reverting disastrous MOE commit, returning to r21

git-svn-id: https://leveldb.googlecode.com/svn/trunk@23 62dab493-f737-651d-591e-8d6aee1b9529

1 files changed, 86 insertions, 0 deletions

diff --git a/include/leveldb/status.h b/include/leveldb/status.h
new file mode 100644
index 0000000..47e3edf
--- /dev/null
+++ b/include/leveldb/status.h
@@ -0,0 +1,86 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// A Status encapsulates the result of an operation.  It may indicate success,
+// or it may indicate an error with an associated error message.
+
+#ifndef STORAGE_LEVELDB_INCLUDE_STATUS_H_
+#define STORAGE_LEVELDB_INCLUDE_STATUS_H_
+
+#include <string>
+#include <utility>
+#include "leveldb/slice.h"
+
+namespace leveldb {
+
+class Status {
+ public:
+  // Create a success status.
+  Status() : state_(NULL) { }
+  ~Status() { delete state_; }
+
+  // Copy the specified status.
+  Status(const Status& s);
+  void operator=(const Status& s);
+
+  // Return a success status.
+  static Status OK() { return Status(); }
+
+  // Return error status of an appropriate type.
+  static Status NotFound(const Slice& msg, const Slice& msg2 = Slice()) {
+    return Status(kNotFound, msg, Slice());
+  }
+  static Status Corruption(const Slice& msg, const Slice& msg2 = Slice()) {
+    return Status(kCorruption, msg, msg2);
+  }
+  static Status NotSupported(const Slice& msg, const Slice& msg2 = Slice()) {
+    return Status(kNotSupported, msg, msg2);
+  }
+  static Status InvalidArgument(const Slice& msg, const Slice& msg2 = Slice()) {
+    return Status(kInvalidArgument, msg, msg2);
+  }
+  static Status IOError(const Slice& msg, const Slice& msg2 = Slice()) {
+    return Status(kIOError, msg, msg2);
+  }
+
+  // Returns true iff the status indicates success.
+  bool ok() const { return (state_ == NULL); }
+
+  // Returns true iff the status indicates a NotFound error.
+  bool IsNotFound() const { return code() == kNotFound; }
+
+  // Return a string representation of this status suitable for printing.
+  // Returns the string "OK" for success.
+  std::string ToString() const;
+
+ private:
+  enum Code {
+    kOk = 0,
+    kNotFound = 1,
+    kCorruption = 2,
+    kNotSupported = 3,
+    kInvalidArgument = 4,
+    kIOError = 5,
+  };
+  Code code() const { return (state_ == NULL) ? kOk : state_->first; }
+
+  Status(Code code, const Slice& msg, const Slice& msg2);
+
+  typedef std::pair<Code, std::string> State;
+  State* state_;
+};
+
+inline Status::Status(const Status& s) {
+  state_ = (s.state_ == NULL) ? NULL : new State(*s.state_);
+}
+inline void Status::operator=(const Status& s) {
+  if (this != &s) {
+    delete state_;
+    state_ = (s.state_ == NULL) ? NULL : new State(*s.state_);
+  }
+}
+
+}
+
+#endif  // STORAGE_LEVELDB_INCLUDE_STATUS_H_