From 3022d49ba2276eb5634d84a89a078aa3c357b70a Mon Sep 17 00:00:00 2001

From: Yu Watanabe <watanabe.yu+github@gmail.com>

Date: Fri, 13 Jul 2018 17:38:47 +0900

Subject: [PATCH] sd-bus: make BUS_DEFAULT_TIMEOUT configurable

This adds sd_bus_{get,set}_method_call_timeout().

If the timeout is not set or set to 0, then the timeout value is

parsed from $SYSTEMD_BUS_TIMEOUT= environment variable. If the

environment variable is not set, then built-in timeout is used.

(cherry picked from commit 385b2eb262a99373f09d01b7f5571dd71a14dc98)

Resolves: #2039461

---

 doc/ENVIRONMENT.md                   |  5 ++++

 src/libsystemd/libsystemd.sym        |  7 ++++-

 src/libsystemd/sd-bus/bus-internal.h |  9 ++++---

 src/libsystemd/sd-bus/bus-message.c  |  7 +++--

 src/libsystemd/sd-bus/sd-bus.c       | 40 ++++++++++++++++++++++++++--

 src/systemd/sd-bus.h                 |  3 +++

 6 files changed, 62 insertions(+), 9 deletions(-)

diff --git a/doc/ENVIRONMENT.md b/doc/ENVIRONMENT.md

index 8d7ce6ae2c..d1a79eaa4f 100644

--- a/doc/ENVIRONMENT.md

+++ b/doc/ENVIRONMENT.md

@@ -50,6 +50,11 @@ All tools:

   this only controls use of Unicode emoji glyphs, and has no effect on other

   Unicode glyphs.

+* `$SYSTEMD_BUS_TIMEOUT=SECS` — specifies the maximum time to wait for method call

+  completion. If no time unit is specified, assumes seconds. The usual other units

+  are understood, too (us, ms, s, min, h, d, w, month, y). If it is not set or set

+  to 0, then the built-in default is used.

+

 systemctl:

 * `$SYSTEMCTL_FORCE_BUS=1` — if set, do not connect to PID1's private D-Bus

diff --git a/src/libsystemd/libsystemd.sym b/src/libsystemd/libsystemd.sym

index f4a1426248..3b55fc6473 100644

--- a/src/libsystemd/libsystemd.sym

+++ b/src/libsystemd/libsystemd.sym

@@ -573,12 +573,17 @@ global:

         sd_event_source_disable_unref;

 } LIBSYSTEMD_238;

+LIBSYSTEMD_240 {

+        sd_bus_set_method_call_timeout;

+        sd_bus_get_method_call_timeout;

+} LIBSYSTEMD_239;

+

 LIBSYSTEMD_248 {

 global:

         sd_event_source_set_ratelimit;

         sd_event_source_get_ratelimit;

         sd_event_source_is_ratelimited;

-} LIBSYSTEMD_239;

+} LIBSYSTEMD_240;

 LIBSYSTEMD_250 {

 global:

diff --git a/src/libsystemd/sd-bus/bus-internal.h b/src/libsystemd/sd-bus/bus-internal.h

index 06bd7862cb..88415ae678 100644

--- a/src/libsystemd/sd-bus/bus-internal.h

+++ b/src/libsystemd/sd-bus/bus-internal.h

@@ -319,6 +319,9 @@ struct sd_bus {

         int *inotify_watches;

         size_t n_inotify_watches;

+

+        /* zero means use value specified by $SYSTEMD_BUS_TIMEOUT= environment variable or built-in default */

+        usec_t method_call_timeout;

 };

 /* For method calls we time-out at 25s, like in the D-Bus reference implementation */

@@ -340,8 +343,7 @@ struct sd_bus {

 #define BUS_CONTAINER_DEPTH 128

-/* Defined by the specification as maximum size of an array in

- * bytes */

+/* Defined by the specification as maximum size of an array in bytes */

 #define BUS_ARRAY_MAX_SIZE 67108864

 #define BUS_FDS_MAX 1024

@@ -392,8 +394,7 @@ void bus_close_io_fds(sd_bus *b);

              _slash = streq((prefix), "/") ? NULL : strrchr((prefix), '/'))

 /* If we are invoking callbacks of a bus object, ensure unreffing the

- * bus from the callback doesn't destroy the object we are working

- * on */

+ * bus from the callback doesn't destroy the object we are working on */

 #define BUS_DONT_DESTROY(bus) \

         _cleanup_(sd_bus_unrefp) _unused_ sd_bus *_dont_destroy_##bus = sd_bus_ref(bus)

diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c

index 7fe8929f82..3ffe559b8d 100644

--- a/src/libsystemd/sd-bus/bus-message.c

+++ b/src/libsystemd/sd-bus/bus-message.c

@@ -5882,8 +5882,11 @@ int bus_message_remarshal(sd_bus *bus, sd_bus_message **m) {

                 return r;

         timeout = (*m)->timeout;

-        if (timeout == 0 && !((*m)->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED))

-                timeout = BUS_DEFAULT_TIMEOUT;

+        if (timeout == 0 && !((*m)->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED)) {

+                r = sd_bus_get_method_call_timeout(bus, &timeout);

+                if (r < 0)

+                        return r;

+        }

         r = sd_bus_message_seal(n, BUS_MESSAGE_COOKIE(*m), timeout);

         if (r < 0)

diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c

index c65e24b2d1..803f3f50d6 100644

--- a/src/libsystemd/sd-bus/sd-bus.c

+++ b/src/libsystemd/sd-bus/sd-bus.c

@@ -1651,8 +1651,11 @@ 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);

@@ -4141,3 +4144,36 @@ _public_ int sd_bus_enqueue_for_read(sd_bus *bus, sd_bus_message *m) {

         bus->rqueue[bus->rqueue_size++] = bus_message_ref_queued(m, bus);

         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;

+}

diff --git a/src/systemd/sd-bus.h b/src/systemd/sd-bus.h

index 9ba757b13d..8b6f70bd68 100644

--- a/src/systemd/sd-bus.h

+++ b/src/systemd/sd-bus.h

@@ -207,6 +207,9 @@ sd_event *sd_bus_get_event(sd_bus *bus);

 int sd_bus_get_n_queued_read(sd_bus *bus, uint64_t *ret);

 int sd_bus_get_n_queued_write(sd_bus *bus, uint64_t *ret);

+int sd_bus_set_method_call_timeout(sd_bus *bus, uint64_t usec);

+int sd_bus_get_method_call_timeout(sd_bus *bus, uint64_t *ret);

+

 int sd_bus_add_filter(sd_bus *bus, sd_bus_slot **slot, sd_bus_message_handler_t callback, void *userdata);

 int sd_bus_add_match(sd_bus *bus, sd_bus_slot **slot, const char *match, sd_bus_message_handler_t callback, void *userdata);

 int sd_bus_add_match_async(sd_bus *bus, sd_bus_slot **slot, const char *match, sd_bus_message_handler_t callback, sd_bus_message_handler_t install_callback, void *userdata);