From 66223497d01883065ff63e29a6b17290eb1082b2 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 7 Jun 2018 12:29:52 +0200 Subject: [PATCH 1/3] sd-bus: also add destroy callbacks to sd_bus_track objects This augments previous work for this for sd_bus_slot objects, and adds the same concept to sd_bus_track objects, too. --- man/rules/meson.build | 5 +- man/sd_bus_slot_set_destroy_callback.xml | 60 +++++++++++++++++------- src/libsystemd/libsystemd.sym | 2 + src/libsystemd/sd-bus/bus-track.c | 30 ++++++++++-- src/systemd/sd-bus.h | 3 ++ 5 files changed, 77 insertions(+), 23 deletions(-) diff --git a/man/rules/meson.build b/man/rules/meson.build index efbd940fe0..765ff04b7d 100644 --- a/man/rules/meson.build +++ b/man/rules/meson.build @@ -233,7 +233,10 @@ manpages = [ ['sd_bus_set_watch_bind', '3', ['sd_bus_get_watch_bind'], ''], ['sd_bus_slot_set_destroy_callback', '3', - ['sd_bus_slot_get_destroy_callback'], + ['sd_bus_destroy_t', + 'sd_bus_slot_get_destroy_callback', + 'sd_bus_track_get_destroy_callback', + 'sd_bus_track_set_destroy_callback'], ''], ['sd_bus_slot_set_floating', '3', ['sd_bus_slot_get_floating'], ''], ['sd_bus_track_add_name', diff --git a/man/sd_bus_slot_set_destroy_callback.xml b/man/sd_bus_slot_set_destroy_callback.xml index 6334444f9a..a54b7e2d61 100644 --- a/man/sd_bus_slot_set_destroy_callback.xml +++ b/man/sd_bus_slot_set_destroy_callback.xml @@ -20,6 +20,9 @@ sd_bus_slot_set_destroy_callback sd_bus_slot_get_destroy_callback + sd_bus_track_set_destroy_callback + sd_bus_track_get_destroy_callback + sd_bus_destroy_t Define the callback function for resource cleanup. @@ -44,35 +47,54 @@ sd_bus_slot *slot sd_bus_destroy_t *callback + + + int sd_bus_track_set_destroy_callback + sd_bus_track *track + sd_bus_destroy_t callback + + + + int sd_bus_track_get_destroy_callback + sd_bus_track *track + sd_bus_destroy_t *callback + Description - sd_bus_slot_set_destroy_callback() sets - callback as the callback function to be called right before the bus slot - object slot is deallocated. The userdata pointer - from the slot object will be passed as the userdata parameter. This - pointer can be set specified as an argument to the constuctor functions, see - sd_bus_add_match3, - or directly, see - sd_bus_set_userdata3. - This callback function is called even if userdata is - NULL. + sd_bus_slot_set_destroy_callback() sets callback as the callback + function to be called right before the bus slot object slot is deallocated. The + userdata pointer from the slot object will be passed as the userdata + parameter. This pointer can be set by an argument to the constructor functions, see + sd_bus_add_match3, or directly, + see sd_bus_slot_set_userdata3. + This callback function is called even if userdata is NULL. Note that + this callback is invoked at a time where the bus slot object itself is already invalidated, and executing + operations or taking new references to the bus slot object is not permissible. sd_bus_slot_get_destroy_callback() returns the current callback for slot in the callback parameter. + + sd_bus_track_set_destroy_callback() and + sd_bus_track_get_destroy_callback provide equivalent functionality for the + userdata pointer associated with bus peer tracking objects. For details about bus peer + tracking objects, see + sd_bus_track_new3. Return Value - On success, sd_bus_slot_set_destroy_callback() returns 0 or a - positive integer. On failure, it returns a negative errno-style error code. + On success, sd_bus_slot_set_destroy_callback() and + sd_bus_track_set_destroy_callback() return 0 or a positive integer. On failure, they return a + negative errno-style error code. - sd_bus_slot_get_destroy_callback() returns 1 if the destroy callback - function is set, 0 if not. On failure, it returns a negative errno-style error code. + sd_bus_slot_get_destroy_callback() and + sd_bus_track_get_destroy_callback return positive if the destroy callback function is set, 0 + if not. On failure, they return a negative errno-style error code. @@ -84,8 +106,8 @@ -EINVAL - The slot parameter is NULL. - + The slot or track parameter is + NULL. @@ -98,7 +120,11 @@ systemd1, sd-bus3, - sd_bus_slot_set_floating3 + sd_bus_slot_set_floating3, + sd_bus_add_match3, + sd_bus_track_new3, + sd_bus_slot_set_userdata3, + sd_bus_track_set_userdata3 diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym index dc9c2d241a..7907bfb5df 100644 --- a/src/libsystemd/libsystemd.sym +++ b/src/libsystemd/libsystemd.sym @@ -565,6 +565,8 @@ global: sd_bus_slot_set_floating; sd_bus_slot_get_destroy_callback; sd_bus_slot_set_destroy_callback; + sd_bus_track_get_destroy_callback; + sd_bus_track_set_destroy_callback; sd_event_add_inotify; sd_event_source_get_inotify_mask; } LIBSYSTEMD_238; diff --git a/src/libsystemd/sd-bus/bus-track.c b/src/libsystemd/sd-bus/bus-track.c index 168c6c5ac7..1819eaffd4 100644 --- a/src/libsystemd/sd-bus/bus-track.c +++ b/src/libsystemd/sd-bus/bus-track.c @@ -31,6 +31,7 @@ struct sd_bus_track { bool in_queue:1; /* In bus->track_queue? */ bool modified:1; bool recursive:1; + sd_bus_destroy_t destroy_callback; LIST_FIELDS(sd_bus_track, tracks); }; @@ -164,18 +165,21 @@ _public_ sd_bus_track* sd_bus_track_unref(sd_bus_track *track) { return NULL; assert(track->n_ref > 0); + track->n_ref--; - if (track->n_ref > 1) { - track->n_ref--; + if (track->n_ref > 0) return NULL; - } if (track->in_list) LIST_REMOVE(tracks, track->bus->tracks, track); bus_track_remove_from_queue(track); - hashmap_free_with_destructor(track->names, track_item_free); - sd_bus_unref(track->bus); + track->names = hashmap_free_with_destructor(track->names, track_item_free); + track->bus = sd_bus_unref(track->bus); + + if (track->destroy_callback) + track->destroy_callback(track->userdata); + return mfree(track); } @@ -439,6 +443,22 @@ _public_ void *sd_bus_track_set_userdata(sd_bus_track *track, void *userdata) { return ret; } +_public_ int sd_bus_track_set_destroy_callback(sd_bus_track *track, sd_bus_destroy_t callback) { + assert_return(track, -EINVAL); + + track->destroy_callback = callback; + return 0; +} + +_public_ int sd_bus_track_get_destroy_callback(sd_bus_track *track, sd_bus_destroy_t *ret) { + assert_return(track, -EINVAL); + + if (ret) + *ret = track->destroy_callback; + + return !!track->destroy_callback; +} + _public_ int sd_bus_track_set_recursive(sd_bus_track *track, int b) { assert_return(track, -EINVAL); diff --git a/src/systemd/sd-bus.h b/src/systemd/sd-bus.h index b2394763c1..a1b1570663 100644 --- a/src/systemd/sd-bus.h +++ b/src/systemd/sd-bus.h @@ -485,6 +485,9 @@ const char* sd_bus_track_contains(sd_bus_track *track, const char *name); const char* sd_bus_track_first(sd_bus_track *track); const char* sd_bus_track_next(sd_bus_track *track); +int sd_bus_track_set_destroy_callback(sd_bus_track *s, sd_bus_destroy_t callback); +int sd_bus_track_get_destroy_callback(sd_bus_track *s, sd_bus_destroy_t *ret); + /* Define helpers so that __attribute__((cleanup(sd_bus_unrefp))) and similar may be used. */ _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus, sd_bus_unref); _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_bus, sd_bus_flush_close_unref); From 15723a1db086a98ec2ccfa8e6134c5b614bf4dce Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 7 Jun 2018 12:40:35 +0200 Subject: [PATCH 2/3] sd-event: add destroy callback logic to sd-event too This adds what has been added to sd_bus_slot and sd_bus_track to sd_event too. --- man/rules/meson.build | 4 + man/sd_event_source_set_destroy_callback.xml | 112 +++++++++++++++++++ src/libsystemd/libsystemd.sym | 2 + src/libsystemd/sd-event/sd-event.c | 23 +++- src/systemd/sd-event.h | 3 + 5 files changed, 143 insertions(+), 1 deletion(-) create mode 100644 man/sd_event_source_set_destroy_callback.xml diff --git a/man/rules/meson.build b/man/rules/meson.build index 765ff04b7d..68b7453a11 100644 --- a/man/rules/meson.build +++ b/man/rules/meson.build @@ -317,6 +317,10 @@ manpages = [ '3', ['sd_event_source_get_description'], ''], + ['sd_event_source_set_destroy_callback', + '3', + ['sd_event_destroy_t', 'sd_event_source_get_destroy_callback'], + ''], ['sd_event_source_set_enabled', '3', ['SD_EVENT_OFF', diff --git a/man/sd_event_source_set_destroy_callback.xml b/man/sd_event_source_set_destroy_callback.xml new file mode 100644 index 0000000000..34f7652c86 --- /dev/null +++ b/man/sd_event_source_set_destroy_callback.xml @@ -0,0 +1,112 @@ + + + + + + + + + sd_event_source_set_destroy_callback + systemd + + + + sd_event_source_set_destroy_callback + 3 + + + + sd_event_source_set_destroy_callback + sd_event_source_get_destroy_callback + sd_event_destroy_t + + Define the callback function for resource cleanup. + + + + + #include <systemd/sd-event.h> + + + typedef int (*sd_event_destroy_t) + void *userdata + + + + int sd_event_source_set_destroy_callback + sd_event_source *source + sd_event_destroy_t callback + + + + int sd_event_source_get_destroy_callback + sd_event_source *source + sd_event_destroy_t *callback + + + + + + + Description + + sd_event_source_set_destroy_callback() sets callback as the + callback function to be called right before the event source object source is + deallocated. The userdata pointer from the event source object will be passed as the + userdata parameter. This pointer can be set by an argument to the constructor functions, see + sd_event_add_io3, or directly, + see + sd_event_source_set_userdata3. + This callback function is called even if userdata is NULL. Note that + this callback is invoked at a time where the event source object itself is already invalidated, and executing + operations or taking new references to the event source object is not permissible. + + sd_event_source_get_destroy_callback() returns the current callback + for source in the callback parameter. + + + + Return Value + + On success, sd_event_source_set_destroy_callback() returns 0 or a positive integer. On + failure, it returns a negative errno-style error code. + + sd_event_source_get_destroy_callback() returns positive if the destroy callback function + is set, 0 if not. On failure, returns a negative errno-style error code. + + + + Errors + + Returned errors may indicate the following problems: + + + + -EINVAL + + The source parameter is NULL. + + + + + + + + See Also + + + systemd1, + sd-event3, + sd_event_add_io3, + sd_event_add_time3, + sd_event_add_signal3, + sd_event_add_child3, + sd_event_add_inotify3, + sd_event_add_defer3, + sd_event_source_set_userdata3 + + + + diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym index 7907bfb5df..270fe37e9f 100644 --- a/src/libsystemd/libsystemd.sym +++ b/src/libsystemd/libsystemd.sym @@ -569,4 +569,6 @@ global: sd_bus_track_set_destroy_callback; sd_event_add_inotify; sd_event_source_get_inotify_mask; + sd_event_source_set_destroy_callback; + sd_event_source_get_destroy_callback; } LIBSYSTEMD_238; diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c index 1b983dbe37..196b90d59b 100644 --- a/src/libsystemd/sd-event/sd-event.c +++ b/src/libsystemd/sd-event/sd-event.c @@ -106,6 +106,8 @@ struct sd_event_source { uint64_t pending_iteration; uint64_t prepare_iteration; + sd_event_destroy_t destroy_callback; + LIST_FIELDS(sd_event_source, sources); union { @@ -1016,7 +1018,10 @@ static void source_free(sd_event_source *s) { source_disconnect(s); if (s->type == SOURCE_IO && s->io.owned) - safe_close(s->io.fd); + s->io.fd = safe_close(s->io.fd); + + if (s->destroy_callback) + s->destroy_callback(s->userdata); free(s->description); free(s); @@ -3775,3 +3780,19 @@ _public_ int sd_event_get_iteration(sd_event *e, uint64_t *ret) { *ret = e->iteration; return 0; } + +_public_ int sd_event_source_set_destroy_callback(sd_event_source *s, sd_event_destroy_t callback) { + assert_return(s, -EINVAL); + + s->destroy_callback = callback; + return 0; +} + +_public_ int sd_event_source_get_destroy_callback(sd_event_source *s, sd_event_destroy_t *ret) { + assert_return(s, -EINVAL); + + if (ret) + *ret = s->destroy_callback; + + return !!s->destroy_callback; +} diff --git a/src/systemd/sd-event.h b/src/systemd/sd-event.h index 28939ca550..fc5a75b6b6 100644 --- a/src/systemd/sd-event.h +++ b/src/systemd/sd-event.h @@ -80,6 +80,7 @@ typedef int (*sd_event_child_handler_t)(sd_event_source *s, const siginfo_t *si, typedef void* sd_event_child_handler_t; #endif typedef int (*sd_event_inotify_handler_t)(sd_event_source *s, const struct inotify_event *event, void *userdata); +typedef void (*sd_event_destroy_t)(void *userdata); int sd_event_default(sd_event **e); @@ -143,6 +144,8 @@ int sd_event_source_get_time_clock(sd_event_source *s, clockid_t *clock); int sd_event_source_get_signal(sd_event_source *s); int sd_event_source_get_child_pid(sd_event_source *s, pid_t *pid); int sd_event_source_get_inotify_mask(sd_event_source *s, uint32_t *ret); +int sd_event_source_set_destroy_callback(sd_event_source *s, sd_event_destroy_t callback); +int sd_event_source_get_destroy_callback(sd_event_source *s, sd_event_destroy_t *ret); /* Define helpers so that __attribute__((cleanup(sd_event_unrefp))) and similar may be used. */ _SD_DEFINE_POINTER_CLEANUP_FUNC(sd_event, sd_event_unref); From 90b1fa59cfee2d2c469de89e71b6366ebd28a1f3 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 7 Jun 2018 13:07:52 +0200 Subject: [PATCH 3/3] sd-event: document sd_event_source_set_io_fd_own() With this we have 100% of the sd-event symbols documented again. Yay! --- man/rules/meson.build | 4 +++- man/sd_event_add_io.xml | 24 ++++++++++++++++++++++++ 2 files changed, 27 insertions(+), 1 deletion(-) diff --git a/man/rules/meson.build b/man/rules/meson.build index 68b7453a11..04f03c6786 100644 --- a/man/rules/meson.build +++ b/man/rules/meson.build @@ -280,9 +280,11 @@ manpages = [ 'sd_event_source', 'sd_event_source_get_io_events', 'sd_event_source_get_io_fd', + 'sd_event_source_get_io_fd_own', 'sd_event_source_get_io_revents', 'sd_event_source_set_io_events', - 'sd_event_source_set_io_fd'], + 'sd_event_source_set_io_fd', + 'sd_event_source_set_io_fd_own'], ''], ['sd_event_add_signal', '3', diff --git a/man/sd_event_add_io.xml b/man/sd_event_add_io.xml index d5ef462e53..bd513a7814 100644 --- a/man/sd_event_add_io.xml +++ b/man/sd_event_add_io.xml @@ -38,6 +38,8 @@ sd_event_source_get_io_revents sd_event_source_get_io_fd sd_event_source_set_io_fd + sd_event_source_get_io_fd_own + sd_event_source_set_io_fd_own sd_event_source sd_event_io_handler_t @@ -97,6 +99,17 @@ int fd + + int sd_event_source_get_io_fd_own + sd_event_source *source + + + + int sd_event_source_set_io_fd_own + sd_event_source *source + int b + + @@ -212,6 +225,17 @@ changes the UNIX file descriptor of an I/O event source created previously with sd_event_add_io(). It takes the event source object and the new file descriptor. + + sd_event_source_set_io_fd_own() controls whether the file descriptor of the event source + shall be closed automatically when the event source is freed, i.e. whether it shall be considered 'owned' by the + event source object. By default it is not closed automatically, and the application has to do this on its own. The + b parameter is a boolean parameter: if zero, the file descriptor is not closed automatically + when the event source is freed, otherwise it is closed. + + sd_event_source_get_io_fd_own() may be used to query the current setting of the file + descriptor ownership boolean flag as set with sd_event_source_set_io_fd_own(). It returns + positive if the file descriptor is closed automatically when the event source is destroyed, zero if not, and + negative on error.