1 /* 2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org> 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining 5 * a copy of this software and associated documentation files (the 6 * "Software"), to deal in the Software without restriction, including 7 * without limitation the rights to use, copy, modify, merge, publish, 8 * distribute, sublicense, and/or sell copies of the Software, and to 9 * permit persons to whom the Software is furnished to do so, subject to 10 * the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be 13 * included in all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 * SOFTWARE. 23 */ 24 25 using System; 26 using System.Collections.Generic; 27 using System.Text; 28 29 class ConstData { 30 31 internal long ID { get; private set; } 32 internal int Address { get; set; } 33 internal int Length { 34 get { 35 return len; 36 } 37 } 38 39 byte[] buf; 40 int len; 41 42 internal ConstData(T0Comp ctx) 43 { 44 ID = ctx.NextBlobID(); 45 buf = new byte[4]; 46 len = 0; 47 } 48 49 void Expand(int elen) 50 { 51 int tlen = len + elen; 52 if (tlen > buf.Length) { 53 int nlen = Math.Max(buf.Length << 1, tlen); 54 byte[] nbuf = new byte[nlen]; 55 Array.Copy(buf, 0, nbuf, 0, len); 56 buf = nbuf; 57 } 58 } 59 60 internal void Add8(byte b) 61 { 62 Expand(1); 63 buf[len ++] = b; 64 } 65 66 internal void Add16(int x) 67 { 68 Expand(2); 69 buf[len ++] = (byte)(x >> 8); 70 buf[len ++] = (byte)x; 71 } 72 73 internal void Add24(int x) 74 { 75 Expand(3); 76 buf[len ++] = (byte)(x >> 16); 77 buf[len ++] = (byte)(x >> 8); 78 buf[len ++] = (byte)x; 79 } 80 81 internal void Add32(int x) 82 { 83 Expand(4); 84 buf[len ++] = (byte)(x >> 24); 85 buf[len ++] = (byte)(x >> 16); 86 buf[len ++] = (byte)(x >> 8); 87 buf[len ++] = (byte)x; 88 } 89 90 internal void AddString(string s) 91 { 92 byte[] sd = Encoding.UTF8.GetBytes(s); 93 Expand(sd.Length + 1); 94 Array.Copy(sd, 0, buf, len, sd.Length); 95 buf[len + sd.Length] = 0; 96 len += sd.Length + 1; 97 } 98 99 void CheckIndex(int off, int dlen) 100 { 101 if (off < 0 || off > (len - dlen)) { 102 throw new IndexOutOfRangeException(); 103 } 104 } 105 106 internal void Set8(int off, byte v) 107 { 108 CheckIndex(off, 1); 109 buf[off] = v; 110 } 111 112 internal byte Read8(int off) 113 { 114 CheckIndex(off, 1); 115 return buf[off]; 116 } 117 118 internal int Read16(int off) 119 { 120 CheckIndex(off, 2); 121 return (buf[off] << 8) | buf[off + 1]; 122 } 123 124 internal int Read24(int off) 125 { 126 CheckIndex(off, 3); 127 return (buf[off] << 16) | (buf[off + 1] << 8) | buf[off + 2]; 128 } 129 130 internal int Read32(int off) 131 { 132 CheckIndex(off, 4); 133 return (buf[off] << 24) | (buf[off + 1] << 16) 134 | (buf[off + 2] << 8) | buf[off + 3]; 135 } 136 137 internal string ToString(int off) 138 { 139 StringBuilder sb = new StringBuilder(); 140 for (;;) { 141 int x = DecodeUTF8(ref off); 142 if (x == 0) { 143 return sb.ToString(); 144 } 145 if (x < 0x10000) { 146 sb.Append((char)x); 147 } else { 148 x -= 0x10000; 149 sb.Append((char)(0xD800 + (x >> 10))); 150 sb.Append((char)(0xDC00 + (x & 0x3FF))); 151 } 152 } 153 } 154 155 int DecodeUTF8(ref int off) 156 { 157 if (off >= len) { 158 throw new IndexOutOfRangeException(); 159 } 160 int x = buf[off ++]; 161 if (x < 0xC0 || x > 0xF7) { 162 return x; 163 } 164 int elen, acc; 165 if (x >= 0xF0) { 166 elen = 3; 167 acc = x & 0x07; 168 } else if (x >= 0xE0) { 169 elen = 2; 170 acc = x & 0x0F; 171 } else { 172 elen = 1; 173 acc = x & 0x1F; 174 } 175 if (off + elen > len) { 176 return x; 177 } 178 for (int i = 0; i < elen; i ++) { 179 int y = buf[off + i]; 180 if (y < 0x80 || y >= 0xC0) { 181 return x; 182 } 183 acc = (acc << 6) + (y & 0x3F); 184 } 185 if (acc > 0x10FFFF) { 186 return x; 187 } 188 off += elen; 189 return acc; 190 } 191 192 internal void Encode(BlobWriter bw) 193 { 194 for (int i = 0; i < len; i ++) { 195 bw.Append(buf[i]); 196 } 197 } 198 } 199