RHEL6 で頭の痛い問題を引き起こしているこの小さな関数があり、何が起こっているのかわかりません...そしてデバッグが面倒です。これを実行すると STORAGE_ERROR が発生するので、gstack を実行して、プログラムがハングしている場所を確認しました (以下を参照)。memcmp の問題のように見えますが、どこでどのように呼び出されているのかわかりません..回避策のアイデアはありますか?
この関数を単に「true」を返すように変更すると、正常に動作するように見えるので (STORAGE_ERROR は消えます)、問題はこの部分のロジックにあると考えます: (Ada.Characters.Handling.To_Upper(EPS_List(1). all) = "LOCALHOST");
function Localhost_Only return Boolean is
--++
EPS_List : String_List_Type
:= Values(Bstring.To_Bounded_String("EPS"));
begin
return (Ada.Characters.Handling.To_Upper(EPS_List(1).all) = "LOCALHOST");
end Localhost_Only;
編集開始***
別の方法でこれを行っていました (関数スコープの外に移動する...なぜこれが機能するのですか?):
EPS_List : String_List_Type
:= Values(Bstring.To_Bounded_String("EPS"));
function Localhost_Only return Boolean is
--++
begin
return (Ada.Characters.Handling.To_Upper(EPS_List(1).all) = "LOCALHOST");
end Localhost_Only;
編集終了***
プロセスのgstack出力:
Thread 1 (Thread 0x407059a0 (LWP 13610)):
#0 0x40000424 in __kernel_vsyscall ()
#1 0x00b2b2fc in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2 0x0b53dd9e in system__tasking__stages__vulnerable_complete_master ()
#3 0x0b53e242 in system__tasking__stages__finalize_global_tasks ()
#4 0x0b5845d3 in __gnat_last_chance_handler ()
#5 0x0b545c50 in ada__exceptions__exception_traces__unhandled_exception_terminateXn ()
#6 0x0b5459de in ada__exceptions__exception_propagation__propagate_exceptionXn ()
#7 0x0b5465c5 in __gnat_raise_nodefer_with_msg ()
#8 0x0b5469ed in ada__exceptions__raise_with_location_and_msg ()
#9 0x0b5469b8 in __gnat_raise_storage_error_msg ()
#10 0x0b546f98 in __gnat_rcheck_31 ()
#11 0x0b5363de in system__interrupt_management__notify_exception ()
#12 <signal handler called>
#13 0x0bcef590 in memcmp@@GLIBC_2.0 ()
#14 0x084a83c9 in common_network_configuration__localhost_only ()
関連するタイプ/機能:
type Number_Of_Items_Type is range 0 .. 250;
subtype Index_Type is Number_Of_Items_Type
range Number_Of_Items_Type'First + 1 .. Number_Of_Items_Type'Last;
type String_List_Type is array (Index_Type range <>)
of String_Access.String_P_Type;
package Bstring is new Ada.Strings.Bounded.Generic_Bounded_Length
(Max => Line_Length_Type'last);
function Values(Name : Bstring.Bounded_String) return String_List_Type is
--++
-- ABSTRACT
-- Return a list of pointers to strings. The strings are all the values
-- associated with the specified name. All values are recursively
-- evaluated so that each entry in the returned list is a primitive
-- name (i.e. integer, ip_address, or unix_workstation).
--
-- If a circular definition is detected, an empty list is returned.
--
-- LOCAL DATA
-- Number of items in list
Count : Number_Of_Items_Type := 0;
-- List of pointers to strings containing the primitive values
Out_List : String_List_Type (1 .. Index_Type'Last);
-- The Index of the item being evaluated
Item : Config_Index_Type := 0;
-- A safety net, to detect and prevent unlimited recursion, such as
-- will happen in the case of a circular definition.
Depth : Number_Of_Items_Type := 0;
procedure Find_Values (Name : in Bstring.Bounded_String) is
--++
-- ABSTRACT
-- This procedure recursively calls itself until it makes it all
-- The way through the Config_Array without finding a match on the
-- specified Name. The index of the last name for which a match was
-- found is used to get the value associated with that Name. This
-- is a primitive value associated with the name and is added to the
-- Out_List.
--
-- Depth is used to count the recursion depth, when it reaches a
-- maximum, no more recursive calls are made, preventing an endless
-- loop in the case of a direct or indirect circular definition.
begin
Depth := Depth + 1;
for Index in 1 .. Config_Count loop
if Name_Match(Bstring.To_String(Name),Index)
and Count < Number_Of_Items_Type'last
and Depth < Number_Of_Items_Type'last then
Item := Index;
Find_Values (Config_Array(Index).Value);
end if;
end loop;
if Item /= 0 then
if Count < Number_Of_Items_Type'last then
Count := Count + 1;
Out_List(Count) := Config_Array(Item).Val_Ptr;
end if;
Item := 0;
end if;
end Find_Values;
begin -- Values
Find_Values(Name);
if Depth < Number_Of_Items_Type'last then
return Out_List(1..Count);
else
return Null_String_List;
end if;
end Values;