Home | History | Annotate | Download | only in internal
      1 // Protocol Buffers - Google's data interchange format
      2 // Copyright 2008 Google Inc.  All rights reserved.
      3 // https://developers.google.com/protocol-buffers/
      4 //
      5 // Redistribution and use in source and binary forms, with or without
      6 // modification, are permitted provided that the following conditions are
      7 // met:
      8 //
      9 //     * Redistributions of source code must retain the above copyright
     10 // notice, this list of conditions and the following disclaimer.
     11 //     * Redistributions in binary form must reproduce the above
     12 // copyright notice, this list of conditions and the following disclaimer
     13 // in the documentation and/or other materials provided with the
     14 // distribution.
     15 //     * Neither the name of Google Inc. nor the names of its
     16 // contributors may be used to endorse or promote products derived from
     17 // this software without specific prior written permission.
     18 //
     19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     30 
     31 #ifndef GOOGLE_PROTOBUF_UTIL_CONVERTER_DATAPIECE_H__
     32 #define GOOGLE_PROTOBUF_UTIL_CONVERTER_DATAPIECE_H__
     33 
     34 #include <string>
     35 
     36 #include <google/protobuf/stubs/common.h>
     37 #include <google/protobuf/stubs/stringpiece.h>
     38 #include <google/protobuf/stubs/statusor.h>
     39 
     40 
     41 namespace google {
     42 namespace protobuf {
     43 class Enum;
     44 }  // namespace protobuf
     45 
     46 
     47 namespace protobuf {
     48 namespace util {
     49 namespace converter {
     50 
     51 // Container for a single piece of data together with its data type.
     52 //
     53 // For primitive types (int32, int64, uint32, uint64, double, float, bool),
     54 // the data is stored by value.
     55 //
     56 // For string, a StringPiece is stored. For Cord, a pointer to Cord is stored.
     57 // Just like StringPiece, the DataPiece class does not own the storage for
     58 // the actual string or Cord, so it is the user's responsiblity to guarantee
     59 // that the underlying storage is still valid when the DataPiece is accessed.
     60 class LIBPROTOBUF_EXPORT DataPiece {
     61  public:
     62   // Identifies data type of the value.
     63   // These are the types supported by DataPiece.
     64   enum Type {
     65     TYPE_INT32 = 1,
     66     TYPE_INT64 = 2,
     67     TYPE_UINT32 = 3,
     68     TYPE_UINT64 = 4,
     69     TYPE_DOUBLE = 5,
     70     TYPE_FLOAT = 6,
     71     TYPE_BOOL = 7,
     72     TYPE_ENUM = 8,
     73     TYPE_STRING = 9,
     74     TYPE_BYTES = 10,
     75     TYPE_NULL = 11,  // explicit NULL type
     76   };
     77 
     78   // Constructors and Destructor
     79   explicit DataPiece(const int32 value) : type_(TYPE_INT32), i32_(value) {}
     80   explicit DataPiece(const int64 value) : type_(TYPE_INT64), i64_(value) {}
     81   explicit DataPiece(const uint32 value) : type_(TYPE_UINT32), u32_(value) {}
     82   explicit DataPiece(const uint64 value) : type_(TYPE_UINT64), u64_(value) {}
     83   explicit DataPiece(const double value) : type_(TYPE_DOUBLE), double_(value) {}
     84   explicit DataPiece(const float value) : type_(TYPE_FLOAT), float_(value) {}
     85   explicit DataPiece(const bool value) : type_(TYPE_BOOL), bool_(value) {}
     86   DataPiece(StringPiece value, bool use_strict_base64_decoding)
     87       : type_(TYPE_STRING),
     88         str_(StringPiecePod::CreateFromStringPiece(value)),
     89         use_strict_base64_decoding_(use_strict_base64_decoding) {}
     90   // Constructor for bytes. The second parameter is not used.
     91   DataPiece(StringPiece value, bool dummy, bool use_strict_base64_decoding)
     92       : type_(TYPE_BYTES),
     93         str_(StringPiecePod::CreateFromStringPiece(value)),
     94         use_strict_base64_decoding_(use_strict_base64_decoding) {}
     95   DataPiece(const DataPiece& r) : type_(r.type_), str_(r.str_) {}
     96   DataPiece& operator=(const DataPiece& x) {
     97     type_ = x.type_;
     98     str_ = x.str_;
     99     return *this;
    100   }
    101 
    102   static DataPiece NullData() { return DataPiece(TYPE_NULL, 0); }
    103 
    104   virtual ~DataPiece() {
    105   }
    106 
    107   // Accessors
    108   Type type() const { return type_; }
    109 
    110   StringPiece str() const {
    111     GOOGLE_LOG_IF(DFATAL, type_ != TYPE_STRING) << "Not a string type.";
    112     return str_;
    113   }
    114 
    115 
    116   // Parses, casts or converts the value stored in the DataPiece into an int32.
    117   util::StatusOr<int32> ToInt32() const;
    118 
    119   // Parses, casts or converts the value stored in the DataPiece into a uint32.
    120   util::StatusOr<uint32> ToUint32() const;
    121 
    122   // Parses, casts or converts the value stored in the DataPiece into an int64.
    123   util::StatusOr<int64> ToInt64() const;
    124 
    125   // Parses, casts or converts the value stored in the DataPiece into a uint64.
    126   util::StatusOr<uint64> ToUint64() const;
    127 
    128   // Parses, casts or converts the value stored in the DataPiece into a double.
    129   util::StatusOr<double> ToDouble() const;
    130 
    131   // Parses, casts or converts the value stored in the DataPiece into a float.
    132   util::StatusOr<float> ToFloat() const;
    133 
    134   // Parses, casts or converts the value stored in the DataPiece into a bool.
    135   util::StatusOr<bool> ToBool() const;
    136 
    137   // Parses, casts or converts the value stored in the DataPiece into a string.
    138   util::StatusOr<string> ToString() const;
    139 
    140   // Tries to convert the value contained in this datapiece to string. If the
    141   // conversion fails, it returns the default_string.
    142   string ValueAsStringOrDefault(StringPiece default_string) const;
    143 
    144   util::StatusOr<string> ToBytes() const;
    145 
    146   // Converts a value into protocol buffer enum number. If the value is a
    147   // string, first attempts conversion by name, trying names as follows:
    148   //   1) the directly provided string value.
    149   //   2) the value upper-cased and replacing '-' by '_'
    150   // If the value is not a string, attempts to convert to a 32-bit integer.
    151   // If none of these succeeds, returns a conversion error status.
    152   util::StatusOr<int> ToEnum(const google::protobuf::Enum* enum_type) const;
    153 
    154  private:
    155   // Disallow implicit constructor.
    156   DataPiece();
    157 
    158   // Helper to create NULL or ENUM types.
    159   DataPiece(Type type, int32 val) : type_(type), i32_(val) {}
    160 
    161   // For numeric conversion between
    162   //     int32, int64, uint32, uint64, double, float and bool
    163   template <typename To>
    164   util::StatusOr<To> GenericConvert() const;
    165 
    166   // For conversion from string to
    167   //     int32, int64, uint32, uint64, double, float and bool
    168   template <typename To>
    169   util::StatusOr<To> StringToNumber(bool (*func)(StringPiece, To*)) const;
    170 
    171   // Decodes a base64 string. Returns true on success.
    172   bool DecodeBase64(StringPiece src, string* dest) const;
    173 
    174   // Data type for this piece of data.
    175   Type type_;
    176 
    177   typedef ::google::protobuf::internal::StringPiecePod StringPiecePod;
    178 
    179   // Stored piece of data.
    180   union {
    181     int32 i32_;
    182     int64 i64_;
    183     uint32 u32_;
    184     uint64 u64_;
    185     double double_;
    186     float float_;
    187     bool bool_;
    188     StringPiecePod str_;
    189   };
    190 
    191   // Uses a stricter version of base64 decoding for byte fields.
    192   bool use_strict_base64_decoding_;
    193 };
    194 
    195 }  // namespace converter
    196 }  // namespace util
    197 }  // namespace protobuf
    198 
    199 }  // namespace google
    200 #endif  // GOOGLE_PROTOBUF_UTIL_CONVERTER_DATAPIECE_H__
    201