File : s-traceb.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S Y S T E M . T R A C E B A C K --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1999-2015, 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 -- --
19 -- --
20 -- --
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
32 -- This package provides a method for generating a traceback of the current
33 -- execution location. The traceback shows the locations of calls in the call
34 -- chain, up to either the top or a designated number of levels.
35
36 pragma Compiler_Unit_Warning;
37
38 pragma Polling (Off);
39 -- We must turn polling off for this unit, because otherwise we get
40 -- elaboration circularities with System.Exception_Tables.
41
42 with System.Traceback_Entries;
43
44 package System.Traceback is
45
46 ----------------
47 -- Call_Chain --
48 ----------------
49
50 procedure Call_Chain
51 (Traceback : in out System.Traceback_Entries.Tracebacks_Array;
52 Max_Len : Natural;
53 Len : out Natural;
54 Exclude_Min : System.Address := System.Null_Address;
55 Exclude_Max : System.Address := System.Null_Address;
56 Skip_Frames : Natural := 1);
57 -- Store up to Max_Len code locations in Traceback, corresponding to the
58 -- current call chain.
59 --
60 -- Traceback is an array of addresses where the result will be stored.
61 --
62 -- Max_Len is the length of the Traceback array. If the call chain is
63 -- longer than this, then additional entries are discarded, and the
64 -- traceback is missing some of the highest level entries.
65 --
66 -- Len is the number of addresses returned in the Traceback array
67 --
68 -- Exclude_Min/Exclude_Max, if non null, provide a range of addresses
69 -- to ignore from the computation of the traceback.
70 --
71 -- Skip_Frames says how many of the most recent calls should at least
72 -- be excluded from the result, regardless of the exclusion bounds and
73 -- starting with this procedure itself: 1 means exclude the frame for
74 -- this procedure, 2 means 1 + exclude the frame for this procedure's
75 -- caller, ...
76 --
77 -- On return, the Traceback array is filled in, and Len indicates the
78 -- number of stored entries. The first entry is the most recent call,
79 -- and the last entry is the highest level call.
80
81 function C_Call_Chain
82 (Traceback : System.Address;
83 Max_Len : Natural) return Natural;
84 pragma Export (C, C_Call_Chain, "system__traceback__c_call_chain");
85 -- Version that can be used directly from C
86
87 end System.Traceback;