Rewrite all the sandbox strategy implementations

- Make use of existing abstractions like SpawnRunner and SpawnExecutionPolicy.
- Instead of having the *Strategy create a *Runner, and then call back into
  SandboxStrategy, create a single SandboxContainer which contains the full
  command line, environment, and everything needed to create and delete the
  sandbox directory.
- Do all the work in SandboxStrategy, including creation and deletion of the
  sandbox directory.
- Use SpawnResult instead of throwing, catching, and rethrowing.
- Simplify the control flow a bit.

PiperOrigin-RevId: 161644979

1 files changed, 0 insertions, 160 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/sandbox/SymlinkedExecRoot.java b/src/main/java/com/google/devtools/build/lib/sandbox/SymlinkedExecRoot.java
deleted file mode 100644
index a158f02961..0000000000
--- a/src/main/java/com/google/devtools/build/lib/sandbox/SymlinkedExecRoot.java
+++ /dev/null
@@ -1,160 +0,0 @@
-// Copyright 2016 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.lib.sandbox;
-
-import com.google.common.io.Files;
-import com.google.devtools.build.lib.util.Preconditions;
-import com.google.devtools.build.lib.vfs.FileStatus;
-import com.google.devtools.build.lib.vfs.FileSystemUtils;
-import com.google.devtools.build.lib.vfs.Path;
-import com.google.devtools.build.lib.vfs.PathFragment;
-import com.google.devtools.build.lib.vfs.Symlinks;
-import java.io.IOException;
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Set;
-
-/**
- * Creates an execRoot for a Spawn that contains input files as symlinks to their original
- * destination.
- */
-public final class SymlinkedExecRoot implements SandboxExecRoot {
-
-  private final Path sandboxExecRoot;
-
-  public SymlinkedExecRoot(Path sandboxExecRoot) {
-    this.sandboxExecRoot = sandboxExecRoot;
-  }
-
-  @Override
-  public void createFileSystem(
-      Map<PathFragment, Path> inputs, Collection<PathFragment> outputs, Set<Path> writableDirs)
-      throws IOException {
-    Set<Path> createdDirs = new HashSet<>();
-    cleanFileSystem(inputs.keySet());
-    FileSystemUtils.createDirectoryAndParentsWithCache(createdDirs, sandboxExecRoot);
-    createParentDirectoriesForInputs(createdDirs, inputs.keySet());
-    createInputs(inputs);
-    createWritableDirectories(createdDirs, writableDirs);
-    createDirectoriesForOutputs(createdDirs, outputs);
-  }
-
-  private void cleanFileSystem(Set<PathFragment> allowedFiles) throws IOException {
-    if (sandboxExecRoot.exists(Symlinks.NOFOLLOW)) {
-      deleteExceptAllowedFiles(sandboxExecRoot, allowedFiles);
-    }
-  }
-
-  private void deleteExceptAllowedFiles(Path root, Set<PathFragment> allowedFiles)
-      throws IOException {
-    for (Path p : root.getDirectoryEntries()) {
-      FileStatus stat = p.stat(Symlinks.NOFOLLOW);
-      if (!stat.isDirectory()) {
-        if (!allowedFiles.contains(p.relativeTo(sandboxExecRoot))) {
-          p.delete();
-        }
-      } else {
-        deleteExceptAllowedFiles(p, allowedFiles);
-        if (p.readdir(Symlinks.NOFOLLOW).isEmpty()) {
-          p.delete();
-        }
-      }
-    }
-  }
-
-  /**
-   * No input can be a child of another input, because otherwise we might try to create a symlink
-   * below another symlink we created earlier - which means we'd actually end up writing somewhere
-   * in the workspace.
-   *
-   * <p>If all inputs were regular files, this situation could naturally not happen - but
-   * unfortunately, we might get the occasional action that has directories in its inputs.
-   *
-   * <p>Creating all parent directories first ensures that we can safely create symlinks to
-   * directories, too, because we'll get an IOException with EEXIST if inputs happen to be nested
-   * once we start creating the symlinks for all inputs.
-   */
-  private void createParentDirectoriesForInputs(Set<Path> createdDirs, Set<PathFragment> inputs)
-      throws IOException {
-    for (PathFragment inputPath : inputs) {
-      Path dir = sandboxExecRoot.getRelative(inputPath).getParentDirectory();
-      Preconditions.checkArgument(
-          dir.startsWith(sandboxExecRoot), "Bad relative path: '%s'", inputPath);
-      FileSystemUtils.createDirectoryAndParentsWithCache(createdDirs, dir);
-    }
-  }
-
-  private void createInputs(Map<PathFragment, Path> inputs) throws IOException {
-    // All input files are relative to the execroot.
-    for (Entry<PathFragment, Path> entry : inputs.entrySet()) {
-      Path key = sandboxExecRoot.getRelative(entry.getKey());
-      FileStatus keyStat = key.statNullable(Symlinks.NOFOLLOW);
-      if (keyStat != null) {
-        if (keyStat.isSymbolicLink()
-            && entry.getValue() != null
-            && key.readSymbolicLink().equals(entry.getValue().asFragment())) {
-          continue;
-        }
-        key.delete();
-      }
-      // A null value means that we're supposed to create an empty file as the input.
-      if (entry.getValue() != null) {
-        key.createSymbolicLink(entry.getValue());
-      } else {
-        FileSystemUtils.createEmptyFile(key);
-      }
-    }
-  }
-
-  private void createWritableDirectories(Set<Path> createdDirs, Set<Path> writableDirs)
-      throws IOException {
-    for (Path writablePath : writableDirs) {
-      if (writablePath.startsWith(sandboxExecRoot)) {
-        FileSystemUtils.createDirectoryAndParentsWithCache(createdDirs, writablePath);
-      }
-    }
-  }
-
-  /** Prepare the output directories in the sandbox. */
-  private void createDirectoriesForOutputs(Set<Path> createdDirs, Collection<PathFragment> outputs)
-      throws IOException {
-    for (PathFragment output : outputs) {
-      FileSystemUtils.createDirectoryAndParentsWithCache(
-          createdDirs, sandboxExecRoot.getRelative(output.getParentDirectory()));
-    }
-  }
-
-  /** Moves all {@code outputs} to {@code execRoot}. */
-  @Override
-  public void copyOutputs(Path execRoot, Collection<PathFragment> outputs) throws IOException {
-    for (PathFragment output : outputs) {
-      Path source = sandboxExecRoot.getRelative(output);
-      Path target = execRoot.getRelative(output);
-      if (source.isFile() || source.isSymbolicLink()) {
-        Files.move(source.getPathFile(), target.getPathFile());
-      } else if (source.isDirectory()) {
-        try {
-          source.renameTo(target);
-        } catch (IOException e) {
-          // Failed to move directory directly, thus move it recursively.
-          target.createDirectory();
-          FileSystemUtils.moveTreesBelow(source, target);
-        }
-      }
-    }
-  }
-}