (ps != null && definition != null) { + definition.addReference(ps); + } + } + } else { + // Implicit parent styles by name + String name = getFieldName(element); + while (true) { + int index = name.lastIndexOf('_'); + if (index != -1) { + name = name.substring(0, index); + Resource ps = getResource(STYLE_RESOURCE_PREFIX + getFieldName(name)); + if (ps != null && definition != null) { + definition.addReference(ps); + } + } else { + break; + } + } + } + } + if (TAG_ITEM.equals(tagName)) { + // In style? If so the name: attribute can be a reference + if (element.getParentNode() != null + && element.getParentNode().getNodeName().equals(TAG_STYLE)) { + String name = element.getAttributeNS(ANDROID_URI, ATTR_NAME); + if (!name.isEmpty() && !name.startsWith("android:")) { + Resource resource = getResource(ResourceType.ATTR, name); + if (definition == null) { + Element style = (Element) element.getParentNode(); + definition = getResource(style); + if (definition != null) { + from = definition; + definition.addReference(resource); + } + } + } + } + } + } else if (nodeType == Node.TEXT_NODE || nodeType == Node.CDATA_SECTION_NODE) { + String text = node.getNodeValue().trim(); + Resource textResource = getResource(getFieldName(text)); + if (textResource != null && from != null) { + from.addReference(textResource); + } + } + NodeList children = node.getChildNodes(); + for (int i = 0, n = children.getLength(); i < n; i++) { + Node child = children.item(i); + recordResourceReferences(file, isDefaultFolder, child, from); + } + } + + public static String getFieldName(@NonNull String styleName) { + return styleName.replace('.', '_').replace('-', '_').replace(':', '_'); + } + + private static void markReachable(@Nullable Resource resource) { + if (resource != null) { + resource.reachable = true; + } + } + + private Set<String> mStrings; + private boolean mFoundGetIdentifier; + + private void referencedString(@NonNull String string) { + // See if the string is at all eligible; ignore strings that aren't + // identifiers (has java identifier chars and nothing but .:/), or are empty or too long + if (string.isEmpty() || string.length() > 80) { + return; + } + boolean haveIdentifierChar = false; + for (int i = 0, n = string.length(); i < n; i++) { + char c = string.charAt(i); + boolean identifierChar = Character.isJavaIdentifierPart(c); + if (!identifierChar && c != '.' && c != ':' && c != '/') { + // .:/ are for the fully qualified resuorce names + return; + } else if (identifierChar) { + haveIdentifierChar = true; + } + } + if (!haveIdentifierChar) { + return; + } + if (mStrings == null) { + mStrings = Sets.newHashSetWithExpectedSize(300); + } + mStrings.add(string); + } + + private void recordUsages(Path jarFile) throws IOException { + if (!jarFile.toFile().exists()) { + return; + } + ZipInputStream zis = null; + try { + FileInputStream fis = new FileInputStream(jarFile.toFile()); + try { + zis = new ZipInputStream(fis); + ZipEntry entry = zis.getNextEntry(); + while (entry != null) { + String name = entry.getName(); + if (name.endsWith(DOT_CLASS)) { + byte[] bytes = ByteStreams.toByteArray(zis); + if (bytes != null) { + ClassReader classReader = new ClassReader(bytes); + classReader.accept(new UsageVisitor(), 0); + } + } + entry = zis.getNextEntry(); + } + } finally { + Closeables.close(fis, true); + } + } finally { + Closeables.close(zis, true); + } + } + + private void parseResourceTxtFile(Path file) throws IOException { + BufferedReader reader = java.nio.file.Files.newBufferedReader(file, Charset.defaultCharset()); + String line; + while ((line = reader.readLine()) != null) { + String[] tokens = line.split(" "); + ResourceType type = ResourceType.getEnum(tokens[1]); + resourceClassOwners.put(rPackagePath + "/R$" + type.getName(), type); + if (type == ResourceType.STYLEABLE) { + if (tokens[0].equals("int[]")) { + addResource(ResourceType.DECLARE_STYLEABLE, tokens[2], null); + } else { + // TODO(jongerrish): Implement stripping of styleables. + } + } else { + addResource(type, tokens[2], tokens[3]); + } + } + } + + private void addResource(@NonNull ResourceType type, @NonNull String name, + @Nullable String value) { + int realValue = value != null ? Integer.decode(value) : -1; + Resource resource = getResource(type, name); + if (resource != null) { + //noinspection VariableNotUsedInsideIf + if (value != null) { + if (resource.value == -1) { + resource.value = realValue; + } else { + assert realValue == resource.value; + } + } + return; + } + resource = new Resource(type, name, realValue); + resources.add(resource); + if (realValue != -1) { + valueToResource.put(realValue, resource); + } + Map<String, Resource> nameMap = typeToName.get(type); + if (nameMap == null) { + nameMap = Maps.newHashMapWithExpectedSize(30); + typeToName.put(type, nameMap); + } + nameMap.put(name, resource); + // TODO: Assert that we don't set the same resource multiple times to different values. + // Could happen if you pass in stale data! + } + + @VisibleForTesting + List<Resource> getAllResources() { + return resources; + } + + /** + * Metadata about an Android resource + */ + public static class Resource { + + /** + * Type of resource + */ + public ResourceType type; + /** + * Name of resource + */ + public String name; + /** + * Integer id location + */ + public int value; + /** + * Whether this resource can be reached from one of the roots (manifest, code) + */ + public boolean reachable; + /** + * Whether this resource has a default definition (e.g. present in a resource folder with no + * qualifiers). For id references, an inline definition (@+id) does not count as a default + * definition. + */ + public boolean hasDefault; + /** + * Resources this resource references. For example, a layout can reference another via an + * include; a style reference in a layout references that layout style, and so on. + */ + public List<Resource> references; + public final List<File> declarations = Lists.newArrayList(); + + private Resource(ResourceType type, String name, int value) { + this.type = type; + this.name = name; + this.value = value; + } + + @Override + public String toString() { + return type + ":" + name + ":" + value; + } + + @SuppressWarnings("RedundantIfStatement") // Generated by IDE + @Override + public boolean equals(Object o) { + if (this == o) { + return true; + } + if (o == null || getClass() != o.getClass()) { + return false; + } + Resource resource = (Resource) o; + if (name != null ? !name.equals(resource.name) : resource.name != null) { + return false; + } + if (type != resource.type) { + return false; + } + return true; + } + + @Override + public int hashCode() { + int result = type != null ? type.hashCode() : 0; + result = 31 * result + (name != null ? name.hashCode() : 0); + return result; + } + + public void addLocation(@NonNull File file) { + declarations.add(file); + } + + public void addReference(@Nullable Resource resource) { + if (resource != null) { + if (references == null) { + references = Lists.newArrayList(); + } else if (references.contains(resource)) { + return; + } + references.add(resource); + } + } + + public String getUrl() { + return '@' + type.getName() + '/' + name; + } + + public boolean isRelevantType() { + return type != ResourceType.ID; // && getFolderType() != ResourceFolderType.VALUES; + } + } + + private class UsageVisitor extends ClassVisitor { + + public UsageVisitor() { + super(Opcodes.ASM4); + } + + @Override + public MethodVisitor visitMethod(int access, final String name, + String desc, String signature, String[] exceptions) { + return new MethodVisitor(Opcodes.ASM4) { + @Override + public void visitLdcInsn(Object cst) { + if (cst instanceof Integer) { + Integer value = (Integer) cst; + markReachable(valueToResource.get(value)); + } else if (cst instanceof String) { + String string = (String) cst; + referencedString(string); + } + } + + @Override + public void visitFieldInsn(int opcode, String owner, String name, String desc) { + if (opcode == Opcodes.GETSTATIC) { + ResourceType type = resourceClassOwners.get(owner); + if (type != null) { + Resource resource = getResource(type, name); + if (resource != null) { + markReachable(resource); + } + } + } + } + + @Override + public void visitMethodInsn(int opcode, String owner, String name, String desc) { + super.visitMethodInsn(opcode, owner, name, desc); + if (owner.equals("android/content/res/Resources") + && name.equals("getIdentifier") + && desc.equals( + "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)I")) { + mFoundGetIdentifier = true; + // TODO: Check previous instruction and see if we can find a literal + // String; if so, we can more accurately dispatch the resource here + // rather than having to check the whole string pool! + } + } + }; + } + } +} |