Hi -<div><br></div><div>Sorry for the delayed response. Very busy few days. You need to specify on the command line the name of the symbol you want to trace. I'm actually not sure if -c works with libdl symbols, but I THINK it does. Please let me know. If not, I can fix it.</div>
<div><br></div><div>You name the symbol on the command line with -x, so for example I usually use ltrace like this:</div><div><br></div><div>ltrace -ttTgx functionB -x functionC -x functionD</div><div><br></div><div>tt - prefix line with time of day in microsecs</div>
<div>T - amount of time spent in the call</div><div>g - an option I added to tell ltrace NOT to trace libc -- tracing libc can be noisy and annoying</div><div>x - the symbol name I want to trace</div><div><br></div><div>x will look for the symbol name in the binary and all currently linked libraries (i.e. if you ltrace attached after dlsym, it'll pick it up just fine) and if nothing is found it'll listen and attach when the symbol is dlsym'd later (i.e. if you start your application with ltrace and dlsym hasnt happened yet).</div>
<div><br></div><div>let me know if it works for you --</div><div>joe</div><meta charset="utf-8"><div><br><div class="gmail_quote">On Tue, Mar 30, 2010 at 1:13 PM, Rodrigo Dominguez <span dir="ltr"><<a href="mailto:roddomi@hotmail.com">roddomi@hotmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div>
Joe,<br>
<br>
Option 2 below compiles on my system. However, I am not sure I am
getting the libdl features you added. I wrote a small test program that
uses dlopen to load a library file I created (libB.so):<br>
<br>
#include <dlfcn.h><br>
<br>
int main(void)<br>
{<br>
void *handle;<br>
int (*myFunctionB)(void);<br>
<br>
handle = dlopen("./libB.so", RTLD_LAZY);<br>
myFunctionB = dlsym(handle, "functionB");<br>
(*myFunctionB)();<br>
<br>
return 0;<br>
}<br>
<br>Neither the system ltrace nor your ltrace show the call to functionB. This is the output:<br>
<br>
$ ltrace -c ./a.out<br>
Inside libB::functionB<br>
% time seconds usecs/call calls function<br>
------ ----------- ----------- --------- --------------------<br>
99.36 0.003254 3254 1 dlopen<br>
0.64 0.000021 21 1 dlsym<br>
------ ----------- ----------- --------- --------------------<br>
100.00 0.003275 2 total<br>
<br>
Am I missing something? Or am I misunderstanding the libdl support you added?<br>
<br>
Thank you.<br><br><hr>Date: Tue, 30 Mar 2010 11:53:02 -0700<div class="im"><br>Subject: Re: [Ltrace-devel] Tracing dependent libraries<br></div>From: <a href="mailto:ice799@gmail.com" target="_blank">ice799@gmail.com</a><br>
To: <a href="mailto:roddomi@hotmail.com" target="_blank">roddomi@hotmail.com</a>; <a href="mailto:ltrace-devel@lists.alioth.debian.org" target="_blank">ltrace-devel@lists.alioth.debian.org</a><div><div></div><div class="h5">
<br><br>Replying to this on-list just incase other people have this problem.<div><br></div><div>Not sure if I ever submit this patch back to the list, but I added support for backtraces so you can see the function call stack for traced functions.</div>
<div><br></div><div>The problem with this feature is that I didn't take the time to fix the configure script so that it would disable that code if you don't have libunwind on your system.</div><div><br></div><div>
There are two solutions:</div><div><br></div><div>1.) The simplest solution (until I or some one else fixes the configure script) is to install libunwind library and header files on your system and try building my branch again.</div>
<div><br></div><div>or</div><div><br></div><div>2.) Rewind the source tree in git to before that commit was made. To do this you can just: git checkout a95f1 -b before_unwind</div><div><br></div><div>That will create a local branch called "before_unwind" (the first byte of the sha before the libunwind commit are a95f1).</div>
<div><br></div><div>The downside is that if you do this you lose some of the man page cleanup and a small bugfix.</div><div><br></div><div>Sorry for the pain.</div><div><br></div><div>joe</div><div><br><div>
On Tue, Mar 30, 2010 at 11:11 AM, Rodrigo Dominguez <span dir="ltr"><<a href="mailto:roddomi@hotmail.com" target="_blank">roddomi@hotmail.com</a>></span> wrote:<br><blockquote style="border-left:1px solid rgb(204, 204, 204);padding-left:1ex">
<div lang="EN-US">
<div>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">Thanks. I was able to checkout your code.</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">I am getting the following errors after ‘./configure
&& make’</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">make -C sysdeps/linux-gnu</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">make[1]: Entering directory
`/home/rdomingu/ltrace/sysdeps/linux-gnu'</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">gcc -Wall -g -O2 -iquote /home/rdomingu/ltrace -iquote
/home/rdomingu/ltrace/sysdeps/linux-gnu
-DSYSCONFDIR=\"/usr/local/etc\" -I /usr/include/libelf
-I/home/rdomingu/ltrace/sysdeps/linux-gnu/x86_64 -c -o events.o events.c</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">In file included from events.c:12:</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/common.h:1:23: error: libunwind.h: No such
file or directory</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">In file included from /home/rdomingu/ltrace/common.h:11,</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">
from events.c:12:</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/elf.h:4:18: error: gelf.h: No such file or
directory</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">In file included from /home/rdomingu/ltrace/common.h:11,</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">
from events.c:12:</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/elf.h:9: error: expected
specifier-qualifier-list before âElfâ</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/elf.h:50: error: expected â=â,
â,â, â;â, âasmâ or â__attribute__â
before âarch_plt_sym_valâ</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">In file included from events.c:12:</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/common.h:193: error: expected
specifier-qualifier-list before âunw_addr_space_tâ</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">In file included from events.c:12:</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/common.h:234: error: expected declaration
specifiers or â...â before âGElf_Symâ</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">/home/rdomingu/ltrace/common.h:236: error: expected
â)â before âaddrâ</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">make[1]: *** [events.o] Error 1</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">make[1]: Leaving directory
`/home/rdomingu/ltrace/sysdeps/linux-gnu'</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">make: *** [sysdeps/sysdep.o] Error 2</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<div style="border-style:none none none solid;border-color:-moz-use-text-color -moz-use-text-color -moz-use-text-color blue;border-width:medium medium medium 1.5pt;padding:0in 0in 0in 4pt">
<div>
<div style="border-style:solid none none;border-color:rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color;border-width:1pt medium medium;padding:3pt 0in 0in">
<p><b><span style="font-size:10pt">From:</span></b><span style="font-size:10pt"> Joe Damato
[mailto:<a href="mailto:ice799@gmail.com" target="_blank">ice799@gmail.com</a>] <br>
<b>Sent:</b> Tuesday, March 30, 2010 1:12 PM</span></p><div><div></div><div><br>
<b>To:</b> Rodrigo Dominguez<br>
<b>Cc:</b> <a href="mailto:ltrace-devel@lists.alioth.debian.org" target="_blank">ltrace-devel@lists.alioth.debian.org</a><br>
<b>Subject:</b> Re: [Ltrace-devel] Tracing dependent libraries</div></div><br>
</div>
</div><div><div></div><div>
<p> </p>
<p>Not a dumb question at all. My code isn't part of the
official repository, but it is on github at: git://<a href="http://github.com/ice799/ltrace.git" target="_blank">github.com/ice799/ltrace.git</a>
</p>
<div>
<p> </p>
</div>
<div>
<p>My code is in the branch "libdl"</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>So you should:</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>git clone git://<a href="http://github.com/ice799/ltrace.git" target="_blank">github.com/ice799/ltrace.git</a></p>
</div>
<div>
<p>git checkout -b libdl origin/libdl</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>and you will be sitting in the libdl branch.</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>You can take a look at the commits on that branch by doing
git log. If a particular commit interests you, you can git show <sha> to
look at the diff.</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>If you have any other questions/issues getting my code or
getting it to build feel free to email me off list.</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>joe</p>
</div>
<div>
<p> </p>
<div>
<p>On Tue, Mar 30, 2010 at 9:35 AM, Rodrigo Dominguez <<a href="mailto:roddomi@hotmail.com" target="_blank">roddomi@hotmail.com</a>>
wrote:</p>
<div>
<div>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">Joe,</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">I am sorry for the dumb question but how
do you checkout a branch from github. I am not familiar with git. I ran:</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">git clone git://<a href="http://git.debian.org/git/collab-maint/ltrace.git" target="_blank">git.debian.org/git/collab-maint/ltrace.git</a></span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">but this only gets me the master branch.</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)">Thank you.</span></p>
<p><span style="font-size:11pt;color:rgb(31, 73, 125)"> </span></p>
<div style="border-style:none none none solid;border-color:-moz-use-text-color -moz-use-text-color -moz-use-text-color blue;border-width:medium medium medium 1.5pt;padding:0in 0in 0in 4pt">
<div>
<div style="border-style:solid none none;border-color:rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color;border-width:1pt medium medium;padding:3pt 0in 0in">
<p><b><span style="font-size:10pt">From:</span></b><span style="font-size:10pt"> Joe
Damato [mailto:<a href="mailto:ice799@gmail.com" target="_blank">ice799@gmail.com</a>]
<br>
<b>Sent:</b> Tuesday, March 09, 2010 5:20 PM<br>
<b>To:</b> Rodrigo Dominguez<br>
<b>Cc:</b> <a href="mailto:ltrace-devel@lists.alioth.debian.org" target="_blank">ltrace-devel@lists.alioth.debian.org</a><br>
<b>Subject:</b> Re: [Ltrace-devel] Tracing dependent libraries</span></p>
</div>
</div>
<div>
<div>
<p> </p>
<p style="margin-bottom:12pt">I
implemented support for libdl and you can get that tree from github: <a href="http://github.com/ice799/ltrace/tree/libdl" target="_blank">http://github.com/ice799/ltrace/tree/libdl</a></p>
<div>
<p>I
have *not* implemented tracing calls from libraries to other libraries, though.
doing that should be pretty straightforward. i don't really have the cycles
right now to implement that in the near term but I am willing to point people
in the right direction if they are interested in implementing it.</p>
</div>
<div>
<p> </p>
</div>
<div>
<p>otherwise
as soon as i have time to do it (probably later this month), i can implement it.</p>
<div>
<p> </p>
</div>
<div>
<p>joe </p>
<div>
<p> </p>
</div>
<div>
<p>On
Tue, Mar 9, 2010 at 2:13 PM, Rodrigo Dominguez <<a href="mailto:roddomi@hotmail.com" target="_blank">roddomi@hotmail.com</a>>
wrote:</p>
<p>How
can I get ltrace to trace dependent libraries (libraries called from<br>
within libraries)? All I was able to find was this old post:<br>
<br>
<a href="http://sourceware.org/ml/binutils/2006-09/msg00009.html" target="_blank">http://sourceware.org/ml/binutils/2006-09/msg00009.html</a><br>
<br>
Has this been implemented since then?<br>
<br>
Thank you.<br>
<br>
<br>
_______________________________________________<br>
Ltrace-devel mailing list<br>
<a href="mailto:Ltrace-devel@lists.alioth.debian.org" target="_blank">Ltrace-devel@lists.alioth.debian.org</a><br>
<a href="http://lists.alioth.debian.org/mailman/listinfo/ltrace-devel" target="_blank">http://lists.alioth.debian.org/mailman/listinfo/ltrace-devel</a></p>
</div>
<p> </p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<p> </p>
</div>
</div></div></div>
</div>
</div>
</blockquote></div><br></div> </div></div></div>
</blockquote></div><br></div>