Applets can now define a shutdown callback function, just like the
multiplexer. It is especially usefull to get the abort reason. This will be
pretty useful to get the status code from the SPOP stream to report it at
the SPOe filter level.
The related issue is #2502.
When appctx_buf_available() is called, it now sets APPCTX_FL_IN_MAYALLOC
or APPCTX_FL_OUT_MAYALLOC depending on the reportedly permitted buffer
allocation, and these flags are cleared when the said buffers are
allocated. For now they're not used for anything else.
A static variable trash_chunk was used as implicit buffer in most of
stats output function. It was a oneline buffer uses as temporary storage
before emitting to the final applet or CLI buffer.
Replaces it by a buffer defined in show_stat_ctx structure. This allows
to retrieve it in most of stats output function. An additional parameter
was added for the function where context was not already used. This
renders the code cleaner and will allow to split stats.c in several
source files.
As a result of a new member into show_stat_ctx, per-command context max
size has increased. This forces to increase APPLET_MAX_SVCCTX to ensure
pool size is big enough. Increase it to 128 bytes which includes some
extra room for the future.
Rings are keeping a lock only for the list, which apparently doesn't
need anything more than an mt_list, so let's first turn it into that
before dropping the lock. There should be no visible effect.
An issue was introduced when zero-copy forwarding was added to the stats and
cache applets. There is no test to be sure the upper layer is ready to use
the zero-copy forwarding. So these applets refuse to deliver the response
into the applet's output buffer if the zero-copy forwarding is supported by
the opposite endpoint. It is especially an issue when a filter, like the
compression, is in-use on the response channel.
Because of this bug, the response is not delivered and the applet is woken
up in loop to produce data.
To fix the issue, an appctx flag was added, APPCTX_FL_FASTFWD, to know when
the zero-copy forwarding is in-use. We rely on this flag to not fill the
outbuf in the applet's I/O handler.
No backport needed.
Default .rcv_buf and .snd_buf functions that applets can use are now
specialized to manipulate raw buffers or HTX buffers.
Thus a TCP applet should use appctx_raw_rcv_buf() and appctx_raw_snd_buf()
while HTTP applet should use appctx_htx_rcv_buf() and appctx_htx_snd_buf().
Note that the appctx is now directly passed to these functions instead of
the SC.
This patch introduces the support for the callback function responsible to
produce data via the zero-copy forwarding mechanism. There is no
implementation for now. But <to_forward> field was added in the appctx
structure to let an applet inform how much data it want to forward. It is
not mandatory but it will be used during the zero-copy forwarding
negociation.
There is no shutdown for reads and send with applets. Both are performed
when the appctx is released. So instead of 2 flags, like for
muxes/connections, only one flag is used. But the idea is the same:
acknowledge the event at the applet level.
The appctx state was never really used as a state. It is only used to know
when an applet should be freed on the next wakeup. This can be converted to
a flag and the state can be removed. This is what this patch does.
Dedicated appctx flags to report EOI, EOS and errors (pending or terminal) were
added with the functions to set these flags. It is pretty similar to what it
done on most of muxes.
Till now, we've extended the appctx state to add some flags. However, the
field name is misleading. So a bitfield was added to handle real flags. And
helper functions to manipulate this bitfield were added.
For now, it is not usable, but this patch introduce the support of callback
functions, in the applet structure, to exchange data between channels and
applets. It is pretty similar to callback functions defined by muxes.
It is the first patch of a series aimed to align applets on connections.
Here, dedicated buffers are added for applets. For now, buffers are
initialized and helpers function to deal with allocation are added. In
addition, flags to report allocation failures or full buffers are also
introduced. <inbuf> will be used to push data to the applet from the stream
and <outbuf> will be used to push data from the applet to the stream.
The CLI payload syntax has some limitation, it can't handle payloads
with empty lines, which is a common problem when uploading a PEM file
over the CLI.
This patch implements a way to customize the ending pattern of the CLI,
so we can't look for other things than empty lines.
A char cli_payload_pat[8] is used in the appctx to store the customized
pattern. The pattern can't be more than 7 characters and can still empty
to match an empty line.
The cli_io_handler() identifies the pattern and stores it, and
cli_parse_request() identifies the end of the payload.
If the customized pattern between "<<" and "\n" is more than 7
characters, it is not considered as a pattern.
This patch only implements the parser for the 'stats socket', another
patch is needed for the 'master CLI'.
In order to allow users to dump internal states using a specific key
without changing the global one, we're introducing a key in the CLI's
appctx. This key is preloaded from the global one when "set anon on"
is used (and if none exists, a random one is assigned). And the key
can optionally be assigned manually for the whole CLI session.
A "show anon" command was also added to show the anon state, and the
current key if the users has sufficient permissions. In addition, a
"debug dev hash" command was added to test the feature.
The "ctx" and "st2" parts in the appctx were marked for removal in 2.7
and were emulated using memcpy/memset etc for possible external code.
Let's remove this now.
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.
Now at least it makes it obvious that it's the stream endpoint descriptor
and not an endpoint. There were few changes thanks to the previous refactor
of the flags.
After some discussion we found that the cs_endpoint was precisely the
descriptor for a stream endpoint, hence the naturally coming name,
stream endpoint constructor.
This patch renames only the type everywhere and the new/init/free functions
to remain consistent with it. Future patches will address field names and
argument names in various code areas.
Applets were moved at the same level than multiplexers. Thus, gradually,
applets code is changed to be less dependent from the stream. With this
commit, the frontend appctx are ready to own the session. It means a
frontend appctx will be responsible to release the session.
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.
Now that the CLI's print context is alone in the appctx, it's possible
to refine the appctx's ctx layout so that the cli part matches exactly
a regular svcctx, and as such move the CLI context into an svcctx like
other applets. External code will still build and work because the
struct cli perfectly maps onto the struct cli_print_ctx that's located
into svc.storage. This is of course only to make a smooth transition
during 2.6 and will disappear immediately after.
A tiny change had to be applied to the opentracing addon which performs
direct accesses to the CLI's err pointer in its own print function. The
rest uses the standard cli_print_* which were the only ones that needed
a small change.
The whole "ctx.cli" struct could be tagged as deprecated so that any
possibly existing external code that relies on it will get build
warnings, and the comments in the struct are pretty clear about the
way to fix it, and the lack of future of this old API.
Just like for the TCP service, let's move the context away from
appctx.ctx. A new struct hlua_http_ctx was defined, reserved in
hlua_applet_http_init() and used everywhere else. Similarly, the
task dump code will no more report decoded stack traces in case
these services would be involved. That may be solved later.
The use-service mechanism for Lua in TCP mode relies on the
hlua_tcp storage in appctx->ctx. We can move its definition to
hlua.c and simply use appctx_reserve_svcctx() to reserve and access
the stoage. One tiny side effect is that the task dump used in panics
will not show anymore the Lua call stack in its trace. For this a
better API is needed from the Lua code to expose a function that does
the job from an appctx.
The Lua cosockets were using appctx.ctx.hlua_cosocket. Let's move this
to a local definition of "hlua_csk_ctx" in hlua.c, which is allocated
from the appctx by hlua_socket_new(). There's a notable change which is
that, while previously the xref link with the peer was established with
the appctx, it's now in the hlua_csk_ctx. This one must then hold a
pointer to the appctx. The code was adjusted accordingly, and now that
part of the code doesn't use the appctx.ctx anymore.
The context was moved to a local definition in the cache code, and
there's nothing specific to the cache anymore in the appctx. The
struct is stored into the appctx's storage area via the svcctx.
This one has been misused for a while as well, it's time to deprecate it
since we don't use it anymore. It will be removed in 2.7 and for now is
only marked as deprecated. Since we need to guarantee that it's zeroed
before starting any applet or CLI command, it was moved into an anonymous
union where its sibling is not marked as deprecated so that we can
continue to initialize it without triggering a warning.
If you found this commit after a bisect session you initiated to figure
why you got some build warnings and don't know what to do, have a look
at the code that deals with the "show fd", "show sess" or "show servers"
commands, as it's supposed to be self-explanatory about the tiny changes
to apply to your code to port it. If you find APPLET_MAX_SVCCTX to be
too small for your use case, either kindly ask for a tiny extension
(and try to get your code merged), or just use a pool.
The generic context variables p0/p1/p2, i0/i1, o0/o1 have been abused
and causing trouble for too long, it's time to remove them now that
they are not used anymore.
However the risk that external code still uses them is not nul and we
had not warned before about their removal. Let's mark them deprecated
in 2.6 and removed in 2.7. This will let external code continue to work
(as well as it could if it misuses them), with a strong encouragement
on updating it.
If you found this commit after a bisect session you initiated to figure
why you got some build warnings and don't know what to do, have a look
at the code that deals with the "show fd", "show env" or "show servers"
commands, as it's supposed to be self-explanatory about the tiny changes
to apply to your code to port it. If you find APPLET_MAX_SVCCTX to be
too small for your use case, either kindly ask for a tiny extension
(and try to get your code merged), or just use a pool.
The httpclient already uses its own pointer and only used to store this
single pointer into the appctx.ctx field. Let's just move it to the
svcctx and remove this entry from the appctx union.
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.
These two commands use distinct parse/release functions but a common
iohandler, thus they need to keep the same context. It was created
under the name "commit_cacrlfile_ctx" and holds a large part of the
pointers (6) and the ca_type field that helps distinguish between
the two commands for the I/O handler. It looks like some of these
fields could have been merged since apparently the CA part only
uses *cafile* and the CRL part *crlfile*, while both old and new
are of type cafile_entry and set only for each type. This could
probably even simplify some parts of the code that tries to use
the correct field.
These fields were the last ones to be migrated thus the appctx's
ssl context could finally be removed.
The command doesn't really need any storage since there's only a parser,
but since it used this context, there might have been plans for extension,
so better continue with a persistent one. Only old_ckchs, new_ckchs, and
path were being used from the appctx's ssl context. There ones moved to
the local definition, and the two former ones were removed from the appctx
since not used anymore.
This command only really uses old_ckchs, cur_ckchs and the index
in which the transaction was stored. The new structure "show_cert_ctx"
only has these 3 fields, and the now unused "cur_ckchs" and "index"
could be removed from the shared ssl context.
Now this command doesn't share any context anymore with "show cafile"
nor with the other commands. The previous "cur_cafile_entry" field from
the applet's ssl context was removed as not used anymore. Everything was
moved to show_crlfile_ctx which only has 3 fields.
Saying that the layout and usage of the various variables in the ssl
applet context is a mess would be an understatement. It's very hard
to know what command uses what fields, even after having moved away
from the mix of cli and ssl.
Let's extract the parts used by "show cafile" into their own structure.
Only the "show_all" field would be removed from the ssl ctx, the other
fields are still shared with other commands.
This context is used by CLI keywords registered by Lua. We can take
it out of the appctx and use the generic command context allocation so
that the appctx doesn't have to declare a specific one anymore. The
context is created during parsing.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing (both in the CLI and HTTP).
The change looks large but it's particularly mechanical. The context
initialization appears in stats.c and http_ana.c. The context is used
in stats.c and resolvers.c since "show stat resolvers" points there.
That's the reason why the definition moved to stats.h. "show info"
and "show stat" continue to share the same state definition for now.
Nothing else was modified.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing. The code also uses st2 which deserves being
addressed in separate commit.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing. Many commands, including pure parsers, use this
context but that's not a problem as it's designed to be used this way.
Due to this, many lines are changed but that's in fact a replacement of
"appctx->ctx.map" with "ctx->". Note that the code also uses st2 which
deserves being addressed in separate commit.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing. The code also uses st2 which deserves being
addressed in separate commit.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing.
The code still has room for improvement, such as in the "flags" field
where bits are hard-coded, but they weren't modified.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing.
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.
The "show ssl cert" command mixes some generic pointers from the
"ctx.cli" struct with context-specific ones from "ctx.ssl" while both
are in a union. Amazingly, despite the use of both p0 and i0 to store
respectively a pointer to the current ckchs and a transaction id, there
was no overlap with the other pointers used during these operations,
but should these fields be reordered or slightly updated this will break.
Comments were added above the faulty functions to indicate which fields
they are using.
This needs to be backported to 2.5.
The "show ssl ca-file <name>" command mixes some generic pointers from
the "ctx.cli" struct and context-specific ones from "ctx.ssl" while both
are in a union. The i0 integer used to store the current ca_index overlaps
with new_crlfile_entry which is thus harmless for now but is at the mercy
of any reordering or addition of these fields. Let's add dedicated fields
into the ssl structure for this.
Comments were added on top of the affected functions to indicate what they
use.
This needs to be backported to 2.5.
