Ada 编程/库/GNAT.Exception 追溯
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-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- G N A T . E X C E P T I O N _ T R A C E S --
-- --
-- S p e c --
-- --
-- Copyright (C) 2000-2019, AdaCore --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
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-- This package provides an interface allowing to control *automatic* output
-- to standard error upon exception occurrences (as opposed to explicit
-- generation of traceback information using System.Traceback).
-- See file s-exctra.ads for full documentation of the interface
with System.Exception_Traces;
package GNAT.Exception_Traces renames System.Exception_Traces;
s-exctra.ads
-- ...
-- This package provides an interface allowing to control *automatic* output
-- to standard error upon exception occurrences (as opposed to explicit
-- generation of traceback information using System.Traceback).
-- This output includes the basic information associated with the exception
-- (name, message) as well as a backtrace of the call chain at the point
-- where the exception occurred. This backtrace is only output if the call
-- chain information is available, depending if the binder switch dedicated
-- to that purpose has been used or not.
-- The default backtrace is in the form of absolute code locations which may
-- be converted to corresponding source locations using the addr2line utility
-- or from within GDB. Please refer to System.Traceback for information about
-- what is necessary to be able to exploit this possibility.
-- The backtrace output can also be customized by way of a "decorator" which
-- may return any string output in association with a provided call chain.
-- The decorator replaces the default backtrace mentioned above.
-- On systems that use DWARF debugging output, then if the "-g" compiler
-- switch and the "-Es" binder switch are used, the decorator is automatically
-- set to Symbolic_Traceback.
with System.Traceback_Entries;
package System.Exception_Traces is
-- The following defines the exact situations in which raises will
-- cause automatic output of trace information.
type Trace_Kind is
(Every_Raise,
-- Denotes the initial raise event for any exception occurrence, either
-- explicit or due to a specific language rule, within the context of a
-- task or not.
Unhandled_Raise,
-- Denotes the raise events corresponding to exceptions for which there
-- is no user defined handler. This includes unhandled exceptions in
-- task bodies.
Unhandled_Raise_In_Main
-- Same as Unhandled_Raise, except exceptions in task bodies are not
-- included.
);
-- The following procedures can be used to activate and deactivate
-- traces identified by the above trace kind values.
procedure Trace_On (Kind : Trace_Kind);
-- Activate the traces denoted by Kind
procedure Trace_Off;
-- Stop the tracing requested by the last call to Trace_On.
-- Has no effect if no such call has ever occurred.
-- The following provide the backtrace decorating facilities
type Traceback_Decorator is access
function (Traceback : Traceback_Entries.Tracebacks_Array) return String;
-- A backtrace decorator is a function which returns the string to be
-- output for a call chain provided by way of a tracebacks array.
procedure Set_Trace_Decorator (Decorator : Traceback_Decorator);
-- Set the decorator to be used for future automatic outputs. Restore the
-- default behavior if the provided access value is null.
--
-- Note: System.Traceback.Symbolic.Symbolic_Traceback may be used as the
-- Decorator, to get a symbolic traceback. This will cause a significant
-- cpu and memory overhead on some platforms.
--
-- Note: The Decorator is called when constructing the
-- Exception_Information; that needs to be taken into account
-- if the Decorator has any side effects.
end System.Exception_Traces;