diff options
Diffstat (limited to 'src/core/dbus-client-track.c')
| -rw-r--r-- | src/core/dbus-client-track.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/src/core/dbus-client-track.c b/src/core/dbus-client-track.c new file mode 100644 index 0000000000..ce514b577c --- /dev/null +++ b/src/core/dbus-client-track.c @@ -0,0 +1,250 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2013 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include "dbus-client-track.h" + +static unsigned tracked_client_hash(const void *a) { + const BusTrackedClient *x = a; + + return string_hash_func(x->name) ^ PTR_TO_UINT(x->bus); +} + +static int tracked_client_compare(const void *a, const void *b) { + const BusTrackedClient *x = a, *y = b; + int r; + + r = strcmp(x->name, y->name); + if (r != 0) + return r; + + if (x->bus < y->bus) + return -1; + if (x->bus > y->bus) + return 1; + + return 0; +} + +static int on_name_owner_changed(sd_bus *bus, sd_bus_message *message, void *userdata) { + BusTrackedClient *c = userdata; + const char *name, *old, *new; + int r; + + assert(bus); + assert(message); + + r = sd_bus_message_read(message, "sss", &name, &old, &new); + if (r < 0) { + log_debug("Failed to parse NameOwnerChanged message."); + return 0; + } + + bus_client_untrack(c->set, bus, name); + return 0; +} + +static char *build_match(const char *name) { + + return strjoin("type='signal'," + "sender='org.freedesktop.DBus'," + "path='/org/freedesktop/DBus'," + "interface='org.freedesktop.DBus'," + "member='NameOwnerChanged'," + "arg0='", name, "'", NULL); +} + +int bus_client_track(Set **s, sd_bus *bus, const char *name) { + BusTrackedClient *c, *found; + size_t l; + int r; + + assert(s); + assert(bus); + + r = set_ensure_allocated(s, tracked_client_hash, tracked_client_compare); + if (r < 0) + return r; + + name = strempty(name); + + l = strlen(name); + + c = alloca(offsetof(BusTrackedClient, name) + l + 1); + c->set = *s; + c->bus = bus; + strcpy(c->name, name); + + found = set_get(*s, c); + if (found) + return 0; + + c = memdup(c, offsetof(BusTrackedClient, name) + l + 1); + if (!c) + return -ENOMEM; + + r = set_put(*s, c); + if (r < 0) { + free(c); + return r; + } + + if (!isempty(name)) { + _cleanup_free_ char *match = NULL; + + match = build_match(name); + if (!match) { + set_remove(*s, c); + free(c); + return -ENOMEM; + } + + r = sd_bus_add_match(bus, match, on_name_owner_changed, c); + if (r < 0) { + set_remove(*s, c); + free(c); + return r; + } + } + + sd_bus_ref(c->bus); + return 1; +} + +static void bus_client_free_one(Set *s, BusTrackedClient *c) { + assert(s); + assert(c); + + if (!isempty(c->name)) { + _cleanup_free_ char *match = NULL; + + match = build_match(c->name); + if (match) + sd_bus_remove_match(c->bus, match, on_name_owner_changed, c); + } + + sd_bus_unref(c->bus); + set_remove(s, c); + free(c); +} + +int bus_client_untrack(Set *s, sd_bus *bus, const char *name) { + BusTrackedClient *c, *found; + size_t l; + + assert(bus); + assert(s); + assert(name); + + name = strempty(name); + + l = strlen(name); + + c = alloca(offsetof(BusTrackedClient, name) + l + 1); + c->bus = bus; + strcpy(c->name, name); + + found = set_get(s, c); + if (!found) + return 0; + + bus_client_free_one(s, found); + return 1; +} + +void bus_client_track_free(Set *s) { + BusTrackedClient *c; + + while ((c = set_first(s))) + bus_client_free_one(s, c); + + set_free(s); +} + +int bus_client_untrack_bus(Set *s, sd_bus *bus) { + BusTrackedClient *c; + Iterator i; + int r = 0; + + SET_FOREACH(c, s, i) + if (c->bus == bus) { + bus_client_free_one(s, c); + r++; + } + + return r; +} + +void bus_client_track_serialize(Manager *m, FILE *f, Set *s) { + BusTrackedClient *c; + Iterator i; + + assert(m); + assert(f); + + SET_FOREACH(c, s, i) { + if (c->bus == m->api_bus) + fprintf(f, "subscribed=%s", isempty(c->name) ? "*" : c->name); + else + fprintf(f, "subscribed=%p %s", c->bus, isempty(c->name) ? "*" : c->name); + } +} + +int bus_client_track_deserialize_item(Manager *m, Set **s, const char *line) { + const char *e, *q, *name; + sd_bus *bus; + void *p; + int r; + + e = startswith(line, "subscribed="); + if (!e) + return 0; + + q = strpbrk(e, WHITESPACE); + if (!q) { + if (m->api_bus) { + bus = m->api_bus; + name = e; + goto finish; + } + + return 1; + } + + if (sscanf(e, "%p", &p) != 1) { + log_debug("Failed to parse subscription pointer."); + return -EINVAL; + } + + bus = set_get(m->private_buses, p); + if (!bus) + return 1; + + name = q + strspn(q, WHITESPACE); + +finish: + r = bus_client_track(s, bus, streq(name, "*") ? NULL : name); + if (r < 0) { + log_debug("Failed to deserialize client subscription: %s", strerror(-r)); + return r; + } + + return 1; +} |