From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19513 invoked by alias); 20 Oct 2006 03:13:09 -0000 Received: (qmail 19502 invoked by uid 22791); 20 Oct 2006 03:13:08 -0000 X-Spam-Check-By: sourceware.org Received: from nevyn.them.org (HELO nevyn.them.org) (66.93.172.17) by sourceware.org (qpsmtpd/0.31.1) with ESMTP; Fri, 20 Oct 2006 03:13:05 +0000 Received: from drow by nevyn.them.org with local (Exim 4.54) id 1Gakoh-0002vc-6q; Thu, 19 Oct 2006 23:13:03 -0400 Date: Fri, 20 Oct 2006 03:13:00 -0000 From: Daniel Jacobowitz To: Ashwin Bharambe Cc: gdb@sourceware.org Subject: Re: Programmatic access to stack traces in C or C++ programs Message-ID: <20061020031303.GA11223@nevyn.them.org> Mail-Followup-To: Ashwin Bharambe , gdb@sourceware.org References: <3ef5826d0610191927n590c416fx238aa355a378d57c@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3ef5826d0610191927n590c416fx238aa355a378d57c@mail.gmail.com> User-Agent: Mutt/1.5.13 (2006-08-11) X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2006-10/txt/msg00151.txt.bz2 On Thu, Oct 19, 2006 at 10:27:08PM -0400, Ashwin Bharambe wrote: > Hi all, > > I wanted to create a "stacktrace library" which would provide a > routine to obtain the stacktrace of the program from any point > _programmatically_ (like Java's stacktraces, for example..) > > I was aware of libc's non-standard stacktrace API but it did not quite > work in many cases failing to resolve addresses, etc. It seems like > stacktrace functionality is quite implementation and > architecture-dependent. So, I was wondering if I could use portions of > gdb's code to create such a library. Currently, to print a stacktrace, > I utilize a piece of code (not mine, it's off the net) which fork()s a > gdb sub-process, makes it ptrace the parent and run the command > "backtrace". However this is quite time-consuming and sort of ugly. Your best bet for reliability is to work with libunwind, if you can restrict yourself to code with unwind information - which is more and more practical nowadays. > My question, therefore, is: are there pieces of the code I can steal > from libgdb to make this happen programmatically. I tried some naive > ways of performing gdb_init() and then having it execute the > 'backtrace' command (by invoking backtrace_command directly, for > example), however gdb says there's no stack. This seems to be the case > because it does not initialize its data structures without starting a > process. > > I would appreciate any pointers regarding how I can make gdb believe > the current process is the one it should use, without really > ptrace()ing it... You can not readily do this. It will be easier and faster to stick with forking another copy of GDB. -- Daniel Jacobowitz CodeSourcery