File: coma.go 1 /* 2 The MIT License (MIT) 3 4 Copyright © 2020-2025 pacman64 5 6 Permission is hereby granted, free of charge, to any person obtaining a copy of 7 this software and associated documentation files (the “Software”), to deal 8 in the Software without restriction, including without limitation the rights to 9 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 10 of the Software, and to permit persons to whom the Software is furnished to do 11 so, subject to the following conditions: 12 13 The above copyright notice and this permission notice shall be included in all 14 copies or substantial portions of the Software. 15 16 THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 19 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 SOFTWARE. 23 */ 24 25 /* 26 Single-file source-code for coma. 27 28 To compile a smaller-sized command-line app, you can use the `go` command as 29 follows: 30 31 go build -ldflags "-s -w" -trimpath coma.go 32 */ 33 34 package main 35 36 import ( 37 "bufio" 38 "bytes" 39 "os" 40 "regexp" 41 ) 42 43 var styleAliases = map[string]string{ 44 `b`: `blue`, 45 `g`: `green`, 46 `m`: `magenta`, 47 `o`: `orange`, 48 `p`: `purple`, 49 `r`: `red`, 50 `u`: `underline`, 51 52 `bb`: `blueback`, 53 `bg`: `greenback`, 54 `bm`: `magentaback`, 55 `bo`: `orangeback`, 56 `bp`: `purpleback`, 57 `br`: `redback`, 58 59 `gb`: `greenback`, 60 `mb`: `magentaback`, 61 `ob`: `orangeback`, 62 `pb`: `purpleback`, 63 `rb`: `redback`, 64 65 `hi`: `inverse`, 66 `inv`: `inverse`, 67 `mag`: `magenta`, 68 69 `du`: `doubleunderline`, 70 71 `flip`: `inverse`, 72 `swap`: `inverse`, 73 74 `reset`: `plain`, 75 `highlight`: `inverse`, 76 `hilite`: `inverse`, 77 `invert`: `inverse`, 78 `inverted`: `inverse`, 79 `swapped`: `inverse`, 80 81 `dunderline`: `doubleunderline`, 82 `dunderlined`: `doubleunderline`, 83 84 `strikethrough`: `strike`, 85 `strikethru`: `strike`, 86 `struck`: `strike`, 87 88 `underlined`: `underline`, 89 90 `bblue`: `blueback`, 91 `bgray`: `grayback`, 92 `bgreen`: `greenback`, 93 `bmagenta`: `magentaback`, 94 `borange`: `orangeback`, 95 `bpurple`: `purpleback`, 96 `bred`: `redback`, 97 98 `bgblue`: `blueback`, 99 `bggray`: `grayback`, 100 `bggreen`: `greenback`, 101 `bgmag`: `magentaback`, 102 `bgmagenta`: `magentaback`, 103 `bgorange`: `orangeback`, 104 `bgpurple`: `purpleback`, 105 `bgred`: `redback`, 106 107 `bluebg`: `blueback`, 108 `graybg`: `grayback`, 109 `greenbg`: `greenback`, 110 `magbg`: `magentaback`, 111 `magentabg`: `magentaback`, 112 `orangebg`: `orangeback`, 113 `purplebg`: `purpleback`, 114 `redbg`: `redback`, 115 116 `backblue`: `blueback`, 117 `backgray`: `grayback`, 118 `backgreen`: `greenback`, 119 `backmag`: `magentaback`, 120 `backmagenta`: `magentaback`, 121 `backorange`: `orangeback`, 122 `backpurple`: `purpleback`, 123 `backred`: `redback`, 124 } 125 126 var styles = map[string]string{ 127 `blue`: "\x1b[38;2;0;95;215m", 128 `bold`: "\x1b[1m", 129 `doubleunderline`: "\x1b[21m", 130 `gray`: "\x1b[38;2;168;168;168m", 131 `green`: "\x1b[38;2;0;135;95m", 132 `inverse`: "\x1b[7m", 133 `magenta`: "\x1b[38;2;215;0;255m", 134 `orange`: "\x1b[38;2;215;95;0m", 135 `plain`: "\x1b[0m", 136 `purple`: "\x1b[38;2;135;95;255m", 137 `red`: "\x1b[38;2;204;0;0m", 138 `strike`: "\x1b[9m", 139 `underline`: "\x1b[4m", 140 141 `blueback`: "\x1b[48;2;0;95;215m\x1b[38;2;238;238;238m", 142 `grayback`: "\x1b[48;2;168;168;168m\x1b[38;2;238;238;238m", 143 `greenback`: "\x1b[48;2;0;135;95m\x1b[38;2;238;238;238m", 144 `magentaback`: "\x1b[48;2;215;0;255m\x1b[38;2;238;238;238m", 145 `orangeback`: "\x1b[48;2;215;95;0m\x1b[38;2;238;238;238m", 146 `purpleback`: "\x1b[48;2;135;95;255m\x1b[38;2;238;238;238m", 147 `redback`: "\x1b[48;2;204;0;0m\x1b[38;2;238;238;238m", 148 } 149 150 type patternStylePair struct { 151 expr *regexp.Regexp 152 style string 153 } 154 155 func main() { 156 if len(os.Args)%2 != 1 { 157 const msg = `you forgot the style-name for/after the last regex` 158 os.Stderr.WriteString("\x1b[31m") 159 os.Stderr.WriteString(msg) 160 os.Stderr.WriteString("\x1b[0m\n") 161 os.Exit(1) 162 } 163 164 nerr := 0 165 pairs := make([]patternStylePair, 0, len(os.Args[1:])/2) 166 167 for args := os.Args[1:]; len(args) >= 2; args = args[2:] { 168 resrc := args[0] 169 sname := args[1] 170 171 e, err := regexp.Compile(resrc) 172 if err != nil { 173 os.Stderr.WriteString("\x1b[31m") 174 os.Stderr.WriteString(err.Error()) 175 os.Stderr.WriteString("\x1b[0m\n") 176 nerr++ 177 } 178 179 if alias, ok := styleAliases[sname]; ok { 180 sname = alias 181 } 182 183 style, ok := styles[sname] 184 if !ok { 185 os.Stderr.WriteString("\x1b[31mno style named `") 186 os.Stderr.WriteString(args[1]) 187 os.Stderr.WriteString("`\x1b[0m\n") 188 nerr++ 189 } 190 191 pairs = append(pairs, patternStylePair{expr: e, style: style}) 192 } 193 194 if nerr > 0 { 195 os.Exit(1) 196 } 197 198 sc := bufio.NewScanner(os.Stdin) 199 sc.Buffer(nil, 8*1024*1024*1024) 200 bw := bufio.NewWriter(os.Stdout) 201 202 for sc.Scan() { 203 handleLine(bw, sc.Bytes(), pairs) 204 bw.WriteByte('\n') 205 if err := bw.Flush(); err != nil { 206 return 207 } 208 } 209 } 210 211 // indexEscapeSequence finds the first ANSI-style escape-sequence, which is 212 // either the alert/bell byte, or the multi-byte sequences starting either 213 // with ESC[ or ESC]; either returned index can be negative 214 func indexEscapeSequence(s []byte) (int, int) { 215 var prev byte 216 217 for i, b := range s { 218 if b == '\a' { 219 return i, i + 1 220 } 221 222 if prev == '\x1b' && b == '[' { 223 j := indexLetter(s[i+1:]) 224 if j < 0 { 225 return i, -1 226 } 227 return i - 1, i + 1 + j + 1 228 } 229 230 if prev == '\x1b' && b == ']' { 231 j := bytes.IndexByte(s[i+1:], ':') 232 if j < 0 { 233 return i, -1 234 } 235 return i - 1, i + 1 + j + 1 236 } 237 238 if prev == '\x1b' && b == '\\' { 239 return i - 1, i + 1 240 } 241 242 prev = b 243 } 244 245 return -1, -1 246 } 247 248 func indexLetter(s []byte) int { 249 for i, b := range s { 250 if 'A' <= b && b <= 'Z' { 251 return i 252 } 253 if 'a' <= b && b <= 'z' { 254 return i 255 } 256 } 257 258 return -1 259 } 260 261 func handleLine(w *bufio.Writer, s []byte, with []*regexp.Regexp) { 262 for len(s) > 0 { 263 i, j := indexEscapeSequence(s) 264 if i < 0 { 265 handleLineChunk(w, s, with) 266 return 267 } 268 269 handleLineChunk(w, s[:i], with) 270 w.Write(s[i:j]) 271 272 if j < 0 { 273 break 274 } 275 s = s[j:] 276 } 277 } 278 279 func handleLineChunk(w *bufio.Writer, s []byte, with []patternStylePair) { 280 start := -1 281 end := -1 282 which := -1 283 284 for len(s) > 0 { 285 start = -1 286 for i, pair := range with { 287 span := pair.expr.FindIndex(s) 288 if span != nil && (span[0] < start || start < 0) { 289 start = span[0] 290 end = span[1] 291 which = i 292 } 293 } 294 295 if start < 0 { 296 w.Write(s) 297 return 298 } 299 300 w.Write(s[:start]) 301 w.WriteString(with[which].style) 302 w.Write(s[start:end]) 303 w.WriteString("\x1b[0m") 304 s = s[end:] 305 } 306 }