| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- ADA.EXCEPTIONS.EXCEPTION_DATA -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2003 Free Software Foundation, Inc. -- |
| -- -- |
| -- 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 2, 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. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- |
| -- MA 02111-1307, USA. -- |
| -- -- |
| -- As a special exception, if other files instantiate generics from this -- |
| -- unit, or you link this unit with other files to produce an executable, -- |
| -- this unit does not by itself cause the resulting executable to be -- |
| -- covered by the GNU General Public License. This exception does not -- |
| -- however invalidate any other reasons why the executable file might be -- |
| -- covered by the GNU Public License. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with System.Storage_Elements; use System.Storage_Elements; |
| |
| separate (Ada.Exceptions) |
| package body Exception_Data is |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| function Address_Image (A : System.Address) return String; |
| -- Returns at string of the form 0xhhhhhhhhh for an address, with |
| -- leading zeros suppressed. Hex characters a-f are in lower case. |
| |
| procedure Append_Info_Nat |
| (N : Natural; |
| Info : in out String; |
| Ptr : in out Natural); |
| -- Append the image of N at the end of the provided information string |
| |
| procedure Append_Info_NL |
| (Info : in out String; |
| Ptr : in out Natural); |
| -- Append a LF at the end of the provided information string |
| |
| procedure Append_Info_String |
| (S : String; |
| Info : in out String; |
| Ptr : in out Natural); |
| -- Append a string at the end of the provided information string |
| |
| -- To build Exception_Information and Tailored_Exception_Information, |
| -- we then use three intermediate functions : |
| |
| function Basic_Exception_Information |
| (X : Exception_Occurrence) return String; |
| -- Returns the basic exception information string associated with a |
| -- given exception occurrence. This is the common part shared by both |
| -- Exception_Information and Tailored_Exception_Infomation. |
| |
| function Basic_Exception_Traceback |
| (X : Exception_Occurrence) return String; |
| -- Returns an image of the complete call chain associated with an |
| -- exception occurence in its most basic form, that is as a raw sequence |
| -- of hexadecimal binary addresses. |
| |
| function Tailored_Exception_Traceback |
| (X : Exception_Occurrence) return String; |
| -- Returns an image of the complete call chain associated with an |
| -- exception occurrence, either in its basic form if no decorator is |
| -- in place, or as formatted by the decorator otherwise. |
| |
| -- The overall organization of the exception information related code |
| -- is summarized below : |
| -- |
| -- Exception_Information |
| -- | |
| -- +-------+--------+ |
| -- | | |
| -- Basic_Exc_Info & Basic_Exc_Tback |
| -- |
| -- |
| -- Tailored_Exception_Information |
| -- | |
| -- +----------+----------+ |
| -- | | |
| -- Basic_Exc_Info & Tailored_Exc_Tback |
| -- | |
| -- +-----------+------------+ |
| -- | | |
| -- Basic_Exc_Tback Or Tback_Decorator |
| -- if no decorator set otherwise |
| |
| ------------------- |
| -- Address_Image -- |
| ------------------- |
| |
| function Address_Image (A : Address) return String is |
| S : String (1 .. 18); |
| P : Natural; |
| N : Integer_Address; |
| |
| H : constant array (Integer range 0 .. 15) of Character := |
| "0123456789abcdef"; |
| begin |
| P := S'Last; |
| N := To_Integer (A); |
| loop |
| S (P) := H (Integer (N mod 16)); |
| P := P - 1; |
| N := N / 16; |
| exit when N = 0; |
| end loop; |
| |
| S (P - 1) := '0'; |
| S (P) := 'x'; |
| return S (P - 1 .. S'Last); |
| end Address_Image; |
| |
| --------------------- |
| -- Append_Info_Nat -- |
| --------------------- |
| |
| procedure Append_Info_Nat |
| (N : Natural; |
| Info : in out String; |
| Ptr : in out Natural) |
| is |
| begin |
| if N > 9 then |
| Append_Info_Nat (N / 10, Info, Ptr); |
| end if; |
| |
| Ptr := Ptr + 1; |
| Info (Ptr) := Character'Val (Character'Pos ('0') + N mod 10); |
| end Append_Info_Nat; |
| |
| -------------------- |
| -- Append_Info_NL -- |
| -------------------- |
| |
| procedure Append_Info_NL |
| (Info : in out String; |
| Ptr : in out Natural) |
| is |
| begin |
| Ptr := Ptr + 1; |
| Info (Ptr) := ASCII.LF; |
| end Append_Info_NL; |
| |
| ------------------------ |
| -- Append_Info_String -- |
| ------------------------ |
| |
| procedure Append_Info_String |
| (S : String; |
| Info : in out String; |
| Ptr : in out Natural) |
| is |
| Last : constant Natural := Integer'Min (Ptr + S'Length, Info'Last); |
| |
| begin |
| Info (Ptr + 1 .. Last) := S; |
| Ptr := Last; |
| end Append_Info_String; |
| |
| --------------------------------- |
| -- Basic_Exception_Information -- |
| --------------------------------- |
| |
| function Basic_Exception_Information |
| (X : Exception_Occurrence) return String |
| is |
| Name : constant String := Exception_Name (X); |
| Msg : constant String := Exception_Message (X); |
| -- Exception name and message that are going to be included in the |
| -- information to return, if not empty. |
| |
| Name_Len : constant Natural := Name'Length; |
| Msg_Len : constant Natural := Msg'Length; |
| -- Length of these strings, useful to compute the size of the string |
| -- we have to allocate for the complete result as well as in the body |
| -- of this procedure. |
| |
| Info_Maxlen : constant Natural := 50 + Name_Len + Msg_Len; |
| -- Maximum length of the information string we will build, with : |
| -- |
| -- 50 = 16 + 2 for the text associated with the name |
| -- + 9 + 2 for the text associated with the message |
| -- + 5 + 2 for the text associated with the pid |
| -- + 14 for the text image of the pid itself and a margin. |
| -- |
| -- This is indeed a maximum since some data may not appear at all if |
| -- not relevant. For example, nothing related to the exception message |
| -- will be there if this message is empty. |
| -- |
| -- WARNING : Do not forget to update these numbers if anything |
| -- involved in the computation changes. |
| |
| Info : String (1 .. Info_Maxlen); |
| -- Information string we are going to build, containing the common |
| -- part shared by Exc_Info and Tailored_Exc_Info. |
| |
| Ptr : Natural := 0; |
| |
| begin |
| -- Output exception name and message except for _ABORT_SIGNAL, where |
| -- these two lines are omitted (see discussion above). |
| |
| if Name (1) /= '_' then |
| Append_Info_String ("Exception name: ", Info, Ptr); |
| Append_Info_String (Name, Info, Ptr); |
| Append_Info_NL (Info, Ptr); |
| |
| if Msg_Len /= 0 then |
| Append_Info_String ("Message: ", Info, Ptr); |
| Append_Info_String (Msg, Info, Ptr); |
| Append_Info_NL (Info, Ptr); |
| end if; |
| end if; |
| |
| -- Output PID line if non-zero |
| |
| if X.Pid /= 0 then |
| Append_Info_String ("PID: ", Info, Ptr); |
| Append_Info_Nat (X.Pid, Info, Ptr); |
| Append_Info_NL (Info, Ptr); |
| end if; |
| |
| return Info (1 .. Ptr); |
| end Basic_Exception_Information; |
| |
| ------------------------------- |
| -- Basic_Exception_Traceback -- |
| ------------------------------- |
| |
| function Basic_Exception_Traceback |
| (X : Exception_Occurrence) return String |
| is |
| Info_Maxlen : constant Natural := 35 + X.Num_Tracebacks * 19; |
| -- Maximum length of the information string we are building, with : |
| -- 33 = 31 + 4 for the text before and after the traceback, and |
| -- 19 = 2 + 16 + 1 for each address ("0x" + HHHH + " ") |
| -- |
| -- WARNING : Do not forget to update these numbers if anything |
| -- involved in the computation changes. |
| |
| Info : String (1 .. Info_Maxlen); |
| -- Information string we are going to build, containing an image |
| -- of the call chain associated with the exception occurrence in its |
| -- most basic form, that is as a sequence of binary addresses. |
| |
| Ptr : Natural := 0; |
| |
| begin |
| if X.Num_Tracebacks > 0 then |
| Append_Info_String ("Call stack traceback locations:", Info, Ptr); |
| Append_Info_NL (Info, Ptr); |
| |
| for J in 1 .. X.Num_Tracebacks loop |
| Append_Info_String |
| (Address_Image (TBE.PC_For (X.Tracebacks (J))), Info, Ptr); |
| exit when J = X.Num_Tracebacks; |
| Append_Info_String (" ", Info, Ptr); |
| end loop; |
| |
| Append_Info_NL (Info, Ptr); |
| end if; |
| |
| return Info (1 .. Ptr); |
| end Basic_Exception_Traceback; |
| |
| --------------------------- |
| -- Exception_Information -- |
| --------------------------- |
| |
| -- The format of the string is: |
| |
| -- Exception_Name: nnnnn |
| -- Message: mmmmm |
| -- PID: ppp |
| -- Call stack traceback locations: |
| -- 0xhhhh 0xhhhh 0xhhhh ... 0xhhh |
| |
| -- where |
| |
| -- nnnn is the fully qualified name of the exception in all upper |
| -- case letters. This line is always present. |
| |
| -- mmmm is the message (this line present only if message is non-null) |
| |
| -- ppp is the Process Id value as a decimal integer (this line is |
| -- present only if the Process Id is non-zero). Currently we are |
| -- not making use of this field. |
| |
| -- The Call stack traceback locations line and the following values |
| -- are present only if at least one traceback location was recorded. |
| -- the values are given in C style format, with lower case letters |
| -- for a-f, and only as many digits present as are necessary. |
| |
| -- The line terminator sequence at the end of each line, including the |
| -- last line is a CR-LF sequence (16#0D# followed by 16#0A#). |
| |
| -- The Exception_Name and Message lines are omitted in the abort |
| -- signal case, since this is not really an exception, and the only |
| -- use of this routine is internal for printing termination output. |
| |
| -- WARNING: if the format of the generated string is changed, please note |
| -- that an equivalent modification to the routine String_To_EO must be |
| -- made to preserve proper functioning of the stream attributes. |
| |
| function Exception_Information (X : Exception_Occurrence) return String is |
| |
| -- This information is now built using the circuitry introduced in |
| -- association with the support of traceback decorators, as the |
| -- catenation of the exception basic information and the call chain |
| -- backtrace in its basic form. |
| |
| Basic_Info : constant String := Basic_Exception_Information (X); |
| Tback_Info : constant String := Basic_Exception_Traceback (X); |
| |
| Basic_Len : constant Natural := Basic_Info'Length; |
| Tback_Len : constant Natural := Tback_Info'Length; |
| |
| Info : String (1 .. Basic_Len + Tback_Len); |
| Ptr : Natural := 0; |
| |
| begin |
| Append_Info_String (Basic_Info, Info, Ptr); |
| Append_Info_String (Tback_Info, Info, Ptr); |
| |
| return Info; |
| end Exception_Information; |
| |
| |
| ------------------------- |
| -- Set_Exception_C_Msg -- |
| ------------------------- |
| |
| procedure Set_Exception_C_Msg |
| (Id : Exception_Id; |
| Msg1 : Big_String_Ptr; |
| Line : Integer := 0; |
| Msg2 : Big_String_Ptr := null) |
| is |
| Excep : constant EOA := Get_Current_Excep.all; |
| Val : Integer := Line; |
| Remind : Integer; |
| Size : Integer := 1; |
| Ptr : Natural; |
| |
| begin |
| Exception_Propagation.Setup_Exception (Excep, Excep); |
| Excep.Exception_Raised := False; |
| Excep.Id := Id; |
| Excep.Num_Tracebacks := 0; |
| Excep.Pid := Local_Partition_ID; |
| Excep.Msg_Length := 0; |
| Excep.Cleanup_Flag := False; |
| |
| while Msg1 (Excep.Msg_Length + 1) /= ASCII.NUL |
| and then Excep.Msg_Length < Exception_Msg_Max_Length |
| loop |
| Excep.Msg_Length := Excep.Msg_Length + 1; |
| Excep.Msg (Excep.Msg_Length) := Msg1 (Excep.Msg_Length); |
| end loop; |
| |
| -- Append line number if present |
| |
| if Line > 0 then |
| |
| -- Compute the number of needed characters |
| |
| while Val > 0 loop |
| Val := Val / 10; |
| Size := Size + 1; |
| end loop; |
| |
| -- If enough characters are available, put the line number |
| |
| if Excep.Msg_Length <= Exception_Msg_Max_Length - Size then |
| Excep.Msg (Excep.Msg_Length + 1) := ':'; |
| Excep.Msg_Length := Excep.Msg_Length + Size; |
| Val := Line; |
| Size := 0; |
| |
| while Val > 0 loop |
| Remind := Val rem 10; |
| Val := Val / 10; |
| Excep.Msg (Excep.Msg_Length - Size) := |
| Character'Val (Remind + Character'Pos ('0')); |
| Size := Size + 1; |
| end loop; |
| end if; |
| end if; |
| |
| -- Append second message if present |
| |
| if Msg2 /= null |
| and then Excep.Msg_Length + 1 < Exception_Msg_Max_Length |
| then |
| Excep.Msg_Length := Excep.Msg_Length + 1; |
| Excep.Msg (Excep.Msg_Length) := ' '; |
| |
| Ptr := 1; |
| while Msg2 (Ptr) /= ASCII.NUL |
| and then Excep.Msg_Length < Exception_Msg_Max_Length |
| loop |
| Excep.Msg_Length := Excep.Msg_Length + 1; |
| Excep.Msg (Excep.Msg_Length) := Msg2 (Ptr); |
| Ptr := Ptr + 1; |
| end loop; |
| end if; |
| end Set_Exception_C_Msg; |
| |
| ----------------------- |
| -- Set_Exception_Msg -- |
| ----------------------- |
| |
| procedure Set_Exception_Msg |
| (Id : Exception_Id; |
| Message : String) |
| is |
| Len : constant Natural := |
| Natural'Min (Message'Length, Exception_Msg_Max_Length); |
| First : constant Integer := Message'First; |
| Excep : constant EOA := Get_Current_Excep.all; |
| |
| begin |
| Exception_Propagation.Setup_Exception (Excep, Excep); |
| Excep.Exception_Raised := False; |
| Excep.Msg_Length := Len; |
| Excep.Msg (1 .. Len) := Message (First .. First + Len - 1); |
| Excep.Id := Id; |
| Excep.Num_Tracebacks := 0; |
| Excep.Pid := Local_Partition_ID; |
| Excep.Cleanup_Flag := False; |
| |
| end Set_Exception_Msg; |
| |
| ---------------------------------- |
| -- Tailored_Exception_Traceback -- |
| ---------------------------------- |
| |
| function Tailored_Exception_Traceback |
| (X : Exception_Occurrence) return String |
| is |
| -- We indeed reference the decorator *wrapper* from here and not the |
| -- decorator itself. The purpose of the local variable Wrapper is to |
| -- prevent a potential crash by race condition in the code below. The |
| -- atomicity of this assignment is enforced by pragma Atomic in |
| -- System.Soft_Links. |
| |
| -- The potential race condition here, if no local variable was used, |
| -- relates to the test upon the wrapper's value and the call, which |
| -- are not performed atomically. With the local variable, potential |
| -- changes of the wrapper's global value between the test and the |
| -- call become inoffensive. |
| |
| Wrapper : constant Traceback_Decorator_Wrapper_Call := |
| Traceback_Decorator_Wrapper; |
| |
| begin |
| if Wrapper = null then |
| return Basic_Exception_Traceback (X); |
| else |
| return Wrapper.all (X.Tracebacks'Address, X.Num_Tracebacks); |
| end if; |
| end Tailored_Exception_Traceback; |
| |
| ------------------------------------ |
| -- Tailored_Exception_Information -- |
| ------------------------------------ |
| |
| function Tailored_Exception_Information |
| (X : Exception_Occurrence) return String |
| is |
| -- The tailored exception information is simply the basic information |
| -- associated with the tailored call chain backtrace. |
| |
| Basic_Info : constant String := Basic_Exception_Information (X); |
| Tback_Info : constant String := Tailored_Exception_Traceback (X); |
| |
| Basic_Len : constant Natural := Basic_Info'Length; |
| Tback_Len : constant Natural := Tback_Info'Length; |
| |
| Info : String (1 .. Basic_Len + Tback_Len); |
| Ptr : Natural := 0; |
| |
| begin |
| Append_Info_String (Basic_Info, Info, Ptr); |
| Append_Info_String (Tback_Info, Info, Ptr); |
| |
| return Info; |
| end Tailored_Exception_Information; |
| |
| procedure Tailored_Exception_Information |
| (X : Exception_Occurrence; |
| Buff : in out String; |
| Last : in out Integer) |
| is |
| begin |
| Append_Info_String (Basic_Exception_Information (X), Buff, Last); |
| Append_Info_String (Tailored_Exception_Traceback (X), Buff, Last); |
| end Tailored_Exception_Information; |
| |
| end Exception_Data; |
