1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- S Y S T E M . S O F T _ L I N K S . T A S K I N G --
9 -- Copyright (C) 2004-2007, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 pragma Style_Checks (All_Checks);
35 -- Turn off subprogram alpha ordering check, since we group soft link
36 -- bodies and dummy soft link bodies together separately in this unit.
39 -- Turn polling off for this package. We don't need polling during any
40 -- of the routines in this package, and more to the point, if we try
41 -- to poll it can cause infinite loops.
43 with System.Task_Primitives.Operations;
49 -- Cause_Of_Termination
51 with System.Stack_Checking;
52 -- Used for Stack_Access
55 -- Used for Exception_Id
56 -- Exception_Occurrence
59 with Ada.Exceptions.Is_Null_Occurrence;
61 package body System.Soft_Links.Tasking is
63 package STPO renames System.Task_Primitives.Operations;
64 package SSL renames System.Soft_Links;
68 use type System.Tasking.Task_Id;
69 use type System.Tasking.Termination_Handler;
75 Initialized : Boolean := False;
76 -- Boolean flag that indicates whether the tasking soft links have
79 -----------------------------------------------------------------
80 -- Tasking Versions of Services Needed by Non-Tasking Programs --
81 -----------------------------------------------------------------
83 function Get_Jmpbuf_Address return Address;
84 procedure Set_Jmpbuf_Address (Addr : Address);
85 -- Get/Set Jmpbuf_Address for current task
87 function Get_Sec_Stack_Addr return Address;
88 procedure Set_Sec_Stack_Addr (Addr : Address);
89 -- Get/Set location of current task's secondary stack
91 procedure Timed_Delay_T (Time : Duration; Mode : Integer);
92 -- Task-safe version of SSL.Timed_Delay
94 procedure Task_Termination_Handler_T (Excep : SSL.EO);
95 -- Task-safe version of the task termination procedure
97 function Get_Stack_Info return Stack_Checking.Stack_Access;
98 -- Get access to the current task's Stack_Info
100 --------------------------
101 -- Soft-Link Get Bodies --
102 --------------------------
104 function Get_Jmpbuf_Address return Address is
106 return STPO.Self.Common.Compiler_Data.Jmpbuf_Address;
107 end Get_Jmpbuf_Address;
109 function Get_Sec_Stack_Addr return Address is
111 return STPO.Self.Common.Compiler_Data.Sec_Stack_Addr;
112 end Get_Sec_Stack_Addr;
114 function Get_Stack_Info return Stack_Checking.Stack_Access is
116 return STPO.Self.Common.Compiler_Data.Pri_Stack_Info'Access;
119 --------------------------
120 -- Soft-Link Set Bodies --
121 --------------------------
123 procedure Set_Jmpbuf_Address (Addr : Address) is
125 STPO.Self.Common.Compiler_Data.Jmpbuf_Address := Addr;
126 end Set_Jmpbuf_Address;
128 procedure Set_Sec_Stack_Addr (Addr : Address) is
130 STPO.Self.Common.Compiler_Data.Sec_Stack_Addr := Addr;
131 end Set_Sec_Stack_Addr;
137 procedure Timed_Delay_T (Time : Duration; Mode : Integer) is
138 Self_Id : constant System.Tasking.Task_Id := STPO.Self;
141 -- In case pragma Detect_Blocking is active then Program_Error
142 -- must be raised if this potentially blocking operation
143 -- is called from a protected operation.
145 if System.Tasking.Detect_Blocking
146 and then Self_Id.Common.Protected_Action_Nesting > 0
148 raise Program_Error with "potentially blocking operation";
151 STPO.Timed_Delay (Self_Id, Time, Mode);
156 --------------------------------
157 -- Task_Termination_Handler_T --
158 --------------------------------
160 procedure Task_Termination_Handler_T (Excep : SSL.EO) is
161 Self_Id : constant System.Tasking.Task_Id := STPO.Self;
162 Cause : System.Tasking.Cause_Of_Termination;
163 EO : Ada.Exceptions.Exception_Occurrence;
166 -- We can only be here because we are terminating the environment task.
167 -- Task termination for the rest of the tasks is handled in the
170 pragma Assert (Self_Id = STPO.Environment_Task);
172 -- Normal task termination
174 if Is_Null_Occurrence (Excep) then
175 Cause := System.Tasking.Normal;
176 Ada.Exceptions.Save_Occurrence (EO, Ada.Exceptions.Null_Occurrence);
178 -- Abnormal task termination
180 elsif Exception_Identity (Excep) = Standard'Abort_Signal'Identity then
181 Cause := System.Tasking.Abnormal;
182 Ada.Exceptions.Save_Occurrence (EO, Ada.Exceptions.Null_Occurrence);
184 -- Termination because of an unhandled exception
187 Cause := System.Tasking.Unhandled_Exception;
188 Ada.Exceptions.Save_Occurrence (EO, Excep);
191 -- There is no need for explicit protection against race conditions
192 -- for this part because it can only be executed by the environment
193 -- task after all the other tasks have been finalized.
195 if Self_Id.Common.Specific_Handler /= null then
196 Self_Id.Common.Specific_Handler.all (Cause, Self_Id, EO);
197 elsif Self_Id.Common.Fall_Back_Handler /= null then
198 Self_Id.Common.Fall_Back_Handler.all (Cause, Self_Id, EO);
200 end Task_Termination_Handler_T;
202 -----------------------------
203 -- Init_Tasking_Soft_Links --
204 -----------------------------
206 procedure Init_Tasking_Soft_Links is
208 -- Set links only if not set already
210 if not Initialized then
212 -- Mark tasking soft links as initialized
216 -- The application being executed uses tasking so that the tasking
217 -- version of the following soft links need to be used.
219 SSL.Get_Jmpbuf_Address := Get_Jmpbuf_Address'Access;
220 SSL.Set_Jmpbuf_Address := Set_Jmpbuf_Address'Access;
221 SSL.Get_Sec_Stack_Addr := Get_Sec_Stack_Addr'Access;
222 SSL.Get_Stack_Info := Get_Stack_Info'Access;
223 SSL.Set_Sec_Stack_Addr := Set_Sec_Stack_Addr'Access;
224 SSL.Timed_Delay := Timed_Delay_T'Access;
225 SSL.Task_Termination_Handler := Task_Termination_Handler_T'Access;
227 -- No need to create a new Secondary Stack, since we will use the
228 -- default one created in s-secsta.adb
230 SSL.Set_Sec_Stack_Addr (SSL.Get_Sec_Stack_Addr_NT);
231 SSL.Set_Jmpbuf_Address (SSL.Get_Jmpbuf_Address_NT);
233 end Init_Tasking_Soft_Links;
235 end System.Soft_Links.Tasking;