Commit Graph

147 Commits

Author SHA1 Message Date
Willy Tarreau
40a9c32e3a CLEANUP: stconn: rename cs_{i,o}{b,c} to sc_{i,o}{b,c}
We're starting to propagate the stream connector's new name through the
API. Most call places of these functions that retrieve the channel or its
buffer are in applets. The local variable names are not changed in order
to keep the changes small and reviewable. There were ~92 uses of cs_ic(),
~96 of cs_oc() (due to co_get*() being less factorizable than ci_put*),
and ~5 accesses to the buffer itself.
2022-05-27 19:33:34 +02:00
Willy Tarreau
d0a06d52f4 CLEANUP: applet: use applet_put*() everywhere possible
This applies the change so that the applet code stops using ci_putchk()
and friends everywhere possible, for the much saferapplet_put*() instead.
The change is mechanical but large. Two or three functions used to have no
appctx and a cs derived from the appctx instead, which was a reminiscence
of old times' stream_interface. These were simply changed to directly take
the appctx. No sensitive change was performed, and the old (more complex)
API is still usable when needed (e.g. the channel is already known).

The change touched roughly a hundred of locations, with no less than 124
lines removed.

It's worth noting that the stats applet, the oldest of the series, could
get a serious lifting, as it's still very channel-centric instead of
propagating the appctx along the chain. Given that this code doesn't
change often, there's no emergency to clean it up but it would look
better.
2022-05-27 19:33:34 +02:00
Willy Tarreau
026e8fb290 CLEANUP: stconn: tree-wide rename stconn states CS_ST/SB_* to SC_ST/SB_*
This also follows the natural naming. There are roughly 238 changes, all
totally trivial. conn_stream-t.h has become completely void of any
"conn_stream" related stuff now (except its name).
2022-05-27 19:33:34 +02:00
Willy Tarreau
cb04166525 CLEANUP: stconn: tree-wide rename stream connector flags CS_FL_* to SC_FL_*
This follows the natural naming. There are roughly 100 changes, all
totally trivial.
2022-05-27 19:33:34 +02:00
Willy Tarreau
7cb9e6c6ba CLEANUP: stream: rename "csf" and "csb" to "scf" and "scb"
These are the stream connectors, let's give them consistent names. The
patch is large (405 locations) but totally trivial.
2022-05-27 19:33:34 +02:00
Willy Tarreau
4596fe20d9 CLEANUP: conn_stream: tree-wide rename to stconn (stream connector)
This renames the "struct conn_stream" to "struct stconn" and updates
the descriptions in all comments (and the rare help descriptions) to
"stream connector" or "connector". This touches a lot of files but
the change is minimal. The local variables were not even renamed, so
there's still a lot of "cs" everywhere.
2022-05-27 19:33:34 +02:00
Christopher Faulet
6095d57701 MINOR: applet: Add API to start applet on a thread subset
In the same way than for the tasks, the applets api was changed to be able
to start a new appctx on a thread subset. For now the feature is
disabled. Only appctx_new_here() is working. But it will be possible to
start an appctx on a specific thread or a subset via a mask.
2022-05-17 16:13:22 +02:00
Christopher Faulet
aee57fc277 MEDIUM: sink: Refactor sink forwarder appctx creation
A .init callback function is defined for the sink_forward_applet applet.
This function finishes the appctx startup by calling
appctx_finalize_startup() and its handles the stream customization.
2022-05-17 16:13:22 +02:00
Christopher Faulet
2ae25ea24b MINOR: sink: Add a ref to sink in the sink_forward_target structure
This change is required to be able to refactor the init stage of appctx. It
is now possible to directly get the sink from a forward target.
2022-05-17 16:13:22 +02:00
Christopher Faulet
92202da2da MINOR: applet: Let the frontend appctx release the session
The session created for frontend applets is now totally owns by the
corresponding appctx. It means the appctx is now responsible to release
it. This removes the hack in stream_free() about frontend applets to be sure
to release the session.
2022-05-17 16:13:21 +02:00
Willy Tarreau
6796a06278 CLEANUP: conn_stream: merge cs_new_from_{mux,applet} into cs_new_from_endp()
The two functions became exact copies since there's no more special case
for the appctx owner. Let's merge them into a single one, that simplifies
the code.
2022-05-13 14:28:48 +02:00
Willy Tarreau
0698c80a58 CLEANUP: applet: remove the unneeded appctx->owner
This one is the pointer to the conn_stream which is always in the
endpoint that is always present in the appctx, thus it's not needed.
This patch removes it and replaces it with appctx_cs() instead. A
few occurences that were using __cs_strm(appctx->owner) were moved
directly to appctx_strm() which does the equivalent.
2022-05-13 14:28:48 +02:00
Willy Tarreau
cba8838e59 CLEANUP: ring: pass the ring watch flags to ring_attach_cli(), not in ctx.cli
The ring watch flags (wait, seek end) were dangerously passed via ctx.cli.i0
from "show buf" in sink.c:cli_parse_show_events(), or implicitly reset in
"show errors". That's very unconvenient, difficult to follow, and prone to
short-term breakage.

Let's pass an extra argument to ring_attach_cli() to take these flags, now
defined in ring-t.h as RING_WF_*, and let the function set them itself
where appropriate (still ctx.cli.i0 for now).
2022-05-06 18:13:36 +02:00
Willy Tarreau
42cc831abf CLEANUP: sink: use the generic context to store the forwarder's context
Instead of having a struct that contains a single pointer in the appctx
context, let's directly use the generic context pointer and get rid of
the now unused sft.ptr entry.
2022-05-06 18:13:36 +02:00
Willy Tarreau
03bd3952a6 MEDIUM: stream: remove the confusing SF_ADDR_SET flag
This flag is no longer needed now that it must always match the presence
of a destination address on the backend conn_stream. Worse, before previous
patch, if it were to be accidently removed while the address is present, it
could result in a leak of that address since alloc_dst_address() would first
be called to flush it.

Its usage has a long history where addresses were stored in an area shared
with the connection, but as this is no longer the case, there's no reason
for putting this burden onto application-level code that should not focus
on setting obscure flags.

The only place where that made a small difference is in the dequeuing code
in case of queue redistribution, because previously the code would first
clear the flag, and only later when trying to deal with the queue, would
release the address. It's not even certain whether there would exist a
code path going to connect_server() without calling pendconn_dequeue()
first (e.g. retries on queue timeout maybe?).

Now the pendconn_dequeue() code will rely on SF_ASSIGNED to decide to
clear and release the address, since that flag is always set while in
a server's queue, and its clearance implies that we don't want to keep
the address. At least it remains consistent and there's no more risk of
leaking it.
2022-05-02 16:56:01 +02:00
Christopher Faulet
6b0a0fb2f9 CLEANUP: tree-wide: Remove any ref to stream-interfaces
Stream-interfaces are gone. Corresponding files can be safely be removed. In
addition, comments are updated accordingly.
2022-04-13 15:10:16 +02:00
Christopher Faulet
a0bdec350f MEDIUM: stream-int/conn-stream: Move blocking flags from SI to CS
Remaining flags and associated functions are move in the conn-stream
scope. These flags are added on the endpoint and not the conn-stream
itself. This way it will be possible to get them from the mux or the
applet. The functions to get or set these flags are renamed accordingly with
the "cs_" prefix and updated to manipualte a conn-stream instead of a
stream-interface.
2022-04-13 15:10:15 +02:00
Christopher Faulet
da098e6c17 MINOR: stream-int/conn-stream: Move si_shut* and si_chk* in conn-stream scope
si_shutr(), si_shutw(), si_chk_rcv() and si_chk_snd() are moved in the
conn-stream scope and renamed, respectively, cs_shutr(), cs_shutw(),
cs_chk_rcv(), cs_chk_snd() and manipulate a conn-stream instead of a
stream-interface.
2022-04-13 15:10:15 +02:00
Christopher Faulet
62e757470a MEDIUM: stream-int/conn-stream: Move stream-interface state in the conn-stream
The stream-interface state (SI_ST_*) is now in the conn-stream. It is a
mechanical replacement for now. Nothing special. SI_ST_* and SI_SB_* were
renamed accordingly. Utils functions to manipulate these infos were moved
under the conn-stream scope.

But it could be good to keep in mind that this part should be
reworked. Indeed, at the CS level, we only need to know if it is ready to
receive or to send. The state of conn-stream from INI to EST is only used on
the server side. The client CS is immediately set to EST. Thus current
SI_ST_* states should probably be moved to the stream to reflect the server
connection state during the establishment stage.
2022-04-13 15:10:15 +02:00
Christopher Faulet
8abe712749 MINOR: stream-int: Remove SI_FL_NOLINGER/NOHALF to rely on CS flags instead
Flags to disable lingering and half-close are now handled at the conn-stream
level. Thus SI_FL_NOLINGER and SI_FL_NOHALF stream-int flags are replaced by
CS_FL_NOLINGER and CS_FL_NOHALF conn-stream flags.
2022-04-13 15:10:14 +02:00
Christopher Faulet
8da67aae3e MEDIUM: stream-int/conn-stream: Move src/dst addresses in the conn-stream
The source and destination addresses at the applicative layer are moved from
the stream-interface to the conn-stream. This simplifies a bit the code and
it is a logicial step to remove the stream-interface.
2022-04-13 15:10:14 +02:00
Christopher Faulet
908628c4c0 MEDIUM: tree-wide: Use CS util functions instead of SI ones
At many places, we now use the new CS functions to get a stream or a channel
from a conn-stream instead of using the stream-interface API. It is the
first step to reduce the scope of the stream-interfaces. The main change
here is about the applet I/O callback functions. Before the refactoring, the
stream-interface was the appctx owner. Thus, it was heavily used. Now, as
far as possible,the conn-stream is used. Of course, it remains many calls to
the stream-interface API.
2022-04-13 15:10:14 +02:00
Christopher Faulet
9ec2f4dc7c MAJOR: conn-stream: Share endpoint struct between the CS and the mux/applet
The conn-stream endpoint is now shared between the conn-stream and the
applet or the multiplexer. If the mux or the applet is created first, it is
responsible to also create the endpoint and share it with the conn-stream.
If the conn-stream is created first, it is the opposite.

When the endpoint is only owned by an applet or a mux, it is called an
orphan endpoint (there is no conn-stream). When it is only owned by a
conn-stream, it is called a detached endpoint (there is no mux/applet).

The last entity that owns an endpoint is responsible to release it. When a
mux or an applet is detached from a conn-stream, the conn-stream
relinquishes the endpoint to recreate a new one. This way, the endpoint
state is never lost for the mux or the applet.
2022-04-13 15:10:14 +02:00
Christopher Faulet
a9e8b3979d MEDIUM: conn-stream: Pre-allocate endpoint to create CS from muxes and applets
It is a transient commit to prepare next changes. Now, when a conn-stream is
created from an applet or a multiplexer, an endpoint is always provided. In
addition, the API to create a conn-stream was specialized to have one
function per type.

The next step will be to share the endpoint structure.
2022-04-13 15:10:14 +02:00
Christopher Faulet
b669d684c0 MEDIUM: conn-stream: Be able to pass endpoint to create a conn-stream
It is a transient commit to prepare next changes. It is possible to pass a
pre-allocated endpoint to create a new conn-stream. If it is NULL, a new
endpoint is created, otherwise the existing one is used. There no more
change at the conn-stream level.

In the applets, all conn-stream are created with no pre-allocated
endpoint. But for multiplexers, an endpoint is systematically created before
creating the conn-stream.
2022-04-13 15:10:14 +02:00
Christopher Faulet
9388204db1 MAJOR: conn-stream: Invert conn-stream endpoint and its context
This change is only significant for the multiplexer part. For the applets,
the context and the endpoint are the same. Thus, there is no much change. For
the multiplexer part, the connection was used to set the conn-stream
endpoint and the mux's stream was the context. But it is a bit strange
because once a mux is installed, it takes over the connection. In a
wonderful world, the connection should be totally hidden behind the mux. The
stream-interface and, in a lesser extent, the stream, still access the
connection because that was inherited from the pre-multiplexer era.

Now, the conn-stream endpoint is the mux's stream (an opaque entity for the
conn-stream) and the connection is the context. Dedicated functions have
been added to attached an applet or a mux to a conn-stream.
2022-04-13 15:10:14 +02:00
Christopher Faulet
2479e5f775 MEDIUM: applet: Set the appctx owner during allocation
The appctx owner is now always a conn-stream. Thus, it can be set during the
appctx allocation. But, to do so, the conn-stream must be created first. It
is not a problem on the server side because the conn-stream is created with
the stream. On the client side, we must take care to create the conn-stream
first.

This change should ease other changes about the applets bootstrapping.
2022-04-13 15:10:13 +02:00
Tim Duesterhus
7750850594 CLEANUP: Reapply ist.cocci with --include-headers-for-types --recursive-includes
Previous uses of `ist.cocci` did not add `--include-headers-for-types` and
`--recursive-includes` preventing Coccinelle seeing `struct ist` members of
other structs.

Reapply the patch with proper flags to further clean up the use of the ist API.

The command used was:

    spatch -sp_file dev/coccinelle/ist.cocci -in_place --include-headers --include-headers-for-types --recursive-includes --dir src/
2022-03-21 08:30:47 +01:00
Christopher Faulet
53fa787a07 BUG/MEDIUM: sink: Properly get the stream-int in appctx callback functions
The appctx owner is not a stream-interface anymore. It is now a
conn-stream. However, sink code was not updated accordingly. It is now
fixed.

It is 2.6-specific, no backport is needed.
2022-03-16 10:01:30 +01:00
Christopher Faulet
cda94accb1 MAJOR: stream/conn_stream: Move the stream-interface into the conn-stream
Thanks to all previous changes, it is now possible to move the
stream-interface into the conn-stream. To do so, some SI functions are
removed and their conn-stream counterparts are added. In addition, the
conn-stream is now responsible to create and release the
stream-interface. While the stream-interfaces were inlined in the stream
structure, there is now a pointer in the conn-stream. stream-interfaces are
now dynamically allocated. Thus a dedicated pool is added. It is a temporary
change because, at the end, the stream-interface structure will most
probably disappear.
2022-02-24 11:00:03 +01:00
Christopher Faulet
108ce5a70b MINOR: sink: Always access the stream-int via the conn-stream
To be able to move the stream-interface from the stream to the conn-stream,
all access to the SI is done via the conn-stream. This patch is limited to
the sink part.
2022-02-24 11:00:02 +01:00
Christopher Faulet
f835dea939 MEDIUM: conn_stream: Add a pointer to the app object into the conn-stream
In the same way the conn-stream has a pointer to the stream endpoint , this
patch adds a pointer to the application entity in the conn-stream
structure. For now, it is a stream or a health-check. It is mandatory to
merge the stream-interface with the conn-stream.
2022-02-24 11:00:02 +01:00
Christopher Faulet
13a35e5752 MAJOR: conn_stream/stream-int: move the appctx to the conn-stream
Thanks to previous changes, it is now possible to set an appctx as endpoint
for a conn-stream. This means the appctx is no longer linked to the
stream-interface but to the conn-stream. Thus, a pointer to the conn-stream
is explicitly stored in the stream-interface. The endpoint (connection or
appctx) can be retrieved via the conn-stream.
2022-02-24 11:00:02 +01:00
Christopher Faulet
dd0b144c3a BUG/MINOR: sink: Use the right field in appctx context in release callback
In the release callback, ctx.peers was used instead of ctx.sft. Concretly,
it is not an issue because the appctx context is an union and these both
fields are structures with a unique pointer. But it will be a problem if
that changes.

This patch must be backported as far as 2.2.
2022-01-28 17:56:18 +01:00
Christopher Faulet
16f16afb31 MINOR: stream: Use backend stream-interface dst address instead of target_addr
target_addr field in the stream structure is removed. The backend
stream-interface destination address is now used.
2021-10-27 11:35:59 +02:00
Willy Tarreau
beeabf5314 MINOR: task: provide 3 task_new_* wrappers to simplify the API
We'll need to improve the API to pass other arguments in the future, so
let's start to adapt better to the current use cases. task_new() is used:
  - 18 times as task_new(tid_bit)
  - 18 times as task_new(MAX_THREADS_MASK)
  - 2 times with a single bit (in a loop)
  - 1 in the debug code that uses a mask

This patch provides 3 new functions to achieve this:
  - task_new_here()     to create a task on the calling thread
  - task_new_anywhere() to create a task to be run anywhere
  - task_new_on()       to create a task to run on a specific thread

The change is trivial and will allow us to later concentrate the
required adaptations to these 3 functions only. It's still possible
to call task_new() if needed but a comment was added to encourage the
use of the new ones instead. The debug code was not changed and still
uses it.
2021-10-01 18:36:29 +02:00
Willy Tarreau
e61244631a MINOR: applet: remove the thread mask from appctx_new()
appctx_new() is exclusively called with tid_bit and it only uses the
mask to pass it to the accompanying task. There is no point requiring
the caller to know about a mask there, nor is there any point in
creating an applet outside of the context of its own thread anyway.
Let's drop this and pass tid_bit to task_new() directly.
2021-09-17 16:08:34 +02:00
Miroslav Zagorac
8a8f270f6a CLEANUP: server: a separate function for initializing the per_thr field
To avoid repeating the same source code, allocating memory and initializing
the per_thr field from the server structure is transferred to a separate
function.
2021-06-17 16:07:10 +02:00
Willy Tarreau
72faef3866 MEDIUM: global: remove dead code from nbproc/bind_proc removal
Lots of places iterating over nbproc or comparing with nbproc could be
simplified. Further, "bind-process" and "process" parsing that was
already limited to process 1 or "all" or "odd" resulted in a bind_proc
field that was either 0 or 1 during the init phase and later always 1.

All the checks for compatibilities were removed since it's not possible
anymore to run a frontend and a backend on different processes or to
have peers and stick-tables bound on different ones. This is the largest
part of this patch.

The bind_proc field was removed from both the proxy and the receiver
structs.

Since the "process" and "bind-process" directives are still parsed,
configs making use of correct values allowing process 1 will continue
to work.
2021-06-15 16:52:42 +02:00
Willy Tarreau
817538e397 BUILD: sink: include proxy.h in sink.c
It's needed for proxies_list but was missing.
2021-05-08 20:24:09 +02:00
Willy Tarreau
4bad5e2080 BUILD: sink: include tools.h in sink.c
Several functions from tools.h are used in sink.c without tools.h being
included.
2021-05-08 13:05:30 +02:00
Willy Tarreau
b205bfdab7 CLEANUP: cli/tree-wide: properly re-align the CLI commands' help messages
There were 102 CLI commands whose help were zig-zagging all along the dump
making them unreadable. This patch realigns all these messages so that the
command now uses up to 40 characters before the delimiting colon. About a
third of the commands did not correctly list their arguments which were
added after the first version, so they were all updated. Some abuses of
the term "id" were fixed to use a more explanatory term. The
"set ssl ocsp-response" command was not listed because it lacked a help
message, this was fixed as well. The deprecated enable/disable commands
for agent/health/server were prominently written as deprecated. Whenever
possible, clearer explanations were provided.
2021-05-07 11:51:26 +02:00
Ilya Shipitsin
b2be9a1ea9 CLEANUP: assorted typo fixes in the code and comments
This is 22nd iteration of typo fixes
2021-04-26 10:42:58 +02:00
Willy Tarreau
2b71810cb3 CLEANUP: lists/tree-wide: rename some list operations to avoid some confusion
The current "ADD" vs "ADDQ" is confusing because when thinking in terms
of appending at the end of a list, "ADD" naturally comes to mind, but
here it does the opposite, it inserts. Several times already it's been
incorrectly used where ADDQ was expected, the latest of which was a
fortunate accident explained in 6fa922562 ("CLEANUP: stream: explain
why we queue the stream at the head of the server list").

Let's use more explicit (but slightly longer) names now:

   LIST_ADD        ->       LIST_INSERT
   LIST_ADDQ       ->       LIST_APPEND
   LIST_ADDED      ->       LIST_INLIST
   LIST_DEL        ->       LIST_DELETE

The same is true for MT_LISTs, including their "TRY" variant.
LIST_DEL_INIT keeps its short name to encourage to use it instead of the
lazier LIST_DELETE which is often less safe.

The change is large (~674 non-comment entries) but is mechanical enough
to remain safe. No permutation was performed, so any out-of-tree code
can easily map older names to new ones.

The list doc was updated.
2021-04-21 09:20:17 +02:00
Willy Tarreau
4781b1521a CLEANUP: atomic/tree-wide: replace single increments/decrements with inc/dec
This patch replaces roughly all occurrences of an HA_ATOMIC_ADD(&foo, 1)
or HA_ATOMIC_SUB(&foo, 1) with the equivalent HA_ATOMIC_INC(&foo) and
HA_ATOMIC_DEC(&foo) respectively. These are 507 changes over 45 files.
2021-04-07 18:18:37 +02:00
Emeric Brun
94aab06e24 MEDIUM: log: support tcp or stream addresses on log lines.
An explicit stream address prefix such as "tcp6@" "tcp4@"
"stream+ipv6@" "stream+ipv4@" or "stream+unix@" will
allocate an implicit ring buffer with a forward server
targeting the given address.

This is usefull to simply send logs to a log server in tcp
and It doesn't need to declare a ring section in configuration.
2021-04-07 09:18:34 +02:00
Emeric Brun
9533a70381 MINOR: log: register config file and line number on log servers.
This patch registers the parsed file and the line where a log server
is declared to make those information available in configuration
post check.

Those new informations were added on error messages probed resolving
ring names on post configuration check.
2021-04-07 09:18:34 +02:00
Amaury Denoyelle
30c0537f5a REORG: server: use flags for parse_server
Modify the API of parse_server function. Use flags to describe the type
of the parsed server instead of discrete arguments. These flags can be
used to specify if a server/default-server/server-template is parsed.
Additional parameters are also specified (parsing of the address
required, resolve of a name must be done immediately).

It is now unneeded to use strcmp on args[0] in parse_server. Also, the
calls to parse_server are more explicit thanks to the flags.
2021-03-18 15:37:05 +01:00
Willy Tarreau
144f84a09d MEDIUM: task: extend the state field to 32 bits
It's been too short for quite a while now and is now full. It's still
time to extend it to 32-bits since we have room for this without
wasting any space, so we now gained 16 new bits for future flags.

The values were not reassigned just in case there would be a few
hidden u16 or short somewhere in which these flags are placed (as
it used to be the case with stream->pending_events).

The patch is tagged MEDIUM because this required to update the task's
process() prototype to use an int instead of a short, that's quite a
bunch of places.
2021-03-05 08:30:08 +01:00
Willy Tarreau
61cfdf4fd8 CLEANUP: tree-wide: replace free(x);x=NULL with ha_free(&x)
This makes the code more readable and less prone to copy-paste errors.
In addition, it allows to place some __builtin_constant_p() predicates
to trigger a link-time error in case the compiler knows that the freed
area is constant. It will also produce compile-time error if trying to
free something that is not a regular pointer (e.g. a function).

The DEBUG_MEM_STATS macro now also defines an instance for ha_free()
so that all these calls can be checked.

178 occurrences were converted. The vast majority of them were handled
by the following Coccinelle script, some slightly refined to better deal
with "&*x" or with long lines:

  @ rule @
  expression E;
  @@
  - free(E);
  - E = NULL;
  + ha_free(&E);

It was verified that the resulting code is the same, more or less a
handful of cases where the compiler optimized slightly differently
the temporary variable that holds the copy of the pointer.

A non-negligible amount of {free(str);str=NULL;str_len=0;} are still
present in the config part (mostly header names in proxies). These
ones should also be cleaned for the same reasons, and probably be
turned into ist strings.
2021-02-26 21:21:09 +01:00
Tim Duesterhus
a7ebffef66 BUG/MINOR: sink: Return an allocation failure in __sink_new if strdup() fails
This patch fixes GitHub issue #1023.

The function was introduced in commit 99c453d ("MEDIUM: ring: new
section ring to declare custom ring buffers."), which first appeared
in 2.2-dev9. The fix should be backported to 2.2+.
2021-01-03 20:35:45 +01:00
Christopher Faulet
26256f86e1 MINOR: stream: Pass an optional input buffer when a stream is created
It is now possible to set the buffer used by the channel request buffer when
a stream is created. It may be useful if input data are already received,
instead of waiting the first call to the mux rcv_buf() callback. This change
is mandatory to support H1 connection with no stream attached.

For now, the multiplexers don't pass any buffer. BUF_NULL is thus used to
call stream_create_from_cs().
2020-12-04 14:41:48 +01:00
Emeric Brun
fdabf49548 BUG/MAJOR: ring: tcp forward on ring can break the reader counter.
If the session is not established, the applet handler could leave
with the applet detached from the ring. At next call, the attach
counter will be decreased again causing unpredectable behavior.

This patch should be backported on branches >=2.2
2020-12-02 20:17:19 +01:00
Emeric Brun
0237c4e3f5 BUG/MEDIUM: local log format regression.
Since 2.3 default local log format always adds hostame field.
This behavior change was due to log/sink re-work, because according
to rfc3164 the hostname field is mandatory.

This patch re-introduce a legacy "local" format which is analog
to rfc3164 but with hostname stripped. This is the new
default if logs are generated by haproxy.

To stay compliant with previous configurations, the option
"log-send-hostname" acts as if the default format is switched
to rfc3164.

This patch addresses the github issue #963

This patch should be backported in branches >= 2.3.
2020-12-01 06:58:42 +01:00
Christopher Faulet
fc633b6eff CLEANUP: config: Return ERR_NONE from config callbacks instead of 0
Return ERR_NONE instead of 0 on success for all config callbacks that should
return ERR_* codes. There is no change because ERR_NONE is a macro equals to
0. But this makes the return value more explicit.
2020-11-13 16:26:10 +01:00
Willy Tarreau
9b7587a6af MINOR: connection: make sockaddr_alloc() take the address to be copied
Roughly half of the calls to sockadr_alloc() are made to copy an already
known address. Let's optionally pass it in argument so that the function
can handle the copy at the same time, this slightly simplifies its usage.
2020-10-15 21:47:56 +02:00
Emeric Brun
d3db3846c5 BUG/MEDIUM: resolve: fix init resolving for ring and peers section.
Reported github issue #759 shows there is no name resolving
on server lines for ring and peers sections.

This patch introduce the resolving for those lines.

This patch adds  boolean a parameter to parse_server function to specify
if we want the function to perform an initial name resolving using libc.

This boolean is forced to true in case of peers or ring section.

The boolean is kept to false in case of classic servers (from
backend/listen)

This patch should be backported in branches where peers sections
support 'server' lines.
2020-07-21 17:59:20 +02:00
Emeric Brun
12941c82d0 MEDIUM: log: adds log forwarding section.
Log forwarding:

It is possible to declare one or multiple log forwarding section,
haproxy will forward all received log messages to a log servers list.

log-forward <name>
  Creates a new log forwarder proxy identified as <name>.

bind <addr> [param*]
  Used to configure a log udp listener to receive messages to forward.
  Only udp listeners are allowed, address must be prefixed using
  'udp@', 'udp4@' or 'udp6@'. This supports for all "bind" parameters
  found in 5.1 paragraph but most of them are irrelevant for udp/syslog case.

log global
log <address> [len <length>] [format <format>] [sample <ranges>:<smp_size>]
    <facility> [<level> [<minlevel>]]
  Used to configure target log servers. See more details on proxies
  documentation.
  If no format specified, haproxy tries to keep the incoming log format.
  Configured facility is ignored, except if incoming message does not
  present a facility but one is mandatory on the outgoing format.
  If there is no timestamp available in the input format, but the field
  exists in output format, haproxy will use the local date.

  Example:
    global
       log stderr format iso local7

    ring myring
        description "My local buffer"
        format rfc5424
        maxlen 1200
        size 32764
        timeout connect 5s
        timeout server 10s
        # syslog tcp server
        server mysyslogsrv 127.0.0.1:514 log-proto octet-count

    log-forward sylog-loadb
        bind udp4@127.0.0.1:1514
        # all messages on stderr
        log global
        # all messages on local tcp syslog server
        log ring@myring local0
        # load balance messages on 4 udp syslog servers
        log 127.0.0.1:10001 sample 1:4 local0
        log 127.0.0.1:10002 sample 2:4 local0
        log 127.0.0.1:10003 sample 3:4 local0
        log 127.0.0.1:10004 sample 4:4 local0
2020-07-15 17:50:12 +02:00
Emeric Brun
546488559a MEDIUM: log/sink: re-work and merge of build message API.
This patch merges build message code between sink and log
and introduce a new API based on struct ist array to
prepare message header with zero copy, targeting the
log forwarding feature.

Log format 'iso' and 'timed' are now avalaible on logs line.
A new log format 'priority' is also added.
2020-07-15 17:50:12 +02:00
Ilya Shipitsin
46a030cdda CLEANUP: assorted typo fixes in the code and comments
This is 11th iteration of typo fixes
2020-07-06 14:34:32 +02:00
Emeric Brun
b39a3754d9 BUG/MINOR: log: missing timezone on iso dates.
The function timeofday_as_iso_us adds now the trailing local timezone offset.
Doing this the function could be use directly to generate rfc5424 logs.

It affects content of a ring if the ring's format is set to 'iso' and 'timed'.
Note: the default ring 'buf0' is of type 'timed'.

It is preferable NOT to backport this to stable releases unless bugs are
reported, because while the previous format is not correct and the new
one is correct, there is a small risk to cause inconsistencies in log
format to some users who would not expect such a change in a stable
cycle.
2020-07-02 17:56:11 +02:00
Emeric Brun
9f9b22c4f1 MINOR: log: add time second fraction field to rfc5424 log timestamp.
This patch adds the time second fraction in microseconds
as supported by the rfc.
2020-07-02 17:56:06 +02:00
Ilya Shipitsin
47d17182f4 CLEANUP: assorted typo fixes in the code and comments
This is 10th iteration of typo fixes
2020-06-26 11:27:28 +02:00
Willy Tarreau
b2551057af CLEANUP: include: tree-wide alphabetical sort of include files
This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
2020-06-11 10:18:59 +02:00
Willy Tarreau
36979d9ad5 REORG: include: move the error reporting functions to from log.h to errors.h
Most of the files dealing with error reports have to include log.h in order
to access ha_alert(), ha_warning() etc. But while these functions don't
depend on anything, log.h depends on a lot of stuff because it deals with
log-formats and samples. As a result it's impossible not to embark long
dependencies when using ha_warning() or qfprintf().

This patch moves these low-level functions to errors.h, which already
defines the error codes used at the same places. About half of the users
of log.h could be adjusted, sometimes revealing other issues such as
missing tools.h. Interestingly the total preprocessed size shrunk by
4%.
2020-06-11 10:18:59 +02:00
Willy Tarreau
6be7849f39 REORG: include: move cfgparse.h to haproxy/cfgparse.h
There's no point splitting the file in two since only cfgparse uses the
types defined there. A few call places were updated and cleaned up. All
of them were in C files which register keywords.

There is nothing left in common/ now so this directory must not be used
anymore.
2020-06-11 10:18:58 +02:00
Willy Tarreau
aeed4a85d6 REORG: include: move log.h to haproxy/log{,-t}.h
The current state of the logging is a real mess. The main problem is
that almost all files include log.h just in order to have access to
the alert/warning functions like ha_alert() etc, and don't care about
logs. But log.h also deals with real logging as well as log-format and
depends on stream.h and various other things. As such it forces a few
heavy files like stream.h to be loaded early and to hide missing
dependencies depending where it's loaded. Among the missing ones is
syslog.h which was often automatically included resulting in no less
than 3 users missing it.

Among 76 users, only 5 could be removed, and probably 70 don't need the
full set of dependencies.

A good approach would consist in splitting that file in 3 parts:
  - one for error output ("errors" ?).
  - one for log_format processing
  - and one for actual logging.
2020-06-11 10:18:58 +02:00
Willy Tarreau
5e539c9b8d REORG: include: move stream_interface.h to haproxy/stream_interface{,-t}.h
Almost no changes, removed stdlib and added buf-t and connection-t to
the types to avoid a warning.
2020-06-11 10:18:58 +02:00
Willy Tarreau
83487a833c REORG: include: move cli.h to haproxy/cli{,-t}.h
Almost no change except moving the cli_kw struct definition after the
defines. Almost all users had both types&proto included, which is not
surprizing since this code is old and it used to be the norm a decade
ago. These places were cleaned.
2020-06-11 10:18:58 +02:00
Willy Tarreau
3727a8a083 REORG: include: move signal.h to haproxy/signal{,-t}.h
No change was necessary. Include from wdt.c was dropped since unneeded.
2020-06-11 10:18:58 +02:00
Willy Tarreau
ba2f73d40e REORG: include: move sink.h to haproxy/sink{,-t}.h
The sink files could be moved with almost no change at since they
didn't rely on anything fancy. ssize_t required sys/types.h and
thread.h was needed for the locks.
2020-06-11 10:18:57 +02:00
Willy Tarreau
d2ad57c352 REORG: include: move ring to haproxy/ring{,-t}.h
Some includes were wrong in the type definition but beyond this no
change was needed.
2020-06-11 10:18:57 +02:00
Willy Tarreau
92b4f1372e REORG: include: move time.h from common/ to haproxy/
This one is included almost everywhere and used to rely on a few other
.h that are not needed (unistd, stdlib, standard.h). It could possibly
make sense to split it into multiple parts to distinguish operations
performed on timers and the internal time accounting, but at this point
it does not appear much important.
2020-06-11 10:18:56 +02:00
Willy Tarreau
853b297c9b REORG: include: split mini-clist into haproxy/list and list-t.h
Half of the users of this include only need the type definitions and
not the manipulation macros nor the inline functions. Moves the various
types into mini-clist-t.h makes the files cleaner. The other one had all
its includes grouped at the top. A few files continued to reference it
without using it and were cleaned.

In addition it was about time that we'd rename that file, it's not
"mini" anymore and contains a bit more than just circular lists.
2020-06-11 10:18:56 +02:00
Willy Tarreau
eb6f701b99 REORG: include: move ist.h from common/ to import/
Fortunately that file wasn't made dependent upon haproxy since it was
integrated, better isolate it before it's too late. Its dependency on
api.h was the result of the change from config.h, which in turn wasn't
correct. It was changed back to stddef.h for size_t and sys/types.h for
ssize_t. The recently added reference to MAX() was changed as it was
placed only to avoid a zero length in the non-free-standing version and
was causing a build warning in the hpack encoder.
2020-06-11 10:18:56 +02:00
Willy Tarreau
4c7e4b7738 REORG: include: update all files to use haproxy/api.h or api-t.h if needed
All files that were including one of the following include files have
been updated to only include haproxy/api.h or haproxy/api-t.h once instead:

  - common/config.h
  - common/compat.h
  - common/compiler.h
  - common/defaults.h
  - common/initcall.h
  - common/tools.h

The choice is simple: if the file only requires type definitions, it includes
api-t.h, otherwise it includes the full api.h.

In addition, in these files, explicit includes for inttypes.h and limits.h
were dropped since these are now covered by api.h and api-t.h.

No other change was performed, given that this patch is large and
affects 201 files. At least one (tools.h) was already freestanding and
didn't get the new one added.
2020-06-11 10:18:42 +02:00
Willy Tarreau
570a22b11b BUILD: sink: address build warning on 32-bit architectures
The recently added ring section post-processing added this bening
warning on 32-bit archs:

  src/sink.c: In function 'cfg_post_parse_ring':
  src/sink.c:994:15: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t {aka unsigned int}' [-Wformat=]
      ha_warning("ring '%s' event max length '%u' exceeds size, forced to size '%lu'.\n",
               ^
Let's just cast b_size() to unsigned long here.
2020-06-02 12:01:51 +02:00
Emeric Brun
975564784f MEDIUM: ring: add new srv statement to support octet counting forward
log-proto <logproto>
  The "log-proto" specifies the protocol used to forward event messages to
  a server configured in a ring section. Possible values are "legacy"
  and "octet-count" corresponding respectively to "Non-transparent-framing"
  and "Octet counting" in rfc6587. "legacy" is the default.

Notes: a separated io_handler was created to avoid per messages test
and to prepare code to set different log protocols such as
request- response based ones.
2020-05-31 10:49:43 +02:00
Emeric Brun
494c505703 MEDIUM: ring: add server statement to forward messages from a ring
This patch adds new statement "server" into ring section, and the
related "timeout connect" and "timeout server".

server <name> <address> [param*]
  Used to configure a syslog tcp server to forward messages from ring buffer.
  This supports for all "server" parameters found in 5.2 paragraph.
  Some of these parameters are irrelevant for "ring" sections.

timeout connect <timeout>
  Set the maximum time to wait for a connection attempt to a server to succeed.

  Arguments :
    <timeout> is the timeout value specified in milliseconds by default, but
              can be in any other unit if the number is suffixed by the unit,
              as explained at the top of this document.

timeout server <timeout>
  Set the maximum time for pending data staying into output buffer.

  Arguments :
    <timeout> is the timeout value specified in milliseconds by default, but
              can be in any other unit if the number is suffixed by the unit,
              as explained at the top of this document.

  Example:
    global
        log ring@myring local7

    ring myring
        description "My local buffer"
        format rfc3164
        maxlen 1200
        size 32764
        timeout connect 5s
        timeout server 10s
        server mysyslogsrv 127.0.0.1:6514
2020-05-31 10:46:13 +02:00
Emeric Brun
9f2ff3a700 BUG/MINOR: error on unknown statement in ring section.
Previously unknown statements were silently ignored.
2020-05-31 10:37:54 +02:00
Emeric Brun
99c453df9d MEDIUM: ring: new section ring to declare custom ring buffers.
It is possible to globally declare ring-buffers, to be used as target for log
servers or traces.

ring <ringname>
  Creates a new ring-buffer with name <ringname>.

description <text>
  The descritpition is an optional description string of the ring. It will
  appear on CLI. By default, <name> is reused to fill this field.

format <format>
  Format used to store events into the ring buffer.

  Arguments:
    <format> is the log format used when generating syslog messages. It may be
             one of the following :

      iso     A message containing only the ISO date, followed by the text.
              The PID, process name and system name are omitted. This is
              designed to be used with a local log server.

      raw     A message containing only the text. The level, PID, date, time,
              process name and system name are omitted. This is designed to be
              used in containers or during development, where the severity
              only depends on the file descriptor used (stdout/stderr). This
              is the default.

      rfc3164 The RFC3164 syslog message format. This is the default.
              (https://tools.ietf.org/html/rfc3164)

      rfc5424 The RFC5424 syslog message format.
              (https://tools.ietf.org/html/rfc5424)

      short   A message containing only a level between angle brackets such as
              '<3>', followed by the text. The PID, date, time, process name
              and system name are omitted. This is designed to be used with a
              local log server. This format is compatible with what the systemd
              logger consumes.

      timed   A message containing only a level between angle brackets such as
              '<3>', followed by ISO date and by the text. The PID, process
              name and system name are omitted. This is designed to be
              used with a local log server.

maxlen <length>
  The maximum length of an event message stored into the ring,
  including formatted header. If an event message is longer than
  <length>, it will be truncated to this length.

size <size>
  This is the optional size in bytes for the ring-buffer. Default value is
  set to BUFSIZE.

  Example:
    global
        log ring@myring local7

    ring myring
        description "My local buffer"
        format rfc3164
        maxlen 1200

Note: ring names are resolved during post configuration processing.
2020-05-26 08:03:15 +02:00
Willy Tarreau
d68a6927f7 Revert "MEDIUM: sink: add global statement to create a new ring (sink buffer)"
This reverts commit 957ec59571.

As discussed with Emeric, the current syntax is not extensible enough,
this will be turned to a section instead in a forthcoming patch.
2020-05-20 12:06:16 +02:00
Emeric Brun
957ec59571 MEDIUM: sink: add global statement to create a new ring (sink buffer)
This patch adds the new global statement:
ring <name> [desc <desc>] [format <format>] [size <size>] [maxlen <length>]
  Creates a named ring buffer which could be used on log line for instance.

  <desc> is an optionnal description string of the ring. It will appear on
         CLI. By default, <name> is reused to fill this field.

  <format> is the log format used when generating syslog messages. It may be
           one of the following :

    iso       A message containing only the ISO date, followed by the text.
              The PID, process name and system name are omitted. This is
              designed to be used with a local log server.

    raw       A message containing only the text. The level, PID, date, time,
              process name and system name are omitted. This is designed to be
              used in containers or during development, where the severity only
              depends on the file descriptor used (stdout/stderr). This is
              the default.

    rfc3164   The RFC3164 syslog message format. This is the default.
              (https://tools.ietf.org/html/rfc3164)

    rfc5424   The RFC5424 syslog message format.
              (https://tools.ietf.org/html/rfc5424)

    short     A message containing only a level between angle brackets such as
              '<3>', followed by the text. The PID, date, time, process name
              and system name are omitted. This is designed to be used with a
              local log server. This format is compatible with what the systemd
              logger consumes.

    timed     A message containing only a level between angle brackets such as
              '<3>', followed by ISO date and by the text. The PID, process
              name and system name are omitted. This is designed to be
              used with a local log server.

  <length> is the maximum length of event message stored into the ring,
           including formatted header. If the event message is longer
           than <length>, it would be truncated to this length.

  <name> is the ring identifier, which follows the same naming convention as
         proxies and servers.

  <size> is the optionnal size in bytes. Default value is set to BUFSIZE.

Note: Historically sink's name and desc were refs on const strings. But with new
configurable rings a dynamic allocation is needed.
2020-05-19 11:04:11 +02:00
Emeric Brun
bd163817ed MEDIUM: sink: build header in sink_write for log formats
This patch extends the sink_write prototype and code to
handle the rfc5424 and rfc3164 header.

It uses header building tools from log.c. Doing this some
functions/vars have been externalized.

facility and minlevel have been removed from the struct sink
and passed to args at sink_write because they depends of the log
and not of the sink (they remained unused by rest of the code
until now).
2020-05-19 11:04:11 +02:00
Willy Tarreau
fcf94981e4 MINOR: ring: make the parse function automatically set the handler/release
ring_attach_cli() is called by the keyword parsing function to dump a
ring to the CLI. It can only work with a specific handler and release
function. Let's make it set them appropriately instead of having the
caller know these functions. This way adding a command to dump a ring
is as simple as declaring a parsing function calling ring_attach_cli().
2019-11-15 15:48:12 +01:00
Christopher Faulet
a63a5c2c65 MINOR: sink: Set the default max length for a message to BUFSIZE
It was set to MAX_SYSLOG_LEN (1K). It is a bit short to print debug
traces. Especially when part of a buffers is dump. Now, the maximum length is
set to BUFSIZE (16K).
2019-11-15 15:10:19 +01:00
Willy Tarreau
f8340e38bf MINOR: sink: change ring buffer "buf0"'s format to "timed"
This way we now always have the events date which were really missing,
especially when used with traces :

<0>2019-09-26T07:57:25.183845 [00|h2|1|mux_h2.c:3024] receiving H2 HEADERS frame : h2c=0x1ddcad0(B,FRP) h2s=0x1dde9e0(3,HCL)
<0>2019-09-26T07:57:25.183845 [00|h2|4|mux_h2.c:2505] h2c_bck_handle_headers(): entering : h2c=0x1ddcad0(B,FRP) h2s=0x1dde9>
<0>2019-09-26T07:57:25.183846 [00|h2|4|mux_h2.c:4096] h2c_decode_headers(): entering : h2c=0x1ddcad0(B,FRP)
<0>2019-09-26T07:57:25.183847 [00|h2|4|mux_h2.c:4298] h2c_decode_headers(): leaving : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183848 [00|h2|0|mux_h2.c:2559] rcvd H2 response : h2c=0x1ddcad0(B,FRH) : [3] H2 RES: HTTP/2.0 200
<0>2019-09-26T07:57:25.183849 [00|h2|4|mux_h2.c:2560] h2c_bck_handle_headers(): leaving : h2c=0x1ddcad0(B,FRH) h2s=0x1dde9e>
<0>2019-09-26T07:57:25.183849 [00|h2|4|mux_h2.c:2866] h2_process_demux(): no more Rx data : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183849 [00|h2|4|mux_h2.c:3123] h2_process_demux(): notifying stream before switching SID : h2c=0x1dd>
<0>2019-09-26T07:57:25.183850 [00|h2|4|mux_h2.c:1014] h2s_notify_recv(): in : h2c=0x1ddcad0(B,FRH) h2s=0x1dde9e0(3,HCL)
<0>2019-09-26T07:57:25.183850 [00|h2|4|mux_h2.c:3135] h2_process_demux(): leaving : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183851 [00|h2|4|mux_h2.c:3319] h2_send(): entering : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183851 [00|h2|4|mux_h2.c:3145] h2_process_mux(): entering : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183851 [00|h2|4|mux_h2.c:3234] h2_process_mux(): leaving : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183852 [00|h2|4|mux_h2.c:3428] h2_send(): leaving with everything sent : h2c=0x1ddcad0(B,FRH)
<0>2019-09-26T07:57:25.183852 [00|h2|4|mux_h2.c:3319] h2_send(): entering : h2c=0x1ddcad0(B,FRH)

It looks like some format options could finally be separate from the sink,
or maybe enforced. For example we could imagine making the date optional
or its resolution configurable within a same buffer.

Similarly, maybe trace events would like to always emit the date even
on stdout, while traffic logs would prefer not to emit the date in the
ring buffer given that there's already one in the message.
2019-09-26 08:13:38 +02:00
Willy Tarreau
53ba9d9bcf MINOR: sink: finally implement support for SINK_FMT_{TIMED,ISO}
These formats add the date with a resolution of the microsecond before the
message fields.
2019-09-26 08:13:38 +02:00
Willy Tarreau
7e9776ad7b MINOR: fd/log/sink: make the non-blocking initialization depend on the initialized bit
Logs and sinks were resorting to dirty hacks to initialize an FD to
non-blocking mode. Now we have a bit for this in the fd tab so we can
do it on the fly on first use of the file descriptor. Previously it was
set per log server by writing value 1 to the port, or during a sink
initialization regardless of the usage of the fd.
2019-08-30 15:07:25 +02:00
Willy Tarreau
1d181e489c MEDIUM: ring: implement a wait mode for watchers
Now it is possible for a reader to subscribe and wait for new events
sent to a ring buffer. When new events are written to a ring buffer,
the applets that are subscribed are woken up to display new events.
For now we only support this with the CLI applet called by "show events"
since the I/O handler is indeed a CLI I/O handler. But it's not
complicated to add other mechanisms to consume events and forward them
to external log servers for example. The wait mode is enabled by adding
"-w" after "show events <sink>". An extra "-n" was added to directly
seek to new events only.
2019-08-30 11:58:58 +02:00
Willy Tarreau
8f24023ba0 MINOR: sink: now report the number of dropped events on output
The principle is that when emitting a message, if some dropped events
were logged, we first attempt to report this counter before going
further. This is done under an exclusive lock while all logs are
produced under a shared lock. This ensures that the dropped line is
accurately reported and doesn't accidently arrive after a later
event.
2019-08-27 17:14:19 +02:00
Willy Tarreau
9f830d7408 MINOR: sink: implement "show events" to show supported sinks and dump the rings
The new "show events" CLI keyword lists supported event sinks. When
passed a buffer-type sink it completely dumps it.

no drops at all during attachment even at 8 millon evts/s.
still missing the attachment limit though.
2019-08-27 17:14:19 +02:00
Willy Tarreau
4ed23ca0e7 MINOR: sink: add support for ring buffers
This now provides sink_new_buf() which allocates a ring buffer. One such
ring ("buf0") of 1 MB is created already, and may be used by sink_write().
The sink's creation should probably be moved somewhere else later.
2019-08-27 17:14:19 +02:00
Willy Tarreau
a1426de5aa MINOR: sink: now call the generic fd write function
Let's not mess up with fd-specific code, locking nor message formating
here, and use the new generic function instead. This substantially
simplifies the sink_write() code and makes it more agnostic to the
output representation and storage.
2019-08-27 17:14:19 +02:00
Willy Tarreau
799e9ed62b MINOR: sink: set the fd-type sinks to non-blocking
Just like we used to do for the logs, we must disable blocking on FD
output except if it's a terminal.
2019-08-27 17:14:18 +02:00
Willy Tarreau
973e662fe8 MINOR: sink: add a support for file descriptors
This is the most basic type of sink. It pre-registers "stdout" and
"stderr", and is able to use writev() on them. The writev() operation
is locked to avoid mixing outputs. It's likely that the registration
should move somewhere else to take into account the fact that stdout
and stderr are still opened or are closed.
2019-08-22 20:21:00 +02:00
Willy Tarreau
67b5a161b4 MINOR: sink: create definitions a minimal code for event sinks
The principle will be to be able to dispatch events to various destinations
called "sinks". This is already done in part in logs where log servers can
be either a UDP socket or a file descriptor. This will be needed with the
new trace subsystem where we may also want to add ring buffers. And it turns
out that all such destinations make sense at all places. Logs may need to be
sent to a TCP server via a ring buffer, or consulted from the CLI. Trace
events may need to be sent to stdout/stderr as well as to remote log servers.

This patch creates a new structure "sink" aiming at addressing these similar
needs. The goal is to merge together what is common to all of them, such as
the output format, the dropped events count, etc, and also keep separately
the target identification (network address, file descriptor). Provisions
were made to have a "waiter" on the sink. For a TCP log server it will be
the task to wake up after writing to the log buffer. For a ring buffer, it
could be the list of watchers on the CLI running a "tail" operation and
waiting for new events. A lock was also placed in the struct since many
operations will require some locking, including the FD ones. The output
formats covers those in use by logs and two extra ones prepending the ISO
time in front of the message (convenient for stdio/buffer).

For now only the generic infrastructure is present, no type-specific
output is implemented. There's the sink_write() function which prepares
and formats a message to be sent, trying hard to avoid copies and only
using pointer manipulation, where the type-specific code just has to be
added. Dropped messages are already counted (for now 100% drop). The
message is put into an iovec array as it will be trivial to use with
file descriptors and sockets.
2019-08-22 20:21:00 +02:00