acl/include/google/protobuf/wire_format.h

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// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// http://code.google.com/p/protobuf/
//
// 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.
// Author: kenton@google.com (Kenton Varda)
// atenasio@google.com (Chris Atenasio) (ZigZag transform)
// Based on original Protocol Buffers design by
// Sanjay Ghemawat, Jeff Dean, and others.
//
// This header is logically internal, but is made public because it is used
// from protocol-compiler-generated code, which may reside in other components.
#ifndef GOOGLE_PROTOBUF_WIRE_FORMAT_H__
#define GOOGLE_PROTOBUF_WIRE_FORMAT_H__
#include <string>
#include <google/protobuf/stubs/common.h>
#include <google/protobuf/descriptor.pb.h>
#include <google/protobuf/descriptor.h>
#include <google/protobuf/message.h>
#include <google/protobuf/wire_format_lite.h>
// Do UTF-8 validation on string type in Debug build only
#ifndef NDEBUG
#define GOOGLE_PROTOBUF_UTF8_VALIDATION_ENABLED
#endif
namespace google {
namespace protobuf {
namespace io {
class CodedInputStream; // coded_stream.h
class CodedOutputStream; // coded_stream.h
}
class UnknownFieldSet; // unknown_field_set.h
}
namespace protobuf {
namespace internal {
// This class is for internal use by the protocol buffer library and by
// protocol-complier-generated message classes. It must not be called
// directly by clients.
//
// This class contains code for implementing the binary protocol buffer
// wire format via reflection. The WireFormatLite class implements the
// non-reflection based routines.
//
// This class is really a namespace that contains only static methods
class LIBPROTOBUF_EXPORT WireFormat {
public:
// Given a field return its WireType
static inline WireFormatLite::WireType WireTypeForField(
const FieldDescriptor* field);
// Given a FieldSescriptor::Type return its WireType
static inline WireFormatLite::WireType WireTypeForFieldType(
FieldDescriptor::Type type);
// Compute the byte size of a tag. For groups, this includes both the start
// and end tags.
static inline int TagSize(int field_number, FieldDescriptor::Type type);
// These procedures can be used to implement the methods of Message which
// handle parsing and serialization of the protocol buffer wire format
// using only the Reflection interface. When you ask the protocol
// compiler to optimize for code size rather than speed, it will implement
// those methods in terms of these procedures. Of course, these are much
// slower than the specialized implementations which the protocol compiler
// generates when told to optimize for speed.
// Read a message in protocol buffer wire format.
//
// This procedure reads either to the end of the input stream or through
// a WIRETYPE_END_GROUP tag ending the message, whichever comes first.
// It returns false if the input is invalid.
//
// Required fields are NOT checked by this method. You must call
// IsInitialized() on the resulting message yourself.
static bool ParseAndMergePartial(io::CodedInputStream* input,
Message* message);
// Serialize a message in protocol buffer wire format.
//
// Any embedded messages within the message must have their correct sizes
// cached. However, the top-level message need not; its size is passed as
// a parameter to this procedure.
//
// These return false iff the underlying stream returns a write error.
static void SerializeWithCachedSizes(
const Message& message,
int size, io::CodedOutputStream* output);
// Implements Message::ByteSize() via reflection. WARNING: The result
// of this method is *not* cached anywhere. However, all embedded messages
// will have their ByteSize() methods called, so their sizes will be cached.
// Therefore, calling this method is sufficient to allow you to call
// WireFormat::SerializeWithCachedSizes() on the same object.
static int ByteSize(const Message& message);
// -----------------------------------------------------------------
// Helpers for dealing with unknown fields
// Skips a field value of the given WireType. The input should start
// positioned immediately after the tag. If unknown_fields is non-NULL,
// the contents of the field will be added to it.
static bool SkipField(io::CodedInputStream* input, uint32 tag,
UnknownFieldSet* unknown_fields);
// Reads and ignores a message from the input. If unknown_fields is non-NULL,
// the contents will be added to it.
static bool SkipMessage(io::CodedInputStream* input,
UnknownFieldSet* unknown_fields);
// Write the contents of an UnknownFieldSet to the output.
static void SerializeUnknownFields(const UnknownFieldSet& unknown_fields,
io::CodedOutputStream* output);
// Same as above, except writing directly to the provided buffer.
// Requires that the buffer have sufficient capacity for
// ComputeUnknownFieldsSize(unknown_fields).
//
// Returns a pointer past the last written byte.
static uint8* SerializeUnknownFieldsToArray(
const UnknownFieldSet& unknown_fields,
uint8* target);
// Same thing except for messages that have the message_set_wire_format
// option.
static void SerializeUnknownMessageSetItems(
const UnknownFieldSet& unknown_fields,
io::CodedOutputStream* output);
// Same as above, except writing directly to the provided buffer.
// Requires that the buffer have sufficient capacity for
// ComputeUnknownMessageSetItemsSize(unknown_fields).
//
// Returns a pointer past the last written byte.
static uint8* SerializeUnknownMessageSetItemsToArray(
const UnknownFieldSet& unknown_fields,
uint8* target);
// Compute the size of the UnknownFieldSet on the wire.
static int ComputeUnknownFieldsSize(const UnknownFieldSet& unknown_fields);
// Same thing except for messages that have the message_set_wire_format
// option.
static int ComputeUnknownMessageSetItemsSize(
const UnknownFieldSet& unknown_fields);
// Helper functions for encoding and decoding tags. (Inlined below and in
// _inl.h)
//
// This is different from MakeTag(field->number(), field->type()) in the case
// of packed repeated fields.
static uint32 MakeTag(const FieldDescriptor* field);
// Parse a single field. The input should start out positioned immidately
// after the tag.
static bool ParseAndMergeField(
uint32 tag,
const FieldDescriptor* field, // May be NULL for unknown
Message* message,
io::CodedInputStream* input);
// Serialize a single field.
static void SerializeFieldWithCachedSizes(
const FieldDescriptor* field, // Cannot be NULL
const Message& message,
io::CodedOutputStream* output);
// Compute size of a single field. If the field is a message type, this
// will call ByteSize() for the embedded message, insuring that it caches
// its size.
static int FieldByteSize(
const FieldDescriptor* field, // Cannot be NULL
const Message& message);
// Parse/serialize a MessageSet::Item group. Used with messages that use
// opion message_set_wire_format = true.
static bool ParseAndMergeMessageSetItem(
io::CodedInputStream* input,
Message* message);
static void SerializeMessageSetItemWithCachedSizes(
const FieldDescriptor* field,
const Message& message,
io::CodedOutputStream* output);
static int MessageSetItemByteSize(
const FieldDescriptor* field,
const Message& message);
// Computes the byte size of a field, excluding tags. For packed fields, it
// only includes the size of the raw data, and not the size of the total
// length, but for other length-delimited types, the size of the length is
// included.
static int FieldDataOnlyByteSize(
const FieldDescriptor* field, // Cannot be NULL
const Message& message);
enum Operation {
PARSE,
SERIALIZE,
};
// Verifies that a string field is valid UTF8, logging an error if not.
static void VerifyUTF8String(const char* data, int size, Operation op);
private:
// Verifies that a string field is valid UTF8, logging an error if not.
static void VerifyUTF8StringFallback(
const char* data,
int size,
Operation op);
GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(WireFormat);
};
// Subclass of FieldSkipper which saves skipped fields to an UnknownFieldSet.
class LIBPROTOBUF_EXPORT UnknownFieldSetFieldSkipper : public FieldSkipper {
public:
UnknownFieldSetFieldSkipper(UnknownFieldSet* unknown_fields)
: unknown_fields_(unknown_fields) {}
virtual ~UnknownFieldSetFieldSkipper() {}
// implements FieldSkipper -----------------------------------------
virtual bool SkipField(io::CodedInputStream* input, uint32 tag);
virtual bool SkipMessage(io::CodedInputStream* input);
virtual void SkipUnknownEnum(int field_number, int value);
protected:
UnknownFieldSet* unknown_fields_;
};
// inline methods ====================================================
inline WireFormatLite::WireType WireFormat::WireTypeForField(
const FieldDescriptor* field) {
if (field->options().packed()) {
return WireFormatLite::WIRETYPE_LENGTH_DELIMITED;
} else {
return WireTypeForFieldType(field->type());
}
}
inline WireFormatLite::WireType WireFormat::WireTypeForFieldType(
FieldDescriptor::Type type) {
// Some compilers don't like enum -> enum casts, so we implicit_cast to
// int first.
return WireFormatLite::WireTypeForFieldType(
static_cast<WireFormatLite::FieldType>(
implicit_cast<int>(type)));
}
inline uint32 WireFormat::MakeTag(const FieldDescriptor* field) {
return WireFormatLite::MakeTag(field->number(), WireTypeForField(field));
}
inline int WireFormat::TagSize(int field_number, FieldDescriptor::Type type) {
// Some compilers don't like enum -> enum casts, so we implicit_cast to
// int first.
return WireFormatLite::TagSize(field_number,
static_cast<WireFormatLite::FieldType>(
implicit_cast<int>(type)));
}
inline void WireFormat::VerifyUTF8String(const char* data, int size,
WireFormat::Operation op) {
#ifdef GOOGLE_PROTOBUF_UTF8_VALIDATION_ENABLED
WireFormat::VerifyUTF8StringFallback(data, size, op);
#else
// Avoid the compiler warning about unsued variables.
(void)data; (void)size; (void)op;
#endif
}
} // namespace internal
} // namespace protobuf
} // namespace google
#endif // GOOGLE_PROTOBUF_WIRE_FORMAT_H__