File : a-direct.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- A D A . D I R E C T O R I E S --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 2004-2014, Free Software Foundation, Inc. --
10 -- --
11 -- This specification is derived for use with GNAT from AI-00248, which is --
12 -- expected to be a part of a future expected revised Ada Reference Manual. --
13 -- The copyright notice above, and the license provisions that follow apply --
14 -- solely to the contents of the part following the private keyword. --
15 -- --
16 -- GNAT is free software; you can redistribute it and/or modify it under --
17 -- terms of the GNU General Public License as published by the Free Soft- --
18 -- ware Foundation; either version 3, or (at your option) any later ver- --
19 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
20 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
21 -- or FITNESS FOR A PARTICULAR PURPOSE. --
22 -- --
23 -- --
24 -- --
25 -- --
26 -- --
27 -- You should have received a copy of the GNU General Public License and --
28 -- a copy of the GCC Runtime Library Exception along with this program; --
29 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
30 -- <http://www.gnu.org/licenses/>. --
31 -- --
32 -- GNAT was originally developed by the GNAT team at New York University. --
33 -- Extensive contributions were provided by Ada Core Technologies Inc. --
34 -- --
35 ------------------------------------------------------------------------------
36
37 -- Ada 2005: Implementation of Ada.Directories (AI95-00248). Note that this
38 -- unit is available without -gnat05. That seems reasonable, since you only
39 -- get it if you explicitly ask for it.
40
41 -- External files may be classified as directories, special files, or ordinary
42 -- files. A directory is an external file that is a container for files on
43 -- the target system. A special file is an external file that cannot be
44 -- created or read by a predefined Ada Input-Output package. External files
45 -- that are not special files or directories are called ordinary files.
46
47 -- A file name is a string identifying an external file. Similarly, a
48 -- directory name is a string identifying a directory. The interpretation of
49 -- file names and directory names is implementation-defined.
50
51 -- The full name of an external file is a full specification of the name of
52 -- the file. If the external environment allows alternative specifications of
53 -- the name (for example, abbreviations), the full name should not use such
54 -- alternatives. A full name typically will include the names of all of
55 -- directories that contain the item. The simple name of an external file is
56 -- the name of the item, not including any containing directory names. Unless
57 -- otherwise specified, a file name or directory name parameter to a
58 -- predefined Ada input-output subprogram can be a full name, a simple name,
59 -- or any other form of name supported by the implementation.
60
61 -- The default directory is the directory that is used if a directory or
62 -- file name is not a full name (that is, when the name does not fully
63 -- identify all of the containing directories).
64
65 -- A directory entry is a single item in a directory, identifying a single
66 -- external file (including directories and special files).
67
68 -- For each function that returns a string, the lower bound of the returned
69 -- value is 1.
70
71 with Ada.Calendar;
72 with Ada.Finalization;
73 with Ada.IO_Exceptions;
74 with Ada.Strings.Unbounded;
75
76 package Ada.Directories is
77
78 -----------------------------------
79 -- Directory and File Operations --
80 -----------------------------------
81
82 function Current_Directory return String;
83 -- Returns the full directory name for the current default directory. The
84 -- name returned must be suitable for a future call to Set_Directory.
85 -- The exception Use_Error is propagated if a default directory is not
86 -- supported by the external environment.
87
88 procedure Set_Directory (Directory : String);
89 -- Sets the current default directory. The exception Name_Error is
90 -- propagated if the string given as Directory does not identify an
91 -- existing directory. The exception Use_Error is propagated if the
92 -- external environment does not support making Directory (in the absence
93 -- of Name_Error) a default directory.
94
95 procedure Create_Directory
96 (New_Directory : String;
97 Form : String := "");
98 -- Creates a directory with name New_Directory. The Form parameter can be
99 -- used to give system-dependent characteristics of the directory; the
100 -- interpretation of the Form parameter is implementation-defined. A null
101 -- string for Form specifies the use of the default options of the
102 -- implementation of the new directory. The exception Name_Error is
103 -- propagated if the string given as New_Directory does not allow the
104 -- identification of a directory. The exception Use_Error is propagated if
105 -- the external environment does not support the creation of a directory
106 -- with the given name (in the absence of Name_Error) and form.
107 --
108 -- The Form parameter is ignored
109
110 procedure Delete_Directory (Directory : String);
111 -- Deletes an existing empty directory with name Directory. The exception
112 -- Name_Error is propagated if the string given as Directory does not
113 -- identify an existing directory. The exception Use_Error is propagated
114 -- if the external environment does not support the deletion of the
115 -- directory (or some portion of its contents) with the given name (in the
116 -- absence of Name_Error).
117
118 procedure Create_Path
119 (New_Directory : String;
120 Form : String := "");
121 -- Creates zero or more directories with name New_Directory. Each
122 -- non-existent directory named by New_Directory is created. For example,
123 -- on a typical Unix system, Create_Path ("/usr/me/my"); would create
124 -- directory "me" in directory "usr", then create directory "my"
125 -- in directory "me". The Form can be used to give system-dependent
126 -- characteristics of the directory; the interpretation of the Form
127 -- parameter is implementation-defined. A null string for Form specifies
128 -- the use of the default options of the implementation of the new
129 -- directory. The exception Name_Error is propagated if the string given
130 -- as New_Directory does not allow the identification of any directory. The
131 -- exception Use_Error is propagated if the external environment does not
132 -- support the creation of any directories with the given name (in the
133 -- absence of Name_Error) and form.
134 --
135 -- The Form parameter is ignored
136
137 procedure Delete_Tree (Directory : String);
138 -- Deletes an existing directory with name Directory. The directory and
139 -- all of its contents (possibly including other directories) are deleted.
140 -- The exception Name_Error is propagated if the string given as Directory
141 -- does not identify an existing directory. The exception Use_Error is
142 -- propagated if the external environment does not support the deletion
143 -- of the directory or some portion of its contents with the given name
144 -- (in the absence of Name_Error). If Use_Error is propagated, it is
145 -- unspecified if a portion of the contents of the directory are deleted.
146
147 procedure Delete_File (Name : String);
148 -- Deletes an existing ordinary or special file with Name. The exception
149 -- Name_Error is propagated if the string given as Name does not identify
150 -- an existing ordinary or special external file. The exception Use_Error
151 -- is propagated if the external environment does not support the deletion
152 -- of the file with the given name (in the absence of Name_Error).
153
154 procedure Rename (Old_Name, New_Name : String);
155 -- Renames an existing external file (including directories) with Old_Name
156 -- to New_Name. The exception Name_Error is propagated if the string given
157 -- as Old_Name does not identify an existing external file. The exception
158 -- Use_Error is propagated if the external environment does not support the
159 -- renaming of the file with the given name (in the absence of Name_Error).
160 -- In particular, Use_Error is propagated if a file or directory already
161 -- exists with New_Name.
162
163 procedure Copy_File
164 (Source_Name : String;
165 Target_Name : String;
166 Form : String := "");
167 -- Copies the contents of the existing external file with Source_Name to
168 -- Target_Name. The resulting external file is a duplicate of the source
169 -- external file. The Form argument can be used to give system-dependent
170 -- characteristics of the resulting external file; the interpretation of
171 -- the Form parameter is implementation-defined. Exception Name_Error is
172 -- propagated if the string given as Source_Name does not identify an
173 -- existing external ordinary or special file or if the string given as
174 -- Target_Name does not allow the identification of an external file. The
175 -- exception Use_Error is propagated if the external environment does not
176 -- support the creating of the file with the name given by Target_Name and
177 -- form given by Form, or copying of the file with the name given by
178 -- Source_Name (in the absence of Name_Error).
179 --
180 -- Interpretation of the Form parameter:
181 --
182 -- The Form parameter is case-insensitive
183 --
184 -- Two fields are recognized in the Form parameter:
185 -- preserve=<value>
186 -- mode=<value>
187 --
188 -- <value> starts immediately after the character '=' and ends with the
189 -- character immediately preceding the next comma (',') or with the
190 -- last character of the parameter.
191 --
192 -- The allowed values for preserve= are:
193 --
194 -- no_attributes: Do not try to preserve any file attributes. This
195 -- is the default if no preserve= is found in Form.
196 --
197 -- all_attributes: Try to preserve all file attributes (timestamps,
198 -- access rights).
199 --
200 -- timestamps: Preserve the timestamp of the copied file, but not
201 -- the other file attributes.
202 --
203 -- The allowed values for mode= are:
204 --
205 -- copy: Only copy if the destination file does not already
206 -- exist. If it already exists, Copy_File will fail.
207 --
208 -- overwrite: Copy the file in all cases. Overwrite an already
209 -- existing destination file. This is the default if
210 -- no mode= is found in Form.
211 --
212 -- append: Append the original file to the destination file.
213 -- If the destination file does not exist, the
214 -- destination file is a copy of the source file.
215 -- When mode=append, the field preserve=, if it
216 -- exists, is not taken into account.
217 --
218 -- If the Form parameter includes one or both of the fields and the value
219 -- or values are incorrect, Copy_File fails with Use_Error.
220 --
221 -- Examples of correct Forms:
222 -- Form => "preserve=no_attributes,mode=overwrite" (the default)
223 -- Form => "mode=append"
224 -- Form => "mode=copy,preserve=all_attributes"
225 --
226 -- Examples of incorrect Forms:
227 -- Form => "preserve=junk"
228 -- Form => "mode=internal,preserve=timestamps"
229
230 ----------------------------------------
231 -- File and directory name operations --
232 ----------------------------------------
233
234 function Full_Name (Name : String) return String;
235 -- Returns the full name corresponding to the file name specified by Name.
236 -- The exception Name_Error is propagated if the string given as Name does
237 -- not allow the identification of an external file (including directories
238 -- and special files).
239
240 function Simple_Name (Name : String) return String;
241 -- Returns the simple name portion of the file name specified by Name. The
242 -- exception Name_Error is propagated if the string given as Name does not
243 -- allow the identification of an external file (including directories and
244 -- special files).
245
246 function Containing_Directory (Name : String) return String;
247 -- Returns the name of the containing directory of the external file
248 -- (including directories) identified by Name. If more than one directory
249 -- can contain Name, the directory name returned is implementation-defined.
250 -- The exception Name_Error is propagated if the string given as Name does
251 -- not allow the identification of an external file. The exception
252 -- Use_Error is propagated if the external file does not have a containing
253 -- directory.
254
255 function Extension (Name : String) return String;
256 -- Returns the extension name corresponding to Name. The extension name is
257 -- a portion of a simple name (not including any separator characters),
258 -- typically used to identify the file class. If the external environment
259 -- does not have extension names, then the null string is returned.
260 -- The exception Name_Error is propagated if the string given as Name does
261 -- not allow the identification of an external file.
262
263 function Base_Name (Name : String) return String;
264 -- Returns the base name corresponding to Name. The base name is the
265 -- remainder of a simple name after removing any extension and extension
266 -- separators. The exception Name_Error is propagated if the string given
267 -- as Name does not allow the identification of an external file
268 -- (including directories and special files).
269
270 function Compose
271 (Containing_Directory : String := "";
272 Name : String;
273 Extension : String := "") return String;
274 -- Returns the name of the external file with the specified
275 -- Containing_Directory, Name, and Extension. If Extension is the null
276 -- string, then Name is interpreted as a simple name; otherwise Name is
277 -- interpreted as a base name. The exception Name_Error is propagated if
278 -- the string given as Containing_Directory is not null and does not allow
279 -- the identification of a directory, or if the string given as Extension
280 -- is not null and is not a possible extension, or if the string given as
281 -- Name is not a possible simple name (if Extension is null) or base name
282 -- (if Extension is non-null).
283
284 --------------------------------
285 -- File and directory queries --
286 --------------------------------
287
288 type File_Kind is (Directory, Ordinary_File, Special_File);
289 -- The type File_Kind represents the kind of file represented by an
290 -- external file or directory.
291
292 type File_Size is range 0 .. Long_Long_Integer'Last;
293 -- The type File_Size represents the size of an external file
294
295 function Exists (Name : String) return Boolean;
296 -- Returns True if external file represented by Name exists, and False
297 -- otherwise. The exception Name_Error is propagated if the string given as
298 -- Name does not allow the identification of an external file (including
299 -- directories and special files).
300
301 function Kind (Name : String) return File_Kind;
302 -- Returns the kind of external file represented by Name. The exception
303 -- Name_Error is propagated if the string given as Name does not allow the
304 -- identification of an existing external file.
305
306 function Size (Name : String) return File_Size;
307 -- Returns the size of the external file represented by Name. The size of
308 -- an external file is the number of stream elements contained in the file.
309 -- If the external file is discontiguous (not all elements exist), the
310 -- result is implementation-defined. If the external file is not an
311 -- ordinary file, the result is implementation-defined. The exception
312 -- Name_Error is propagated if the string given as Name does not allow the
313 -- identification of an existing external file. The exception
314 -- Constraint_Error is propagated if the file size is not a value of type
315 -- File_Size.
316
317 function Modification_Time (Name : String) return Ada.Calendar.Time;
318 -- Returns the time that the external file represented by Name was most
319 -- recently modified. If the external file is not an ordinary file, the
320 -- result is implementation-defined. The exception Name_Error is propagated
321 -- if the string given as Name does not allow the identification of an
322 -- existing external file. The exception Use_Error is propagated if the
323 -- external environment does not support the reading the modification time
324 -- of the file with the name given by Name (in the absence of Name_Error).
325
326 -------------------------
327 -- Directory Searching --
328 -------------------------
329
330 type Directory_Entry_Type is limited private;
331 -- The type Directory_Entry_Type represents a single item in a directory.
332 -- These items can only be created by the Get_Next_Entry procedure in this
333 -- package. Information about the item can be obtained from the functions
334 -- declared in this package. A default initialized object of this type is
335 -- invalid; objects returned from Get_Next_Entry are valid.
336
337 type Filter_Type is array (File_Kind) of Boolean;
338 -- The type Filter_Type specifies which directory entries are provided from
339 -- a search operation. If the Directory component is True, directory
340 -- entries representing directories are provided. If the Ordinary_File
341 -- component is True, directory entries representing ordinary files are
342 -- provided. If the Special_File component is True, directory entries
343 -- representing special files are provided.
344
345 type Search_Type is limited private;
346 -- The type Search_Type contains the state of a directory search. A
347 -- default-initialized Search_Type object has no entries available
348 -- (More_Entries returns False).
349
350 procedure Start_Search
351 (Search : in out Search_Type;
352 Directory : String;
353 Pattern : String;
354 Filter : Filter_Type := (others => True));
355 -- Starts a search in the directory entry in the directory named by
356 -- Directory for entries matching Pattern. Pattern represents a file name
357 -- matching pattern. If Pattern is null, all items in the directory are
358 -- matched; otherwise, the interpretation of Pattern is implementation-
359 -- defined. Only items which match Filter will be returned. After a
360 -- successful call on Start_Search, the object Search may have entries
361 -- available, but it may have no entries available if no files or
362 -- directories match Pattern and Filter. The exception Name_Error is
363 -- propagated if the string given by Directory does not identify an
364 -- existing directory, or if Pattern does not allow the identification of
365 -- any possible external file or directory. The exception Use_Error is
366 -- propagated if the external environment does not support the searching
367 -- of the directory with the given name (in the absence of Name_Error).
368
369 procedure End_Search (Search : in out Search_Type);
370 -- Ends the search represented by Search. After a successful call on
371 -- End_Search, the object Search will have no entries available. Note
372 -- that it is not necessary to call End_Search if the call to Start_Search
373 -- was unsuccessful and raised an exception (but it is harmless to make
374 -- the call in this case).
375
376 function More_Entries (Search : Search_Type) return Boolean;
377 -- Returns True if more entries are available to be returned by a call
378 -- to Get_Next_Entry for the specified search object, and False otherwise.
379
380 procedure Get_Next_Entry
381 (Search : in out Search_Type;
382 Directory_Entry : out Directory_Entry_Type);
383 -- Returns the next Directory_Entry for the search described by Search that
384 -- matches the pattern and filter. If no further matches are available,
385 -- Status_Error is raised. It is implementation-defined as to whether the
386 -- results returned by this routine are altered if the contents of the
387 -- directory are altered while the Search object is valid (for example, by
388 -- another program). The exception Use_Error is propagated if the external
389 -- environment does not support continued searching of the directory
390 -- represented by Search.
391
392 procedure Search
393 (Directory : String;
394 Pattern : String;
395 Filter : Filter_Type := (others => True);
396 Process : not null access procedure
397 (Directory_Entry : Directory_Entry_Type));
398 -- Searches in the directory named by Directory for entries matching
399 -- Pattern. The subprogram designated by Process is called with each
400 -- matching entry in turn. Pattern represents a pattern for matching file
401 -- names. If Pattern is null, all items in the directory are matched;
402 -- otherwise, the interpretation of Pattern is implementation-defined.
403 -- Only items that match Filter will be returned. The exception Name_Error
404 -- is propagated if the string given by Directory does not identify
405 -- an existing directory, or if Pattern does not allow the identification
406 -- of any possible external file or directory. The exception Use_Error is
407 -- propagated if the external environment does not support the searching
408 -- of the directory with the given name (in the absence of Name_Error).
409
410 -------------------------------------
411 -- Operations on Directory Entries --
412 -------------------------------------
413
414 function Simple_Name (Directory_Entry : Directory_Entry_Type) return String;
415 -- Returns the simple external name of the external file (including
416 -- directories) represented by Directory_Entry. The format of the name
417 -- returned is implementation-defined. The exception Status_Error is
418 -- propagated if Directory_Entry is invalid.
419
420 function Full_Name (Directory_Entry : Directory_Entry_Type) return String;
421 -- Returns the full external name of the external file (including
422 -- directories) represented by Directory_Entry. The format of the name
423 -- returned is implementation-defined. The exception Status_Error is
424 -- propagated if Directory_Entry is invalid.
425
426 function Kind (Directory_Entry : Directory_Entry_Type) return File_Kind;
427 -- Returns the kind of external file represented by Directory_Entry. The
428 -- exception Status_Error is propagated if Directory_Entry is invalid.
429
430 function Size (Directory_Entry : Directory_Entry_Type) return File_Size;
431 -- Returns the size of the external file represented by Directory_Entry.
432 -- The size of an external file is the number of stream elements contained
433 -- in the file. If the external file is discontiguous (not all elements
434 -- exist), the result is implementation-defined. If the external file
435 -- represented by Directory_Entry is not an ordinary file, the result is
436 -- implementation-defined. The exception Status_Error is propagated if
437 -- Directory_Entry is invalid. The exception Constraint_Error is propagated
438 -- if the file size is not a value of type File_Size.
439
440 function Modification_Time
441 (Directory_Entry : Directory_Entry_Type) return Ada.Calendar.Time;
442 -- Returns the time that the external file represented by Directory_Entry
443 -- was most recently modified. If the external file represented by
444 -- Directory_Entry is not an ordinary file, the result is
445 -- implementation-defined. The exception Status_Error is propagated if
446 -- Directory_Entry is invalid. The exception Use_Error is propagated if
447 -- the external environment does not support the reading the modification
448 -- time of the file represented by Directory_Entry.
449
450 ----------------
451 -- Exceptions --
452 ----------------
453
454 Status_Error : exception renames Ada.IO_Exceptions.Status_Error;
455 Name_Error : exception renames Ada.IO_Exceptions.Name_Error;
456 Use_Error : exception renames Ada.IO_Exceptions.Use_Error;
457 Device_Error : exception renames Ada.IO_Exceptions.Device_Error;
458
459 private
460 type Directory_Entry_Type is record
461 Is_Valid : Boolean := False;
462 Simple : Ada.Strings.Unbounded.Unbounded_String;
463 Full : Ada.Strings.Unbounded.Unbounded_String;
464 Kind : File_Kind := Ordinary_File;
465 end record;
466
467 -- The type Search_Data is defined in the body, so that the spec does not
468 -- depend on packages of the GNAT hierarchy.
469
470 type Search_Data;
471 type Search_Ptr is access Search_Data;
472
473 -- Search_Type need to be a controlled type, because it includes component
474 -- of type Dir_Type (in GNAT.Directory_Operations) that need to be closed
475 -- (if opened) during finalization. The component need to be an access
476 -- value, because Search_Data is not fully defined in the spec.
477
478 type Search_Type is new Ada.Finalization.Controlled with record
479 Value : Search_Ptr;
480 end record;
481
482 procedure Finalize (Search : in out Search_Type);
483 -- Close the directory, if opened, and deallocate Value
484
485 procedure End_Search (Search : in out Search_Type) renames Finalize;
486
487 end Ada.Directories;