8308 Commits

Author SHA1 Message Date
Aurelien DARRAGON
df188f145b MINOR: clock: add now_cpu_time_fast() function
Same as now_cpu_time(), but for fast queries (less accurate)
Relies on now_cpu_time() and now_mono_time_fast() is used
as a cache expiration hint to prevent now_cpu_time() from being
called too often since it is known to be quite expensive.

Depends on commit "MINOR: clock: add now_mono_time_fast() function"
2023-04-19 11:03:31 +02:00
Aurelien DARRAGON
07cbd8e074 MINOR: clock: add now_mono_time_fast() function
Same as now_mono_time(), but for fast queries (less accurate)
Relies on coarse clock source (also known as fast clock source on
some systems).

Fallback to now_mono_time() if coarse source is not supported on the system.
2023-04-19 11:03:31 +02:00
Amaury Denoyelle
0783a7b08e MINOR: listener: remove unneeded local accept flag
Remove the receiver RX_F_LOCAL_ACCEPT flag. This was used by QUIC
protocol before thread rebinding was supported by the quic_conn layer.

This should be backported up to 2.7 after the previous patch has also
been taken.
2023-04-18 17:09:34 +02:00
Amaury Denoyelle
739de3f119 MINOR: quic: properly finalize thread rebinding
When a quic_conn instance is rebinded on a new thread its tasks and
tasklet are destroyed and new ones created. Its socket is also migrated
to a new thread which stop reception on it.

To properly reactivate a quic_conn after rebind, wake up its tasks and
tasklet if they were active before thread rebind. Also reactivate
reading on the socket FD. These operations are implemented on a new
function qc_finalize_affinity_rebind().

This should be backported up to 2.7 after a period of observation.
2023-04-18 17:09:02 +02:00
Amaury Denoyelle
25174d51ef MEDIUM: quic: implement thread affinity rebinding
Implement a new function qc_set_tid_affinity(). This function is
responsible to rebind a quic_conn instance to a new thread.

This operation consists mostly of releasing existing tasks and tasklet
and allocating new instances on the new thread. If the quic_conn uses
its owned socket, it is also migrated to the new thread. The migration
is finally completed with updated the CID TID to the new thread. After
this step, the connection is thus accessible to the new thread and
cannot be access anymore on the old one without risking race condition.

To ensure rebinding is either done completely or not at all, tasks and
tasklet are pre-allocated before all operations. If this fails, an error
is returned and rebiding is not done.

To destroy the older tasklet, its context is set to NULL before wake up.
In I/O callbacks, a new function qc_process() is used to check context
and free the tasklet if NULL.

The thread rebinding can cause a race condition if the older thread
quic_dghdlrs::dgrams list contains datagram for the connection after
rebinding is done. To prevent this, quic_rx_pkt_retrieve_conn() always
check if the packet CID is still associated to the current thread or
not. In the latter case, no connection is returned and the new thread is
returned to allow to redispatch the datagram to the new thread in a
thread-safe way.

This should be backported up to 2.7 after a period of observation.
2023-04-18 17:08:34 +02:00
Amaury Denoyelle
1304d19dee MINOR: quic: delay post handshake frames after accept
When QUIC handshake is completed on our side, some frames are prepared
to be sent :
* HANDSHAKE_DONE
* several NEW_CONNECTION_ID with CIDs allocated

This step was previously executed in quic_conn_io_cb() directly after
CRYPTO frames parsing. This patch delays it to be completed after
accept. Special care have been taken to ensure it is still functional
with 0-RTT activated.

For the moment, this patch should have no impact. However, when
quic_conn thread migration on accept will be implemented, it will be
easier to remap only one CID to the new thread. New CIDs will be
allocated after migration on the new thread.

This should be backported up to 2.7 after a period of observation.
2023-04-18 17:08:28 +02:00
Amaury Denoyelle
a66e04338e MINOR: protocol: define new callback set_affinity
Define a new protocol callback set_affinity. This function is used
during listener_accept() to notify about a rebind on a new thread just
before pushing the connection on the selected thread queue. If the
callback fails, accept is done locally.

This change will be useful for protocols with state allocated before
accept is done. For the moment, only QUIC protocol is concerned. This
will allow to rebind the quic_conn to a new thread depending on its
load.

This should be backported up to 2.7 after a period of observation.
2023-04-18 16:54:52 +02:00
Amaury Denoyelle
1e959ad522 MINOR: quic: remove TID encoding in CID
CIDs were moved from a per-thread list to a global list instance. The
TID-encoded is thus non needed anymore.

This should be backported up to 2.7 after a period of observation.
2023-04-18 16:54:31 +02:00
Amaury Denoyelle
e83f937cc1 MEDIUM: quic: use a global CID trees list
Previously, quic_connection_id were stored in a per-thread tree list.
Datagram were first dispatched to the correct thread using the encoded
TID before a tree lookup was done.

Remove these trees and replace it with a global trees list of 256
entries. A CID is using the list index corresponding to its first byte.
On datagram dispatch, CID is lookup on its tree and TID is retrieved
using new member quic_connection_id.tid. As such, a read-write lock
protects each list instances. With 256 entries, it is expected that
contention should be reduced.

A new structure quic_cid_tree served as a tree container associated with
its read-write lock. An API is implemented to ensure lock safety for
insert/lookup/delete operation.

This patch is a step forward to be able to break the affinity between a
CID and a TID encoded thread. This is required to be able to migrate a
quic_conn after accept to select thread based on their load.

This should be backported up to 2.7 after a period of observation.
2023-04-18 16:54:17 +02:00
Amaury Denoyelle
66947283ba MINOR: quic: remove TID ref from quic_conn
Remove <tid> member in quic_conn. This is moved to quic_connection_id
instance.

For the moment, this change has no impact. Indeed, qc.tid reference
could easily be replaced by tid as all of this work was already done on
the connection thread. However, it is planified to support quic_conn
thread migration in the future, so removal of qc.tid will simplify this.

This should be backported up to 2.7.
2023-04-18 16:20:47 +02:00
Amaury Denoyelle
c2a9264f34 MINOR: quic: adjust quic CID derive API
ODCID are never stored in the CID tree. Instead, we store our generated
CID which is directly derived from the CID using a hash function. This
operation is done via quic_derive_cid().

Previously, generated CID was returned as a 64-bits integer. However,
this is cumbersome to convert as an array of bytes which is the most
common CID representation. Adjust this by modifying return type to a
quic_cid struct.

This should be backported up to 2.7.
2023-04-18 16:20:47 +02:00
Amaury Denoyelle
1a5cc19cec MINOR: quic: adjust Rx packet type parsing
qc_parse_hd_form() is the function used to parse the first byte of a
packet and return its type and version. Its API has been simplified with
the following changes :
* extra out paremeters are removed (long_header and version). All infos
  are now stored directly in quic_rx_packet instance
* a new dummy version is declared in quic_versions array with a 0 number
  code. This can be used to match Version negotiation packets.
* a new default packet type is defined QUIC_PACKET_TYPE_UNKNOWN to be
  used as an initial value.

Also, the function has been exported to an include file. This will be
useful to be able to reuse on quic-sock to parse the first packet of a
datagram.

This should be backported up to 2.7.
2023-04-18 16:20:47 +02:00
Amaury Denoyelle
591e7981d9 CLEANUP: quic: rename quic_connection_id vars
Two different structs exists for QUIC connection ID :
* quic_connection_id which represents a full CID with its sequence
  number
* quic_cid which is just a buffer with a length. It is contained in the
  above structure.

To better differentiate them, rename all quic_connection_id variable
instances to "conn_id" by contrast to "cid" which is used for quic_cid.

This should be backported up to 2.7.
2023-04-18 16:20:47 +02:00
Amaury Denoyelle
90e5027e46 CLEANUP: quic: remove unused scid_node
Remove unused scid_node member for quic_conn structure. It was prepared
for QUIC backend support.

This should be backported up to 2.7.
2023-04-18 16:20:47 +02:00
Amaury Denoyelle
22a368ce58 CLEANUP: quic: remove unused QUIC_LOCK label
QUIC_LOCK label is never used. Indeed, lock usage is minimal on QUIC as
every connection is pinned to its owned thread.

This should be backported up to 2.7.
2023-04-18 16:20:47 +02:00
Christopher Faulet
ca5309a9a3 MINOR: stconn: Add a flag to report EOS at the stream-connector level
SC_FL_EOS flag is added to report the end-of-stream at the SC level. It will
be used to distinguish end of stream reported by the endoint, via the
SE_FL_EOS flag, and the abort triggered by the stream, via the
SC_FL_ABRT_DONE flag.

In this patch, the flag is defined and is systematically tested everywhere
SC_FL_ABRT_DONE is tested. It should be safe because it is never set.
2023-04-17 17:41:28 +02:00
Christopher Faulet
a1d14a7c7f MINOR: stconn: Add a flag to ack endpoint errors at SC level
The flag SC_FL_ERROR is added to ack errors on the endpoint. When
SE_FL_ERROR flag is detected on the SE descriptor, the corresponding is set
on the SC. Idea is to avoid, as far as possible, to manipulated the SE
descriptor in upper layers and know when an error in the endpoint is handled
by the SC.

For now, this flag is only set and cleared but never tested.
2023-04-14 17:05:53 +02:00
Christopher Faulet
b2b1c3a6ea MINOR: channel/stconn: Replace sc_shutw() by sc_shutdown()
All reference to a shutw is replaced by an abort. So sc_shutw() is renamed
sc_shutdown(). SC app ops functions are renamed accordingly.
2023-04-14 15:02:57 +02:00
Christopher Faulet
208c712b40 MINOR: stconn: Rename SC_FL_SHUTW in SC_FL_SHUT_DONE
Here again, it is just a flag renaming. In SC flags, there is no longer
shutdown for writes but shutdowns.
2023-04-14 15:01:21 +02:00
Christopher Faulet
cfc11c0eae MINOR: channel/stconn: Replace sc_shutr() by sc_abort()
All reference to a shutr is replaced by an abort. So sc_shutr() is renamed
sc_abort(). SC app ops functions are renamed accordingly.
2023-04-14 14:54:35 +02:00
Christopher Faulet
0c370eee6d MINOR: stconn: Rename SC_FL_SHUTR in SC_FL_ABRT_DONE
Here again, it is just a flag renaming. In SC flags, there is no longer
shutdown for reads but aborts. For now this flag is set when a read0 is
detected. It is of couse not accurate. This will be changed later.
2023-04-14 14:51:22 +02:00
Christopher Faulet
df7cd710a8 MINOR: channel/stconn: Replace channel_shutw_now() by sc_schedule_shutdown()
After the flag renaming, it is now the turn for the channel function to be
renamed and moved in the SC scope. channel_shutw_now() is replaced by
sc_schedule_shutdown(). The request channel is replaced by the front SC and
the response is replace by the back SC.
2023-04-14 14:49:45 +02:00
Christopher Faulet
e38534cbd0 MINOR: stconn: Rename SC_FL_SHUTW_NOW in SC_FL_SHUT_WANTED
Because shutowns for reads are now considered as aborts, the shudowns for
writes can now be considered as shutdowns. Here it is just a flag
renaming. SC_FL_SHUTW_NOW is renamed SC_FL_SHUT_WANTED.
2023-04-14 14:46:07 +02:00
Christopher Faulet
12762f09a5 MINOR: channel/stconn: Replace channel_shutr_now() by sc_schedule_abort()
After the flag renaming, it is now the turn for the channel function to be
renamed and moved in the SC scope. channel_shutr_now() is replaced by
sc_schedule_abort(). The request channel is replaced by the front SC and the
response is replace by the back SC.
2023-04-14 14:08:49 +02:00
Christopher Faulet
573ead1e68 MINOR: stconn: Rename SC_FL_SHUTR_NOW in SC_FL_ABRT_WANTED
It is the first step to transform shutdown for reads for the upper layer
into aborts. This patch is quite simple, it is just a flag renaming.
2023-04-14 14:06:01 +02:00
Christopher Faulet
7eb837df4a MINOR: stream: Introduce stream_abort() to abort on both sides in same time
The function stream_abort() should now be called when an abort is performed
on the both channels in same time.
2023-04-14 14:04:59 +02:00
Christopher Faulet
3db538ac2f MINOR: channel: Forwad close to other side on abort
Most of calls to channel_abort() are associated to a call to
channel_auto_close(). Others are in areas where the auto close is the
default. So, it is now systematically enabled when an abort is performed on
a channel, as part of channel_abort() function.
2023-04-14 13:56:28 +02:00
Christopher Faulet
dbad8ec787 MINOR: stream: Uninline and export sess_set_term_flags() function
This function will be used to set termination flags on TCP streams from
outside of process_stream(). Thus, it must be uninlined and exported.
2023-04-14 12:13:09 +02:00
Frédéric Lécaille
fad0e6cf73 MINOR: quic: Add packet loss and maximum cc window to "show quic"
Add the number of packet losts and the maximum congestion control window computed
by the algorithms to "show quic".
Same thing for the traces of existent congestion control algorithms.

Must be backported to 2.7 and 2.6.
2023-04-13 19:20:08 +02:00
Willy Tarreau
d30e82b9f0 MINOR: receiver: reserve special values for "shards"
Instead of artificially setting the shards count to MAX_THREAD when
"by-thread" is used, let's reserve special values for symbolic names
so that we can add more in the future. For now we use value -1 for
"by-thread", which requires to turn the type to signed int but it was
already used as such everywhere anyway.
2023-04-13 17:12:50 +02:00
Amaury Denoyelle
53fc98c3bc MINOR: fd: implement fd_migrate_on() to migrate on a non-local thread
fd_migrate_on() can be used to migrate an existing FD to any thread, even
one belonging to a different group from the current one and from the
caller's. All that is needed is to make sure the FD is still valid when
the operation is performed (which is the case when such operations happen).

This is potentially slightly expensive since it locks the tgid during the
delicate operation, but it is normally performed only from an owning
thread to offer the FD to another one (e.g. reassign a better thread upon
accept()).
2023-04-13 16:57:51 +02:00
Willy Tarreau
7b44c26e13 MINOR: fd: add a lock bit with the tgid
In order to permit to migrate FDs from one thread group to another,
we'll need to be able to set a TGID that is compatible with no other
thread group. Either we use a special value or we dedicate a special
bit. Given that we already have way more bits than needed, let's just
sacrifice the topmost one to serve as a lock bit, indicating the tgid
is not valid anymore. This will make all fd_grab_tgid() fail to grab
it.

The new fd_lock_tgid() function now tries to assign a locked tgid to
an idle FD, and fd_unlock_tgid() simply drops the lock bit, revealing
the target tgid.

For now it's still unused so it must not have any effect.
2023-04-13 16:57:51 +02:00
Willy Tarreau
4d882bd800 MINOR: fd: optimize fd_claim_tgid() for use in fd_insert()
fd_claim_tgid() uses a CAS to set the desired TGID on the FD. It's only
called from fd_insert() where in the vast majority of cases, the tgid
and refcount are zero before the call. However the loop was optimized
for the case where it was equal to the desired TGID, systematically
causing one extra round in the loop there. Better start assuming a
zero value.
2023-04-13 16:57:51 +02:00
Willy Tarreau
97da942ba6 MINOR: thread: keep a bitmask of enabled groups in thread_set
We're only checking for 0, 1, or >1 groups enabled there, and we'll soon
need to be more precise and know quickly which groups are non-empty.
Let's just replace the count with a mask of enabled groups. This will
allow to quickly spot the presence of any such group in a set.
2023-04-13 16:57:51 +02:00
William Lallemand
3f210970bf BUG/MINOR: stick_table: alert when type len has incorrect characters
Alert when the len argument of a stick table type contains incorrect
characters.

Replace atol by strtol.

Could be backported in every maintained versions.
2023-04-13 14:46:08 +02:00
Willy Tarreau
7f2b3f9431 BUILD: bug.h: add a warning in the base API when unsafe functions are used
Once in a while we introduce an sprintf() or strncat() function by
accident. These ones are particularly dangerous and must never ever
be used because the only way to use them safely is at least as
complicated if not more, than their safe counterparts. By redefining
a few of these functions with an attribute_warning() we can deliver a
message to the developer who is tempted to use them. This commit does
it for strcat(), strcpy(), strncat(), sprintf(), vsprintf(). More could
come later if needed, such as strtok() and maybe a few others, but these
are less common.
2023-04-07 18:21:36 +02:00
Willy Tarreau
d499127148 MINOR: compiler: define a __attribute__warning() macro
__attribute__((deprecated)) is convenient to discourage from using
something deprecated, but gcc >= 4.3 provides __attribute__((warning(x)))
that allows to display a specific warning if something is used. This is
particularly convenient to give indications when some API parts need to
be adapted. Let's just define it as a macro that falls back to the older
deprecated attribute when not available.

It's supported on clang 14 as well but works differently and errors
out when redefined (while the main purpose precisely is to add such a
redefinition). Thus instead on clang we use deprecated(msg) which is
OK. See https://github.com/llvm/llvm-project/issues/56519
2023-04-07 18:14:28 +02:00
Willy Tarreau
988e19c607 BUILD: compiler: fix __equals_1() on older compilers
It appeared that __has_attribute() doesn't work on gcc 4.4 and older
because the concatenation of __has_attribute##x isn't resolved as a one
before being passed to __equals_1() which immediately concatenates it to
comma_for_one. We first need to pass it through an extra layer to resolve
this name to a value. The new version was tested with gcc 4.2 to 11.3.

This may be backported though it's pretty minor.
2023-04-07 18:14:28 +02:00
Olivier Houchard
ead43fe4f2 MEDIUM: compression: Make it so we can compress requests as well.
Add code so that compression can be used for requests as well.
New compression keywords are introduced :
"direction" that specifies what we want to compress. Valid values are
"request", "response", or "both".
"type-req" and "type-res" define content-type to be compressed for
requests and responses, respectively. "type" is kept as an alias for
"type-res" for backward compatibilty.
"algo-req" specifies the compression algorithm to be used for requests.
Only one algorithm can be provided.
"algo-res" provides the list of algorithm that can be used to compress
responses. "algo" is kept as an alias for "algo-res" for backward
compatibility.
2023-04-07 00:49:17 +02:00
Olivier Houchard
dea25f51b6 MINOR: compression: Count separately request and response compression
Duplicate the compression counters, so that we have separate counters
for request and response compression.
2023-04-07 00:47:04 +02:00
Olivier Houchard
db573e9c58 MINOR: compression: Store algo and type for both request and response
Make provision for being able to store both compression algorithms and
content-types to compress for both requests and responses. For now only
the responses one are used.
2023-04-07 00:46:59 +02:00
Olivier Houchard
dfc11da561 MINOR: compression: Prepare compression code for request compression
Make provision for storing the compression algorithm and the compression
context twice, one for requests, and the other for responses. Only the
response ones are used for now.
2023-04-07 00:46:55 +02:00
Olivier Houchard
3ce0f01b81 MINOR: compression: Make compression offload a flag
Turn compression offload into a flag in struct comp, instead of using
an int just for it.
2023-04-07 00:46:45 +02:00
Christopher Faulet
6bb26d41fe BUG/MUNOR: http-ana: Use an unsigned integer for http_msg flags
In the commit 2954bcc1e (BUG/MINOR: http-ana: Don't switch message to DATA
when waiting for payload), the HTTP message flags were extended and don't
fit anymore in an unsigned char. So, we must use an unsigned integer now. It
is not a big deal because there was already a 6-bytes hole in the structure,
just after the flags. Now, there are a 3-bytes hold before.

This patch should fix the issue #2105. It is 2.8-specific, no backport
needed.
2023-04-06 08:58:45 +02:00
Amaury Denoyelle
15adc4cc4e MINOR: quic: remove address concatenation to ODCID
Previously, ODCID were concatenated with the client address. This was
done to prevent a collision between two endpoints which used the same
ODCID.

Thanks to the two previous patches, first connection generated CID is
now directly derived from the client ODCID using a hash function which
uses the client source address from the same purpose. Thus, it is now
unneeded to concatenate client address to <odcid> quic-conn member.

This change allows to simplify the quic_cid structure management and
reduce its size which is important as it is embedded several times in
various structures such as quic_conn and quic_rx_packet.

This should be backported up to 2.7.
2023-04-05 11:09:57 +02:00
Amaury Denoyelle
2c98209c1c MINOR: quic: remove ODCID dedicated tree
First connection CID generation has been altered. It is now directly
derived from client ODCID since previous commit :
  commit 162baaff7ab761c411800f4ca6bef45315d7afcb
  MINOR: quic: derive first DCID from client ODCID

This patch removes the ODCID tree which is now unneeded. On connection
lookup via CID, if a DCID is not found the hash derivation is performed
for an INITIAL/0-RTT packet only. In case a client has used multiple
times an ODCID, this will allow to retrieve our generated DCID in the
CID tree without storing the ODCID node.

The impact of this two combined patch is that it may improve slightly
haproxy memory footprint by removing a tree node from quic_conn
structure. The cpu calculation induced by hash derivation should only be
performed only a few times per connection as the client will start to
use our generated CID as soon as it received it.

This should be backported up to 2.7.
2023-04-05 11:07:01 +02:00
Christopher Faulet
ffcffa8e93 MINOR: http-ana: Add a HTTP_MSGF flag to state the Expect header was checked
HTTP_MSGF_EXPECT_CHECKED is now set on the request message to know the
"Expect: " header was already handled, if any. The flag is set from the
moment we try to handle the header to send a "100-continue" response,
whether it was found or not.

This way, when we are waiting for the request payload, thanks to this flag,
we only try to handle "Expect: " header only once. Before it was performed
by changing the message state from BODY to DATA. But this has some side
effects and it is no accurate. So, it is better to rely on a flag to do so.
2023-04-05 10:33:32 +02:00
Aurelien DARRAGON
c84899c636 MEDIUM: hlua/event_hdl: initial support for event handlers
Now that the event handler API is pretty mature, we can expose it in
the lua API.

Introducing the core.event_sub(<event_types>, <cb>) lua function that
takes an array of event types <event_types> as well as a callback
function <cb> as argument.

The function returns a subscription <sub> on success.
Subscription <sub> allows you to manage the subscription from anywhere
in the script.
To this day only the sub->unsub method is implemented.

The following event types are currently supported:
  - "SERVER_ADD": when a server is added
  - "SERVER_DEL": when a server is removed from haproxy
  - "SERVER_DOWN": server states goes from up to down
  - "SERVER_UP": server states goes from down to up

As for the <cb> function: it will be called when one of the registered
event types occur. The function will be called with 3 arguments:
  cb(<event>,<data>,<sub>)

<event>: event type (string) that triggered the function.
(could be any of the types used in <event_types> when registering
the subscription)

<data>: data associated with the event (specific to each event family).

For "SERVER_" family events, server details such as server name/id/proxy
will be provided.
If the server still exists (not yet deleted), a reference to the live
server is provided to spare you from an additionnal lookup if you need
to have direct access to the server from lua.

<sub> refers to the subscription. In case you need to manage it from
within an event handler.
(It refers to the same subscription that the one returned from
core.event_sub())

Subscriptions are per-thread: the thread that will be handling the
event is the one who performed the subscription using
core.event_sub() function.

Each thread treats events sequentially, it means that if you have,
let's say SERVER_UP, then SERVER_DOWN in a short timelapse, then your
cb function will first be called with SERVER_UP, and once you're done
handling the event, your function will be called again with SERVER_DOWN.

This is to ensure event consitency when it comes to logging / triggering
logic from lua.

Your lua cb function may yield if needed, but you're pleased to process
the event as fast as possible to prevent the event queue from growing up

To prevent abuses, if the event queue for the current subscription goes
over 100 unconsumed events, the subscription will pause itself
automatically for as long as it takes for your handler to catch up.
This would lead to events being missed, so a warning will be emitted in
the logs to inform you about that. This is not something you want to let
happen too often, it may indicate that you subscribed to an event that
is occurring too frequently or/and that your callback function is too
slow to keep up the pace and you should review it.

If you want to do some parallel processing because your callback
functions are slow: you might want to create subtasks from lua using
core.register_task() from within your callback function to perform the
heavy job in a dedicated task and allow remaining events to be processed
more quickly.

Please check the lua documentation for more information.
2023-04-05 08:58:17 +02:00
Aurelien DARRAGON
4e5e26641d MINOR: proxy: add findserver_unique_id() and findserver_unique_name()
Adding alternative findserver() functions to be able to perform an
unique match based on name or puid and by leveraging revision id (rid)
to make sure the function won't match with a new server reusing the
same name or puid of the "potentially deleted" server we were initially
looking for.

For example, if you were in the position of finding a server based on
a given name provided to you by a different context:

Since dynamic servers were implemented, between the time the name was
picked and the time you will perform the findserver() call some dynamic
server deletion/additions could've been performed in the mean time.

In such cases, findserver() could return a new server that re-uses the
name of a previously deleted server. Depending on your needs, it could
be perfectly fine, but there are some cases where you want to lookup
the original server that was provided to you (if it still exists).
2023-04-05 08:58:17 +02:00
Aurelien DARRAGON
f751a97a11 MINOR: event_hdl: pause/resume for subscriptions
While working on event handling from lua, the need for a pause/resume
function to temporarily disable a subscription was raised.

We solve this by introducing the EHDL_SUB_F_PAUSED flag for
subscriptions.

The flag is set via _pause() and cleared via _resume(), and it is
checked prior to notifying the subscription in publish function.

Pause and Resume functions are also available for via lookups for
identified subscriptions.

If 68e692da0 ("MINOR: event_hdl: add event handler base api")
is being backported, then this commit should be backported with it.
2023-04-05 08:58:17 +02:00