com.facebook.buck.cxx.DebugPathSanitizer.java Source code

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Here is the source code for com.facebook.buck.cxx.DebugPathSanitizer.java

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/*
 * Copyright 2016-present Facebook, Inc.
 *
 * 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.facebook.buck.cxx;

import com.facebook.buck.util.MoreCollectors;
import com.google.common.base.Function;
import com.google.common.base.Preconditions;
import com.google.common.base.Strings;
import com.google.common.collect.ImmutableBiMap;
import com.google.common.collect.ImmutableList;

import java.io.IOException;
import java.nio.file.Path;
import java.util.Map;
import java.util.Optional;
import java.util.stream.StreamSupport;

/**
 * Encapsulates all the logic to sanitize debug paths in native code.
 */
public abstract class DebugPathSanitizer {
    private final int pathSize;
    private final char separator;
    protected final Path compilationDirectory;

    public DebugPathSanitizer(char separator, int pathSize, Path compilationDirectory) {
        this.separator = separator;
        this.pathSize = pathSize;
        this.compilationDirectory = compilationDirectory;
    }

    /**
     * @return the given path as a string, expanded using {@code separator} to fulfill the required
     *     {@code pathSize}.
     */
    protected String getExpandedPath(Path path) {
        Preconditions.checkArgument(path.toString().length() <= pathSize,
                String.format("Path is too long to sanitize:\n'%s' is %d characters long, limit is %d.", path,
                        path.toString().length(), pathSize));
        return Strings.padEnd(path.toString(), pathSize, separator);
    }

    abstract Map<String, String> getCompilationEnvironment(Path workingDir, boolean shouldSanitize);

    abstract ImmutableList<String> getCompilationFlags();

    protected abstract ImmutableBiMap<Path, Path> getAllPaths(Optional<Path> workingDir);

    public String getCompilationDirectory() {
        return getExpandedPath(compilationDirectory);
    }

    public Function<String, String> sanitize(final Optional<Path> workingDir) {
        return input -> DebugPathSanitizer.this.sanitize(workingDir, input);
    }

    public ImmutableList<String> sanitizeFlags(Iterable<String> flags) {
        return StreamSupport.stream(flags.spliterator(), false).map(sanitize(Optional.empty())::apply)
                .collect(MoreCollectors.toImmutableList());
    }

    /**
     * @param workingDir the current working directory, if applicable.
     * @param contents the string to sanitize.
     * @return a string with all matching paths replaced with their sanitized versions.
     */
    public String sanitize(Optional<Path> workingDir, String contents) {
        for (Map.Entry<Path, Path> entry : getAllPaths(workingDir).entrySet()) {
            String replacement = entry.getValue().toString();
            String pathToReplace = entry.getKey().toString();
            if (contents.contains(pathToReplace)) {
                // String.replace creates a number of objects, and creates a fair
                // amount of object churn at this level, so we avoid doing it if
                // it's essentially going to be a no-op.
                contents = contents.replace(pathToReplace, replacement);
            }
        }
        return contents;
    }

    public String restore(Optional<Path> workingDir, String contents) {
        for (Map.Entry<Path, Path> entry : getAllPaths(workingDir).entrySet()) {
            contents = contents.replace(getExpandedPath(entry.getValue()), entry.getKey().toString());
        }
        return contents;
    }

    // Construct the replacer, giving the expanded current directory and the desired directory.
    // We use ASCII, since all the relevant debug standards we care about (e.g. DWARF) use it.
    abstract void restoreCompilationDirectory(Path path, Path workingDir) throws IOException;
}