update code

include/google/protobuf/arenastring.h

@@ -0,0 +1,338 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef GOOGLE_PROTOBUF_ARENASTRING_H__
+#define GOOGLE_PROTOBUF_ARENASTRING_H__
+
+#include <string>
+
+#include <google/protobuf/arena.h>
+#include <google/protobuf/stubs/common.h>
+#include <google/protobuf/stubs/fastmem.h>
+#include <google/protobuf/stubs/logging.h>
+#include <google/protobuf/stubs/port.h>
+
+// This is the implementation of arena string fields written for the open-source
+// release. The ArenaStringPtr struct below is an internal implementation class
+// and *should not be used* by user code. It is used to collect string
+// operations together into one place and abstract away the underlying
+// string-field pointer representation, so that (for example) an alternate
+// implementation that knew more about ::std::string's internals could integrate more
+// closely with the arena allocator.
+
+namespace google {
+namespace protobuf {
+namespace internal {
+
+struct LIBPROTOBUF_EXPORT ArenaStringPtr {
+  inline void Set(const ::std::string* default_value,
+                  const ::std::string& value, ::google::protobuf::Arena* arena) {
+    if (ptr_ == default_value) {
+      CreateInstance(arena, &value);
+    } else {
+      *ptr_ = value;
+    }
+  }
+
+  inline void SetLite(const ::std::string* default_value,
+                      const ::std::string& value,
+                      ::google::protobuf::Arena* arena) {
+    Set(default_value, value, arena);
+  }
+
+  // Basic accessors.
+  inline const ::std::string& Get() const { return *ptr_; }
+
+  inline ::std::string* Mutable(const ::std::string* default_value,
+                           ::google::protobuf::Arena* arena) {
+    if (ptr_ == default_value) {
+      CreateInstance(arena, default_value);
+    }
+    return ptr_;
+  }
+
+  // Release returns a ::std::string* instance that is heap-allocated and is not
+  // Own()'d by any arena. If the field was not set, it returns NULL. The caller
+  // retains ownership. Clears this field back to NULL state. Used to implement
+  // release_<field>() methods on generated classes.
+  inline ::std::string* Release(const ::std::string* default_value,
+                           ::google::protobuf::Arena* arena) {
+    if (ptr_ == default_value) {
+      return NULL;
+    }
+    ::std::string* released = NULL;
+    if (arena != NULL) {
+      // ptr_ is owned by the arena.
+      released = new ::std::string;
+      released->swap(*ptr_);
+    } else {
+      released = ptr_;
+    }
+    ptr_ = const_cast< ::std::string* >(default_value);
+    return released;
+  }
+
+  // UnsafeArenaRelease returns a ::std::string*, but it may be arena-owned (i.e.
+  // have its destructor already registered) if arena != NULL. If the field was
+  // not set, this returns NULL. This method clears this field back to NULL
+  // state. Used to implement unsafe_arena_release_<field>() methods on
+  // generated classes.
+  inline ::std::string* UnsafeArenaRelease(const ::std::string* default_value,
+                                      ::google::protobuf::Arena* /* arena */) {
+    if (ptr_ == default_value) {
+      return NULL;
+    }
+    ::std::string* released = ptr_;
+    ptr_ = const_cast< ::std::string* >(default_value);
+    return released;
+  }
+
+  // Takes a string that is heap-allocated, and takes ownership. The string's
+  // destructor is registered with the arena. Used to implement
+  // set_allocated_<field> in generated classes.
+  inline void SetAllocated(const ::std::string* default_value,
+                           ::std::string* value, ::google::protobuf::Arena* arena) {
+    if (arena == NULL && ptr_ != default_value) {
+      Destroy(default_value, arena);
+    }
+    if (value != NULL) {
+      ptr_ = value;
+      if (arena != NULL) {
+        arena->Own(value);
+      }
+    } else {
+      ptr_ = const_cast< ::std::string* >(default_value);
+    }
+  }
+
+  // Takes a string that has lifetime equal to the arena's lifetime. The arena
+  // must be non-null. It is safe only to pass this method a value returned by
+  // UnsafeArenaRelease() on another field of a message in the same arena. Used
+  // to implement unsafe_arena_set_allocated_<field> in generated classes.
+  inline void UnsafeArenaSetAllocated(const ::std::string* default_value,
+                                      ::std::string* value,
+                                      ::google::protobuf::Arena* /* arena */) {
+    if (value != NULL) {
+      ptr_ = value;
+    } else {
+      ptr_ = const_cast< ::std::string* >(default_value);
+    }
+  }
+
+  // Swaps internal pointers. Arena-safety semantics: this is guarded by the
+  // logic in Swap()/UnsafeArenaSwap() at the message level, so this method is
+  // 'unsafe' if called directly.
+  GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE void Swap(ArenaStringPtr* other) {
+    std::swap(ptr_, other->ptr_);
+  }
+
+  // Frees storage (if not on an arena).
+  inline void Destroy(const ::std::string* default_value,
+                      ::google::protobuf::Arena* arena) {
+    if (arena == NULL && ptr_ != default_value) {
+      delete ptr_;
+    }
+  }
+
+  // Clears content, but keeps allocated string if arena != NULL, to avoid the
+  // overhead of heap operations. After this returns, the content (as seen by
+  // the user) will always be the empty string. Assumes that |default_value|
+  // is an empty string.
+  inline void ClearToEmpty(const ::std::string* default_value,
+                           ::google::protobuf::Arena* /* arena */) {
+    if (ptr_ == default_value) {
+      // Already set to default (which is empty) -- do nothing.
+    } else {
+      ptr_->clear();
+    }
+  }
+
+  // Clears content, but keeps allocated string if arena != NULL, to avoid the
+  // overhead of heap operations. After this returns, the content (as seen by
+  // the user) will always be equal to |default_value|.
+  inline void ClearToDefault(const ::std::string* default_value,
+                             ::google::protobuf::Arena* /* arena */) {
+    if (ptr_ == default_value) {
+      // Already set to default -- do nothing.
+    } else {
+      // Have another allocated string -- rather than throwing this away and
+      // resetting ptr_ to the canonical default string instance, we just reuse
+      // this instance.
+      *ptr_ = *default_value;
+    }
+  }
+
+  // Called from generated code / reflection runtime only. Resets value to point
+  // to a default string pointer, with the semantics that this ArenaStringPtr
+  // does not own the pointed-to memory. Disregards initial value of ptr_ (so
+  // this is the *ONLY* safe method to call after construction or when
+  // reinitializing after becoming the active field in a oneof union).
+  inline void UnsafeSetDefault(const ::std::string* default_value) {
+    // Casting away 'const' is safe here: accessors ensure that ptr_ is only
+    // returned as a const if it is equal to default_value.
+    ptr_ = const_cast< ::std::string* >(default_value);
+  }
+
+  // The 'NoArena' variants of methods below assume arena == NULL and are
+  // optimized to provide very little overhead relative to a raw string pointer
+  // (while still being in-memory compatible with other code that assumes
+  // ArenaStringPtr). Note the invariant that a class instance that has only
+  // ever been mutated by NoArena methods must *only* be in the String state
+  // (i.e., tag bits are not used), *NEVER* ArenaString. This allows all
+  // tagged-pointer manipulations to be avoided.
+  inline void SetNoArena(const ::std::string* default_value,
+                         const ::std::string& value) {
+    if (ptr_ == default_value) {
+      CreateInstanceNoArena(&value);
+    } else {
+      *ptr_ = value;
+    }
+  }
+
+#if LANG_CXX11
+  void SetNoArena(const ::std::string* default_value, ::std::string&& value) {
+    if (IsDefault(default_value)) {
+      ptr_ = new ::std::string(std::move(value));
+    } else {
+      *ptr_ = std::move(value);
+    }
+  }
+#endif
+
+  void AssignWithDefault(const ::std::string* default_value, ArenaStringPtr value);
+
+  inline const ::std::string& GetNoArena() const { return *ptr_; }
+
+  inline ::std::string* MutableNoArena(const ::std::string* default_value) {
+    if (ptr_ == default_value) {
+      CreateInstanceNoArena(default_value);
+    }
+    return ptr_;
+  }
+
+  inline ::std::string* ReleaseNoArena(const ::std::string* default_value) {
+    if (ptr_ == default_value) {
+      return NULL;
+    } else {
+      ::std::string* released = ptr_;
+      ptr_ = const_cast< ::std::string* >(default_value);
+      return released;
+    }
+  }
+
+  inline void SetAllocatedNoArena(const ::std::string* default_value,
+                                  ::std::string* value) {
+    if (ptr_ != default_value) {
+      delete ptr_;
+    }
+    if (value != NULL) {
+      ptr_ = value;
+    } else {
+      ptr_ = const_cast< ::std::string* >(default_value);
+    }
+  }
+
+  inline void DestroyNoArena(const ::std::string* default_value) {
+    if (ptr_ != default_value) {
+      delete ptr_;
+    }
+  }
+
+  inline void ClearToEmptyNoArena(const ::std::string* default_value) {
+    if (ptr_ == default_value) {
+      // Nothing: already equal to default (which is the empty string).
+    } else {
+      ptr_->clear();
+    }
+  }
+
+  inline void ClearToDefaultNoArena(const ::std::string* default_value) {
+    if (ptr_ == default_value) {
+      // Nothing: already set to default.
+    } else {
+      // Reuse existing allocated instance.
+      *ptr_ = *default_value;
+    }
+  }
+
+  // Internal accessor used only at parse time to provide direct access to the
+  // raw pointer from the shared parse routine (in the non-arenas case). The
+  // parse routine does the string allocation in order to save code size in the
+  // generated parsing code.
+  inline ::std::string** UnsafeRawStringPointer() {
+    return &ptr_;
+  }
+
+  inline bool IsDefault(const ::std::string* default_value) const {
+    return ptr_ == default_value;
+  }
+
+ private:
+  ::std::string* ptr_;
+
+  GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE
+  void CreateInstance(::google::protobuf::Arena* arena,
+                      const ::std::string* initial_value) {
+    GOOGLE_DCHECK(initial_value != NULL);
+    ptr_ = new ::std::string(*initial_value);
+    if (arena != NULL) {
+      arena->Own(ptr_);
+    }
+  }
+  GOOGLE_PROTOBUF_ATTRIBUTE_NOINLINE
+  void CreateInstanceNoArena(const ::std::string* initial_value) {
+    GOOGLE_DCHECK(initial_value != NULL);
+    ptr_ = new ::std::string(*initial_value);
+  }
+};
+
+}  // namespace internal
+}  // namespace protobuf
+
+
+
+namespace protobuf {
+namespace internal {
+
+inline void ArenaStringPtr::AssignWithDefault(const ::std::string* default_value,
+                                       ArenaStringPtr value) {
+  const ::std::string* me = *UnsafeRawStringPointer();
+  const ::std::string* other = *value.UnsafeRawStringPointer();
+  // If the pointers are the same then do nothing.
+  if (me != other) {
+    SetNoArena(default_value, value.GetNoArena());
+  }
+}
+
+}  // namespace internal
+}  // namespace protobuf
+
+}  // namespace google
+#endif  // GOOGLE_PROTOBUF_ARENASTRING_H__