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 /// <summary> 46 /// Computes the number of bytes that would be needed to encode a 47 /// double field, including the tag. 48 /// </summary> ComputeDoubleSize(double value)49 public static int ComputeDoubleSize(double value) 50 { 51 return LittleEndian64Size; 52 } 53 54 /// <summary> 55 /// Computes the number of bytes that would be needed to encode a 56 /// float field, including the tag. 57 /// </summary> ComputeFloatSize(float value)58 public static int ComputeFloatSize(float value) 59 { 60 return LittleEndian32Size; 61 } 62 63 /// <summary> 64 /// Computes the number of bytes that would be needed to encode a 65 /// uint64 field, including the tag. 66 /// </summary> ComputeUInt64Size(ulong value)67 public static int ComputeUInt64Size(ulong value) 68 { 69 return ComputeRawVarint64Size(value); 70 } 71 72 /// <summary> 73 /// Computes the number of bytes that would be needed to encode an 74 /// int64 field, including the tag. 75 /// </summary> ComputeInt64Size(long value)76 public static int ComputeInt64Size(long value) 77 { 78 return ComputeRawVarint64Size((ulong) value); 79 } 80 81 /// <summary> 82 /// Computes the number of bytes that would be needed to encode an 83 /// int32 field, including the tag. 84 /// </summary> ComputeInt32Size(int value)85 public static int ComputeInt32Size(int value) 86 { 87 if (value >= 0) 88 { 89 return ComputeRawVarint32Size((uint) value); 90 } 91 else 92 { 93 // Must sign-extend. 94 return 10; 95 } 96 } 97 98 /// <summary> 99 /// Computes the number of bytes that would be needed to encode a 100 /// fixed64 field, including the tag. 101 /// </summary> ComputeFixed64Size(ulong value)102 public static int ComputeFixed64Size(ulong value) 103 { 104 return LittleEndian64Size; 105 } 106 107 /// <summary> 108 /// Computes the number of bytes that would be needed to encode a 109 /// fixed32 field, including the tag. 110 /// </summary> ComputeFixed32Size(uint value)111 public static int ComputeFixed32Size(uint value) 112 { 113 return LittleEndian32Size; 114 } 115 116 /// <summary> 117 /// Computes the number of bytes that would be needed to encode a 118 /// bool field, including the tag. 119 /// </summary> ComputeBoolSize(bool value)120 public static int ComputeBoolSize(bool value) 121 { 122 return 1; 123 } 124 125 /// <summary> 126 /// Computes the number of bytes that would be needed to encode a 127 /// string field, including the tag. 128 /// </summary> ComputeStringSize(String value)129 public static int ComputeStringSize(String value) 130 { 131 int byteArraySize = Utf8Encoding.GetByteCount(value); 132 return ComputeLengthSize(byteArraySize) + byteArraySize; 133 } 134 135 /// <summary> 136 /// Computes the number of bytes that would be needed to encode a 137 /// group field, including the tag. 138 /// </summary> ComputeGroupSize(IMessage value)139 public static int ComputeGroupSize(IMessage value) 140 { 141 return value.CalculateSize(); 142 } 143 144 /// <summary> 145 /// Computes the number of bytes that would be needed to encode an 146 /// embedded message field, including the tag. 147 /// </summary> ComputeMessageSize(IMessage value)148 public static int ComputeMessageSize(IMessage value) 149 { 150 int size = value.CalculateSize(); 151 return ComputeLengthSize(size) + size; 152 } 153 154 /// <summary> 155 /// Computes the number of bytes that would be needed to encode a 156 /// bytes field, including the tag. 157 /// </summary> ComputeBytesSize(ByteString value)158 public static int ComputeBytesSize(ByteString value) 159 { 160 return ComputeLengthSize(value.Length) + value.Length; 161 } 162 163 /// <summary> 164 /// Computes the number of bytes that would be needed to encode a 165 /// uint32 field, including the tag. 166 /// </summary> ComputeUInt32Size(uint value)167 public static int ComputeUInt32Size(uint value) 168 { 169 return ComputeRawVarint32Size(value); 170 } 171 172 /// <summary> 173 /// Computes the number of bytes that would be needed to encode a 174 /// enum field, including the tag. The caller is responsible for 175 /// converting the enum value to its numeric value. 176 /// </summary> ComputeEnumSize(int value)177 public static int ComputeEnumSize(int value) 178 { 179 // Currently just a pass-through, but it's nice to separate it logically. 180 return ComputeInt32Size(value); 181 } 182 183 /// <summary> 184 /// Computes the number of bytes that would be needed to encode an 185 /// sfixed32 field, including the tag. 186 /// </summary> ComputeSFixed32Size(int value)187 public static int ComputeSFixed32Size(int value) 188 { 189 return LittleEndian32Size; 190 } 191 192 /// <summary> 193 /// Computes the number of bytes that would be needed to encode an 194 /// sfixed64 field, including the tag. 195 /// </summary> ComputeSFixed64Size(long value)196 public static int ComputeSFixed64Size(long value) 197 { 198 return LittleEndian64Size; 199 } 200 201 /// <summary> 202 /// Computes the number of bytes that would be needed to encode an 203 /// sint32 field, including the tag. 204 /// </summary> ComputeSInt32Size(int value)205 public static int ComputeSInt32Size(int value) 206 { 207 return ComputeRawVarint32Size(EncodeZigZag32(value)); 208 } 209 210 /// <summary> 211 /// Computes the number of bytes that would be needed to encode an 212 /// sint64 field, including the tag. 213 /// </summary> ComputeSInt64Size(long value)214 public static int ComputeSInt64Size(long value) 215 { 216 return ComputeRawVarint64Size(EncodeZigZag64(value)); 217 } 218 219 /// <summary> 220 /// Computes the number of bytes that would be needed to encode a length, 221 /// as written by <see cref="WriteLength"/>. 222 /// </summary> ComputeLengthSize(int length)223 public static int ComputeLengthSize(int length) 224 { 225 return ComputeRawVarint32Size((uint) length); 226 } 227 228 /// <summary> 229 /// Computes the number of bytes that would be needed to encode a varint. 230 /// </summary> ComputeRawVarint32Size(uint value)231 public static int ComputeRawVarint32Size(uint value) 232 { 233 if ((value & (0xffffffff << 7)) == 0) 234 { 235 return 1; 236 } 237 if ((value & (0xffffffff << 14)) == 0) 238 { 239 return 2; 240 } 241 if ((value & (0xffffffff << 21)) == 0) 242 { 243 return 3; 244 } 245 if ((value & (0xffffffff << 28)) == 0) 246 { 247 return 4; 248 } 249 return 5; 250 } 251 252 /// <summary> 253 /// Computes the number of bytes that would be needed to encode a varint. 254 /// </summary> ComputeRawVarint64Size(ulong value)255 public static int ComputeRawVarint64Size(ulong value) 256 { 257 if ((value & (0xffffffffffffffffL << 7)) == 0) 258 { 259 return 1; 260 } 261 if ((value & (0xffffffffffffffffL << 14)) == 0) 262 { 263 return 2; 264 } 265 if ((value & (0xffffffffffffffffL << 21)) == 0) 266 { 267 return 3; 268 } 269 if ((value & (0xffffffffffffffffL << 28)) == 0) 270 { 271 return 4; 272 } 273 if ((value & (0xffffffffffffffffL << 35)) == 0) 274 { 275 return 5; 276 } 277 if ((value & (0xffffffffffffffffL << 42)) == 0) 278 { 279 return 6; 280 } 281 if ((value & (0xffffffffffffffffL << 49)) == 0) 282 { 283 return 7; 284 } 285 if ((value & (0xffffffffffffffffL << 56)) == 0) 286 { 287 return 8; 288 } 289 if ((value & (0xffffffffffffffffL << 63)) == 0) 290 { 291 return 9; 292 } 293 return 10; 294 } 295 296 /// <summary> 297 /// Computes the number of bytes that would be needed to encode a tag. 298 /// </summary> ComputeTagSize(int fieldNumber)299 public static int ComputeTagSize(int fieldNumber) 300 { 301 return ComputeRawVarint32Size(WireFormat.MakeTag(fieldNumber, 0)); 302 } 303 } 304 }