-- --
-- B o d y --
-- --
--- --
--- Copyright (C) 1992-2001 Free Software Foundation, Inc. --
+-- Copyright (C) 1992-2010, 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- --
+-- ware Foundation; either version 3, 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. --
+-- or FITNESS FOR A PARTICULAR PURPOSE. --
+-- --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception, --
+-- version 3.1, as published by the Free Software Foundation. --
-- --
--- 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. --
+-- You should have received a copy of the GNU General Public License and --
+-- a copy of the GCC Runtime Library Exception along with this program; --
+-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
+-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
------------------------------------------------------------------------------
with System; use System;
-with System.Address_To_Access_Conversions;
+with System.Storage_Elements; use System.Storage_Elements;
+
+with Ada.Unchecked_Conversion;
package body Interfaces.C.Strings is
- package Char_Access is new Address_To_Access_Conversions (char);
+ -- Note that the type chars_ptr has a pragma No_Strict_Aliasing in the
+ -- spec, to prevent any assumptions about aliasing for values of this type,
+ -- since arbitrary addresses can be converted, and it is quite likely that
+ -- this type will in fact be used for aliasing values of other types.
+
+ function To_chars_ptr is
+ new Ada.Unchecked_Conversion (System.Parameters.C_Address, chars_ptr);
+
+ function To_Address is
+ new Ada.Unchecked_Conversion (chars_ptr, System.Parameters.C_Address);
-----------------------
-- Local Subprograms --
-- compatible, so we directly import here the malloc and free routines.
function Memory_Alloc (Size : size_t) return chars_ptr;
- pragma Import (C, Memory_Alloc, "__gnat_malloc");
+ pragma Import (C, Memory_Alloc, System.Parameters.C_Malloc_Linkname);
procedure Memory_Free (Address : chars_ptr);
pragma Import (C, Memory_Free, "__gnat_free");
function "+" (Left : chars_ptr; Right : size_t) return chars_ptr is
begin
- return Left + chars_ptr (Right);
+ return To_chars_ptr (To_Address (Left) + Storage_Offset (Right));
end "+";
----------
-- New_Char_Array --
--------------------
- function New_Char_Array (Chars : in char_array) return chars_ptr is
+ function New_Char_Array (Chars : char_array) return chars_ptr is
Index : size_t;
Pointer : chars_ptr;
begin
- -- Get index of position of null. If Index > Chars'last,
+ -- Get index of position of null. If Index > Chars'Last,
-- nul is absent and must be added explicitly.
Index := Position_Of_Nul (Into => Chars);
Pointer := Memory_Alloc ((Index - Chars'First + 1));
- -- If nul is present, transfer string up to and including it.
+ -- If nul is present, transfer string up to and including nul
if Index <= Chars'Last then
Update (Item => Pointer,
Offset => 0,
Chars => Chars,
Check => False);
- Poke (nul, into => Pointer + size_t '(Chars'Length));
+ Poke (nul, Into => Pointer + size_t'(Chars'Length));
end if;
return Pointer;
-- New_String --
----------------
- function New_String (Str : in String) return chars_ptr is
+ function New_String (Str : String) return chars_ptr is
+
+ -- It's important that this subprogram uses the heap directly to compute
+ -- the result, and doesn't copy the string on the stack, otherwise its
+ -- use is limited when used from tasks on large strings.
+
+ Result : constant chars_ptr := Memory_Alloc (Str'Length + 1);
+
+ Result_Array : char_array (1 .. Str'Length + 1);
+ for Result_Array'Address use To_Address (Result);
+ pragma Import (Ada, Result_Array);
+
+ Count : size_t;
+
begin
- return New_Char_Array (To_C (Str));
+ To_C
+ (Item => Str,
+ Target => Result_Array,
+ Count => Count,
+ Append_Nul => True);
+ return Result;
end New_String;
----------
----------
function Peek (From : chars_ptr) return char is
- use Char_Access;
begin
- return To_Pointer (Address (To_Address (From))).all;
+ return char (From.all);
end Peek;
----------
----------
procedure Poke (Value : char; Into : chars_ptr) is
- use Char_Access;
begin
- To_Pointer (Address (To_Address (Into))).all := Value;
+ Into.all := Character (Value);
end Poke;
---------------------
-- Strlen --
------------
- function Strlen (Item : in chars_ptr) return size_t is
+ function Strlen (Item : chars_ptr) return size_t is
Item_Index : size_t := 0;
begin
------------------
function To_Chars_Ptr
- (Item : in char_array_access;
- Nul_Check : in Boolean := False)
- return chars_ptr
+ (Item : char_array_access;
+ Nul_Check : Boolean := False) return chars_ptr
is
begin
if Item = null then
then
raise Terminator_Error;
else
- return To_Integer (Item (Item'First)'Address);
+ return To_chars_ptr (Item (Item'First)'Address);
end if;
end To_Chars_Ptr;
------------
procedure Update
- (Item : in chars_ptr;
- Offset : in size_t;
- Chars : in char_array;
+ (Item : chars_ptr;
+ Offset : size_t;
+ Chars : char_array;
Check : Boolean := True)
is
Index : chars_ptr := Item + Offset;
end Update;
procedure Update
- (Item : in chars_ptr;
- Offset : in size_t;
- Str : in String;
- Check : in Boolean := True)
+ (Item : chars_ptr;
+ Offset : size_t;
+ Str : String;
+ Check : Boolean := True)
is
begin
- Update (Item, Offset, To_C (Str), Check);
+ -- Note: in RM 95, the Append_Nul => False parameter is omitted. But
+ -- this has the unintended consequence of truncating the string after
+ -- an update. As discussed in Ada 2005 AI-242, this was unintended,
+ -- and should be corrected. Since this is a clear error, it seems
+ -- appropriate to apply the correction in Ada 95 mode as well.
+
+ Update (Item, Offset, To_C (Str, Append_Nul => False), Check);
end Update;
-----------
-- Value --
-----------
- function Value (Item : in chars_ptr) return char_array is
+ function Value (Item : chars_ptr) return char_array is
Result : char_array (0 .. Strlen (Item));
begin
end Value;
function Value
- (Item : in chars_ptr;
- Length : in size_t)
- return char_array
+ (Item : chars_ptr;
+ Length : size_t) return char_array
is
begin
if Item = Null_Ptr then
end;
end Value;
- function Value (Item : in chars_ptr) return String is
+ function Value (Item : chars_ptr) return String is
begin
return To_Ada (Value (Item));
end Value;
- -- As per AI-00177, this is equivalent to
- -- To_Ada (Value (Item, Length) & nul);
-
- function Value (Item : in chars_ptr; Length : in size_t) return String is
+ function Value (Item : chars_ptr; Length : size_t) return String is
Result : char_array (0 .. Length);
begin
+ -- As per AI-00177, this is equivalent to:
+
+ -- To_Ada (Value (Item, Length) & nul);
+
if Item = Null_Ptr then
raise Dereference_Error;
end if;
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