------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- S Y S T E M . M E M O R Y -- -- -- -- S p e c -- -- -- -- -- -- Copyright (C) 2001 Free Software Foundation, Inc. -- -- -- -- This specification is derived from the Ada Reference Manual for use with -- -- GNAT. The copyright notice above, and the license provisions that follow -- -- apply solely to the contents of the part following the private keyword. -- -- -- -- 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. -- -- -- ------------------------------------------------------------------------------ -- This version contains allocation tracking capability. -- The object file corresponding to this instrumented version is to be found -- in libgmem. -- When enabled, the subsystem logs all the calls to __gnat_malloc and -- __gnat_free. This log can then be processed by gnatmem to detect -- dynamic memory leaks. -- -- To use this functionality, you must compile your application with -g -- and then link with this object file: -- -- gnatmake -g program -largs -lgmem -- -- After compilation, you may use your program as usual except that upon -- completion, it will generate in the current directory the file gmem.out. -- -- You can then investigate for possible memory leaks and mismatch by calling -- gnatmem with this file as an input: -- -- gnatmem -i gmem.out program -- -- See gnatmem section in the GNAT User's Guide for more details. -- -- NOTE: This capability is currently supported on the following targets: -- -- Windows -- GNU/Linux -- HP-UX -- Irix -- Solaris -- Tru64 pragma Source_File_Name (System.Memory, Body_File_Name => "memtrack.adb"); with Ada.Exceptions; with System.Soft_Links; with System.Traceback; package body System.Memory is use Ada.Exceptions; use System.Soft_Links; use System.Traceback; function c_malloc (Size : size_t) return System.Address; pragma Import (C, c_malloc, "malloc"); procedure c_free (Ptr : System.Address); pragma Import (C, c_free, "free"); function c_realloc (Ptr : System.Address; Size : size_t) return System.Address; pragma Import (C, c_realloc, "realloc"); type File_Ptr is new System.Address; function fopen (Path : String; Mode : String) return File_Ptr; pragma Import (C, fopen); procedure fwrite (Ptr : System.Address; Size : size_t; Nmemb : size_t; Stream : File_Ptr); procedure fwrite (Str : String; Size : size_t; Nmemb : size_t; Stream : File_Ptr); pragma Import (C, fwrite); procedure fputc (C : Integer; Stream : File_Ptr); pragma Import (C, fputc); procedure fclose (Stream : File_Ptr); pragma Import (C, fclose); procedure Finalize; -- Replace the default __gnat_finalize to properly close the log file. pragma Export (C, Finalize, "__gnat_finalize"); Address_Size : constant := System.Address'Max_Size_In_Storage_Elements; -- Size in bytes of a pointer Max_Call_Stack : constant := 200; -- Maximum number of frames supported Skip_Frame : constant := 1; -- Number of frames to remove from the call stack to hide functions from -- this unit. Tracebk : aliased array (0 .. Max_Call_Stack) of System.Address; Num_Calls : aliased Integer := 0; -- Store the current call stack from Alloc and Free Gmemfname : constant String := "gmem.out" & ASCII.NUL; -- Allocation log of a program is saved in a file gmem.out -- ??? What about Ada.Command_Line.Command_Name & ".out" instead of static -- gmem.out Gmemfile : File_Ptr; -- Global C file pointer to the allocation log procedure Gmem_Initialize; -- Initialization routine; opens the file and writes a header string. This -- header string is used as a magic-tag to know if the .out file is to be -- handled by GDB or by the GMEM (instrumented malloc/free) implementation. ----------- -- Alloc -- ----------- function Alloc (Size : size_t) return System.Address is Result : aliased System.Address; Actual_Size : aliased size_t := Size; begin if Size = size_t'Last then Raise_Exception (Storage_Error'Identity, "object too large"); end if; -- Change size from zero to non-zero. We still want a proper pointer -- for the zero case because pointers to zero length objects have to -- be distinct, but we can't just go ahead and allocate zero bytes, -- since some malloc's return zero for a zero argument. if Size = 0 then Actual_Size := 1; end if; Lock_Task.all; Result := c_malloc (Actual_Size); -- Logs allocation call -- format is: -- 'A' <mem addr> <size chunk> <len backtrace> <addr1> ... <addrn> Gmem_Initialize; Call_Chain (Tracebk'Address, Max_Call_Stack, Num_Calls); Num_Calls := Num_Calls - Skip_Frame; fputc (Character'Pos ('A'), Gmemfile); fwrite (Result'Address, Address_Size, 1, Gmemfile); fwrite (Actual_Size'Address, size_t'Max_Size_In_Storage_Elements, 1, Gmemfile); fwrite (Num_Calls'Address, Integer'Max_Size_In_Storage_Elements, 1, Gmemfile); fwrite (Tracebk (Skip_Frame)'Address, Address_Size, size_t (Num_Calls), Gmemfile); Unlock_Task.all; if Result = System.Null_Address then Raise_Exception (Storage_Error'Identity, "heap exhausted"); end if; return Result; end Alloc; -------------- -- Finalize -- -------------- Needs_Init : Boolean := True; -- Reset after first call to Gmem_Initialize procedure Finalize is begin if not Needs_Init then fclose (Gmemfile); end if; end Finalize; ---------- -- Free -- ---------- procedure Free (Ptr : System.Address) is Addr : aliased constant System.Address := Ptr; begin Lock_Task.all; -- Logs deallocation call -- format is: -- 'D' <mem addr> <len backtrace> <addr1> ... <addrn> Gmem_Initialize; Call_Chain (Tracebk'Address, Max_Call_Stack, Num_Calls); Num_Calls := Num_Calls - Skip_Frame; fputc (Character'Pos ('D'), Gmemfile); fwrite (Addr'Address, Address_Size, 1, Gmemfile); fwrite (Num_Calls'Address, Integer'Max_Size_In_Storage_Elements, 1, Gmemfile); fwrite (Tracebk (Skip_Frame)'Address, Address_Size, size_t (Num_Calls), Gmemfile); c_free (Ptr); Unlock_Task.all; end Free; --------------------- -- Gmem_Initialize -- --------------------- procedure Gmem_Initialize is begin if Needs_Init then Needs_Init := False; Gmemfile := fopen (Gmemfname, "wb" & ASCII.NUL); fwrite ("GMEM DUMP" & ASCII.LF, 10, 1, Gmemfile); end if; end Gmem_Initialize; ------------- -- Realloc -- ------------- function Realloc (Ptr : System.Address; Size : size_t) return System.Address is Result : System.Address; begin if Size = size_t'Last then Raise_Exception (Storage_Error'Identity, "object too large"); end if; Abort_Defer.all; Result := c_realloc (Ptr, Size); Abort_Undefer.all; if Result = System.Null_Address then Raise_Exception (Storage_Error'Identity, "heap exhausted"); end if; return Result; end Realloc; end System.Memory;