LWG 3035. std::allocator's constructors should be constexpr
[official-gcc.git] / gcc / ada / libgnarl / s-solita.adb
blob56fcacead749b22ea6105d13afcb3522a2659d81
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S Y S T E M . S O F T _ L I N K S . T A S K I N G --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 2004-2018, Free Software Foundation, Inc. --
10 -- --
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 3, 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. --
17 -- --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
32 pragma Style_Checks (All_Checks);
33 -- Turn off subprogram alpha ordering check, since we group soft link bodies
34 -- and dummy soft link bodies together separately in this unit.
36 pragma Polling (Off);
37 -- Turn polling off for this package. We don't need polling during any of the
38 -- routines in this package, and more to the point, if we try to poll it can
39 -- cause infinite loops.
41 with Ada.Exceptions;
42 with Ada.Exceptions.Is_Null_Occurrence;
44 with System.Task_Primitives.Operations;
45 with System.Tasking;
46 with System.Stack_Checking;
47 with System.Secondary_Stack;
49 package body System.Soft_Links.Tasking is
51 package STPO renames System.Task_Primitives.Operations;
52 package SSL renames System.Soft_Links;
54 use Ada.Exceptions;
56 use type System.Secondary_Stack.SS_Stack_Ptr;
58 use type System.Tasking.Task_Id;
59 use type System.Tasking.Termination_Handler;
61 ----------------
62 -- Local Data --
63 ----------------
65 Initialized : Boolean := False;
66 -- Boolean flag that indicates whether the tasking soft links have
67 -- already been set.
69 -----------------------------------------------------------------
70 -- Tasking Versions of Services Needed by Non-Tasking Programs --
71 -----------------------------------------------------------------
73 function Get_Jmpbuf_Address return Address;
74 procedure Set_Jmpbuf_Address (Addr : Address);
75 -- Get/Set Jmpbuf_Address for current task
77 function Get_Sec_Stack return SST.SS_Stack_Ptr;
78 procedure Set_Sec_Stack (Stack : SST.SS_Stack_Ptr);
79 -- Get/Set location of current task's secondary stack
81 procedure Timed_Delay_T (Time : Duration; Mode : Integer);
82 -- Task-safe version of SSL.Timed_Delay
84 procedure Task_Termination_Handler_T (Excep : SSL.EO);
85 -- Task-safe version of the task termination procedure
87 function Get_Stack_Info return Stack_Checking.Stack_Access;
88 -- Get access to the current task's Stack_Info
90 --------------------------
91 -- Soft-Link Get Bodies --
92 --------------------------
94 function Get_Jmpbuf_Address return Address is
95 begin
96 return STPO.Self.Common.Compiler_Data.Jmpbuf_Address;
97 end Get_Jmpbuf_Address;
99 function Get_Sec_Stack return SST.SS_Stack_Ptr is
100 begin
101 return Result : constant SST.SS_Stack_Ptr :=
102 STPO.Self.Common.Compiler_Data.Sec_Stack_Ptr
104 pragma Assert (Result /= null);
105 end return;
106 end Get_Sec_Stack;
108 function Get_Stack_Info return Stack_Checking.Stack_Access is
109 begin
110 return STPO.Self.Common.Compiler_Data.Pri_Stack_Info'Access;
111 end Get_Stack_Info;
113 --------------------------
114 -- Soft-Link Set Bodies --
115 --------------------------
117 procedure Set_Jmpbuf_Address (Addr : Address) is
118 begin
119 STPO.Self.Common.Compiler_Data.Jmpbuf_Address := Addr;
120 end Set_Jmpbuf_Address;
122 procedure Set_Sec_Stack (Stack : SST.SS_Stack_Ptr) is
123 begin
124 STPO.Self.Common.Compiler_Data.Sec_Stack_Ptr := Stack;
125 end Set_Sec_Stack;
127 -------------------
128 -- Timed_Delay_T --
129 -------------------
131 procedure Timed_Delay_T (Time : Duration; Mode : Integer) is
132 Self_Id : constant System.Tasking.Task_Id := STPO.Self;
134 begin
135 -- In case pragma Detect_Blocking is active then Program_Error
136 -- must be raised if this potentially blocking operation
137 -- is called from a protected operation.
139 if System.Tasking.Detect_Blocking
140 and then Self_Id.Common.Protected_Action_Nesting > 0
141 then
142 raise Program_Error with "potentially blocking operation";
143 else
144 Abort_Defer.all;
145 STPO.Timed_Delay (Self_Id, Time, Mode);
146 Abort_Undefer.all;
147 end if;
148 end Timed_Delay_T;
150 --------------------------------
151 -- Task_Termination_Handler_T --
152 --------------------------------
154 procedure Task_Termination_Handler_T (Excep : SSL.EO) is
155 Self_Id : constant System.Tasking.Task_Id := STPO.Self;
156 Cause : System.Tasking.Cause_Of_Termination;
157 EO : Ada.Exceptions.Exception_Occurrence;
159 begin
160 -- We can only be here because we are terminating the environment task.
161 -- Task termination for all other tasks is handled in the Task_Wrapper.
163 -- We do not want to enable this check and e.g. call System.OS_Lib.Abort
164 -- here because some restricted run-times may not have System.OS_Lib
165 -- and calling abort may do more harm than good to the main application.
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
183 else
184 Cause := System.Tasking.Unhandled_Exception;
185 Ada.Exceptions.Save_Occurrence (EO, Excep);
186 end if;
188 -- There is no need for explicit protection against race conditions for
189 -- this part because it can only be executed by the environment task
190 -- after all the other tasks have been finalized. Note that there is no
191 -- fall-back handler which could apply to this environment task because
192 -- it has no parents, and, as specified in ARM C.7.3 par. 9/2, "the
193 -- fall-back handler applies only to the dependent tasks of the task".
195 if Self_Id.Common.Specific_Handler /= null then
196 Self_Id.Common.Specific_Handler.all (Cause, Self_Id, EO);
197 end if;
198 end Task_Termination_Handler_T;
200 -----------------------------
201 -- Init_Tasking_Soft_Links --
202 -----------------------------
204 procedure Init_Tasking_Soft_Links is
205 begin
206 -- Set links only if not set already
208 if not Initialized then
210 -- Mark tasking soft links as initialized
212 Initialized := True;
214 -- The application being executed uses tasking so that the tasking
215 -- version of the following soft links need to be used.
217 SSL.Get_Jmpbuf_Address := Get_Jmpbuf_Address'Access;
218 SSL.Set_Jmpbuf_Address := Set_Jmpbuf_Address'Access;
219 SSL.Get_Sec_Stack := Get_Sec_Stack'Access;
220 SSL.Get_Stack_Info := Get_Stack_Info'Access;
221 SSL.Set_Sec_Stack := Set_Sec_Stack'Access;
222 SSL.Timed_Delay := Timed_Delay_T'Access;
223 SSL.Task_Termination_Handler := Task_Termination_Handler_T'Access;
225 -- No need to create a new secondary stack, since we will use the
226 -- default one created in s-secsta.adb.
228 SSL.Set_Sec_Stack (SSL.Get_Sec_Stack_NT);
229 SSL.Set_Jmpbuf_Address (SSL.Get_Jmpbuf_Address_NT);
230 end if;
232 pragma Assert (Get_Sec_Stack /= null);
233 end Init_Tasking_Soft_Links;
235 end System.Soft_Links.Tasking;