Update from Google.

--
MOE_MIGRATED_REVID=85702957

1 files changed, 136 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java b/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java
new file mode 100644
index 0000000000..dd4375cfbf
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/vfs/AbstractFileSystem.java
@@ -0,0 +1,136 @@
+// Copyright 2014 Google Inc. 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.vfs;
+
+import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
+import com.google.devtools.build.lib.profiler.Profiler;
+import com.google.devtools.build.lib.profiler.ProfilerTask;
+import com.google.devtools.build.lib.unix.FileAccessException;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ * This class implements the FileSystem interface using direct calls to the
+ * UNIX filesystem.
+ */
+@ThreadSafe
+abstract class AbstractFileSystem extends FileSystem {
+
+  protected static final String ERR_PERMISSION_DENIED = " (Permission denied)";
+  protected static final Profiler profiler = Profiler.instance();
+
+  @Override
+  protected InputStream getInputStream(Path path) throws FileNotFoundException {
+    // This loop is a workaround for an apparent bug in FileInputStrean.open, which delegates
+    // ultimately to JVM_Open in the Hotspot JVM.  This call is not EINTR-safe, so we must do the
+    // retry here.
+    for (;;) {
+      try {
+        return createFileInputStream(path);
+      } catch (FileNotFoundException e) {
+        if (e.getMessage().endsWith("(Interrupted system call)")) {
+          continue;
+        } else {
+          throw e;
+        }
+      }
+    }
+  }
+
+  /**
+   * Returns either normal or profiled FileInputStream.
+   */
+  private InputStream createFileInputStream(Path path) throws FileNotFoundException {
+    final String name = path.toString();
+    if (profiler.isActive() && (profiler.isProfiling(ProfilerTask.VFS_READ) ||
+        profiler.isProfiling(ProfilerTask.VFS_OPEN))) {
+      long startTime = Profiler.nanoTimeMaybe();
+      try {
+        // Replace default FileInputStream instance with the custom one that does profiling.
+        return new FileInputStream(name) {
+          @Override public int read(byte b[]) throws IOException {
+            return read(b, 0, b.length);
+          }
+          @Override public int read(byte b[], int off, int len) throws IOException {
+            long startTime = Profiler.nanoTimeMaybe();
+            try {
+              return super.read(b, off, len);
+            } finally {
+              profiler.logSimpleTask(startTime, ProfilerTask.VFS_READ, name);
+            }
+          }
+        };
+      } finally {
+        profiler.logSimpleTask(startTime, ProfilerTask.VFS_OPEN, name);
+      }
+    } else {
+      // Use normal FileInputStream instance if profiler is not enabled.
+      return new FileInputStream(path.toString());
+    }
+  }
+
+  /**
+   * Returns either normal or profiled FileOutputStream. Should be used by subclasses
+   * to create default OutputStream instance.
+   */
+  protected OutputStream createFileOutputStream(Path path, boolean append)
+      throws FileNotFoundException {
+    final String name = path.toString();
+    if (profiler.isActive() && (profiler.isProfiling(ProfilerTask.VFS_WRITE) ||
+        profiler.isProfiling(ProfilerTask.VFS_OPEN))) {
+      long startTime = Profiler.nanoTimeMaybe();
+      try {
+        return new FileOutputStream(name, append) {
+          @Override public void write(byte b[]) throws IOException {
+            write(b, 0, b.length);
+          }
+          @Override public void write(byte b[], int off, int len) throws IOException {
+            long startTime = Profiler.nanoTimeMaybe();
+            try {
+              super.write(b, off, len);
+            } finally {
+              profiler.logSimpleTask(startTime, ProfilerTask.VFS_WRITE, name);
+            }
+          }
+        };
+      } finally {
+        profiler.logSimpleTask(startTime, ProfilerTask.VFS_OPEN, name);
+      }
+    } else {
+      return new FileOutputStream(name, append);
+    }
+  }
+
+  @Override
+  protected OutputStream getOutputStream(Path path, boolean append) throws IOException {
+    synchronized (path) {
+      try {
+        return createFileOutputStream(path, append);
+      } catch (FileNotFoundException e) {
+        // Why does it throw a *FileNotFoundException* if it can't write?
+        // That does not make any sense! And its in a completely different
+        // format than in other situations, no less!
+        if (e.getMessage().equals(path + ERR_PERMISSION_DENIED)) {
+          throw new FileAccessException(e.getMessage());
+        }
+        throw e;
+      }
+    }
+  }
+}