Fix lifetime of leveldb::MojoEnv instances.

components/leveldb/env_mojo.h

Index: components/leveldb/env_mojo.h
diff --git a/components/leveldb/env_mojo.h b/components/leveldb/env_mojo.h
index d784803324321735652be12bd77c44540a4ae91b..12d1fd8f589c1a1432c20a2b6430b9d455922aa2 100644
--- a/components/leveldb/env_mojo.h
+++ b/components/leveldb/env_mojo.h
@@ -5,6 +5,7 @@
 #ifndef COMPONENTS_LEVELDB_ENV_MOJO_H_
 #define COMPONENTS_LEVELDB_ENV_MOJO_H_
 
+#include "base/id_map.h"
 #include "components/filesystem/public/interfaces/directory.mojom.h"
 #include "components/leveldb/leveldb_mojo_proxy.h"
 #include "third_party/leveldatabase/env_chromium.h"
@@ -19,10 +20,29 @@ namespace leveldb {
 // existence.
 class MojoEnv : public leveldb_env::ChromiumEnv {
  public:
-  MojoEnv(const std::string& name,
-          scoped_refptr<LevelDBMojoProxy> file_thread,
-          LevelDBMojoProxy::OpaqueDir* dir);
-  ~MojoEnv() override;
+  class Directory {
+   public:
+    ~Directory();
+    const std::string& prefix() const { return prefix_; }
+
+   private:
+    friend class MojoEnv;
+    Directory(MojoEnv* env, std::string prefix);
+    MojoEnv* env_;
+    std::string prefix_;
+  };
+
+  explicit MojoEnv(
+      scoped_refptr<base::SingleThreadTaskRunner> file_task_runner);
+
+  // Registers a |directory| with the leveldb environment, returning a string
+  // that should be used as prefix to indicate files in that directory.
+  std::unique_ptr<Directory> RegisterDirectory(
+      filesystem::mojom::DirectoryPtr directory);
+
+  base::SingleThreadTaskRunner* file_task_runner() const {
+    return thread_->task_runner();
+  }
 
   // Overridden from leveldb_env::EnvChromium:

[cmumford, 2017/04/12 23:06:39]

I know it was there before, but s/EnvChromium/ChromiumEnv/

   Status NewSequentialFile(const std::string& fname,
@@ -50,8 +70,15 @@ class MojoEnv : public leveldb_env::ChromiumEnv {
   // NowMicros() or SleepForMicroseconds() and use the EnvChromium versions.
 
  private:
+  ~MojoEnv() override;
+
+  void ParsePath(const std::string& path,
+                 LevelDBMojoProxy::OpaqueDir** out_dir,
+                 std::string* out_path);
+  void UnregisterDirectory(base::StringPiece prefix);
+
   scoped_refptr<LevelDBMojoProxy> thread_;
-  LevelDBMojoProxy::OpaqueDir* dir_;
+  IDMap<LevelDBMojoProxy::OpaqueDir*> dirs_;
 
   DISALLOW_COPY_AND_ASSIGN(MojoEnv);
 };