New Language: Ada

From-SVN: r45957

1 files changed, 162 insertions, 0 deletions

diff --git a/gcc/ada/s-gloloc.adb b/gcc/ada/s-gloloc.adb
new file mode 100644
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+++ b/gcc/ada/s-gloloc.adb
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+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                  S Y S T E M . G L O B A L _ L O C K S                   --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--                            $Revision: 1.6 $                               --
+--                                                                          --
+--           Copyright (C) 1999-2001 Ada Core Technologies, 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).   --
+--                                                                          --
+------------------------------------------------------------------------------
+
+with GNAT.Task_Lock;
+
+package body System.Global_Locks is
+
+   type String_Access is access String;
+
+   package TSL renames GNAT.Task_Lock;
+
+   Dir_Separator : Character;
+   pragma Import (C, Dir_Separator, "__gnat_dir_separator");
+
+   type Lock_File_Entry is
+      record
+         Dir  : String_Access;
+         File : String_Access;
+      end record;
+
+   Last_Lock  : Lock_Type := Null_Lock;
+   Lock_Table : array (Lock_Type range 1 .. 15) of Lock_File_Entry;
+
+   procedure Lock_File
+     (Dir     : String;
+      File    : String;
+      Wait    : Duration := 0.1;
+      Retries : Natural  := Natural'Last);
+   --  Create a lock file File in directory Dir. If the file  cannot be
+   --  locked because someone already owns the lock, this procedure
+   --  waits Wait seconds and retries at most Retries times. If the file
+   --  still cannot be locked, Lock_Error is raised. The default is to try
+   --  every second, almost forever (Natural'Last times).
+
+   ------------------
+   -- Acquire_Lock --
+   ------------------
+
+   procedure Acquire_Lock
+     (Lock : in out Lock_Type)
+   is
+   begin
+      Lock_File
+        (Lock_Table (Lock).Dir.all,
+         Lock_Table (Lock).File.all);
+   end Acquire_Lock;
+
+   -----------------
+   -- Create_Lock --
+   -----------------
+
+   procedure Create_Lock
+     (Lock : out Lock_Type;
+      Name : in String)
+   is
+      L : Lock_Type;
+
+   begin
+      TSL.Lock;
+      Last_Lock := Last_Lock + 1;
+      L := Last_Lock;
+      TSL.Unlock;
+
+      if L > Lock_Table'Last then
+         raise Lock_Error;
+      end if;
+
+      for J in reverse Name'Range loop
+         if Name (J) = Dir_Separator then
+            Lock_Table (L).Dir
+              := new String'(Name (Name'First .. J - 1));
+            Lock_Table (L).File
+              := new String'(Name (J + 1 .. Name'Last));
+            exit;
+         end if;
+      end loop;
+
+      if Lock_Table (L).Dir = null then
+         Lock_Table (L).Dir  := new String'(".");
+         Lock_Table (L).File := new String'(Name);
+      end if;
+
+      Lock := L;
+   end Create_Lock;
+
+   ---------------
+   -- Lock_File --
+   ---------------
+
+   procedure Lock_File
+     (Dir     : String;
+      File    : String;
+      Wait    : Duration := 0.1;
+      Retries : Natural  := Natural'Last)
+   is
+      C_Dir  : aliased String := Dir & ASCII.NUL;
+      C_File : aliased String := File & ASCII.NUL;
+
+      function Try_Lock (Dir, File : System.Address) return Integer;
+      pragma Import (C, Try_Lock, "__gnat_try_lock");
+
+   begin
+      for I in 0 .. Retries loop
+         if Try_Lock (C_Dir'Address, C_File'Address) = 1 then
+            return;
+         end if;
+         exit when I = Retries;
+         delay Wait;
+      end loop;
+      raise Lock_Error;
+   end Lock_File;
+
+   ------------------
+   -- Release_Lock --
+   ------------------
+
+   procedure Release_Lock
+     (Lock : in out Lock_Type)
+   is
+      S : aliased String :=
+        Lock_Table (Lock).Dir.all & Dir_Separator &
+        Lock_Table (Lock).File.all & ASCII.NUL;
+
+      procedure unlink (A : System.Address);
+      pragma Import (C, unlink, "unlink");
+
+   begin
+      unlink (S'Address);
+   end Release_Lock;
+
+end System.Global_Locks;