/usr/share/scsh-0.6/scsh/glob.scm is in scsh-common-0.6 0.6.7-8.
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 | ;;; Code for processing file names with a glob pattern.
;;; Copyright (c) 1994 by David Albertz (dalbertz@clark.lcs.mit.edu).
;;; Copyright (c) 1994 by Olin Shivers (shivers@clark.lcs.mit.edu).
;;; See file COPYING.
;;; Usage: (glob pattern-list)
;;; pattern-list := a list of glob-pattern strings
;;; Return: list of file names (strings)
;;; The files "." and ".." are never returned by glob.
;;; Dot files will only be returned if the first character
;;; of a glob pattern is a ".".
;;; The empty pattern matches nothing.
;;; A pattern beginning with / starts at root; otherwise, we start at cwd.
;;; A pattern ending with / matches only directories, e.g., "/usr/man/man?/"
(define (glob . pattern-list)
;; Expand out braces, and apply GLOB-ONE-PATTERN to all the result patterns.
(apply append
(map glob-one-pattern
(apply append (map glob-remove-braces pattern-list)))))
(define (glob-one-pattern pattern)
(let ((plen (string-length pattern)))
(if (zero? plen) '()
(let ((directories-only? (char=? #\/ (string-ref pattern (- plen 1))))
(patterns (split-file-name pattern))) ; Must be non-null.
(if (equal? "" (car patterns))
(really-glob "" (cdr patterns) directories-only?) ; root
(really-glob "." patterns directories-only?)))))) ; cwd
(define (really-glob root-file patterns directories-only?)
;; This is the heart of the matcher.
(let recur ((file root-file)
(pats patterns)
(sure? #f)) ; True if we are sure this file exists.
(if (pair? pats)
(let ((pat (car pats))
(pats (cdr pats))
(dir (file-name-as-directory file)))
(receive (winners sure?) (glob-subpat dir pat)
(apply append (map (lambda (f)
(recur (string-append dir f) pats sure?))
winners))))
;; All done.
(if directories-only?
(if (maybe-isdir? file)
(list (file-name-as-directory file))
'())
(if (or sure? (file-exists? file))
(list file)
'())))))
;;; Return the elts of directory FNAME that match pattern PAT.
;;; If PAT contains no wildcards, we cheat and do not match the
;;; constant pattern against every file in FNAME/; we just
;;; immediately return FNAME/PAT. In this case, we indicate that we
;;; aren't actually sure the file exists by returning a true SURE?
;;; value. Not only does this vastly speed up the matcher, it also
;;; allows us to match the constant patterns "." and "..".
(define (glob-subpat fname pat) ; PAT doesn't contain a slash.
(cond ((string=? pat "") (values '() #t))
((constant-glob? pat)
(values (cons (glob-unquote pat) '()) #f)) ; Don't check filesys.
(else (let* ((dots? (char=? #\. (string-ref pat 0))) ; Match dot files?
(candidates (maybe-directory-files fname dots?))
(re (glob->regexp pat)))
(values (filter (lambda (f) (regexp-search? re f)) candidates)
#t))))) ; These guys exist for sure.
;;; The initial special-case above isn't really for the fast-path; it's
;;; an obscure and unlikely case. But since we have to check pat[0] for an
;;; initial dot, we have to do the check anyway...
;;; Translate a brace-free glob pattern to a regular expression.
(define glob->regexp
(let ((dot-star (re-repeat 0 #f re-any))) ; ".*" or (* any)
(lambda (pat)
(let ((pat-len (string-length pat))
(str-cons (lambda (chars res) ; Reverse CHARS and cons the
(if (pair? chars) ; result string-re onto RES.
(cons (re-string (list->string (reverse chars)))
res)
res))))
;; We accumulate chars into CHARS, and coalesce into a single string
;; with STR-CONS when we run across a non-char.
(let lp ((chars '())
(res (list re-bos))
(i 0))
(if (= i pat-len)
(re-seq (reverse (cons re-eos (str-cons chars res))))
(let ((c (string-ref pat i))
(i (+ i 1)))
(case c
((#\\) (if (< i pat-len)
(lp (cons (string-ref pat i) chars)
res (+ i 1))
(error "Ill-formed glob pattern -- ends in backslash" pat)))
((#\*) (lp '()
(cons dot-star (str-cons chars res))
i))
((#\?) (lp '()
(cons re-any (str-cons chars res))
i))
((#\[) (receive (re i) (parse-glob-bracket pat i)
(lp '()
(cons re (str-cons chars res))
i)))
(else (lp (cons c chars) res i))))))))))
;;; A glob bracket expression is [...] or [^...].
;;; The body is a sequence of <char> and <char>-<char> ranges.
;;; A <char> is any character except right-bracket, carat, hypen or backslash,
;;; or a backslash followed by any character at all.
(define (parse-glob-bracket pat i)
(let ((pat-len (string-length pat)))
(receive (negate? i) (if (and (< i pat-len) (char=? #\^ (string-ref pat i)))
(values #t (+ i 1))
(values #f i))
(let lp ((elts '()) (i i))
(if (>= i pat-len)
(error "Ill-formed glob pattern -- no terminating close-bracket" pat)
(let ((c (string-ref pat i))
(i (+ i 1)))
(case c
((#\])
(let ((cset (fold (lambda (elt cset)
(if (char? elt)
(char-set-adjoin! cset elt)
(ucs-range->char-set! (char->ascii (car elt))
(+ 1 (char->ascii (cdr elt)))
#f cset)))
(char-set-copy char-set:empty)
elts)))
(values (re-char-set (if negate?
(char-set-complement! cset)
cset))
i)))
((#\\)
(if (>= i pat-len)
(error "Ill-formed glob pattern -- ends in backslash" pat)
(lp (cons (string-ref pat i) elts) (+ i 1))))
((#\-)
(cond ((>= i pat-len)
(error "Ill-formed glob pattern -- unterminated range." pat))
((or (null? elts) (not (char? (car elts))))
(error "Ill-formed glob pattern -- range has no beginning." pat))
(else (lp (cons (cons (car elts) (string-ref pat i)) elts)
(+ i 1)))))
(else (lp (cons c elts) i)))))))))
;;; Is the glob pattern free of *'s, ?'s and [...]'s?
(define (constant-glob? pattern)
(let ((patlen (string-length pattern)))
(let lp ((i 0))
(or (= i patlen)
(let ((next-i (+ i 1)))
(case (string-ref pattern i)
((#\\) ; Escape char
(if (= next-i patlen)
(error "Ill-formed glob pattern -- ends in backslash"
pattern)
(lp (+ next-i 1))))
((#\* #\? #\[) #f)
(else (lp next-i))))))))
;;; Make an effort to get the files in the putative directory PATH.
;;; If PATH isn't a directory, or some filesys error happens (such
;;; as a broken symlink, or a permissions problem), don't error out,
;;; just quietly return the empty list.
(define (maybe-directory-files path dotfiles?)
(with-errno-handler ((errno data)
(else '())) ; On any error, return ().
(directory-files (if (string=? path "") "." path) dotfiles?)))
;;; Make an effort to find out if the file is a directory. If there's
;;; any error, return #f.
(define (maybe-isdir? path)
(with-errno-handler ((errno data)
(else #f)) ; On any error, return #f.
(file-directory? path)))
;;; This section of code is responsible for processing the braces in glob
;;; patterns. I.e., "{foo,bar}/*.c" -> ("foo/*.c" "bar/*.c")
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(define (append-suffix strs suffix)
(map (lambda (s) (string-append s suffix)) strs))
(define (cross-append prefixes suffixes)
(apply append (map (lambda (sfx) (append-suffix prefixes sfx)) suffixes)))
;;; Parse a glob pattern into an equivalent series of brace-free patterns.
;;; The pattern starts at START and is terminated by (1) end of string,
;;; (2) an unmatched close brace, or (3) a comma (if COMMA-TERMINATES? is set).
;;; Returns two values:
;;; - the list of patterns
;;; - the string index after the pattern terminates. This points at
;;; the comma or brace if they terminated the scan, since they are
;;; not part of the pattern.
(define (parse-glob-braces pattern start comma-terminates?)
(let ((pattern-len (string-length pattern))
(finish (lambda (prefixes pat)
(append-suffix prefixes (list->string (reverse pat))))))
(let lp ((i start)
(prefixes '(""))
(pat '()))
(if (= i pattern-len)
(values (finish prefixes pat) i)
(let ((c (string-ref pattern i)))
(case c
((#\{)
(let ((prefixes (append-suffix prefixes
(list->string (reverse pat)))))
(receive (pats i)
(parse-comma-sequence pattern (+ i 1))
(lp i (cross-append prefixes pats) '()))))
((#\\)
(let ((next-i (+ i 1)))
(if (= next-i pattern-len)
(error "Dangling escape char in glob pattern" pattern)
(if (memv (string-ref pattern next-i) '(#\{, #\,, #\},#\\))
(lp (+ next-i 1)
prefixes
(cons (string-ref pattern next-i) pat))
(lp (+ i 1)
prefixes
(cons (string-ref pattern i) pat))))))
((#\,)
(if comma-terminates?
(values (finish prefixes pat) i)
(lp (+ i 1) prefixes (cons c pat))))
((#\})
(values (finish prefixes pat) i))
(else
(lp (+ i 1) prefixes (cons c pat)))))))))
;;; Parse the internals of a {foo,bar,baz} brace list from a glob pattern.
;;; START is the index of the char following the open brace.
;;; Returns two values:
;;; - an equivalent list of brace-free glob patterns
;;; - the index of the char after the terminating brace
(define (parse-comma-sequence pattern start)
(let ((pattern-len (string-length pattern)))
(let lp ((i start)
(patterns '())) ; The list of comma-separated patterns read.
(if (= i pattern-len)
(error "Glob brace-expression pattern not terminated" pattern)
(receive (pats i) (parse-glob-braces pattern i #t)
(let ((patterns (append patterns pats)))
(if (= i pattern-len)
(error "Unterminated brace in glob pattern" pattern)
(let ((c (string-ref pattern i)))
(case c
((#\})
(values patterns (+ i 1)))
((#\,)
(lp (+ i 1) patterns))
(else
(error "glob parser internal error" pattern i)))))))))))
(define (glob-remove-braces pattern)
(receive (pats i) (parse-glob-braces pattern 0 #f)
(if (= i (string-length pattern)) pats
(error "Unmatched close brace in glob pattern" pattern i))))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Convert a string into a glob pattern that matches that string exactly --
;;; in other words, quote the \ * ? [] and {} chars with backslashes.
(define (glob-quote string)
(let lp ((i (- (string-length string) 1))
(result '()))
(if (< i 0) (list->string result)
(lp (- i 1)
(let* ((c (string-ref string i))
(result (cons c result)))
(if (memv c '(#\[ #\] #\* #\? #\{ #\} #\\))
(cons #\\ result)
result))))))
(define (glob-unquote string)
(let ((len (string-length string)))
(let lp ((i 0)
(result '()))
(if (= i len)
(list->string (reverse result))
(let* ((c (string-ref string i)))
(if (char=? c #\\)
(let ((next-i (+ i 1)))
(if (= next-i len)
(error "Dangling escape char in glob pattern" string)
(let ((quoted (string-ref string next-i)))
(lp (+ i 2)
(cons quoted result)))))
(lp (+ i 1)
(cons c result))))))))
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