/* Title: Pure/General/path.scala
Author: Makarius
Algebra of file-system paths: basic POSIX notation, extended by named
roots (e.g. //foo) and variables (e.g. $BAR).
*/
package isabelle
import java.io.{File => JFile}
import scala.util.matching.Regex
object Path
{
/* path elements */
sealed abstract class Elem
private case class Root(name: String) extends Elem
private case class Basic(name: String) extends Elem
private case class Variable(name: String) extends Elem
private case object Parent extends Elem
private def err_elem(msg: String, s: String): Nothing =
error(msg + " path element " + quote(s))
private val illegal_elem = Set("", "~", "~~", ".", "..")
private val illegal_char = "/\\$:\"'<>|?*"
private def check_elem(s: String): String =
if (illegal_elem.contains(s)) err_elem("Illegal", s)
else {
for (c <- s) {
if (c.toInt < 32)
err_elem("Illegal control character " + c.toInt + " in", s)
if (illegal_char.contains(c))
err_elem("Illegal character " + quote(c.toString) + " in", s)
}
s
}
private def root_elem(s: String): Elem = Root(check_elem(s))
private def basic_elem(s: String): Elem = Basic(check_elem(s))
private def variable_elem(s: String): Elem = Variable(check_elem(s))
private def apply_elem(y: Elem, xs: List[Elem]): List[Elem] =
(y, xs) match {
case (Root(_), _) => List(y)
case (Parent, Root(_) :: _) => xs
case (Parent, Basic(_) :: rest) => rest
case _ => y :: xs
}
private def norm_elems(elems: List[Elem]): List[Elem] =
(elems :\ (Nil: List[Elem]))(apply_elem)
private def implode_elem(elem: Elem, short: Boolean): String =
elem match {
case Root("") => ""
case Root(s) => "//" + s
case Basic(s) => s
case Variable("USER_HOME") if short => "~"
case Variable("ISABELLE_HOME") if short => "~~"
case Variable(s) => "$" + s
case Parent => ".."
}
/* path constructors */
val current: Path = new Path(Nil)
val root: Path = new Path(List(Root("")))
def named_root(s: String): Path = new Path(List(root_elem(s)))
def make(elems: List[String]): Path = new Path(elems.reverse.map(basic_elem))
def basic(s: String): Path = new Path(List(basic_elem(s)))
def variable(s: String): Path = new Path(List(variable_elem(s)))
val parent: Path = new Path(List(Parent))
/* explode */
def explode(str: String): Path =
{
def explode_elem(s: String): Elem =
try {
if (s == "..") Parent
else if (s == "~") Variable("USER_HOME")
else if (s == "~~") Variable("ISABELLE_HOME")
else if (s.startsWith("$")) variable_elem(s.substring(1))
else basic_elem(s)
}
catch { case ERROR(msg) => cat_error(msg, "The error(s) above occurred in " + quote(str)) }
val ss = space_explode('/', str)
val r = ss.takeWhile(_.isEmpty).length
val es = ss.dropWhile(_.isEmpty)
val (roots, raw_elems) =
if (r == 0) (Nil, es)
else if (r == 1) (List(Root("")), es)
else if (es.isEmpty) (List(Root("")), Nil)
else (List(root_elem(es.head)), es.tail)
val elems = raw_elems.filterNot(s => s.isEmpty || s == ".").map(explode_elem)
new Path(norm_elems(elems reverse_::: roots))
}
def is_wellformed(str: String): Boolean =
try { explode(str); true } catch { case ERROR(_) => false }
def is_valid(str: String): Boolean =
try { explode(str).expand; true } catch { case ERROR(_) => false }
def split(str: String): List[Path] =
space_explode(':', str).filterNot(_.isEmpty).map(explode)
/* encode */
val encode: XML.Encode.T[Path] = (path => XML.Encode.string(path.implode))
/* reserved names */
private val reserved_windows: Set[String] =
Set("CON", "PRN", "AUX", "NUL",
"COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9",
"LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9")
def is_reserved(name: String): Boolean =
Long_Name.explode(name).exists(a => reserved_windows.contains(Word.uppercase(a)))
/* case-insensitive names */
def check_case_insensitive(paths: List[Path])
{
val table =
(Multi_Map.empty[String, String] /: paths)({ case (tab, path) =>
val name = path.expand.implode
tab.insert(Word.lowercase(name), name)
})
val collisions =
(for { (_, coll) <- table.iterator_list if coll.length > 1 } yield coll).toList.flatten
if (collisions.nonEmpty) {
error(("Collision of file names due case-insensitivity:" :: collisions).mkString("\n "))
}
}
}
final class Path private(protected val elems: List[Path.Elem]) // reversed elements
{
override def hashCode: Int = elems.hashCode
override def equals(that: Any): Boolean =
that match {
case other: Path => elems == other.elems
case _ => false
}
def is_current: Boolean = elems.isEmpty
def is_absolute: Boolean = elems.nonEmpty && elems.last.isInstanceOf[Path.Root]
def is_root: Boolean = elems match { case List(Path.Root(_)) => true case _ => false }
def is_basic: Boolean = elems match { case List(Path.Basic(_)) => true case _ => false }
def starts_basic: Boolean = elems.nonEmpty && elems.last.isInstanceOf[Path.Basic]
def +(other: Path): Path = new Path((other.elems :\ elems)(Path.apply_elem))
/* implode */
private def gen_implode(short: Boolean): String =
elems match {
case Nil => "."
case List(Path.Root("")) => "/"
case _ => elems.map(Path.implode_elem(_, short)).reverse.mkString("/")
}
def implode: String = gen_implode(false)
def implode_short: String = gen_implode(true)
override def toString: String = quote(implode)
/* base element */
private def split_path: (Path, String) =
elems match {
case Path.Basic(s) :: xs => (new Path(xs), s)
case _ => error("Cannot split path into dir/base: " + toString)
}
def dir: Path = split_path._1
def base: Path = new Path(List(Path.Basic(split_path._2)))
def ext(e: String): Path =
if (e == "") this
else {
val (prfx, s) = split_path
prfx + Path.basic(s + "." + e)
}
def xz: Path = ext("xz")
def tex: Path = ext("tex")
def pdf: Path = ext("pdf")
def backup: Path =
{
val (prfx, s) = split_path
prfx + Path.basic(s + "~")
}
def backup2: Path =
{
val (prfx, s) = split_path
prfx + Path.basic(s + "~~")
}
def platform_exe: Path =
if (Platform.is_windows) ext("exe") else this
private val Ext = new Regex("(.*)\\.([^.]*)")
def split_ext: (Path, String) =
{
val (prefix, base) = split_path
base match {
case Ext(b, e) => (prefix + Path.basic(b), e)
case _ => (prefix + Path.basic(base), "")
}
}
def drop_ext: Path = split_ext._1
def get_ext: String = split_ext._2
/* expand */
def expand_env(env: Map[String, String]): Path =
{
def eval(elem: Path.Elem): List[Path.Elem] =
elem match {
case Path.Variable(s) =>
val path = Path.explode(Isabelle_System.getenv_strict(s, env))
if (path.elems.exists(_.isInstanceOf[Path.Variable]))
error("Illegal path variable nesting: " + s + "=" + path.toString)
else path.elems
case x => List(x)
}
new Path(Path.norm_elems(elems.flatMap(eval)))
}
def expand: Path = expand_env(Isabelle_System.settings())
def file_name: String = expand.base.implode
/* source position */
def position: Position.T = Position.File(implode)
/* platform files */
def file: JFile = File.platform_file(this)
def is_file: Boolean = file.isFile
def is_dir: Boolean = file.isDirectory
def absolute_file: JFile = File.absolute(file)
def canonical_file: JFile = File.canonical(file)
def absolute: Path = File.path(absolute_file)
def canonical: Path = File.path(canonical_file)
}