home *** CD-ROM | disk | FTP | other *** search
- ------------------------------------------------------------------------------
- -- --
- -- GNAT COMPILER COMPONENTS --
- -- --
- -- I N T E R F A C E S . C _ S T R E A M S --
- -- --
- -- S p e c --
- -- --
- -- $Revision: 1.8 $ --
- -- --
- -- The GNAT library is free software; you can redistribute it and/or modify --
- -- it under terms of the GNU Library General Public License as published by --
- -- the Free Software Foundation; either version 2, or (at your option) any --
- -- later version. The GNAT library is distributed in the hope that it will --
- -- be useful, but WITHOUT ANY WARRANTY; without even the implied warranty --
- -- of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU --
- -- Library General Public License for more details. You should have --
- -- received a copy of the GNU Library General Public License along with --
- -- the GNAT library; see the file COPYING.LIB. If not, write to the Free --
- -- Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. --
- -- --
- ------------------------------------------------------------------------------
-
- -- This package is a thin binding to selected functions in the C
- -- library that provide a complete interface for handling C streams.
-
- with Unchecked_Conversion;
- with System;
-
- package Interfaces.C_Streams is
-
- -- Note: the reason we do not use the types that are in Interfaces.C is
- -- that we want to avoid dragging in the code in this unit if possible.
-
- subtype chars is System.Address;
- -- Pointer to null-terminated array of characters
-
- subtype FILEs is System.Address;
- -- Corresponds to the C type FILE*
-
- subtype voids is System.Address;
- -- Corresponds to the C type void*
-
- subtype int is Integer;
- subtype long is Long_Integer;
-
- -- Note: the above types are subtypes deliberately, and it is part of
- -- this spec that the above correspondences are guaranteed. This means
- -- that it is legitimate to, for example, use Integer instead of int.
- -- We provide these synonyms for clarity, but in some cases it may be
- -- convenient to use the underlying types (for example to avoid an
- -- unnecessary dependency of a spec on the spec of this unit).
-
- type size_t is mod 2 ** Standard'Address_Size;
-
- NULL_Stream : constant FILEs;
- -- Value returned (NULL in C) to indicate an fdopen/fopen/tmpfile error
-
- ----------------------------------
- -- Constants Defined in stdio.h --
- ----------------------------------
-
- EOF : constant int;
- -- Used by a number of routines to indicate error or end of file
-
- IOFBF : constant int;
- IOLBF : constant int;
- IONBF : constant int;
- -- Used to indicate buffering mode for setvbuf call
-
- SEEK_CUR : constant int;
- SEEK_END : constant int;
- SEEK_SET : constant int;
- -- Used to indicate origin for fseek call
-
- function stdin return FILEs;
- function stdout return FILEs;
- function stderr return FILEs;
- -- Streams associated with standard files
-
- --------------------------
- -- Standard C functions --
- --------------------------
-
- -- The functions selected below are ones that are available in DOS,
- -- OS/2, UNIX and Xenix (but not necessarily in ANSI C). These are
- -- very thin interfaces which copy exactly the C headers. For more
- -- documentation on these functions, see the Microsoft C "Run-Time
- -- Library Reference" (Microsoft Press, 1990, ISBN 1-55615-225-6),
- -- which includes useful information on system compatibility.
-
- procedure clearerr (stream : FILEs);
-
- function fclose (stream : FILEs) return int;
-
- function fdopen (handle : int; mode : chars) return FILEs;
-
- function feof (stream : FILEs) return int;
-
- function ferror (stream : FILEs) return int;
-
- function fflush (stream : FILEs) return int;
-
- function fgetc (stream : FILEs) return int;
-
- function fgets (strng : chars; n : int; stream : FILEs) return chars;
-
- function fileno (stream : FILEs) return int;
-
- function fopen (filename : chars; Mode : chars) return FILEs;
- -- Note: to maintain target independence, use text_translation_required,
- -- a boolean variable defined in a-sysdep.c to deal with the target
- -- dependent text translation requirement. If this variable is set,
- -- then b/t should be appended to the standard mode argument to set
- -- the text translation mode off or on as required.
-
- function fputc (C : int; stream : FILEs) return int;
-
- function fputs (Strng : chars; Stream : FILEs) return int;
-
- function fread
- (buffer : voids;
- size : size_t;
- count : size_t;
- stream : FILEs)
- return size_t;
-
- function freopen
- (filename : chars;
- mode : chars;
- stream : FILEs)
- return FILEs;
-
- function fseek
- (stream : FILEs;
- offset : long;
- origin : int)
- return int;
-
- function ftell (stream : FILEs) return long;
-
- function fwrite
- (buffer : voids;
- size : size_t;
- count : size_t;
- stream : FILEs)
- return size_t;
-
- function isatty (handle : int) return int;
-
- procedure mktemp (template : chars);
- -- The return value (which is just a pointer to template) is discarded
-
- procedure rewind (stream : FILEs);
-
- function rmtmp return int;
-
- function setvbuf
- (stream : FILEs;
- buffer : chars;
- mode : int;
- size : size_t)
- return int;
-
- function tmpfile return FILEs;
-
- function ungetc (c : int; stream : FILEs) return int;
-
- function unlink (filename : chars) return int;
-
- ---------------------
- -- Extra functions --
- ---------------------
-
- -- These functions supply slightly thicker bindings than those above.
- -- They are derived from functions in the C Run-Time Library, but may
- -- do a bit more work than just directly calling one of the Library
- -- functions.
-
- function is_regular_file (handle : int) return int;
- -- Tests if given handle is for a regular file (result 1) or for
- -- a non-regular file (pipe or device, result 0).
-
- ---------------------------------
- -- Control of Text/Binary Mode --
- ---------------------------------
-
- -- If text_translation_required is true, then the following functions may
- -- be used to dynamically switch a file from binary to text mode or vice
- -- versa. These functions have no effect if text_translation_required is
- -- false (i.e. in normal unix mode). Use fileno to get a stream handle.
-
- procedure set_binary_mode (handle : int);
- procedure set_text_mode (handle : int);
-
- ----------------------------
- -- Full Path Name support --
- ----------------------------
-
- procedure full_name (nam : chars; buffer : chars);
- -- Given a NUL terminated string representing a file name, returns in
- -- buffer a NUL terminated string representing the full path name for
- -- the file name. On systems where it is relevant the drive is also part
- -- of the full path name. It is the responsibility of the caller to
- -- pass an actual parameter for buffer that is big enough for any full
- -- path name. Use max_path_len given below as the size of buffer.
-
- max_path_len : integer;
- -- Maximum length of an allowable full path name on the system,
- -- including a terminating NUL character.
-
- private
- -- The following routines are always functions in C, and thus can be
- -- imported directly into Ada without any intermediate C needed
-
- pragma Import (C, clearerr);
- pragma Import (C, fclose);
- pragma Import (C, fdopen);
- pragma Import (C, fflush);
- pragma Import (C, fgetc);
- pragma Import (C, fgets);
- pragma Import (C, fopen);
- pragma Import (C, fputc);
- pragma Import (C, fputs);
- pragma Import (C, fread);
- pragma Import (C, freopen);
- pragma Import (C, fseek);
- pragma Import (C, ftell);
- pragma Import (C, fwrite);
- pragma Import (C, isatty);
- pragma Import (C, mktemp);
- pragma Import (C, rewind);
- pragma Import (C, rmtmp);
- pragma Import (C, setvbuf);
- pragma Import (C, tmpfile);
- pragma Import (C, ungetc);
- pragma Import (C, unlink);
-
- pragma Import (C, is_regular_file, "is_regular_file_fd");
-
- pragma Import (C, set_binary_mode);
- pragma Import (C, set_text_mode);
-
- pragma Import (C, max_path_len, "max_path_len");
- pragma Import (C, full_name, "full_name");
-
- -- The following may be implemented as macros, and so are supported
- -- via an interface function in the a-stdio.c file.
-
- pragma Import (C, feof, "feof__");
- pragma Import (C, ferror, "ferror__");
- pragma Import (C, fileno, "fileno__");
-
- -- Constants in stdio are provided via imported variables that are
- -- defined in a-stdio.c using the stdio.h header. It would be cleaner
- -- if we could import constant directly, but GNAT does not support
- -- pragma Import for constants ???
-
- c_constant_EOF : int;
-
- c_constant_IOFBF : int;
- c_constant_IOLBF : int;
- c_constant_IONBF : int;
-
- c_constant_SEEK_CUR : int;
- c_constant_SEEK_END : int;
- c_constant_SEEK_SET : int;
-
- pragma Import (C, c_constant_EOF);
- pragma Import (C, c_constant_IOFBF);
- pragma Import (C, c_constant_IOLBF);
- pragma Import (C, c_constant_IONBF);
- pragma Import (C, c_constant_SEEK_CUR);
- pragma Import (C, c_constant_SEEK_END);
- pragma Import (C, c_constant_SEEK_SET);
-
- pragma Import (C, stderr, "c_constant_stderr");
- pragma Import (C, stdin, "c_constant_stdin");
- pragma Import (C, stdout, "c_constant_stdout");
-
- EOF : constant int := c_constant_EOF;
- IOFBF : constant int := c_constant_IOFBF;
- IOLBF : constant int := c_constant_IOLBF;
- IONBF : constant int := c_constant_IONBF;
- SEEK_CUR : constant int := c_constant_SEEK_CUR;
- SEEK_END : constant int := c_constant_SEEK_END;
- SEEK_SET : constant int := c_constant_SEEK_SET;
-
- type Dummy is access Integer;
- function To_Address is new Unchecked_Conversion (Dummy, System.Address);
- -- Used to concoct the null address below
-
- NULL_Stream : constant FILEs := To_Address (Dummy'(null));
- -- Value returned (NULL in C) to indicate an fdopen/fopen/tmpfile error
-
- end Interfaces.C_Streams;
-