1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- V X A D D R 2 L I N E --
9 -- Copyright (C) 2002, 2003 Ada Core Technologies, Inc. --
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 2, 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 -- This program is meant to be used with vxworks to compute symbolic
28 -- backtraces on the host from non-symbolic backtraces obtained on the target.
30 -- The basic idea is to automate the computation of the necessary address
31 -- adjustments prior to calling addr2line when the application has only been
32 -- partially linked on the host.
34 -- Variants for various targets are supported, and the command line should
37 -- <target>-addr2line [-a <target_arch>] <exe_file> <ref_address>
38 -- <backtrace addresses>
42 -- selects the target architecture. In the absence of this parameter the
43 -- default variant is chosen based on the Detect_Arch result. Generally,
44 -- this parameter will only be used if vxaddr2line is recompiled manually.
45 -- Otherwise, the command name will always be of the form
46 -- <target>-vxaddr2line where there is no ambiguity on the target's
50 -- The name of the partially linked binary file for the application.
53 -- Runtime address (on the target) of a reference symbol you choose,
54 -- which name shall match the value of the Ref_Symbol variable declared
55 -- below. A symbol with a small offset from the beginning of the text
56 -- segment is better, so "adainit" is a good choice.
58 -- <backtrace addresses> :
59 -- The call chain addresses you obtained at run time on the target and
60 -- for which you want a symbolic association.
62 -- TO ADD A NEW ARCHITECTURE add an appropriate value to Architecture type
63 -- (in a format <host>_<target>), and then an appropriate value to Config_List
66 with Text_IO; use Text_IO;
67 with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
68 with Ada.Command_Line; use Ada.Command_Line;
69 with Ada.Strings.Fixed; use Ada.Strings.Fixed;
71 with GNAT.OS_Lib; use GNAT.OS_Lib;
72 with GNAT.Directory_Operations; use GNAT.Directory_Operations;
73 with GNAT.Expect; use GNAT.Expect;
74 with GNAT.Regpat; use GNAT.Regpat;
76 procedure VxAddr2Line is
78 Ref_Symbol : String := "adainit";
79 -- This is the name of the reference symbol which runtime address shall
80 -- be provided as the <ref_address> argument.
82 -- All supported architectures
89 type Arch_Record is record
90 Addr2line_Binary : String_Access;
91 -- Name of the addr2line utility to use.
93 Nm_Binary : String_Access;
94 -- Name of the host nm utility, which will be used to find out the
95 -- offset of the reference symbol in the text segment of the partially
98 Addr_Digits_To_Skip : Integer;
99 -- When addresses such as 0xfffffc0001dfed50 are provided, for instance
100 -- on ALPHA, indicate the number of leading digits that can be ignored,
101 -- which will avoid computational overflows. Typically only useful when
102 -- 64bit addresses are provided.
104 Bt_Offset_From_Call : Integer;
105 -- Offset from a backtrace address to the address of the corresponding
106 -- call instruction. This should always be 0, except on platforms where
107 -- the backtrace addresses actually correspond to return and not call
108 -- points. In such cases, a negative value is most likely.
111 -- Configuration for each of the architectures
112 Arch_List : array (Architecture'Range) of Arch_Record :=
114 (Addr2line_Binary => null,
116 Addr_Digits_To_Skip => 0,
117 Bt_Offset_From_Call => -4),
119 (Addr2line_Binary => null,
121 Addr_Digits_To_Skip => 0,
122 Bt_Offset_From_Call => -4),
124 (Addr2line_Binary => null,
126 Addr_Digits_To_Skip => 0,
127 Bt_Offset_From_Call => 0),
129 (Addr2line_Binary => null,
131 Addr_Digits_To_Skip => 8,
132 Bt_Offset_From_Call => 0)
135 -- Current architecture
136 Cur_Arch : Architecture;
138 -- State of architecture detection
139 Detect_Success : Boolean := False;
141 -----------------------
142 -- Local subprograms --
143 -----------------------
145 procedure Error (Msg : String);
146 pragma No_Return (Error);
147 -- Prints the message and then terminates the program
150 -- Displays the short help message and then terminates the program
152 function Get_Reference_Offset return Integer;
153 -- Computes the static offset of the reference symbol by calling nm
155 function Get_Value_From_Hex_Arg (Arg : Natural) return Integer;
156 -- Threats the argument number Arg as a C-style hexadecimal literal
157 -- and returns its integer value
159 function Hex_Image (Value : Integer) return String_Access;
160 -- Returns access to a string that contains hexadecimal image of Value
162 -- Separate functions that provide build-time customization:
164 procedure Detect_Arch;
165 -- Saves in Cur_Arch the current architecture, based on the name of
166 -- vxaddr2line instance and properties of the host. Detect_Success is False
167 -- if detection fails
173 procedure Detect_Arch is
174 Name : String := Base_Name (Command_Name);
175 Proc : String := Name (Name'First .. Index (Name, "-") - 1);
176 Target : String := Name (Name'First .. Index (Name, "vxaddr2line") - 1);
179 Detect_Success := False;
185 if Proc = "alpha" then
186 Cur_Arch := DEC_ALPHA;
188 -- Let's detect the host.
189 -- ??? A naive implementation that can't distinguish between Unixes
190 if Directory_Separator = '/' then
191 Cur_Arch := Architecture'Value ("solaris_" & Proc);
193 Cur_Arch := Architecture'Value ("windows_" & Proc);
197 if Arch_List (Cur_Arch).Addr2line_Binary = null then
198 Arch_List (Cur_Arch).Addr2line_Binary := new String'
199 (Target & "addr2line");
201 if Arch_List (Cur_Arch).Nm_Binary = null then
202 Arch_List (Cur_Arch).Nm_Binary := new String'
206 Detect_Success := True;
218 procedure Error (Msg : String) is
226 --------------------------
227 -- Get_Reference_Offset --
228 --------------------------
230 function Get_Reference_Offset return Integer is
231 Nm_Cmd : constant String_Access :=
232 Locate_Exec_On_Path (Arch_List (Cur_Arch).Nm_Binary.all);
234 Nm_Args : Argument_List :=
236 new String'(Argument (1)));
238 Forever : aliased String := "^@@@@";
239 Reference : aliased String := Ref_Symbol & "\s+\S\s+([\da-fA-F]+)";
241 Pd : Process_Descriptor;
242 Result : Expect_Match;
245 -- If Nm is not found, abort
247 if Nm_Cmd = null then
248 Error ("Couldn't find " & Arch_List (Cur_Arch).Nm_Binary.all);
252 (Pd, Nm_Cmd.all, Nm_Args, Buffer_Size => 0, Err_To_Out => True);
254 -- Expect a string containing the reference symbol
257 Regexp_Array'(1 => Reference'Unchecked_Access),
260 -- If we are here, the pattern was matched successfully
263 Match_String : String := Expect_Out_Match (Pd);
264 Matches : Match_Array (0 .. 1);
268 Match (Reference, Match_String, Matches);
269 Value := Integer'Value
271 & Match_String (Matches (1).First .. Matches (1).Last) & "#");
273 -- Expect a string that will never be emitted, so that the
274 -- process can be correctly terminated (with Process_Died)
277 Regexp_Array'(1 => Forever'Unchecked_Access),
285 -- We can not get here
290 when Invalid_Process =>
291 Error ("Could not spawn a process " & Nm_Cmd.all);
295 -- The process died without matching the reference symbol or the
296 -- format wasn't recognized.
298 Error ("Unexpected output from " & Nm_Cmd.all);
299 end Get_Reference_Offset;
301 ----------------------------
302 -- Get_Value_From_Hex_Arg --
303 ----------------------------
305 function Get_Value_From_Hex_Arg (Arg : Natural) return Integer is
307 Cur_Arg : String := Argument (Arg);
310 -- Skip "0x" prefix if present
312 if Cur_Arg'Length > 2 and then Cur_Arg (1 .. 2) = "0x" then
318 -- Add architecture-specific offset
320 Offset := Offset + Arch_List (Cur_Arch).Addr_Digits_To_Skip;
324 return Integer'Value ("16#" & Cur_Arg (Offset .. Cur_Arg'Last) & "#");
325 end Get_Value_From_Hex_Arg;
331 function Hex_Image (Value : Integer) return String_Access is
332 Result : String (1 .. 20);
336 Put (Result, Value, 16);
337 Start_Pos := Index (Result, "16#") + 3;
338 return new String'(Result (Start_Pos .. Result'Last - 1));
347 Put_Line ("Usage : " & Base_Name (Command_Name)
349 & Ref_Symbol & " offset on target> <addr1> ...");
354 Ref_Static_Offset, Ref_Runtime_Address, Bt_Address : Integer;
356 Addr2line_Cmd : String_Access;
358 Addr2line_Args : Argument_List (1 .. 501);
359 -- We expect that there won't be more than 500 backtrace frames
361 Addr2line_Args_Count : Natural;
365 -- Start of processing for VxAddr2Line
371 -- There should be at least two arguments
373 if Argument_Count < 2 then
377 -- ??? HARD LIMIT! There should be at most 501 arguments
379 if Argument_Count > 501 then
380 Error ("Too many backtrace frames");
383 -- Do we have a valid architecture?
385 if not Detect_Success then
386 Put_Line ("Couldn't detect the architecture");
391 Locate_Exec_On_Path (Arch_List (Cur_Arch).Addr2line_Binary.all);
393 -- If Addr2line is not found, abort
395 if Addr2line_Cmd = null then
396 Error ("Couldn't find " & Arch_List (Cur_Arch).Addr2line_Binary.all);
399 -- The first argument specifies the image file. Check if it exists.
401 if not Is_Regular_File (Argument (1)) then
402 Error ("Couldn't find the executable " & Argument (1));
405 -- The second argument specifies the reference symbol runtime address.
406 -- Let's parse and store it
408 Ref_Runtime_Address := Get_Value_From_Hex_Arg (2);
410 -- Run nm command to get the reference symbol static offset
412 Ref_Static_Offset := Get_Reference_Offset;
414 -- Build addr2line parameters. First, the standard part
416 Addr2line_Args (1) := new String'("--exe=" & Argument (1));
417 Addr2line_Args_Count := 1;
419 -- Now, append to this the adjusted backtraces in arguments 4 and further
421 for J in 3 .. Argument_Count loop
423 -- Basically, for each address in the runtime backtrace ...
425 -- o We compute its offset relatively to the runtime address of the
430 -- o We add this offset to the static one for the reference symbol in
431 -- the executable to find the executable offset corresponding to the
432 -- backtrace address.
434 Bt_Address := Get_Value_From_Hex_Arg (J);
437 Bt_Address - Ref_Runtime_Address
439 + Arch_List (Cur_Arch).Bt_Offset_From_Call;
441 Addr2line_Args_Count := Addr2line_Args_Count + 1;
442 Addr2line_Args (Addr2line_Args_Count) := Hex_Image (Bt_Address);
445 -- Run the resulting command
447 Spawn (Addr2line_Cmd.all,
448 Addr2line_Args (1 .. Addr2line_Args_Count), Success);
453 -- Mask all exceptions