LMDBG-RUN(1)LMDBG-RUN(1)NAMElmdbg-run - runs a program and traces the malloc/realloc/free calls
SYNOPSISlmdbg-run [OPTIONS] <progname> [args...]
DESCRIPTIONlmdbg-run lmdbg-run runs an external command progname args and creates
a log file where all invocations of malloc, calloc, realloc, memalign,
posix_memalign and free are registered accompanied by the following
information: full stacktrace (addresses), input argument(s) (requested
size and/or address), result value (returned address, if any) and ordi‐
nal number of function invocation. Also, some special information is
output about the program being run. Before being saved to the log
file, stacktrace info can be filtered through a custom command.
OPTIONS-h Display the help message.
-V Display the lmdbg version.
-v Enable verbose mode.
-o filename
Specify the log file name.
-f|-p command
Filter stacktraces through a filtering command/pipe. The result
is sent to the log file specified in -o option or to stdout oth‐
erwise.
-n Do not enable logging on startup. To enable it, send SIGUSR1
signal to the process.
-N filename
Save pid of progname to filename.
-T number
Specify the number of addresses to skip from the top of the
stacktrace (farther from function main).
-B number
Specify the number of addresses to skip from the bottom of the
stacktrace (nearer to function main).
-M number
Limit the number of addresses shown in a stacktrace. An incom‐
plete stacktrace may be generated, that includes the top of the
stack.
EXAMPLE
The output of lmdbg-run may look like the following
realloc ( 0xbb901800 , 777 ) --> 0xbb901c00
0xbbbe58e8
0xbbbe5a37
0x8048764
0x8048584
0x80484e7
This output means that realloc function was given the pointer
0xbb901800 and 777 bytes were requested. As a result realloc returned
the address 0xbb901c00. Addresses 0xbbbe58e8, 0xbbbe5a37 etc. are a
part of the stacktrace.
EXAMPLE
$ cat test2.c
#include <stdlib.h>
int main ()
{
void *p1 = NULL;
void *p2 = NULL;
p1 = malloc (555);
p2 = realloc (p2, 666);
p2 = realloc (p2, 777);
p2 = realloc (p2, 888);
return 0;
}
$ cc -O0 -g -o test2 test2.c
$ lmdbg-run-o log ./test2
$ cat log
info section 0x0xbbace000 0x0xbbbc6000 /lib/libc.so.12.179
info section 0x0xbbbdd000 0x0xbbbe1000 /usr/pkg/lib/liblmdbg.so.0.0
info section 0x0xbbbee000 0x0xbbbfe000 /libexec/ld.elf_so
info progname ./test2
malloc ( 555 ) --> 0xbb90a400 num: 1
0xbbbddb7a
0xbbbde53b
0x8048769
0x804863d
0x8048678
realloc ( NULL , 666 ) --> 0xbb90a800 num: 2
0xbbbddb7a
0xbbbde68c
0x8048781
0x804863d
0x8048678
realloc ( 0xbb90a800 , 777 ) --> 0xbb90ac00 num: 3
0xbbbddb7a
0xbbbde68c
0x8048799
0x804863d
0x8048678
realloc ( 0xbb90ac00 , 888 ) --> 0xbb90a800 num: 4
0xbbbddb7a
0xbbbde68c
0x80487b1
0x804863d
0x8048678
$
EXAMPLElmdbg-run-o log ./my_app &&
lmdbg-leaks log > log_leaks &&
lmdbg-sym ./my_app log_leaks > log_leaks2 &&
lmdbg-sysleaks -s log_leaks2 > log_final
lmdbg-run-B2 -M6 -f 'lmdbg-leaks | lmdbg-sym > log' ./my_app <args>
ENVIRONMENT
LMDBG_LIB
Path to LD_PRELOAD'ed liblmdbg dynamic library. It defaults to
/usr/local/lib/liblmdbg.so
NOTES
Full stacktrace allows analysing an application on per-module basis. It
helps determine what libraries and/or components require more memory
than others and why. See lmdbg-stat and lmdbg-sort.
BUGS
The current implementation of lmdbg-run relies on several GCC's exten‐
sions, namely, __builtin_return_address, __builtin_frame_address,
__attribute__((constructor)) and __attribute__((destructor)). In my
knowledge, Besides GCC these extensions are also supported by Intel C
compiler and Clang. If you know a solution that works for other compil‐
ers let me now ;-)
SEE ALSOlmdbg(1), lmdbg-sym(1), lmdbg-stat(1), lmdbg-sort(1), lmdbg-grep(1),
lmdbg-head(1), lmdbg-leaks(1), lmdbg-sysleaks(1), lmdbg-strip(1),
lmdbg-modules(1)AUTHOR
Aleksey Cheusov <vle@gmx.net>
Aug 4, 2013 LMDBG-RUN(1)
