]> git.ipfire.org Git - thirdparty/systemd.git/blobdiff - src/libsystemd/sd-bus/sd-bus.c
bus: add comment to explain assert
[thirdparty/systemd.git] / src / libsystemd / sd-bus / sd-bus.c
index e5966cfe2ef67a4b536b9b993023d5f70ca0f243..7787caaa4f184b9bf14b322c4bcf452d545b147a 100644 (file)
@@ -1,9 +1,4 @@
 /* SPDX-License-Identifier: LGPL-2.1+ */
-/***
-  This file is part of systemd.
-
-  Copyright 2013 Lennart Poettering
-***/
 
 #include <endian.h>
 #include <netdb.h>
@@ -163,7 +158,7 @@ static void bus_reset_queues(sd_bus *b) {
         b->wqueue_allocated = 0;
 }
 
-static void bus_free(sd_bus *b) {
+static sd_bus* bus_free(sd_bus *b) {
         sd_bus_slot *s;
 
         assert(b);
@@ -228,56 +223,47 @@ static void bus_free(sd_bus *b) {
 
         assert_se(pthread_mutex_destroy(&b->memfd_cache_mutex) == 0);
 
-        free(b);
+        return mfree(b);
 }
 
+DEFINE_TRIVIAL_CLEANUP_FUNC(sd_bus*, bus_free);
+
 _public_ int sd_bus_new(sd_bus **ret) {
-        sd_bus *r;
+        _cleanup_free_ sd_bus *b = NULL;
 
         assert_return(ret, -EINVAL);
 
-        r = new0(sd_bus, 1);
-        if (!r)
+        b = new0(sd_bus, 1);
+        if (!b)
                 return -ENOMEM;
 
-        r->n_ref = REFCNT_INIT;
-        r->input_fd = r->output_fd = -1;
-        r->inotify_fd = -1;
-        r->message_version = 1;
-        r->creds_mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_UNIQUE_NAME;
-        r->accept_fd = true;
-        r->original_pid = getpid_cached();
-        r->n_groups = (size_t) -1;
-
-        assert_se(pthread_mutex_init(&r->memfd_cache_mutex, NULL) == 0);
-
-        /* We guarantee that wqueue always has space for at least one
-         * entry */
-        if (!GREEDY_REALLOC(r->wqueue, r->wqueue_allocated, 1)) {
-                free(r);
+        b->n_ref = REFCNT_INIT;
+        b->input_fd = b->output_fd = -1;
+        b->inotify_fd = -1;
+        b->message_version = 1;
+        b->creds_mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_UNIQUE_NAME;
+        b->accept_fd = true;
+        b->original_pid = getpid_cached();
+        b->n_groups = (size_t) -1;
+
+        assert_se(pthread_mutex_init(&b->memfd_cache_mutex, NULL) == 0);
+
+        /* We guarantee that wqueue always has space for at least one entry */
+        if (!GREEDY_REALLOC(b->wqueue, b->wqueue_allocated, 1))
                 return -ENOMEM;
-        }
 
-        *ret = r;
+        *ret = TAKE_PTR(b);
         return 0;
 }
 
 _public_ int sd_bus_set_address(sd_bus *bus, const char *address) {
-        char *a;
-
         assert_return(bus, -EINVAL);
         assert_return(bus = bus_resolve(bus), -ENOPKG);
         assert_return(bus->state == BUS_UNSET, -EPERM);
         assert_return(address, -EINVAL);
         assert_return(!bus_pid_changed(bus), -ECHILD);
 
-        a = strdup(address);
-        if (!a)
-                return -ENOMEM;
-
-        free_and_replace(bus->address, a);
-
-        return 0;
+        return free_and_strdup(&bus->address, address);
 }
 
 _public_ int sd_bus_set_fd(sd_bus *bus, int input_fd, int output_fd) {
@@ -294,7 +280,8 @@ _public_ int sd_bus_set_fd(sd_bus *bus, int input_fd, int output_fd) {
 }
 
 _public_ int sd_bus_set_exec(sd_bus *bus, const char *path, char *const argv[]) {
-        char *p, **a;
+        _cleanup_strv_free_ char **a = NULL;
+        int r;
 
         assert_return(bus, -EINVAL);
         assert_return(bus = bus_resolve(bus), -ENOPKG);
@@ -303,22 +290,15 @@ _public_ int sd_bus_set_exec(sd_bus *bus, const char *path, char *const argv[])
         assert_return(!strv_isempty(argv), -EINVAL);
         assert_return(!bus_pid_changed(bus), -ECHILD);
 
-        p = strdup(path);
-        if (!p)
-                return -ENOMEM;
-
         a = strv_copy(argv);
-        if (!a) {
-                free(p);
+        if (!a)
                 return -ENOMEM;
-        }
-
-        free_and_replace(bus->exec_path, p);
 
-        strv_free(bus->exec_argv);
-        bus->exec_argv = a;
+        r = free_and_strdup(&bus->exec_path, path);
+        if (r < 0)
+                return r;
 
-        return 0;
+        return strv_free_and_replace(bus->exec_argv, a);
 }
 
 _public_ int sd_bus_set_bus_client(sd_bus *bus, int b) {
@@ -542,7 +522,6 @@ void bus_set_state(sd_bus *bus, enum bus_state state) {
 
 static int hello_callback(sd_bus_message *reply, void *userdata, sd_bus_error *error) {
         const char *s;
-        char *t;
         sd_bus *bus;
         int r;
 
@@ -562,11 +541,9 @@ static int hello_callback(sd_bus_message *reply, void *userdata, sd_bus_error *e
         if (!service_name_is_valid(s) || s[0] != ':')
                 return -EBADMSG;
 
-        t = strdup(s);
-        if (!t)
-                return -ENOMEM;
-
-        free_and_replace(bus->unique_name, t);
+        r = free_and_strdup(&bus->unique_name, s);
+        if (r < 0)
+                return r;
 
         if (bus->state == BUS_HELLO) {
                 bus_set_state(bus, BUS_RUNNING);
@@ -1208,7 +1185,7 @@ _public_ int sd_bus_start(sd_bus *bus) {
 
 _public_ int sd_bus_open_with_description(sd_bus **ret, const char *description) {
         const char *e;
-        sd_bus *b;
+        _cleanup_(bus_freep) sd_bus *b = NULL;
         int r;
 
         assert_return(ret, -EINVAL);
@@ -1239,7 +1216,7 @@ _public_ int sd_bus_open_with_description(sd_bus **ret, const char *description)
 
         r = sd_bus_set_address(b, e);
         if (r < 0)
-                goto fail;
+                return r;
 
         b->bus_client = true;
 
@@ -1251,14 +1228,10 @@ _public_ int sd_bus_open_with_description(sd_bus **ret, const char *description)
 
         r = sd_bus_start(b);
         if (r < 0)
-                goto fail;
+                return r;
 
-        *ret = b;
+        *ret = TAKE_PTR(b);
         return 0;
-
-fail:
-        bus_free(b);
-        return r;
 }
 
 _public_ int sd_bus_open(sd_bus **ret) {
@@ -1277,7 +1250,7 @@ int bus_set_address_system(sd_bus *b) {
 }
 
 _public_ int sd_bus_open_system_with_description(sd_bus **ret, const char *description) {
-        sd_bus *b;
+        _cleanup_(bus_freep) sd_bus *b = NULL;
         int r;
 
         assert_return(ret, -EINVAL);
@@ -1289,12 +1262,12 @@ _public_ int sd_bus_open_system_with_description(sd_bus **ret, const char *descr
         if (description) {
                 r = sd_bus_set_description(b, description);
                 if (r < 0)
-                        goto fail;
+                        return r;
         }
 
         r = bus_set_address_system(b);
         if (r < 0)
-                goto fail;
+                return r;
 
         b->bus_client = true;
         b->is_system = true;
@@ -1307,14 +1280,10 @@ _public_ int sd_bus_open_system_with_description(sd_bus **ret, const char *descr
 
         r = sd_bus_start(b);
         if (r < 0)
-                goto fail;
+                return r;
 
-        *ret = b;
+        *ret = TAKE_PTR(b);
         return 0;
-
-fail:
-        bus_free(b);
-        return r;
 }
 
 _public_ int sd_bus_open_system(sd_bus **ret) {
@@ -1348,7 +1317,7 @@ int bus_set_address_user(sd_bus *b) {
 }
 
 _public_ int sd_bus_open_user_with_description(sd_bus **ret, const char *description) {
-        sd_bus *b;
+        _cleanup_(bus_freep) sd_bus *b = NULL;
         int r;
 
         assert_return(ret, -EINVAL);
@@ -1360,12 +1329,12 @@ _public_ int sd_bus_open_user_with_description(sd_bus **ret, const char *descrip
         if (description) {
                 r = sd_bus_set_description(b, description);
                 if (r < 0)
-                        goto fail;
+                        return r;
         }
 
         r = bus_set_address_user(b);
         if (r < 0)
-                goto fail;
+                return r;
 
         b->bus_client = true;
         b->is_user = true;
@@ -1377,14 +1346,10 @@ _public_ int sd_bus_open_user_with_description(sd_bus **ret, const char *descrip
 
         r = sd_bus_start(b);
         if (r < 0)
-                goto fail;
+                return r;
 
-        *ret = b;
+        *ret = TAKE_PTR(b);
         return 0;
-
-fail:
-        bus_free(b);
-        return r;
 }
 
 _public_ int sd_bus_open_user(sd_bus **ret) {
@@ -1405,7 +1370,7 @@ int bus_set_address_system_remote(sd_bus *b, const char *host) {
 
                 /* Let's make sure this is not a port of some kind,
                  * and is a valid machine name. */
-                if (!in_charset(m, "0123456789") && machine_name_is_valid(m)) {
+                if (!in_charset(m, DIGITS) && machine_name_is_valid(m)) {
                         char *t;
 
                         /* Cut out the host part */
@@ -1428,41 +1393,35 @@ int bus_set_address_system_remote(sd_bus *b, const char *host) {
         if (!a)
                 return -ENOMEM;
 
-        free_and_replace(b->address, a);
-
-        return 0;
- }
+        return free_and_replace(b->address, a);
+}
 
 _public_ int sd_bus_open_system_remote(sd_bus **ret, const char *host) {
-        sd_bus *bus;
+        _cleanup_(bus_freep) sd_bus *b = NULL;
         int r;
 
         assert_return(host, -EINVAL);
         assert_return(ret, -EINVAL);
 
-        r = sd_bus_new(&bus);
+        r = sd_bus_new(&b);
         if (r < 0)
                 return r;
 
-        r = bus_set_address_system_remote(bus, host);
+        r = bus_set_address_system_remote(b, host);
         if (r < 0)
-                goto fail;
+                return r;
 
-        bus->bus_client = true;
-        bus->trusted = false;
-        bus->is_system = true;
-        bus->is_local = false;
+        b->bus_client = true;
+        b->trusted = false;
+        b->is_system = true;
+        b->is_local = false;
 
-        r = sd_bus_start(bus);
+        r = sd_bus_start(b);
         if (r < 0)
-                goto fail;
+                return r;
 
-        *ret = bus;
+        *ret = TAKE_PTR(b);
         return 0;
-
-fail:
-        bus_free(bus);
-        return r;
 }
 
 int bus_set_address_system_machine(sd_bus *b, const char *machine) {
@@ -1480,46 +1439,39 @@ int bus_set_address_system_machine(sd_bus *b, const char *machine) {
         if (!a)
                 return -ENOMEM;
 
-        free_and_replace(b->address, a);
-
-        return 0;
+        return free_and_replace(b->address, a);
 }
 
 _public_ int sd_bus_open_system_machine(sd_bus **ret, const char *machine) {
-        sd_bus *bus;
+        _cleanup_(bus_freep) sd_bus *b = NULL;
         int r;
 
         assert_return(machine, -EINVAL);
         assert_return(ret, -EINVAL);
         assert_return(machine_name_is_valid(machine), -EINVAL);
 
-        r = sd_bus_new(&bus);
+        r = sd_bus_new(&b);
         if (r < 0)
                 return r;
 
-        r = bus_set_address_system_machine(bus, machine);
+        r = bus_set_address_system_machine(b, machine);
         if (r < 0)
-                goto fail;
+                return r;
 
-        bus->bus_client = true;
-        bus->trusted = false;
-        bus->is_system = true;
-        bus->is_local = false;
+        b->bus_client = true;
+        b->trusted = false;
+        b->is_system = true;
+        b->is_local = false;
 
-        r = sd_bus_start(bus);
+        r = sd_bus_start(b);
         if (r < 0)
-                goto fail;
+                return r;
 
-        *ret = bus;
+        *ret = TAKE_PTR(b);
         return 0;
-
-fail:
-        bus_free(bus);
-        return r;
 }
 
 _public_ void sd_bus_close(sd_bus *bus) {
-
         if (!bus)
                 return;
         if (bus->state == BUS_CLOSED)
@@ -1543,7 +1495,6 @@ _public_ void sd_bus_close(sd_bus *bus) {
 }
 
 _public_ sd_bus* sd_bus_flush_close_unref(sd_bus *bus) {
-
         if (!bus)
                 return NULL;
 
@@ -1566,7 +1517,6 @@ void bus_enter_closing(sd_bus *bus) {
 }
 
 _public_ sd_bus *sd_bus_ref(sd_bus *bus) {
-
         if (!bus)
                 return NULL;
 
@@ -1585,12 +1535,10 @@ _public_ sd_bus *sd_bus_unref(sd_bus *bus) {
         if (i > 0)
                 return NULL;
 
-        bus_free(bus);
-        return NULL;
+        return bus_free(bus);
 }
 
 _public_ int sd_bus_is_open(sd_bus *bus) {
-
         assert_return(bus, -EINVAL);
         assert_return(bus = bus_resolve(bus), -ENOPKG);
         assert_return(!bus_pid_changed(bus), -ECHILD);
@@ -1661,8 +1609,11 @@ static int bus_seal_message(sd_bus *b, sd_bus_message *m, usec_t timeout) {
                 return 0;
         }
 
-        if (timeout == 0)
-                timeout = BUS_DEFAULT_TIMEOUT;
+        if (timeout == 0) {
+                r = sd_bus_get_method_call_timeout(b, &timeout);
+                if (r < 0)
+                        return r;
+        }
 
         if (!m->sender && b->patch_sender) {
                 r = sd_bus_message_set_sender(m, b->patch_sender);
@@ -2933,7 +2884,6 @@ finish:
 }
 
 static int bus_process_internal(sd_bus *bus, bool hint_priority, int64_t priority, sd_bus_message **ret) {
-        BUS_DONT_DESTROY(bus);
         int r;
 
         /* Returns 0 when we didn't do anything. This should cause the
@@ -2947,7 +2897,9 @@ static int bus_process_internal(sd_bus *bus, bool hint_priority, int64_t priorit
 
         /* We don't allow recursively invoking sd_bus_process(). */
         assert_return(!bus->current_message, -EBUSY);
-        assert(!bus->current_slot);
+        assert(!bus->current_slot); /* This should be NULL whenever bus->current_message is */
+
+        BUS_DONT_DESTROY(bus);
 
         switch (bus->state) {
 
@@ -3274,13 +3226,21 @@ static int bus_add_match_full(
                                 goto finish;
                         }
 
-                        if (asynchronous)
+                        if (asynchronous) {
                                 r = bus_add_match_internal_async(bus,
                                                                  &s->match_callback.install_slot,
                                                                  s->match_callback.match_string,
                                                                  add_match_callback,
                                                                  s);
-                        else
+
+                                if (r < 0)
+                                        return r;
+
+                                /* Make the slot of the match call floating now. We need the reference, but we don't
+                                 * want that this match pins the bus object, hence we first create it non-floating, but
+                                 * then make it floating. */
+                                r = sd_bus_slot_set_floating(s->match_callback.install_slot, true);
+                        } else
                                 r = bus_add_match_internal(bus, s->match_callback.match_string);
                         if (r < 0)
                                 goto finish;
@@ -3677,7 +3637,6 @@ _public_ int sd_bus_default_system(sd_bus **ret) {
         return bus_default(sd_bus_open_system, &default_system_bus, ret);
 }
 
-
 _public_ int sd_bus_default_user(sd_bus **ret) {
         return bus_default(sd_bus_open_user, &default_user_bus, ret);
 }
@@ -4118,3 +4077,36 @@ _public_ int sd_bus_get_n_queued_write(sd_bus *bus, uint64_t *ret) {
         *ret = bus->wqueue_size;
         return 0;
 }
+
+_public_ int sd_bus_set_method_call_timeout(sd_bus *bus, uint64_t usec) {
+        assert_return(bus, -EINVAL);
+        assert_return(bus = bus_resolve(bus), -ENOPKG);
+
+        bus->method_call_timeout = usec;
+        return 0;
+}
+
+_public_ int sd_bus_get_method_call_timeout(sd_bus *bus, uint64_t *ret) {
+        const char *e;
+        usec_t usec;
+
+        assert_return(bus, -EINVAL);
+        assert_return(bus = bus_resolve(bus), -ENOPKG);
+        assert_return(ret, -EINVAL);
+
+        if (bus->method_call_timeout != 0) {
+                *ret = bus->method_call_timeout;
+                return 0;
+        }
+
+        e = secure_getenv("SYSTEMD_BUS_TIMEOUT");
+        if (e && parse_sec(e, &usec) >= 0 && usec != 0) {
+                /* Save the parsed value to avoid multiple parsing. To change the timeout value,
+                 * use sd_bus_set_method_call_timeout() instead of setenv(). */
+                *ret = bus->method_call_timeout = usec;
+                return 0;
+        }
+
+        *ret = bus->method_call_timeout = BUS_DEFAULT_TIMEOUT;
+        return 0;
+}