diff options
| -rw-r--r-- | doc/README.tapping | 14 | ||||
| -rw-r--r-- | epan/tap.c | 11 | ||||
| -rw-r--r-- | ui/cli/tap-follow.c | 2 |
3 files changed, 19 insertions, 8 deletions
diff --git a/doc/README.tapping b/doc/README.tapping index 5c62a475f0..769c5dc4b4 100644 --- a/doc/README.tapping +++ b/doc/README.tapping @@ -57,7 +57,7 @@ TAP LISTENER ============ (see tap-rpcstat.c as an example) Interfacing your application is not that much harder either. -Only 3 callbacks and two functions. +Only 4 callbacks and two functions. The two functions to start or stop tapping are @@ -66,7 +66,8 @@ register_tap_listener(const char *tapname, void *tapdata, const char *fstring, guint flags, void (*reset)(void *tapdata), gboolean (*packet)(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const void *data), - void (*draw)(void *tapdata)); + void (*draw)(void *tapdata), + void (*finish)(void *tapdata)); remove_tap_listener(void *tapdata); @@ -156,12 +157,15 @@ from a separate thread up to once every 2-3 seconds. On other ports it might only be called once when the capture is finished or the file has been [re]read completely. +void (*finish)(void *tapdata) +This callback is called when your listener is removed. -So, create three callbacks: +So, create four callbacks: 1, reset to reset the state variables in the structure passed to it. 2, packet to update these state variables. 3, draw to take these state variables and draw them on the screen. +4, finish to free all state variables. then just make Wireshark call register_tap_listener() when you want to tap and call remove_tap_listener() when you are finished. @@ -209,7 +213,7 @@ TIPS ==== Of course, there is nothing that forces you to make (*draw) draw stuff on the screen. -You can hand register_tap_listener() NULL for both (*draw) and (*reset) +You can hand register_tap_listener() NULL for (*draw), (*reset) and (*finish) (well also for (*packet) but that would be a very boring extension). Perhaps you want an extension that will execute a certain command @@ -221,7 +225,7 @@ Well, try this : return FALSE; } - register_tap_listener("tcp", struct, "tcp.port==57", NULL, packet, NULL); + register_tap_listener("tcp", struct, "tcp.port==57", NULL, packet, NULL, NULL); Let struct contain an email address? Then you have something simple that will make Wireshark send an email diff --git a/epan/tap.c b/epan/tap.c index 5049d2ec3d..36de269192 100644 --- a/epan/tap.c +++ b/epan/tap.c @@ -449,6 +449,15 @@ find_tap_id(const char *name) static void free_tap_listener(tap_listener_t *tl) { + /* The free_tap_listener is called in the error path of + * register_tap_listener (when the dfilter fails to be registered) + * and the finish callback is set after that. + * If this is changed make sure the finish callback is not called + * twice to prevent double-free errors. + */ + if (tl->finish) { + tl->finish(tl->tapdata); + } dfilter_free(tl->code); g_free(tl->fstring); g_free(tl); @@ -616,8 +625,6 @@ remove_tap_listener(void *tapdata) return; } } - if(tl->finish) - tl->finish(tapdata); free_tap_listener(tl); } diff --git a/ui/cli/tap-follow.c b/ui/cli/tap-follow.c index 2c2fa74ce0..16238d8889 100644 --- a/ui/cli/tap-follow.c +++ b/ui/cli/tap-follow.c @@ -472,7 +472,7 @@ static void follow_stream(const char *opt_argp, void *userdata) } errp = register_tap_listener(get_follow_tap_string(follower), follow_info, follow_info->filter_out_filter, 0, - NULL, get_follow_tap_handler(follower), follow_draw, NULL); + NULL, get_follow_tap_handler(follower), follow_draw, (tap_finish_cb)follow_free); if (errp != NULL) { |