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) 2004-2006, 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
52 -- Used for Exception_Id
53 -- Exception_Occurrence
56 with Ada.Exceptions.Is_Null_Occurrence;
58 package body System.Soft_Links.Tasking is
60 package STPO renames System.Task_Primitives.Operations;
61 package SSL renames System.Soft_Links;
65 use type System.Tasking.Task_Id;
66 use type System.Tasking.Termination_Handler;
72 Initialized : Boolean := False;
73 -- Boolean flag that indicates whether the tasking soft links have
76 -----------------------------------------------------------------
77 -- Tasking Versions of Services Needed by Non-Tasking Programs --
78 -----------------------------------------------------------------
80 function Get_Jmpbuf_Address return Address;
81 procedure Set_Jmpbuf_Address (Addr : Address);
82 -- Get/Set Jmpbuf_Address for current task
84 function Get_Sec_Stack_Addr return Address;
85 procedure Set_Sec_Stack_Addr (Addr : Address);
86 -- Get/Set location of current task's secondary stack
88 function Get_Current_Excep return SSL.EOA;
89 -- Task-safe version of SSL.Get_Current_Excep
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 --------------------------
98 -- Soft-Link Get Bodies --
99 --------------------------
101 function Get_Current_Excep return SSL.EOA is
103 return STPO.Self.Common.Compiler_Data.Current_Excep'Access;
104 end Get_Current_Excep;
106 function Get_Jmpbuf_Address return Address is
108 return STPO.Self.Common.Compiler_Data.Jmpbuf_Address;
109 end Get_Jmpbuf_Address;
111 function Get_Sec_Stack_Addr return Address is
113 return STPO.Self.Common.Compiler_Data.Sec_Stack_Addr;
114 end Get_Sec_Stack_Addr;
116 --------------------------
117 -- Soft-Link Set Bodies --
118 --------------------------
120 procedure Set_Jmpbuf_Address (Addr : Address) is
122 STPO.Self.Common.Compiler_Data.Jmpbuf_Address := Addr;
123 end Set_Jmpbuf_Address;
125 procedure Set_Sec_Stack_Addr (Addr : Address) is
127 STPO.Self.Common.Compiler_Data.Sec_Stack_Addr := Addr;
128 end Set_Sec_Stack_Addr;
134 procedure Timed_Delay_T (Time : Duration; Mode : Integer) is
135 Self_Id : constant System.Tasking.Task_Id := STPO.Self;
138 -- In case pragma Detect_Blocking is active then Program_Error
139 -- must be raised if this potentially blocking operation
140 -- is called from a protected operation.
142 if System.Tasking.Detect_Blocking
143 and then Self_Id.Common.Protected_Action_Nesting > 0
145 raise Program_Error with "potentially blocking operation";
148 STPO.Timed_Delay (Self_Id, Time, Mode);
153 --------------------------------
154 -- Task_Termination_Handler_T --
155 --------------------------------
157 procedure Task_Termination_Handler_T (Excep : SSL.EO) is
158 Self_Id : constant System.Tasking.Task_Id := STPO.Self;
159 Cause : System.Tasking.Cause_Of_Termination;
160 EO : Ada.Exceptions.Exception_Occurrence;
163 -- We can only be here because we are terminating the environment task.
164 -- Task termination for the rest of the tasks is handled in the
167 pragma Assert (Self_Id = STPO.Environment_Task);
169 -- Normal task termination
171 if Is_Null_Occurrence (Excep) then
172 Cause := System.Tasking.Normal;
173 Ada.Exceptions.Save_Occurrence (EO, Ada.Exceptions.Null_Occurrence);
175 -- Abnormal task termination
177 elsif Exception_Identity (Excep) = Standard'Abort_Signal'Identity then
178 Cause := System.Tasking.Abnormal;
179 Ada.Exceptions.Save_Occurrence (EO, Ada.Exceptions.Null_Occurrence);
181 -- Termination because of an unhandled exception
184 Cause := System.Tasking.Unhandled_Exception;
185 Ada.Exceptions.Save_Occurrence (EO, Excep);
188 -- There is no need for explicit protection against race conditions
189 -- for this part because it can only be executed by the environment
190 -- task after all the other tasks have been finalized.
192 if Self_Id.Common.Specific_Handler /= null then
193 Self_Id.Common.Specific_Handler.all (Cause, Self_Id, EO);
194 elsif Self_Id.Common.Fall_Back_Handler /= null then
195 Self_Id.Common.Fall_Back_Handler.all (Cause, Self_Id, EO);
197 end Task_Termination_Handler_T;
199 -----------------------------
200 -- Init_Tasking_Soft_Links --
201 -----------------------------
203 procedure Init_Tasking_Soft_Links is
205 -- Set links only if not set already
207 if not Initialized then
209 -- Mark tasking soft links as initialized
213 -- The application being executed uses tasking so that the tasking
214 -- version of the following soft links need to be used.
216 SSL.Get_Jmpbuf_Address := Get_Jmpbuf_Address'Access;
217 SSL.Set_Jmpbuf_Address := Set_Jmpbuf_Address'Access;
218 SSL.Get_Sec_Stack_Addr := Get_Sec_Stack_Addr'Access;
219 SSL.Set_Sec_Stack_Addr := Set_Sec_Stack_Addr'Access;
220 SSL.Get_Current_Excep := Get_Current_Excep'Access;
221 SSL.Timed_Delay := Timed_Delay_T'Access;
222 SSL.Task_Termination_Handler := Task_Termination_Handler_T'Access;
224 -- No need to create a new Secondary Stack, since we will use the
225 -- default one created in s-secsta.adb
227 SSL.Set_Sec_Stack_Addr (SSL.Get_Sec_Stack_Addr_NT);
228 SSL.Set_Jmpbuf_Address (SSL.Get_Jmpbuf_Address_NT);
230 end Init_Tasking_Soft_Links;
232 end System.Soft_Links.Tasking;