On Wed, Oct 13, 2010 at 9:39 PM, Artur Skawina <art.08.09(a)gmail.com> wrote:
> Wanted to use latrace on an app that was using setjmp/longjmp;
> and to avoid latrace causing a crash had to use the patch below.
>
> "latrace -Ap -n setjmp ..." was enough to make things work.
hi,
I was just working on a glibc fix for auditing vfork and sig/setjmp functions ;)
this is good workaround
>
> While doing this noticed the LA_SYMB_NOPLTEXIT omission for
> the '-s syms' case; not knowing if that was intentional i did
> not change that.
yea, I probably overlooked that.. however I checked glibc source and once
you return LA_SYMB_NOPLTENTER, pltexit is never called anyway.. but
I added it just in case glibc will fix this in the future.. thanks for noticing
it's nice to see someone is actually using this ;) thanks
jirka
ps ccing latrace list
>
> artur
>
>
> From: Artur Skawina <art.08.09(a)gmail.com>
> Date: Wed, 13 Oct 2010 18:42:57 +0000
> Subject: [PATCH] Add '-n' option, allowing to skip tracing certain symbols
>
> Makes it possible omit tracing just some calls, like 'setjmp'.
> ---
> doc/latrace.txt | 5 ++++-
> src/audit-init.c | 7 +++++++
> src/audit.c | 5 +++++
> src/config.c | 11 ++++++++++-
> src/config.h | 4 ++++
> 5 files changed, 30 insertions(+), 2 deletions(-)
>
> diff --git a/doc/latrace.txt b/doc/latrace.txt
> index b24742a..ab2044d 100644
> --- a/doc/latrace.txt
> +++ b/doc/latrace.txt
> @@ -10,7 +10,7 @@ latrace - LD_AUDIT 2.4+ libc frontend
>
> SYNOPSIS
> --------
> -*latrace* [-ltfsbcCpADaoyIiBdvTFELVh] command [arg ... ]
> +*latrace* [-ltfsnbcCpADaoyIiBdvTFELVh] command [arg ... ]
>
>
> DESCRIPTION
> @@ -45,6 +45,9 @@ OPTIONS
> *-s, --sym sym1[,sym2,...]*::
> audit symbols sym1, sym2 ...
>
> +*-n, --omit-sym sym1[,sym2,...]*::
> + omit symbols sym1, sym2 ...
> +
> *-S, --timestamp*::
> display timestamp for each symbol
>
> diff --git a/src/audit-init.c b/src/audit-init.c
> index 81ab1e5..322efe0 100644
> --- a/src/audit-init.c
> +++ b/src/audit-init.c
> @@ -189,6 +189,13 @@ int audit_init(int argc, char **argv, char **env)
> return -1;
> }
>
> + /* -n */
> + if ((*lt_sh(&cfg, skipsymbols)) &&
> + (-1 == (cfg.skipsymbols_cnt = get_names(&cfg, lt_sh(&cfg, skipsymbols), cfg.skipsymbols)))) {
> + printf("latrace failed to parse symbols to omit\n");
> + return -1;
> + }
> +
> /* -b */
> if ((*lt_sh(&cfg, flow_below)) &&
> (-1 == (cfg.flow_below_cnt = get_names(&cfg, lt_sh(&cfg, flow_below), cfg.flow_below)))) {
> diff --git a/src/audit.c b/src/audit.c
> index 2a97b75..2494d93 100644
> --- a/src/audit.c
> +++ b/src/audit.c
> @@ -234,6 +234,11 @@ static unsigned int la_symbind(const char *symname)
> flags = 0;
> }
>
> + if (cfg.skipsymbols_cnt) {
> + if (check_names((char*) symname, cfg.skipsymbols))
> + flags = LA_SYMB_NOPLTENTER|LA_SYMB_NOPLTEXIT;
> + }
> +
> return flags;
> }
>
> diff --git a/src/config.c b/src/config.c
> index 3f3145c..ba222d3 100644
> --- a/src/config.c
> +++ b/src/config.c
> @@ -34,6 +34,7 @@ static void usage()
> printf(" -t, --libs-to lib1,lib2... audit to lib1, lib2 ...\n");
> printf(" -f, --libs-from lib1,lib2... audit from lib1, lib2 ...\n");
> printf(" -s, --sym sym1,sym2... audit symbols sym1, sym2 ... \n");
> + printf(" -n, --omit-sym sym1,sym2... omit symbols sym1, sym2 ... \n");
> printf(" -L, --lib-subst s1,s2... objsearch LD_AUDIT interface (see man page)\n");
> printf("\n");
> printf(" -c, --counts display statistics counts of symbols\n");
> @@ -127,6 +128,7 @@ int lt_config(struct lt_config_app *cfg, int argc, char **argv)
> int option_index = 0;
> static struct option long_options[] = {
> {"sym", required_argument, 0, 's'},
> + {"omit-sym", required_argument, 0, 'n'},
> {"libs", required_argument, 0, 'l'},
> {"libs-to", required_argument, 0, 't'},
> {"libs-from", required_argument, 0, 'f'},
> @@ -157,7 +159,7 @@ int lt_config(struct lt_config_app *cfg, int argc, char **argv)
> {0, 0, 0, 0}
> };
>
> - c = getopt_long(argc, argv, "+s:l:t:f:vhi:BdISb:cC:y:YL:po:a:ADVTFERq",
> + c = getopt_long(argc, argv, "+s:n:l:t:f:vhi:BdISb:cC:y:YL:po:a:ADVTFERq",
> long_options, &option_index);
>
> if (c == -1)
> @@ -192,6 +194,13 @@ int lt_config(struct lt_config_app *cfg, int argc, char **argv)
> strncpy(lt_sh(cfg, symbols), optarg, strlen(optarg));
> break;
>
> + case 'n':
> + if (strlen(optarg) > LT_SYMBOLS_MAXSIZE)
> + return -1;
> +
> + strncpy(lt_sh(cfg, skipsymbols), optarg, strlen(optarg));
> + break;
> +
> case 'b':
> if (strlen(optarg) > LT_SYMBOLS_MAXSIZE)
> return -1;
> diff --git a/src/config.h b/src/config.h
> index 2a36c58..71f319a 100644
> --- a/src/config.h
> +++ b/src/config.h
> @@ -84,6 +84,7 @@ struct lt_config_shared {
>
> #define LT_SYMBOLS_MAXSIZE 200
> char symbols[LT_SYMBOLS_MAXSIZE];
> + char skipsymbols[LT_SYMBOLS_MAXSIZE];
>
> char flow_below[LT_SYMBOLS_MAXSIZE];
>
> @@ -186,6 +187,9 @@ struct lt_config_audit {
> char *symbols[LT_NAMES_MAX];
> int symbols_cnt;
>
> + char *skipsymbols[LT_NAMES_MAX];
> + int skipsymbols_cnt;
> +
> char *flow_below[LT_NAMES_MAX];
> int flow_below_cnt;
>
> --
>
