1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                     ADA.EXCEPTIONS.STREAM_ATTRIBUTES                     --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2015, 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------------------------------------------------------------------------------
31
32pragma Warnings (Off);
33--  Allow withing of non-Preelaborated units in Ada 2005 mode where this
34--  package will be categorized as Preelaborate. See AI-362 for details.
35--  It is safe in the context of the run-time to violate the rules.
36
37with System.Exception_Table;  use System.Exception_Table;
38with System.Storage_Elements; use System.Storage_Elements;
39
40pragma Warnings (On);
41
42separate (Ada.Exceptions)
43package body Stream_Attributes is
44
45   -------------------
46   -- EId_To_String --
47   -------------------
48
49   function EId_To_String (X : Exception_Id) return String is
50   begin
51      if X = Null_Id then
52         return "";
53      else
54         return Exception_Name (X);
55      end if;
56   end EId_To_String;
57
58   ------------------
59   -- EO_To_String --
60   ------------------
61
62   --  We use the null string to represent the null occurrence, otherwise we
63   --  output the Untailored_Exception_Information string for the occurrence.
64
65   function EO_To_String (X : Exception_Occurrence) return String is
66   begin
67      if X.Id = Null_Id then
68         return "";
69      else
70         return Exception_Data.Untailored_Exception_Information (X);
71      end if;
72   end EO_To_String;
73
74   -------------------
75   -- String_To_EId --
76   -------------------
77
78   function String_To_EId (S : String) return Exception_Id is
79   begin
80      if S = "" then
81         return Null_Id;
82      else
83         return Exception_Id (Internal_Exception (S));
84      end if;
85   end String_To_EId;
86
87   ------------------
88   -- String_To_EO --
89   ------------------
90
91   function String_To_EO (S : String) return Exception_Occurrence is
92      From : Natural;
93      To   : Integer;
94
95      X    : aliased Exception_Occurrence;
96      --  This is the exception occurrence we will create
97
98      procedure Bad_EO;
99      pragma No_Return (Bad_EO);
100      --  Signal bad exception occurrence string
101
102      procedure Next_String;
103      --  On entry, To points to last character of previous line of the
104      --  message, terminated by LF. On return, From .. To are set to
105      --  specify the next string, or From > To if there are no more lines.
106
107      procedure Bad_EO is
108      begin
109         Raise_Exception
110           (Program_Error'Identity,
111            "bad exception occurrence in stream input");
112
113         --  The following junk raise of Program_Error is required because
114         --  this is a No_Return procedure, and unfortunately Raise_Exception
115         --  can return (this particular call can't, but the back end is not
116         --  clever enough to know that).
117
118         raise Program_Error;
119      end Bad_EO;
120
121      procedure Next_String is
122      begin
123         From := To + 2;
124
125         if From < S'Last then
126            To := From + 1;
127
128            while To < S'Last - 1 loop
129               if To >= S'Last then
130                  Bad_EO;
131               elsif S (To + 1) = ASCII.LF then
132                  exit;
133               else
134                  To := To + 1;
135               end if;
136            end loop;
137         end if;
138      end Next_String;
139
140   --  Start of processing for String_To_EO
141
142   begin
143      if S = "" then
144         return Null_Occurrence;
145      end if;
146
147      To := S'First - 2;
148      Next_String;
149
150      if S (From .. From + 6) /= "raised " then
151         Bad_EO;
152      end if;
153
154      declare
155         Name_Start : constant Positive := From + 7;
156      begin
157         From := Name_Start + 1;
158
159         while From < To and then S (From) /= ' ' loop
160            From := From + 1;
161         end loop;
162
163         X.Id :=
164           Exception_Id (Internal_Exception (S (Name_Start .. From - 1)));
165      end;
166
167      if From <= To then
168         if S (From .. From + 2) /= " : " then
169            Bad_EO;
170         end if;
171
172         X.Msg_Length := To - From - 2;
173         X.Msg (1 .. X.Msg_Length) := S (From + 3 .. To);
174
175      else
176         X.Msg_Length := 0;
177      end if;
178
179      Next_String;
180      X.Pid := 0;
181
182      if From <= To and then S (From) = 'P' then
183         if S (From .. From + 3) /= "PID:" then
184            Bad_EO;
185         end if;
186
187         From := From + 5; -- skip past PID: space
188
189         while From <= To loop
190            X.Pid := X.Pid * 10 +
191                       (Character'Pos (S (From)) - Character'Pos ('0'));
192            From := From + 1;
193         end loop;
194
195         Next_String;
196      end if;
197
198      X.Num_Tracebacks := 0;
199
200      if From <= To then
201         if S (From .. To) /= "Call stack traceback locations:" then
202            Bad_EO;
203         end if;
204
205         Next_String;
206         loop
207            exit when From > To;
208
209            declare
210               Ch : Character;
211               C  : Integer_Address;
212               N  : Integer_Address;
213
214            begin
215               if S (From) /= '0'
216                 or else S (From + 1) /= 'x'
217               then
218                  Bad_EO;
219               else
220                  From := From + 2;
221               end if;
222
223               C := 0;
224               while From <= To loop
225                  Ch := S (From);
226
227                  if Ch in '0' .. '9' then
228                     N :=
229                       Character'Pos (S (From)) - Character'Pos ('0');
230
231                  elsif Ch in 'a' .. 'f' then
232                     N :=
233                       Character'Pos (S (From)) - Character'Pos ('a') + 10;
234
235                  elsif Ch = ' ' then
236                     From := From + 1;
237                     exit;
238
239                  else
240                     Bad_EO;
241                  end if;
242
243                  C := C * 16 + N;
244
245                  From := From + 1;
246               end loop;
247
248               if X.Num_Tracebacks = Max_Tracebacks then
249                  Bad_EO;
250               end if;
251
252               X.Num_Tracebacks := X.Num_Tracebacks + 1;
253               X.Tracebacks (X.Num_Tracebacks) :=
254                 TBE.TB_Entry_For (To_Address (C));
255            end;
256         end loop;
257      end if;
258
259      --  If an exception was converted to a string, it must have
260      --  already been raised, so flag it accordingly and we are done.
261
262      X.Exception_Raised := True;
263      return X;
264   end String_To_EO;
265
266end Stream_Attributes;
267