/usr/share/gocode/src/github.com/dlclark/regexp2/regexp.go is in golang-github-dlclark-regexp2-dev 1.1.6-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 | /*
Package regexp2 is a regexp package that has an interface similar to Go's framework regexp engine but uses a
more feature full regex engine behind the scenes.
It doesn't have constant time guarantees, but it allows backtracking and is compatible with Perl5 and .NET.
You'll likely be better off with the RE2 engine from the regexp package and should only use this if you
need to write very complex patterns or require compatibility with .NET.
*/
package regexp2
import (
"errors"
"math"
"strconv"
"sync"
"time"
"github.com/dlclark/regexp2/syntax"
)
// Default timeout used when running regexp matches -- "forever"
var DefaultMatchTimeout = time.Duration(math.MaxInt64)
// Regexp is the representation of a compiled regular expression.
// A Regexp is safe for concurrent use by multiple goroutines.
type Regexp struct {
//timeout when trying to find matches
MatchTimeout time.Duration
// read-only after Compile
pattern string // as passed to Compile
options RegexOptions // options
caps map[int]int // capnum->index
capnames map[string]int //capture group name -> index
capslist []string //sorted list of capture group names
capsize int // size of the capture array
code *syntax.Code // compiled program
// cache of machines for running regexp
muRun sync.Mutex
runner []*runner
}
// Compile parses a regular expression and returns, if successful,
// a Regexp object that can be used to match against text.
func Compile(expr string, opt RegexOptions) (*Regexp, error) {
// parse it
tree, err := syntax.Parse(expr, syntax.RegexOptions(opt))
if err != nil {
return nil, err
}
// translate it to code
code, err := syntax.Write(tree)
if err != nil {
return nil, err
}
// return it
return &Regexp{
pattern: expr,
options: opt,
caps: code.Caps,
capnames: tree.Capnames,
capslist: tree.Caplist,
capsize: code.Capsize,
code: code,
MatchTimeout: DefaultMatchTimeout,
}, nil
}
// MustCompile is like Compile but panics if the expression cannot be parsed.
// It simplifies safe initialization of global variables holding compiled regular
// expressions.
func MustCompile(str string, opt RegexOptions) *Regexp {
regexp, error := Compile(str, opt)
if error != nil {
panic(`regexp2: Compile(` + quote(str) + `): ` + error.Error())
}
return regexp
}
// Escape adds backslashes to any special characters in the input string
func Escape(input string) string {
return syntax.Escape(input)
}
// Unescape removes any backslashes from previously-escaped special characters in the input string
func Unescape(input string) (string, error) {
return syntax.Unescape(input)
}
// String returns the source text used to compile the regular expression.
func (re *Regexp) String() string {
return re.pattern
}
func quote(s string) string {
if strconv.CanBackquote(s) {
return "`" + s + "`"
}
return strconv.Quote(s)
}
// RegexOptions impact the runtime and parsing behavior
// for each specific regex. They are setable in code as well
// as in the regex pattern itself.
type RegexOptions int32
const (
None RegexOptions = 0x0
IgnoreCase = 0x0001 // "i"
Multiline = 0x0002 // "m"
ExplicitCapture = 0x0004 // "n"
Compiled = 0x0008 // "c"
Singleline = 0x0010 // "s"
IgnorePatternWhitespace = 0x0020 // "x"
RightToLeft = 0x0040 // "r"
Debug = 0x0080 // "d"
ECMAScript = 0x0100 // "e"
)
func (re *Regexp) RightToLeft() bool {
return re.options&RightToLeft != 0
}
func (re *Regexp) Debug() bool {
return re.options&Debug != 0
}
// Replace searches the input string and replaces each match found with the replacement text.
// Count will limit the number of matches attempted and startAt will allow
// us to skip past possible matches at the start of the input (left or right depending on RightToLeft option).
// Set startAt and count to -1 to go through the whole string
func (re *Regexp) Replace(input, replacement string, startAt, count int) (string, error) {
data, err := syntax.NewReplacerData(replacement, re.caps, re.capsize, re.capnames, syntax.RegexOptions(re.options))
if err != nil {
return "", err
}
//TODO: cache ReplacerData
return replace(re, data, nil, input, startAt, count)
}
// ReplaceFunc searches the input string and replaces each match found using the string from the evaluator
// Count will limit the number of matches attempted and startAt will allow
// us to skip past possible matches at the start of the input (left or right depending on RightToLeft option).
// Set startAt and count to -1 to go through the whole string.
func (re *Regexp) ReplaceFunc(input string, evaluator MatchEvaluator, startAt, count int) (string, error) {
return replace(re, nil, evaluator, input, startAt, count)
}
// FindStringMatch searches the input string for a Regexp match
func (re *Regexp) FindStringMatch(s string) (*Match, error) {
// convert string to runes
return re.run(false, -1, getRunes(s))
}
// FindRunesMatch searches the input rune slice for a Regexp match
func (re *Regexp) FindRunesMatch(r []rune) (*Match, error) {
return re.run(false, -1, r)
}
// FindStringMatchStartingAt searches the input string for a Regexp match starting at the startAt index
func (re *Regexp) FindStringMatchStartingAt(s string, startAt int) (*Match, error) {
if startAt > len(s) {
return nil, errors.New("startAt must be less than the length of the input string")
}
r, startAt := re.getRunesAndStart(s, startAt)
if startAt == -1 {
// we didn't find our start index in the string -- that's a problem
return nil, errors.New("startAt must align to the start of a valid rune in the input string")
}
return re.run(false, startAt, r)
}
// FindRunesMatchStartingAt searches the input rune slice for a Regexp match starting at the startAt index
func (re *Regexp) FindRunesMatchStartingAt(r []rune, startAt int) (*Match, error) {
return re.run(false, startAt, r)
}
// FindNextMatch returns the next match in the same input string as the match parameter.
// Will return nil if there is no next match or if given a nil match.
func (re *Regexp) FindNextMatch(m *Match) (*Match, error) {
if m == nil {
return nil, nil
}
// If previous match was empty, advance by one before matching to prevent
// infinite loop
startAt := m.textpos
if m.Length == 0 {
if m.textpos == len(m.text) {
return nil, nil
}
if re.RightToLeft() {
startAt--
} else {
startAt++
}
}
return re.run(false, startAt, m.text)
}
// MatchString return true if the string matches the regex
// error will be set if a timeout occurs
func (re *Regexp) MatchString(s string) (bool, error) {
m, err := re.run(true, -1, getRunes(s))
if err != nil {
return false, err
}
return m != nil, nil
}
func (re *Regexp) getRunesAndStart(s string, startAt int) ([]rune, int) {
if startAt < 0 {
if re.RightToLeft() {
r := getRunes(s)
return r, len(r)
}
return getRunes(s), 0
}
ret := make([]rune, len(s))
i := 0
runeIdx := -1
for strIdx, r := range s {
if strIdx == startAt {
runeIdx = i
}
ret[i] = r
i++
}
return ret[:i], runeIdx
}
func getRunes(s string) []rune {
ret := make([]rune, len(s))
i := 0
for _, r := range s {
ret[i] = r
i++
}
return ret[:i]
}
// MatchRunes return true if the runes matches the regex
// error will be set if a timeout occurs
func (re *Regexp) MatchRunes(r []rune) (bool, error) {
m, err := re.run(true, -1, r)
if err != nil {
return false, err
}
return m != nil, nil
}
// GetGroupNames Returns the set of strings used to name capturing groups in the expression.
func (re *Regexp) GetGroupNames() []string {
var result []string
if re.capslist == nil {
result = make([]string, re.capsize)
for i := 0; i < len(result); i++ {
result[i] = strconv.Itoa(i)
}
} else {
result = make([]string, len(re.capslist))
copy(result, re.capslist)
}
return result
}
// GetGroupNumbers returns the integer group numbers corresponding to a group name.
func (re *Regexp) GetGroupNumbers() []int {
var result []int
if re.caps == nil {
result = make([]int, re.capsize)
for i := 0; i < len(result); i++ {
result[i] = i
}
} else {
result = make([]int, len(re.caps))
for k, v := range re.caps {
result[v] = k
}
}
return result
}
// GroupNameFromNumber retrieves a group name that corresponds to a group number.
// It will return "" for and unknown group number. Unnamed groups automatically
// receive a name that is the decimal string equivalent of its number.
func (re *Regexp) GroupNameFromNumber(i int) string {
if re.capslist == nil {
if i >= 0 && i < re.capsize {
return strconv.Itoa(i)
}
return ""
}
if re.caps != nil {
var ok bool
if i, ok = re.caps[i]; !ok {
return ""
}
}
if i >= 0 && i < len(re.capslist) {
return re.capslist[i]
}
return ""
}
// GroupNumberFromName returns a group number that corresponds to a group name.
// Returns -1 if the name is not a recognized group name. Numbered groups
// automatically get a group name that is the decimal string equivalent of its number.
func (re *Regexp) GroupNumberFromName(name string) int {
// look up name if we have a hashtable of names
if re.capnames != nil {
if k, ok := re.capnames[name]; ok {
return k
}
return -1
}
// convert to an int if it looks like a number
result := 0
for i := 0; i < len(name); i++ {
ch := name[i]
if ch > '9' || ch < '0' {
return -1
}
result *= 10
result += int(ch - '0')
}
// return int if it's in range
if result >= 0 && result < re.capsize {
return result
}
return -1
}
|