------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- G N A T . O S _ L I B -- -- -- -- S p e c -- -- -- -- $Revision: 1.1.1.2 $ -- -- -- Copyright (C) 1995-2001 Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 2, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com). -- -- -- ------------------------------------------------------------------------------ -- Operating system interface facilities -- This package contains types and procedures for interfacing to the -- underlying OS. It is used by the GNAT compiler and by tools associated -- with the GNAT compiler, and therefore works for the various operating -- systems to which GNAT has been ported. This package will undoubtedly -- grow as new services are needed by various tools. -- This package tends to use fairly low-level Ada in order to not bring -- in large portions of the RTL. For example, functions return access -- to string as part of avoiding functions returning unconstrained types; -- types related to dates are defined here instead of using the types -- from Calendar, since use of Calendar forces linking in of tasking code. -- Except where specifically noted, these routines are portable across -- all GNAT implementations on all supported operating systems. with System; with Unchecked_Deallocation; package GNAT.OS_Lib is pragma Elaborate_Body (OS_Lib); type String_Access is access all String; -- General purpose string access type procedure Free is new Unchecked_Deallocation (Object => String, Name => String_Access); type String_List is array (Positive range <>) of String_Access; type String_List_Access is access all String_List; -- General purpose array and pointer for list of string accesses --------------------- -- Time/Date Stuff -- --------------------- -- The OS's notion of time is represented by the private type OS_Time. -- This is the type returned by the File_Time_Stamp functions to obtain -- the time stamp of a specified file. Functions and a procedure (modeled -- after the similar subprograms in package Calendar) are provided for -- extracting information from a value of this type. Although these are -- called GM, the intention is not that they provide GMT times in all -- cases but rather the actual (time-zone independent) time stamp of the -- file (of course in Unix systems, this *is* in GMT form). type OS_Time is private; subtype Year_Type is Integer range 1900 .. 2099; subtype Month_Type is Integer range 1 .. 12; subtype Day_Type is Integer range 1 .. 31; subtype Hour_Type is Integer range 0 .. 23; subtype Minute_Type is Integer range 0 .. 59; subtype Second_Type is Integer range 0 .. 59; function GM_Year (Date : OS_Time) return Year_Type; function GM_Month (Date : OS_Time) return Month_Type; function GM_Day (Date : OS_Time) return Day_Type; function GM_Hour (Date : OS_Time) return Hour_Type; function GM_Minute (Date : OS_Time) return Minute_Type; function GM_Second (Date : OS_Time) return Second_Type; procedure GM_Split (Date : OS_Time; Year : out Year_Type; Month : out Month_Type; Day : out Day_Type; Hour : out Hour_Type; Minute : out Minute_Type; Second : out Second_Type); ---------------- -- File Stuff -- ---------------- -- These routines give access to the open/creat/close/read/write level -- of I/O routines in the typical C library (these functions are not -- part of the ANSI C standard, but are typically available in all -- systems). See also package Interfaces.C_Streams for access to the -- stream level routines. -- Note on file names. If a file name is passed as type String in any -- of the following specifications, then the name is a normal Ada string -- and need not be NUL-terminated. However, a trailing NUL character is -- permitted, and will be ignored (more accurately, the NUL and any -- characters that follow it will be ignored). type File_Descriptor is private; -- Corresponds to the int file handle values used in the C routines, Standin : constant File_Descriptor; Standout : constant File_Descriptor; Standerr : constant File_Descriptor; -- File descriptors for standard input output files Invalid_FD : constant File_Descriptor; -- File descriptor returned when error in opening/creating file; type Mode is (Binary, Text); for Mode'Size use Integer'Size; for Mode use (Binary => 0, Text => 1); -- Used in all the Open and Create calls to specify if the file is to be -- opened in binary mode or text mode. In systems like Unix, this has no -- effect, but in systems capable of text mode translation, the use of -- Text as the mode parameter causes the system to do CR/LF translation -- and also to recognize the DOS end of file character on input. The use -- of Text where appropriate allows programs to take a portable Unix view -- of DOs-format files and process them appropriately. function Open_Read (Name : String; Fmode : Mode) return File_Descriptor; -- Open file Name for reading, returning file descriptor File descriptor -- returned is Invalid_FD if file cannot be opened. function Open_Read_Write (Name : String; Fmode : Mode) return File_Descriptor; -- Open file Name for both reading and writing, returning file -- descriptor. File descriptor returned is Invalid_FD if file cannot be -- opened. function Create_File (Name : String; Fmode : Mode) return File_Descriptor; -- Creates new file with given name for writing, returning file descriptor -- for subsequent use in Write calls. File descriptor returned is -- Invalid_FD if file cannot be successfully created function Create_New_File (Name : String; Fmode : Mode) return File_Descriptor; -- Create new file with given name for writing, returning file descriptor -- for subsequent use in Write calls. This differs from Create_File in -- that it fails if the file already exists. File descriptor returned is -- Invalid_FD if the file exists or cannot be created. Temp_File_Len : constant Integer := 12; -- Length of name returned by Create_Temp_File call (GNAT-XXXXXX & NUL) subtype Temp_File_Name is String (1 .. Temp_File_Len); -- String subtype set by Create_Temp_File procedure Create_Temp_File (FD : out File_Descriptor; Name : out Temp_File_Name); -- Create and open for writing a temporary file. The name of the -- file and the File Descriptor are returned. The File Descriptor -- returned is Invalid_FD in the case of failure. No mode parameter -- is provided. Since this is a temporary file, there is no point in -- doing text translation on it. procedure Close (FD : File_Descriptor); pragma Import (C, Close, "close"); -- Close file referenced by FD procedure Delete_File (Name : String; Success : out Boolean); -- Deletes file. Success is set True or False indicating if the delete is -- successful. procedure Rename_File (Old_Name : String; New_Name : String; Success : out Boolean); -- Rename a file. Successis set True or False indicating if the rename is -- successful. function Read (FD : File_Descriptor; A : System.Address; N : Integer) return Integer; pragma Import (C, Read, "read"); -- Read N bytes to address A from file referenced by FD. Returned value -- is count of bytes actually read, which can be less than N at EOF. function Write (FD : File_Descriptor; A : System.Address; N : Integer) return Integer; pragma Import (C, Write, "write"); -- Write N bytes from address A to file referenced by FD. The returned -- value is the number of bytes written, which can be less than N if -- a disk full condition was detected. Seek_Cur : constant := 1; Seek_End : constant := 2; Seek_Set : constant := 0; -- Used to indicate origin for Lseek call procedure Lseek (FD : File_Descriptor; offset : Long_Integer; origin : Integer); pragma Import (C, Lseek, "lseek"); -- Sets the current file pointer to the indicated offset value, -- relative to the current position (origin = SEEK_CUR), end of -- file (origin = SEEK_END), or start of file (origin = SEEK_SET). function File_Length (FD : File_Descriptor) return Long_Integer; pragma Import (C, File_Length, "__gnat_file_length"); -- Get length of file from file descriptor FD function File_Time_Stamp (Name : String) return OS_Time; -- Given the name of a file or directory, Name, obtains and returns the -- time stamp. This function can be used for an unopend file. function File_Time_Stamp (FD : File_Descriptor) return OS_Time; -- Get time stamp of file from file descriptor FD function Normalize_Pathname (Name : String; Directory : String := "") return String; -- Returns a file name as an absolute path name, resolving all relative -- directories, and symbolic links. The parameter Directory is a fully -- resolved path name for a directory, or the empty string (the default). -- Name is the name of a file, which is either relative to the given -- directory name, if Directory is non-null, or to the current working -- directory if Directory is null. The result returned is the normalized -- name of the file. For most cases, if two file names designate the same -- file through different paths, Normalize_Pathname will return the same -- canonical name in both cases. However, there are cases when this is -- not true; for example, this is not true in Unix for two hard links -- designating the same file. -- -- If Name cannot be resolved or is null on entry (for example if there is -- a circularity in symbolic links: A is a symbolic link for B, while B is -- a symbolic link for A), then Normalize_Pathname returns an empty string. -- -- In VMS, if Name follows the VMS syntax file specification, it is first -- converted into Unix syntax. If the conversion fails, Normalize_Pathname -- returns an empty string. function Is_Absolute_Path (Name : String) return Boolean; -- Returns True if Name is an absolute path name, i.e. it designates -- a directory absolutely, rather than relative to another directory. function Is_Regular_File (Name : String) return Boolean; -- Determines if the given string, Name, is the name of an existing -- regular file. Returns True if so, False otherwise. function Is_Directory (Name : String) return Boolean; -- Determines if the given string, Name, is the name of a directory. -- Returns True if so, False otherwise. function Is_Writable_File (Name : String) return Boolean; -- Determines if the given string, Name, is the name of an existing -- file that is writable. Returns True if so, False otherwise. function Locate_Exec_On_Path (Exec_Name : String) return String_Access; -- Try to locate an executable whose name is given by Exec_Name in the -- directories listed in the environment Path. If the Exec_Name doesn't -- have the executable suffix, it will be appended before the search. -- Otherwise works like Locate_Regular_File below. -- -- Note that this function allocates some memory for the returned value. -- This memory needs to be deallocated after use. function Locate_Regular_File (File_Name : String; Path : String) return String_Access; -- Try to locate a regular file whose name is given by File_Name in the -- directories listed in Path. If a file is found, its full pathname is -- returned; otherwise, a null pointer is returned. If the File_Name given -- is an absolute pathname, then Locate_Regular_File just checks that the -- file exists and is a regular file. Otherwise, the Path argument is -- parsed according to OS conventions, and for each directory in the Path -- a check is made if File_Name is a relative pathname of a regular file -- from that directory. -- -- Note that this function allocates some memory for the returned value. -- This memory needs to be deallocated after use. function Get_Debuggable_Suffix return String_Access; -- Return the debuggable suffix convention. Usually this is the same as -- the convention for Get_Executable_Suffix. -- -- Note that this function allocates some memory for the returned value. -- This memory needs to be deallocated after use. function Get_Executable_Suffix return String_Access; -- Return the executable suffix convention. -- -- Note that this function allocates some memory for the returned value. -- This memory needs to be deallocated after use. function Get_Object_Suffix return String_Access; -- Return the object suffix convention. -- -- Note that this function allocates some memory for the returned value. -- This memory needs to be deallocated after use. -- The following section contains low-level routines using addresses to -- pass file name and executable name. In each routine the name must be -- Nul-Terminated. For complete documentation refer to the equivalent -- routine (but using string) defined above. subtype C_File_Name is System.Address; -- This subtype is used to document that a parameter is the address -- of a null-terminated string containing the name of a file. function Open_Read (Name : C_File_Name; Fmode : Mode) return File_Descriptor; function Open_Read_Write (Name : C_File_Name; Fmode : Mode) return File_Descriptor; function Create_File (Name : C_File_Name; Fmode : Mode) return File_Descriptor; function Create_New_File (Name : C_File_Name; Fmode : Mode) return File_Descriptor; procedure Delete_File (Name : C_File_Name; Success : out Boolean); procedure Rename_File (Old_Name : C_File_Name; New_Name : C_File_Name; Success : out Boolean); function File_Time_Stamp (Name : C_File_Name) return OS_Time; function Is_Regular_File (Name : C_File_Name) return Boolean; function Is_Directory (Name : C_File_Name) return Boolean; function Is_Writable_File (Name : C_File_Name) return Boolean; function Locate_Regular_File (File_Name : C_File_Name; Path : C_File_Name) return String_Access; ------------------ -- Subprocesses -- ------------------ subtype Argument_List is String_List; -- Type used for argument list in call to Spawn. The lower bound -- of the array should be 1, and the length of the array indicates -- the number of arguments. subtype Argument_List_Access is String_List_Access; -- Type used to return an Argument_List without dragging in secondary -- stack. procedure Spawn (Program_Name : String; Args : Argument_List; Success : out Boolean); -- The first parameter of function Spawn is the name of the executable. -- The second parameter contains the arguments to be passed to the -- program. Success is False if the named program could not be spawned -- or its execution completed unsuccessfully. Note that the caller will -- be blocked until the execution of the spawned program is complete. -- For maximum portability, use a full path name for the Program_Name -- argument. On some systems (notably Unix systems) a simple file -- name may also work (if the executable can be located in the path). -- -- Note: Arguments that contain spaces and/or quotes such as -- "--GCC=gcc -v" or "--GCC=""gcc-v""" are not portable -- across OSes. They may or may not have the desired effect. function Spawn (Program_Name : String; Args : Argument_List) return Integer; -- Like above, but as function returning the exact exit status type Process_Id is private; -- A private type used to identify a process activated by the following -- non-blocking call. The only meaningful operation on this type is a -- comparison for equality. Invalid_Pid : constant Process_Id; -- A special value used to indicate errors, as described below. function Non_Blocking_Spawn (Program_Name : String; Args : Argument_List) return Process_Id; -- This is a non blocking call. The Process_Id of the spawned process -- is returned. Parameters are to be used as in Spawn. If Invalid_Id -- is returned the program could not be spawned. procedure Wait_Process (Pid : out Process_Id; Success : out Boolean); -- Wait for the completion of any of the processes created by previous -- calls to Non_Blocking_Spawn. The caller will be suspended until one -- of these processes terminates (normally or abnormally). If any of -- these subprocesses terminates prior to the call to Wait_Process (and -- has not been returned by a previous call to Wait_Process), then the -- call to Wait_Process is immediate. Pid identifies the process that -- has terminated (matching the value returned from Non_Blocking_Spawn). -- Success is set to True if this sub-process terminated successfully. -- If Pid = Invalid_Id, there were no subprocesses left to wait on. function Argument_String_To_List (Arg_String : String) return Argument_List_Access; -- Take a string that is a program and it's arguments and parse it into -- an Argument_List. ------------------- -- Miscellaneous -- ------------------- function Getenv (Name : String) return String_Access; -- Get the value of the environment variable. Returns an access -- to the empty string if the environment variable does not exist -- or has an explicit null value (in some operating systems these -- are distinct cases, in others they are not; this interface -- abstracts away that difference. procedure Setenv (Name : String; Value : String); -- Set the value of the environment variable Name to Value. This call -- modifies the current environment, but does not modify the parent -- process environment. After a call to Setenv, Getenv (Name) will -- always return a String_Access referencing the same String as Value. -- This is true also for the null string case (the actual effect may -- be to either set an explicit null as the value, or to remove the -- entry, this is operating system dependent). Note that any following -- calls to Spawn will pass an environment to the spawned process that -- includes the changes made by Setenv calls. This procedure is not -- available under VMS. procedure OS_Exit (Status : Integer); pragma Import (C, OS_Exit, "__gnat_os_exit"); -- Exit to OS with given status code (program is terminated) procedure OS_Abort; pragma Import (C, OS_Abort, "abort"); -- Exit to OS signalling an abort (traceback or other appropriate -- diagnostic information should be given if possible, or entry made -- to the debugger if that is possible). function Errno return Integer; pragma Import (C, Errno, "__get_errno"); -- Return the task-safe last error number. procedure Set_Errno (Errno : Integer); pragma Import (C, Set_Errno, "__set_errno"); -- Set the task-safe error number. Directory_Separator : constant Character; -- The character that is used to separate parts of a pathname. Path_Separator : constant Character; -- The character to separate paths in an environment variable value. private pragma Import (C, Path_Separator, "__gnat_path_separator"); pragma Import (C, Directory_Separator, "__gnat_dir_separator"); type OS_Time is new Integer; type File_Descriptor is new Integer; Standin : constant File_Descriptor := 0; Standout : constant File_Descriptor := 1; Standerr : constant File_Descriptor := 2; Invalid_FD : constant File_Descriptor := -1; type Process_Id is new Integer; Invalid_Pid : constant Process_Id := -1; end GNAT.OS_Lib;