There is the variable to start from (or environ) and an option to stop
after dumping the first one, just like "show fd". Let's have a small
locally-defined context with these two fields.
The "show fd" command used to rely on cli.i0 for the fd, and st2 just
to decide whether to stop after the first value or not. It could have
been possible to decide to use just a negative integer to dump a single
value, but it's as easy and more durable to declare a two-field struct
show_fd_ctx for this.
Historically the CLI was a second access to the stats and we've continued
to initialize only the stats part when initializing the CLI. Let's make
sure we do that on the whole ctx instead. It's probably not more needed
at all nowadays but better stay on the safe side.
Instead of using existing fields and having to put keyword-specific
contexts in the applet definition, let's have the appctx provide a
generic storage area that's currently large enough for existing CLI
commands and small applets, and a function to allocate that storage.
The function will be responsible for verifying that the requested size
fits in the area so that the caller doesn't need to add specific checks;
it is validated during development as this size is static and will
not change at runtime. In addition the caller doesn't even need to
free() the area since it's part of an existing context. For the
caller's convenience, a context pointer "svcctx" for the command is
also provided so that the allocated area can be placed there (or
possibly any other one in case a larger area is needed).
The struct's layout has been temporarily complicated by adding one
level of anonymous union on top of the "ctx" one. This will allow us
to preserve "ctx" during 2.6 for compatibility with possible external
code and get rid of it in 2.7. This explains why the diff extends to
the whole "ctx" union, but a "git show -b" shows that only one extra
layer was added. In order to make both the svcctx pointer and its
storage accessible without further enlarging the appctx structure,
both svcctx and the storage share the same storage as the ctx part.
This is done by having them placed in the union with a protected
overlapping area for svcctx, for which a shadow member is also
present in the storage area:
union {
void* svcctx; // variable accessed by services
struct {
void *shadow; // shadow of svcctx;
char storage[]; // where most services store their data
};
union { // older commands store here and ignore svcctx
...
} ctx;
};
I.e. new applications will use appctx->svcctx while older ones will be
able to continue to use appctx->ctx.*
The whole area (including the pointer's context) is zeroed before any
applet is initialized, and before CLI keyword processor's first invocation,
as it is an important part of the existing keyword processors, which makes
CLI keywords effectively behave like applets.
This command was introduced in 1.8 with commit eceddf722 ("MEDIUM: cli:
'show cli sockets' list the CLI sockets") but its yielding doesn't work.
Each time it enters, it restarts from the last bind_conf but enumerates
all listening sockets again, thus it loops forever. The risk that it
happens in field is low but it easily triggers on port ranges after
400-500 sockets depending on the length of their addresses:
global
stats socket /tmp/sock1 level admin
stats socket 192.168.8.176:30000-31000 level operator
$ socat /tmp/sock1 - <<< "show cli sockets"
(...)
ipv4@192.168.8.176:30426 operator all
ipv4@192.168.8.176:30427 operator all
ipv4@192.168.8.176:30428 operator all
ipv4@192.168.8.176:30000 operator all
ipv4@192.168.8.176:30001 operator all
ipv4@192.168.8.176:30002 operator all
^C
This patch adds the minimally needed restart point for the listener so
that it can easily be backported. Some more cleanup is needed though.
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.
Only CS_EP_ERROR flag is now removed from the endpoint when a reset is
performed. When a new the endpoint is allocated, flags are preserved. It is
the caller responsibility to remove other flags, depending on its need.
Concretly, during a connection retry or a L7 retry, we must preserve
flags. In tcpcheck and the CLI, we reset flags.
This patch is 2.6-specific. No backport needed.
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.
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.
si_retnclose() is used to send a reply to a client before closing. There is
no use on the server side, in spite of the function is generic. Thus, it is
renamed stream_retnclose() and moved into the stream scope. The function now
handle a stream and explicitly send a message to the client.
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.
Only the server side is concerned by the stream-interface error type. It is
useless to have an err_type field on the client side. So, it is now move to
the stream. SI_ET_* are renames STRM_ET_* and moved in stream-t.h header
file.
The previous connection state on the client side was only used for debugging
purpose to report client close. But this may be handled when the client
stream-interface is switched from SI_ST_DIS to SI_ST_CLO.
So, there only remains the previous connection state on the server side that
is used by the stream, in process_stream(), to be able to set the correct
termination flags. Thus, instead of keeping this info in the
stream-interface for only one side, the info is now stored in the stream
itself.
Flag to not wake the stream up on I/O is now handled at the conn-stream
level. Thus SI_FL_DONT_WAKE stream-int flag is replaced by CS_FL_DONT_WAKE
conn-stream flags.
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.
Instead of relying on the conn-stream error, via CS_FL_ERR flags, we now
directly use the error at the endpoint level with the flag CS_EP_ERROR. It
should be safe to do so. But we must be careful because it is still possible
that an error is processed too early. Anyway, a conn-stream has always a
valid endpoint, maybe detached from any endpoint, but valid.
SI_FL_ERR is removed and replaced by CS_FL_ERROR. It is a transient patch
because the idea is to rely on the endpoint to handle errors at this
level. But if for any reason it is not possible, the stream-interface flags
will still be replaced.
The expiration date in the stream-interface was only used on the server side
to set the connect, queue or turn-around timeout. It was checked on the
frontend stream-interface, but never used concretely. So it was removed and
replaced by a connect expiration date in the stream itself. Thus, SI_FL_EXP
flag in stream-interfaces is replaced by a stream flag, SF_CONN_EXP.
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.
The conn_retries counter may be moved into the stream structure. It only
concerns the connection establishment. The frontend stream-interface does not
use it. So it is a logical change.
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.
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.
Like for previous keyword classes, we're sorting the output. But this
time as it's not trivial to do it with multiple words, instead we're
proceeding like the help command, we sort them on their usage message
when present, and fall back to the first word of the command when there
is no usage message (e.g. "help" command).
New function cli_list_keywords() scans the list of registered CLI keywords
and dumps them on stdout. It's now called from dump_registered_keywords()
for the class "cli".
Some keywords are valid for the master, they'll be suffixed with
"[MASTER]". Others are valid for the worker, they'll have "[WORKER]".
Those accessible only in expert mode will show "[EXPERT]" and the
experimental ones will show "[EXPERIM]".
The response analyzer of the master CLI only handles read errors. So if
there is a write error, the session remains stuck because some outgoing data
are blocked in the channel and the response analyzer waits everything to be
sent. Because the maxconn is set to 10 for the master CLI, it may be
unresponsive if this happens to many times.
Now read and write errors, timeouts and client aborts are handled.
This patch should solve the issue #1512. It must be backported as far as
2.0.
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.
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 cli part.
Because appctx is now an endpoint of the conn-stream, there is no reason to
still have the stream-interface as appctx owner. Thus, the conn-stream is
now the appctx owner.
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.
The backend conn-stream is no longer released on connection retry. This
means the conn-stream is detached from the underlying connection but not
released. Thus, during connection retries, the stream has always an
allocated conn-stream with no connection. All previous changes were made to
make this possible.
Note that .attach() mux callback function was changed to get the conn-stream
as argument. The muxes are no longer responsible to create the conn-stream
when a server connection is attached to a stream.
"mcli-debug-mode on" enables every command that were meant for a worker,
on the CLI of the master. Which mean you can issue, "show fd", show
stat" in order to debug the MASTER proxy.
You can also combine it with "expert-mode on" or "experimental-mode on"
to access to more commands.
When in expert or experimental mode on the master CLI, and issuing a
command for the master process, all commands are prefixed by
"mode-experimental -" or/and "mode-expert on -", however these commands
were not available in the master applet, so the help was issued for
each one.
Allow to set the master CLI in expert or experimental mode. No command
within the master are unlocked yet, but it gives the ability to send
expert or experimental commands to the workers.
echo "@1; experimental-mode on; del server be1/s2" | socat /var/run/haproxy.master -
echo "experimental-mode on; @1 del server be1/s2" | socat /var/run/haproxy.master -
This reverts commit ea7371e934.
This can't work correctly as we need this FD in the worker to be
inserted in the fdtab. The correct way to do it would be to cleanup the
mworker_proc in the master after the fork().
mworker_cli_sockpair_new() is used to create the socketpair CLI listener of
the worker. Its FD is referenced in the mworker_proc structure, however,
once it's assigned to the listener the reference should be removed so we
don't use it accidentally.
The same must be done in case of errors if the FDs were already closed.
Pipelined commands easily result in request buffers to wrap, and the
master-cli parser only deals with linear buffers since it needs contiguous
keywords to look for in a list. As soon as a buffer wraps, some commands
are ignored and the parser is called in loops because the wrapped data
do not leave the buffer.
Let's take the easiest path that's already used at the HTTP layer, we
simply realign the buffer if its input wraps. This rarely happens anyway
(typically once per buffer), remains reasonably cheap and guarantees this
cannot happen anymore.
This needs to be backported as far as 2.0.
When pcli_parse_request() is called with an empty buffer, it still tries
to parse it and can go on believing it finds an empty request if the last
char before the beginning of the buffer is a '\n'. In this case it overwrites
it with a zero and processes it as an empty command, doing nothing but not
making the buffer progress. This results in an infinite loop that is stopped
by the watchdog. For a reason related to another issue (yet to be fixed),
this can easily be reproduced by pipelining lots of commands such as
"show version".
Let's add a length check after the search for a '\n'.
This needs to be backported as far as 2.0.
When a shutdown is detected on the cli, we try to execute all pending
commands first before closing the connection. It is required because
commands execution is serialized. However, when the last part is a partial
command, the cli connection is not closed, waiting for more data. Because
there is no timeout for now on the cli socket, the connection remains
infinitely in this state. And because the maxconn is set to 10, if it
happens several times, the cli socket quickly becomes unresponsive because
all its slots are waiting for more data on a closed connections.
This patch should fix the issue #1512. It must be backported as far as 2.0.
Sending pipelined commands on the CLI using a semi-colon as a delimiter
has a cost that grows linearly with the buffer size, because co_getline()
is called for each word and looks up a '\n' in the whole buffer while
copying its contents into a temporary buffer.
This causes huge parsing delays, for example 3s for 100k "show version"
versus 110ms if parsed only once for a default 16k buffer.
This patch makes use of the new co_getdelim() function to support both
an LF and a semi-colon as delimiters so that it's no more needed to parse
the whole buffer, and that commands are instantly retrieved. We still
need to rely on co_getline() in payload mode as escapes and semi-colons
are not used there.
It should likely be backported where CLI processing speed matters, but
will require to also backport previous patch "MINOR: channel: add new
function co_getdelim() to support multiple delimiters". It's worth noting
that backporting it without "MEDIUM: cli: yield between each pipelined
command" would significantly increase the ratio of disconnections caused
by empty request buffers, for the sole reason that the currently slow
parsing grants more time to request data to come in. As such it would
be better to backport the patch above before taking this one.
Pipelining commands on the CLI is sometimes needed for batched operations
such as map deletion etc, but it causes two problems:
- some possibly long-running commands will be run in series without
yielding, possibly causing extremely long latencies that will affect
quality of service and even trigger the watchdog, as seen in github
issue #1515.
- short commands that end on a buffer size boundary, when not run in
interactive mode, will often cause the socket to be closed when
the last command is parsed, because the buffer is empty.
This patch proposes a small change to this: by yielding in the CLI applet
after processing a command when there are data left, we significantly
reduce the latency, since only one command is executed per call, and
we leave an opportunity for the I/O layers to refill the request buffer
with more commands, hence to execute all of them much more often.
With this change there's no more watchdog triggered on long series of
"del map" on large map files, and the operations are much less disturbed.
It would be desirable to backport this patch to stable versions after some
period of observation in recent versions.
This patch implements a simple "show version" command which returns
the version of the current process.
It's available from the master and the worker processes, so it is easy
to check if the master and the workers have the same version.
This is a minor patch that really improve compatibility checks
for scripts.
Could be backported in haproxy version as far as 2.0.
The master process encounter a crash when trying to access an old
process which left from the master CLI.
To reproduce the problem, you need a prompt to a previous worker, then
wait for this worker to leave, once it left launch a command from this
prompt. The s->target is then filled with a NULL which is dereferenced
when trying to connect().
This patch fixes the problem by checking if s->target is NULL.
Must be backported as far as 2.0.
The proxy used by the master CLI is an internal proxy and no filter are
registered on it. Thus, there is no reason to take care to set or unset
filter analyzers in the master CLI analyzers. AN_REQ_FLT_END was set on the
request channel to prevent the infinite forward and be sure to be able to
process one commande at a time. However, the only work because
CF_FLT_ANALYZE flag was used by error as a channel analyzer instead of a
channel flag. This erroneously set AN_RES_FLT_END on the request channel,
that really prevent the infinite forward, be side effet.
In fact, We must avoid this kind of trick because this only work by chance
and may be source of bugs in future. Instead, we must always keep the CLI
request analyzer and add an early return if the response is not fully
processed. It happens when the CLI response analyzer is set.
This patch must be backported as far as 2.0.
With the master worker, the seamless reload was still requiring an
external stats socket to the previous process, which is a pain to
configure.
This patch implements a way to use the internal socketpair between the
master and the workers to transfer the sockets during the reload.
This way, the master will always try to transfer the socket, even
without any configuration.
The master will still reload with the -x argument, followed by the
sockpair@ syntax. ( ex -x sockpair@4 ). Which use the FD of internal CLI
to the worker.
Since recent 2.5 commit c8cac04bd ("MEDIUM: listener: deprecate "process"
in favor of "thread" on bind lines"), the "process" bind keyword may
report a warning. However some parts like the "stats socket" parser
will call such bind keywords and do not expect to face warnings, so
this will instantly cause a fatal error to be reported. A concrete
effect is that "stats socket ... process 1" will hard-fail indicating
the keyword is deprecated and will be removed in 2.7.
We must relax this test, but the code isn't designed to report warnings,
it uses a single string and only supports reporting an error code (-1).
This patch makes a special case of the ERR_WARN code and uses ha_warning()
to report it, and keeps the rest of the existing error code for other
non-warning codes. Now "process" on the "stats socket" is properly
reported as a warning.
No backport is needed.
The SHOW_TOT() and SHOW_AVG() macros used in cli_io_handler_show_activity()
produce a warning on gcc 4.7 on MIPS with threads disabled because the
compiler doesn't know that global.nbthread is necessarily non-null, hence
that at least one iteration is performed. Let's just change the loop for
a do {} while () that lets the compiler know it's always initialized. It
also has the tiny benefit of making the code shorter.
The ReloadFailed prompt in the master CLI is shown only when
failedreloads > 0. It was previously using a check on the wait mode, but
we always use the wait mode now.
The CLI's payload parser is over-complicated and as such contains more
bugs than needed. One of them is that it uses strstr() to find the
ending tag, ignoring spaces before it, while the argument locator
creates a new arg on each space, without checking if the end of the
word appears past the previously found end. This results in "<<" being
considered as the start of a new argument if preceeded by more than
one space, and the payload being damaged with a \0 inserted at the
first space or tab.
Let's make an easily backportable fix for now. This fix makes sure that
the trailing zero from the first line is properly kept after '<<' and
that the end tag is looked for only as an isolated argument and nothing
else. This also gets rid of the unsuitable strstr() call and now makes
sure that strcspn() will not return elements that are found in the
payload.
For the long term the loop must be rewritten to get rid of those
unsuitable strcspn() and strstr() calls which work past each other, and
the cli_parse_request() function should be split into a tokenizer and
an executor that are used from the caller instead of letting the caller
play games with what it finds there.
This should be backported wherever CLI payload is supported, i.e. 2.0+.
This one is set whenever an FD is reported by a poller with a null owner,
regardless of the thread_mask. It has become totally meaningless because
it only indicates a migrated FD that was not yet reassigned to a thread,
but as soon as a thread uses it, the status will change to skip_fd. Thus
there is no reason to distinguish between the two, it adds more confusion
than it helps. Let's simply drop it.
Cleanup the mworker_cli_proxy_create() function by removing the
allocation and init of the proxy which is done manually, and replace it
by alloc_new_proxy(). Do the same with the free_proxy() function.
This patch also move the insertion at the end of the function.
A server name was displayed as <srv>/<proxy> instead of the reverse.
It only confuses diagnostics. This was introduced by commit 7a4a0ac71
("MINOR: cli: add a new "show fd" command") so this fix can be backport
down to 1.8.
This basically undoes the API changes that were performed by commit
0274286dd ("BUG/MAJOR: server: fix deadlock when changing maxconn via
agent-check") to address the deadlock issue: since process_srv_queue()
doesn't use the server lock anymore, it doesn't need the "server_locked"
argument, so let's get rid of it before it gets used again.
This reverts commit c83e45e9b0.
The recent changes since 5304669e1 MEDIUM: queue: make
pendconn_process_next_strm() only return the pendconn opened a tiny race
condition between stream_free() and process_srv_queue(), as the pendconn
is accessed outside of the lock, possibly while it's being freed. A
different approach is required.
This basically undoes the API changes that were performed by commit
0274286dd ("BUG/MAJOR: server: fix deadlock when changing maxconn via
agent-check") to address the deadlock issue: since process_srv_queue()
doesn't use the server lock anymore, it doesn't need the "server_locked"
argument, so let's get rid of it before it gets used again.
The server_parse_maxconn_change_request locks the server lock. However,
this function can be called via agent-checks or lua code which already
lock it. This bug has been introduced by the following commit :
commit 79a88ba3d0
BUG/MAJOR: server: prevent deadlock when using 'set maxconn server'
This commit tried to fix another deadlock with can occur because
previoulsy server_parse_maxconn_change_request requires the server lock
to be held. However, it may call internally process_srv_queue which also
locks the server lock. The locking policy has thus been updated. The fix
is functional for the CLI 'set maxconn' but fails to address the
agent-check / lua counterparts.
This new issue is fixed in two steps :
- changes from the above commit have been reverted. This means that
server_parse_maxconn_change_request must again be called with the
server lock.
- to counter the deadlock fixed by the above commit, process_srv_queue
now takes an argument to render the server locking optional if the
caller already held it. This is only used by
server_parse_maxconn_change_request.
The above commit was subject to backport up to 1.8. Thus this commit
must be backported in every release where it is already present.
The relative_pid is always 1. In mworker mode we also have a
child->relative_pid which is always equalt relative_pid, except for a
master (0) or external process (-1), but these types are usually tested
for, except for one place that was amended to carefully check for the
PROC_O_TYPE_WORKER option.
Changes were pretty limited as most usages of relative_pid were for
designating a process in stats output and peers protocol.
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.
The compiler sees the possibility of null-deref for which a path is
possible but which doesn't exist as we didn't pass a null args outside
of the help request. The test was introduced by the simplified test on
ishelp variable, so let's add it to shut the warning.
It's still very difficult to find all commands starting with a given
keyword like "set", "show" etc. Let's sort the lines by usage message,
this is much more convenient.
With ~100 commands on the CLI, it's particularly difficult to find a
specific one in the "help" output. The function used to display the
help already supports filtering on certain commands, so in the end it's
just needed to pass the argument of the help command to enable the
automatic filtering. That's what this patch does so that "help clear"
only lists commands starting with "clear" and that "help map" lists
commands containing "map" in them.
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.
Since the introduction of payload support on the CLI in 1.9-dev1 by
commit abbf60710 ("MEDIUM: cli: Add payload support"), a chunk is
temporarily allocated for the CLI to support defragmenting a payload
passed with a command. However it's only released when passing via
the CLI_ST_END state (i.e. on clean shutdown), but not on errors.
Something as trivial as:
$ while :; do ncat --send-only -U /path/to/cli <<< "show stat"; done
with a few hundreds of servers is enough see the number of allocated
trash chunks go through the roof in "show pools".
This needs to be backported as far as 2.0.
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.
Allocation error are now handled in bind_conf_alloc() functions. Thus
callers, when not already done, are also updated to catch NULL return value.
This patch may be backported (at least partially) to all stable
versions. However, it only fix errors durung configuration parsing. Thus it
is not mandatory.
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.
Slightly reorder the status flags to better match their order in the
"state" field, and also decode the "shut" state which is particularly
useful and already part of this field.
No need to keep this flag apart any more, let's merge it into the global
state. The CLI's output state was extended to 6 digits and the linger/cloned
flags moved inside the parenthesis.
For a long time we've had fdtab[].ev and fdtab[].state which contain two
arbitrary sets of information, one is mostly the configuration plus some
shutdown reports and the other one is the latest polling status report
which also contains some sticky error and shutdown reports.
These ones used to be stored into distinct chars, complicating certain
operations and not even allowing to clearly see concurrent accesses (e.g.
fd_delete_orphan() would set the state to zero while fd_insert() would
only set the event to zero).
This patch creates a single uint with the two sets in it, still delimited
at the byte level for better readability. The original FD_EV_* values
remained at the lowest bit levels as they are also known by their bit
value. The next step will consist in merging the remaining bits into it.
The whole bits are now cleared both in fd_insert() and _fd_delete_orphan()
because after a complete check, it is certain that in both cases these
functions are the only ones touching these areas. Indeed, for
_fd_delete_orphan(), the thread_mask has already been zeroed before a
poller can call fd_update_event() which would touch the state, so it
is certain that _fd_delete_orphan() is alone. Regarding fd_insert(),
only one thread will get an FD at any moment, and it as this FD has
already been released by _fd_delete_orphan() by definition it is certain
that previous users have definitely stopped touching it.
Strictly speaking there's no need for clearing the state again in
fd_insert() but it's cheap and will remove some doubts during some
troubleshooting sessions.
In preparation of merging FD_POLL* and FD_EV*, this only changes the
value of FD_POLL_* to use bits 8-15 (the second byte). The size of the
field has been temporarily extended to 32 bits already, as well as
the temporary variables that carry the new composite value inside
fd_update_events(). The resulting fdtab entry becomes temporarily
unaligned. All places making access to .ev or FD_POLL_* were carefully
inspected to make sure they were safe regarding this change. Only one
temporary update was needed for the "show fd" code. The code was only
slightly inflated at this step.
If the configuration file contains a 'unix-bind prefix' directive, and
if we use the -S option and specify a UNIX socket path, the path of the
socket will be prepended with the value of the unix-bind prefix.
For instance, if we have 'unix-bind prefix /tmp/sockets/' and we use
'-S /tmp/master-socket' on the command line, we will get this error:
Starting proxy MASTER:
cannot bind UNIX socket (No such file or directory) [/tmp/sockets/tmp/master-socket]
So this patch adds an exception, and will ignore the unix-bind prefix
for the master CLI socket.
This patch can be backported as far as 1.9.
Now the suggested keywords are sorted with the most relevant ones first
instead of scanning them all in registration order and only dumping the
proposed ones:
- "tra"
trace <module> [cmd [args...]] : manage live tracing
operator : lower the level of the current CLI session to operator
user : lower the level of the current CLI session to user
show trace [<module>] : show live tracing state
- "pool"
show pools : report information about the memory pools usage
add acl : add acl entry
del map : delete map entry
user : lower the level of the current CLI session to user
del acl : delete acl entry
- "sh ta"
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show tasks : show running tasks
set table [id] : update or create a table entry's data
show table [id]: report table usage stats or dump this table's contents
trace <module> [cmd [args...]] : manage live tracing
- "sh state"
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
set table [id] : update or create a table entry's data
show table [id]: report table usage stats or dump this table's contents
show servers state [id]: dump volatile server information (for backend <id>)
show sess [id] : report the list of current sessions or dump this session
Till now the fuzzy matching would only work on the same number of words,
but this doesn't account for commands like "show servers conn" which
involve 3 words and were not proposed when entering only "show conn".
Let's improve the situation by building the two fingerprints separately
for the correct keyword sequence and the entered one, then compare them.
This can result in slightly larger variations due to the different string
lengths but is easily compensated for. Thanks to this, we can now see
"show servers conn" when entering "show conn", and the following choices
are relevant to correct typos:
- "show foo"
show sess [id] : report the list of current sessions or dump this session
show info : report information about the running process [desc|json|typed]*
show env [var] : dump environment variables known to the process
show fd [num] : dump list of file descriptors in use
show pools : report information about the memory pools usage
- "show stuff"
show sess [id] : report the list of current sessions or dump this session
show info : report information about the running process [desc|json|typed]*
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show fd [num] : dump list of file descriptors in use
show tasks : show running tasks
- "show stafe"
show sess [id] : report the list of current sessions or dump this session
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show fd [num] : dump list of file descriptors in use
show table [id]: report table usage stats or dump this table's contents
show tasks : show running tasks
- "show state"
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show servers state [id]: dump volatile server information (for backend <id>)
It's still visible that the shorter ones continue to easily match, such
as "show sess" not having much in common with "show foo" but what matters
is that the best candidates are definitely relevant. Probably that listing
them in match order would further help.
I somehow managed to re-break the "help" command in b736458bf ("MEDIUM:
cli: apply spelling fixes for known commands before listing them")
after fixing it once. A null-deref happens when checking the args
early in the processing.
No backport is needed as this was introduced in 2.4-dev12.
There were still a very small list of functions, variables and fields
called "stats_" while they were really purely CLI-centric. There's the
frontend called "stats_fe" in the global section, which instantiates a
"cli_applet" called "<CLI>" so it was renamed "cli_fe".
The "alloc_stats_fe" function cas renamed to "cli_alloc_fe" which also
better matches the naming convention of all cli-specific functions.
Finally the "stats_permission_denied_msg" used to return an error on
the CLI was renamed "cli_permission_denied_msg".
Now there's no more "stats_something" that designates the CLI.
This is the number of args accepted on a command received on the CLI,
is has long been totally independent of stats and should not carry
this misleading "stats" name anymore.
Now instead of comparing words at an exact position, we build a fingerprint
made of all of them, so that we can check for them in any position. For
example, "show conn serv" finds "show servers conn" and that "set servers
maxconn" proposes both "set server" and "set maxconn servers".
Entering "show tls" would still emit 35 entries. By measuring the distance
between all unknown words and the candidates, we can sort them and pick the
10 most likely candidates. This works reasonably well, as now "show tls"
only proposes "show tls-keys", "show threads", "show pools" and "show tasks".
If the distance is still too high or if a word is missing, the whole
prefix list continues to be dumped, thus "show" alone will still report
the entire list of commands beginning with "show".
It's still impossible to skip a word, for example "show conn" will not
propose "show servers conn" because the distance is calculated for each
word individually. Some changes to the distance calculation to support
updating an existing map could easily address this. But this is already
a great improvement.
The error message on the CLI has become unreadable due to the long list
and it's not even sorted, making it even harder to figure the right
command.
This patch starts by looking if some of the words match something known,
and if so, will limit the listing only to those commands that start like
the current one. The "help", "prompt" and "quit" commands are always
shown to help the user try something else. Now thanks to this, typing
"add" or "del" will only list "add acl", "add map" and not 50 lines
anymore.
As a small bonus, we won't print "Unknown command" anymore in response
to the "help" command.
By doing so we can report more accurate information about what's wrong.
As a first step, we already distinguish the case of expert-only commands
from other ones.
Now that the appctx contains the master level, it greatly simplifies
all the tests, as we can simply verify that keyword levels match the
effective level without having to cheat with applet pointers. This
also allows to fold the expert test in them.
Right now the code is a bit hackish, it tests for the keyword's level
flags but checks the applet's origin to compare the bits. Let's start
by properly setting the ACCESS_MASTER_ONLY and ACCESS_MASTER flags on
the master CLI's bind_conf so that they are automatically present
all the time.
These 3 commands are functionally valid both in master and worker CLIs.
However, while they do have a valid handler, they are not permitted by
the code and work partially by chance in the master:
- "prompt" and "quit" are intercepted by the request analyser
- "help" triggers an error, which results in displaying the error
message
Let's make sure they are permitted so that we don't count errors there and
that we can report appropriate help.
This bug has always been there but it doesn't have any functional effect
at the moment since "help" can only show the error message. As such, there
is no need to backport it.
Just like with the server keywords, now's the turn of "bind" keywords.
The difference is that 100% of the bind keywords are registered, thus
we do not need the list of extra keywords.
There are multiple bind line parsers today, all were updated:
- peers
- log
- dgram-bind
- cli
$ printf "listen f\nbind :8000 tcut\n" | ./haproxy -c -f /dev/stdin
[NOTICE] 070/101358 (25146) : haproxy version is 2.4-dev11-7b8787-26
[NOTICE] 070/101358 (25146) : path to executable is ./haproxy
[ALERT] 070/101358 (25146) : parsing [/dev/stdin:2] : 'bind :8000' unknown keyword 'tcut'; did you mean 'tcp-ut' maybe ?
[ALERT] 070/101358 (25146) : Error(s) found in configuration file : /dev/stdin
[ALERT] 070/101358 (25146) : Fatal errors found in configuration.
The default proxy was passed as a variable to all parsers instead of a
const, which is not without risk, especially when some timeout parsers used
to make some int pointers point to the default values for comparisons. We
want to be certain that none of these parsers will modify the defaults
sections by accident, so it's important to mark this proxy as const.
This patch touches all occurrences found (89).
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.
this is pure cleanup, no need to backport
2116 if ((end - 1) == (payload + strlen(PAYLOAD_PATTERN))) {
2117 /* if the payload pattern is at the end */
2118 s->pcli_flags |= PCLI_F_PAYLOAD;
CID 1399833 (#1 of 1): Unused value (UNUSED_VALUE)assigned_value: Assigning value from reql to ret here, but that stored value is overwritten before it can be used.
2119 ret = reql;
2120 }
This patch fixes the issue #1048.
FD dumps are not always easy to match against netstat dumps, and often
require an lsof as a third dump. Let's emit the socket family, and the
local and remore ports when the FD is an IPv4/IPv6 socket, this will
significantly ease the matching.
A file descriptor which maps to a connection but has more than one
thread in its mask, or an FD handle that doesn't correspond to the FD,
or wiht no mux context, or an FD with no thread in its mask, or with
more than 1 million events is flagged as suspicious.
Now the show_fd helpers at the transport and mux levels return an integer
which indicates whether or not the inspected entry looks suspicious. When
an entry is reported as suspicious, "show fd" will suffix it with an
exclamation mark ('!') in the dump, that is supposed to help detecting
them.
For now, helpers were adjusted to adapt to the new API but none of them
reports any suspicious entry yet.
Just like we did for the muxes, now the transport layers will have the
ability to provide helpers to report more detailed information about their
internal context. When the helper is not known, the pointer continues to
be dumped as-is if it's not NULL. This way a transport with no context nor
dump function will not add a useless "xprt_ctx=(nil)" but the pointer will
be emitted if valid or if a helper is defined.
These ones are definitely missing from some dumps, let's report them! We
print the xprt's name instead of its useless pointer, as well as its ctx
when xprt is not NULL.
Over time the code has uglified, casting fdt.owner as a struct connection
for about everything. Let's have a const struct connection* there and take
this opportunity for passing all fields as const as well.
Additionally a misplaced closing parenthesis on the output was fixed.
conn_fd_handler() is 100% specific to socket code. It's about time
it moves to sock.c which manipulates socket FDs. With it comes
conn_fd_check() which tests for the socket's readiness. The ugly
connection status check at the end of the iocb was moved to an inlined
function in connection.h so that if we need it for other socket layers
it's not too hard to reuse.
The code was really only moved and not changed at all.
This function will be useful to check if the keyword is already registered.
Also add a define for the max number of args.
This will be needed by a next patch to fix a bug and will have to be
backported.
Following the patch b4daee ("MINOR: sock: add a check against cross
worker<->master socket activities"), this patch adds a dedicated applet
for the master CLI. It ensures that the CLI connection can't be
used with the master rights in the case of bugs.
Now we define a new sock_accept_iocb() for socket-based stream protocols
and use it as a wrapper for listener_accept() which now takes a listener
and not an FD anymore. This will allow the receiver's I/O cb to be
redefined during registration, and more specifically to get rid of the
hard-coded hacks in protocol_bind_all() made for syslog.
The previous ->accept() callback in the protocol was removed since it
doesn't have anything to do with accept() anymore but is more generic.
A few places where listener_accept() was compared against the FD's IO
callback for debugging purposes on the CLI were updated.
This listener flag indicates whether the receiver part of the listener
is specific to the master or to the workers. In practice it's only used
by the master's CLI right now. It's used to know whether or not the FD
must be closed before forking the workers. For this reason it's way more
of a receiver's property than a listener's property, so let's move it
there under the name RX_F_MWORKER. The rest of the code remains
unchanged.
We have to count unstoppable jobs which correspond to worker sockpairs, in
order to know when to count. However the way it's currently done is quite
awkward because these are counted when stopping making the stop mechanism
non-idempotent. This is definitely something we want to fix before stopping
by protocol or our listeners count will quickly go wrong. Now they are
counted when the listeners are created.
The remaining proxy states were only used to distinguish an enabled
proxy from a disabled one. Due to the initialization order, both
PR_STNEW and PR_STREADY were equivalent after startup, and they
would only differ from PR_STSTOPPED when the proxy is disabled or
shutdown (which is effectively another way to disable it).
Now we just have a "disabled" field which allows to distinguish them.
It's becoming obvious that start_proxies() is only used to print a
greeting message now, that we'd rather get rid of. Probably that
zombify_proxy() and stop_proxy() should be merged once their
differences move to the right place.
We'll need this so that it can return pointers to stacked protocol in
the future (for QUIC). In addition this removes a lot of tests for
protocol validity in the callers.
Some of them were checked further apart, or after a call to
str2listener() and they were simplified as well.
There's still a trick, we can fail to return a protocol in case the caller
accepts an fqdn for use later. This is what servers do and in this case it
is valid to return no protocol. A typical example is:
server foo localhost:1111
If a file descriptor was passed, we can optionally return it. This will
be useful for listening sockets which are both a pre-bound FD and a ready
socket.
These flags indicate whether the call is made to fill a bind or a server
line, or even just send/recv calls (like logs or dns). Some special cases
are made for outgoing FDs (e.g. pipes for logs) or socket FDs (e.g external
listeners), and there's a distinction between stream or dgram usage that's
expected to significantly help str2sa_range() proceed appropriately with
the input information. For now they are not used yet.
It's the receiver's FD that's inherited from the parent process, not
the listener's so the flag must move to the receiver so that appropriate
actions can be taken.
Some socket settings used to be retrieved via the listener and the
bind_conf. Now instead we use the receiver and its settings whenever
appropriate. This will simplify the removal of the dependency on the
listener.
The netns is common to all listeners/receivers and is used to bind the
listening socket so it must be in the receiver settings and not in the
listener. This removes some yet another set of unnecessary loops.
The interface is common to all listeners/receivers and is used to bind
the listening socket so it must be in the receiver settings and not in
the listener. This removes some unnecessary loops.
Now we don't limit ourselves to listeners found in proxies nor peers
anymore, we're instead scanning all known FDs for those marked with
".exported=1". Just doing so has significantly simplified the code,
and will later allow to yield while sending FDs if desired.
When it comes to retrieving a possible namespace name or interface
name, for now this is only performed on listeners since these are the
only ones carrying such info. Once this moves somewhere else, we'll
be able to also pass these info for UDP receivers for example, with
only tiny changes.
During a reload operation, we used to send listener options associated
with each passed file descriptor. These were passed as binary contents
for the size of the "options" field in the struct listener. This means
that any flag value change or field size change would be problematic,
the former failing to properly grab certain options, the latter possibly
causing permanent failures during this operation.
Since these two previous commits:
MINOR: reload: determine the foreing binding status from the socket
BUG/MINOR: reload: detect the OS's v6only status before choosing an old socket
we don't need this anymore as the values are determined from the file
descriptor itself.
Let's just turn the previous 32 bits to vestigal space, send them as
zeroes and ignore them on receipt. The only possible side effect is if
someone would want to roll back from a 2.3 to 2.2 or earlier, such options
might be ignored during this reload. But other forthcoming changes might
make this fail as well anyway so that's not a reason for keeping this
behavior.
The FD takeover operation might have certain impacts explaining
unexpected activities, so it's important to report such a counter
there. We thus count the number of times a thread has stolen an
FD from another thread.
DEBUG_FD was added by commit 38e8a1c in 2.2-dev, and "show fd" was
slightly modified to still allow to print orphaned/closed FDs if their
count is non-null. But bypassing the existing test made it possible
to dereference fdt.owner which can be null. Let's adjust the condition
to avoid this.
No backport is needed.
When DEBUG_FD is set at build time, we'll keep a counter of per-FD events
in the fdtab. This counter is reported in "show fd" even for closed FDs if
not zero. The purpose is to help spot situations where an apparently closed
FD continues to be reported in loops, or where some events are dismissed.
Fix the semicolon escaping which must be handled in the master CLI,
the commands were wrongly splitted and could be forwarded partially to
the target CLI.
The master CLI must not do the escaping since it forwards the commands
to another CLI. It should be able to split into words by taking care of
the escaping, but must not remove the forwarded backslashes.
This fix do the same thing as the previous patch applied to the
cli_parse_request() function, by taking care of the escaping during the
word split, but it also remove the part which was removing the
backslashes from the forwarded command.
It was not possible to escape spaces over the CLI, making impossible the
insertion of new ACL entries with spaces from the CLI.
This patch fixes the escaping of spaces over the CLI.
It is now possible to launch "add acl agents.acl My\ User\ Agent" over
the CLI.
Could be backported in all stable branches.
Should fix issue #400.
This one was confusingly called, I thought it was the cumulated number
of streams but it's the number of calls to process_stream(). Let's make
this clearer.
empty_rq and long_rq are per-loop so it makes sense to group them
together with the loop count. In addition since ctxsw and tasksw
apply in the context of these counters, let's move them as well.
More precisely the difference between wake_tasks and long_rq should
roughly correspond to the number of inter-task messages. Visually
it's much easier to spot ratios of wakeup causes now.
We have poll_drop, poll_dead and poll_skip which are confusingly named
like their poll_io and poll_exp counterparts except that they are not
per poll() call but per-fd. This patch renames them to poll_drop_fd(),
poll_dead_fd() and poll_skip_fd() for this reason.
The "show activity" output mentions a number of indicators to explain
wake up reasons but doesn't have the number of times poll() sees some
I/O. And given that multiple events can happen simultaneously, it's
not always possible to deduce this metric by subtracting.
This patch adds a new "poll_io" counter that allows one to see how
often poll() returns with at least one active FD. This should help
detect stuck events and measure various ratios of poll sub-metrics.
Since 2.1-dev2, with commit 305d5ab46 ("MAJOR: fd: Get rid of the fd cache.")
we don't have the fd_lock anymore and as such its acitvity counter is always
zero. Let's remove it from the struct and from "show activity" output, as
there are already plenty of indicators to look at.
The cache line comment in the struct activity was updated to reflect
reality as it looks like another one already got removed in the past.
Getting rid of this warning is cleaner solved using a 'fall through' comment,
because it clarifies intent to a human reader.
This patch adjust a few places that cause -Wimplicit-fallthrough to trigger:
- Fix typos in the comment.
- Remove redundant 'no break' that trips up gcc from comment.
- Move the comment out of the block when the 'case' is completely surrounded
by braces.
- Add comments where I could determine that the fall through was intentional.
Changes tested on
gcc (Debian 9.3.0-13) 9.3.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
using
make -j4 all TARGET=linux-glibc USE_OPENSSL=1 USE_LUA=1 USE_ZLIB=1 USE_PCRE2=1 USE_PCRE2_JIT=1 USE_GETADDRINFO=1
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.
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%.
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.
This one was not easy because it was embarking many includes with it,
which other files would automatically find. At least global.h, arg.h
and tools.h were identified. 93 total locations were identified, 8
additional includes had to be added.
In the rare files where it was possible to finalize the sorting of
includes by adjusting only one or two extra lines, it was done. But
all files would need to be rechecked and cleaned up now.
It was the last set of files in types/ and proto/ and these directories
must not be reused anymore.
extern struct dict server_name_dict was moved from the type file to the
main file. A handful of inlined functions were moved at the bottom of
the file. Call places were updated to use server-t.h when relevant, or
to simply drop the entry when not needed.
The files remained mostly unchanged since they were OK. However, half of
the users didn't need to include them, and about as many actually needed
to have it and used to find functions like srv_currently_usable() through
a long chain that broke when moving the file.
This one is particularly difficult to split because it provides all the
functions used to manipulate a proxy state and to retrieve names or IDs
for error reporting, and as such, it was included in 73 files (down to
68 after cleanup). It would deserve a small cleanup though the cut points
are not obvious at the moment given the number of structs involved in
the struct proxy itself.
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.
