1 #region Copyright notice and license 2 // Protocol Buffers - Google's data interchange format 3 // Copyright 2008 Google Inc. All rights reserved. 4 // https://developers.google.com/protocol-buffers/ 5 // 6 // Redistribution and use in source and binary forms, with or without 7 // modification, are permitted provided that the following conditions are 8 // met: 9 // 10 // * Redistributions of source code must retain the above copyright 11 // notice, this list of conditions and the following disclaimer. 12 // * Redistributions in binary form must reproduce the above 13 // copyright notice, this list of conditions and the following disclaimer 14 // in the documentation and/or other materials provided with the 15 // distribution. 16 // * Neither the name of Google Inc. nor the names of its 17 // contributors may be used to endorse or promote products derived from 18 // this software without specific prior written permission. 19 // 20 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 23 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 24 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 25 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 26 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 30 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 #endregion 32 33 using System; 34 35 namespace Google.Protobuf 36 { 37 // This part of CodedOutputStream provides all the static entry points that are used 38 // by generated code and internally to compute the size of messages prior to being 39 // written to an instance of CodedOutputStream. 40 public sealed partial class CodedOutputStream 41 { 42 private const int LittleEndian64Size = 8; 43 private const int LittleEndian32Size = 4; 44 45 internal const int DoubleSize = LittleEndian64Size; 46 internal const int FloatSize = LittleEndian32Size; 47 internal const int BoolSize = 1; 48 49 /// <summary> 50 /// Computes the number of bytes that would be needed to encode a 51 /// double field, including the tag. 52 /// </summary> ComputeDoubleSize(double value)53 public static int ComputeDoubleSize(double value) 54 { 55 return DoubleSize; 56 } 57 58 /// <summary> 59 /// Computes the number of bytes that would be needed to encode a 60 /// float field, including the tag. 61 /// </summary> ComputeFloatSize(float value)62 public static int ComputeFloatSize(float value) 63 { 64 return FloatSize; 65 } 66 67 /// <summary> 68 /// Computes the number of bytes that would be needed to encode a 69 /// uint64 field, including the tag. 70 /// </summary> ComputeUInt64Size(ulong value)71 public static int ComputeUInt64Size(ulong value) 72 { 73 return ComputeRawVarint64Size(value); 74 } 75 76 /// <summary> 77 /// Computes the number of bytes that would be needed to encode an 78 /// int64 field, including the tag. 79 /// </summary> ComputeInt64Size(long value)80 public static int ComputeInt64Size(long value) 81 { 82 return ComputeRawVarint64Size((ulong) value); 83 } 84 85 /// <summary> 86 /// Computes the number of bytes that would be needed to encode an 87 /// int32 field, including the tag. 88 /// </summary> ComputeInt32Size(int value)89 public static int ComputeInt32Size(int value) 90 { 91 if (value >= 0) 92 { 93 return ComputeRawVarint32Size((uint) value); 94 } 95 else 96 { 97 // Must sign-extend. 98 return 10; 99 } 100 } 101 102 /// <summary> 103 /// Computes the number of bytes that would be needed to encode a 104 /// fixed64 field, including the tag. 105 /// </summary> ComputeFixed64Size(ulong value)106 public static int ComputeFixed64Size(ulong value) 107 { 108 return LittleEndian64Size; 109 } 110 111 /// <summary> 112 /// Computes the number of bytes that would be needed to encode a 113 /// fixed32 field, including the tag. 114 /// </summary> ComputeFixed32Size(uint value)115 public static int ComputeFixed32Size(uint value) 116 { 117 return LittleEndian32Size; 118 } 119 120 /// <summary> 121 /// Computes the number of bytes that would be needed to encode a 122 /// bool field, including the tag. 123 /// </summary> ComputeBoolSize(bool value)124 public static int ComputeBoolSize(bool value) 125 { 126 return BoolSize; 127 } 128 129 /// <summary> 130 /// Computes the number of bytes that would be needed to encode a 131 /// string field, including the tag. 132 /// </summary> ComputeStringSize(String value)133 public static int ComputeStringSize(String value) 134 { 135 int byteArraySize = Utf8Encoding.GetByteCount(value); 136 return ComputeLengthSize(byteArraySize) + byteArraySize; 137 } 138 139 /// <summary> 140 /// Computes the number of bytes that would be needed to encode a 141 /// group field, including the tag. 142 /// </summary> ComputeGroupSize(IMessage value)143 public static int ComputeGroupSize(IMessage value) 144 { 145 return value.CalculateSize(); 146 } 147 148 /// <summary> 149 /// Computes the number of bytes that would be needed to encode an 150 /// embedded message field, including the tag. 151 /// </summary> ComputeMessageSize(IMessage value)152 public static int ComputeMessageSize(IMessage value) 153 { 154 int size = value.CalculateSize(); 155 return ComputeLengthSize(size) + size; 156 } 157 158 /// <summary> 159 /// Computes the number of bytes that would be needed to encode a 160 /// bytes field, including the tag. 161 /// </summary> ComputeBytesSize(ByteString value)162 public static int ComputeBytesSize(ByteString value) 163 { 164 return ComputeLengthSize(value.Length) + value.Length; 165 } 166 167 /// <summary> 168 /// Computes the number of bytes that would be needed to encode a 169 /// uint32 field, including the tag. 170 /// </summary> ComputeUInt32Size(uint value)171 public static int ComputeUInt32Size(uint value) 172 { 173 return ComputeRawVarint32Size(value); 174 } 175 176 /// <summary> 177 /// Computes the number of bytes that would be needed to encode a 178 /// enum field, including the tag. The caller is responsible for 179 /// converting the enum value to its numeric value. 180 /// </summary> ComputeEnumSize(int value)181 public static int ComputeEnumSize(int value) 182 { 183 // Currently just a pass-through, but it's nice to separate it logically. 184 return ComputeInt32Size(value); 185 } 186 187 /// <summary> 188 /// Computes the number of bytes that would be needed to encode an 189 /// sfixed32 field, including the tag. 190 /// </summary> ComputeSFixed32Size(int value)191 public static int ComputeSFixed32Size(int value) 192 { 193 return LittleEndian32Size; 194 } 195 196 /// <summary> 197 /// Computes the number of bytes that would be needed to encode an 198 /// sfixed64 field, including the tag. 199 /// </summary> ComputeSFixed64Size(long value)200 public static int ComputeSFixed64Size(long value) 201 { 202 return LittleEndian64Size; 203 } 204 205 /// <summary> 206 /// Computes the number of bytes that would be needed to encode an 207 /// sint32 field, including the tag. 208 /// </summary> ComputeSInt32Size(int value)209 public static int ComputeSInt32Size(int value) 210 { 211 return ComputeRawVarint32Size(EncodeZigZag32(value)); 212 } 213 214 /// <summary> 215 /// Computes the number of bytes that would be needed to encode an 216 /// sint64 field, including the tag. 217 /// </summary> ComputeSInt64Size(long value)218 public static int ComputeSInt64Size(long value) 219 { 220 return ComputeRawVarint64Size(EncodeZigZag64(value)); 221 } 222 223 /// <summary> 224 /// Computes the number of bytes that would be needed to encode a length, 225 /// as written by <see cref="WriteLength"/>. 226 /// </summary> ComputeLengthSize(int length)227 public static int ComputeLengthSize(int length) 228 { 229 return ComputeRawVarint32Size((uint) length); 230 } 231 232 /// <summary> 233 /// Computes the number of bytes that would be needed to encode a varint. 234 /// </summary> ComputeRawVarint32Size(uint value)235 public static int ComputeRawVarint32Size(uint value) 236 { 237 if ((value & (0xffffffff << 7)) == 0) 238 { 239 return 1; 240 } 241 if ((value & (0xffffffff << 14)) == 0) 242 { 243 return 2; 244 } 245 if ((value & (0xffffffff << 21)) == 0) 246 { 247 return 3; 248 } 249 if ((value & (0xffffffff << 28)) == 0) 250 { 251 return 4; 252 } 253 return 5; 254 } 255 256 /// <summary> 257 /// Computes the number of bytes that would be needed to encode a varint. 258 /// </summary> ComputeRawVarint64Size(ulong value)259 public static int ComputeRawVarint64Size(ulong value) 260 { 261 if ((value & (0xffffffffffffffffL << 7)) == 0) 262 { 263 return 1; 264 } 265 if ((value & (0xffffffffffffffffL << 14)) == 0) 266 { 267 return 2; 268 } 269 if ((value & (0xffffffffffffffffL << 21)) == 0) 270 { 271 return 3; 272 } 273 if ((value & (0xffffffffffffffffL << 28)) == 0) 274 { 275 return 4; 276 } 277 if ((value & (0xffffffffffffffffL << 35)) == 0) 278 { 279 return 5; 280 } 281 if ((value & (0xffffffffffffffffL << 42)) == 0) 282 { 283 return 6; 284 } 285 if ((value & (0xffffffffffffffffL << 49)) == 0) 286 { 287 return 7; 288 } 289 if ((value & (0xffffffffffffffffL << 56)) == 0) 290 { 291 return 8; 292 } 293 if ((value & (0xffffffffffffffffL << 63)) == 0) 294 { 295 return 9; 296 } 297 return 10; 298 } 299 300 /// <summary> 301 /// Computes the number of bytes that would be needed to encode a tag. 302 /// </summary> ComputeTagSize(int fieldNumber)303 public static int ComputeTagSize(int fieldNumber) 304 { 305 return ComputeRawVarint32Size(WireFormat.MakeTag(fieldNumber, 0)); 306 } 307 } 308 }