(* Title: Pure/General/file.ML
Author: Markus Wenzel, TU Muenchen
File system operations.
*)
signature FILE =
sig
val platform_path: Path.T -> string
val shell_quote: string -> string
val shell_path: Path.T -> string
val cd: Path.T -> unit
val pwd: unit -> Path.T
val full_path: Path.T -> Path.T -> Path.T
val tmp_path: Path.T -> Path.T
val exists: Path.T -> bool
val rm: Path.T -> unit
val is_dir: Path.T -> bool
val check_dir: Path.T -> Path.T
val check_file: Path.T -> Path.T
val open_input: (TextIO.instream -> 'a) -> Path.T -> 'a
val open_output: (TextIO.outstream -> 'a) -> Path.T -> 'a
val open_append: (TextIO.outstream -> 'a) -> Path.T -> 'a
val fold_lines: (string -> 'a -> 'a) -> Path.T -> 'a -> 'a
val read: Path.T -> string
val write: Path.T -> string -> unit
val append: Path.T -> string -> unit
val write_list: Path.T -> string list -> unit
val append_list: Path.T -> string list -> unit
val write_buffer: Path.T -> Buffer.T -> unit
val eq: Path.T * Path.T -> bool
val copy: Path.T -> Path.T -> unit
end;
structure File: FILE =
struct
(* system path representations *)
val platform_path = Path.implode o Path.expand;
fun shell_quote s =
if exists_string (fn c => c = "'") s then
error ("Illegal single quote in path specification: " ^ quote s)
else enclose "'" "'" s;
val shell_path = shell_quote o platform_path;
(* current working directory *)
val cd = cd o platform_path;
val pwd = Path.explode o pwd;
(* full_path *)
fun full_path dir path =
let
val path' = Path.expand path;
val _ = Path.is_current path' andalso error "Bad file specification";
val path'' = Path.append dir path';
in
if Path.is_absolute path'' then path''
else Path.append (pwd ()) path''
end;
(* tmp_path *)
fun tmp_path path =
Path.append (Path.variable "ISABELLE_TMP") (Path.base path);
(* directory entries *)
val exists = can OS.FileSys.modTime o platform_path;
val rm = OS.FileSys.remove o platform_path;
fun is_dir path =
the_default false (try OS.FileSys.isDir (platform_path path));
fun check_dir path =
if exists path andalso is_dir path then path
else error ("No such directory: " ^ Path.print path);
fun check_file path =
if exists path andalso not (is_dir path) then path
else error ("No such file: " ^ Path.print path);
(* open files *)
local
fun with_file open_file close_file f path =
let val file = open_file path
in Exn.release (Exn.capture f file before close_file file) end;
in
fun open_input f = with_file TextIO.openIn TextIO.closeIn f o platform_path;
fun open_output f = with_file TextIO.openOut TextIO.closeOut f o platform_path;
fun open_append f = with_file TextIO.openAppend TextIO.closeOut f o platform_path;
end;
(* input *)
(*scalable iterator -- avoid size limit of TextIO.inputAll, and overhead of many TextIO.inputLine*)
fun fold_lines f path a = open_input (fn file =>
let
fun read buf x =
(case TextIO.input file of
"" => (case Buffer.content buf of "" => x | line => f line x)
| input =>
(case String.fields (fn c => c = #"\n") input of
[rest] => read (Buffer.add rest buf) x
| line :: more => read_lines more (f (Buffer.content (Buffer.add line buf)) x)))
and read_lines [rest] x = read (Buffer.add rest Buffer.empty) x
| read_lines (line :: more) x = read_lines more (f line x);
in read Buffer.empty a end) path;
val read = open_input TextIO.inputAll;
(* output *)
fun output txts file = List.app (fn txt => TextIO.output (file, txt)) txts;
fun write_list path txts = open_output (output txts) path;
fun append_list path txts = open_append (output txts) path;
fun write path txt = write_list path [txt];
fun append path txt = append_list path [txt];
fun write_buffer path buf = open_output (Buffer.output buf) path;
(* copy *)
fun eq paths =
(case try (pairself (OS.FileSys.fileId o platform_path)) paths of
SOME ids => is_equal (OS.FileSys.compare ids)
| NONE => false);
fun copy src dst =
if eq (src, dst) then ()
else
let val target = if is_dir dst then Path.append dst (Path.base src) else dst
in write target (read src) end;
end;