consumerd: kernel-consumer.cpp: iterate on list using list_iteration_adapter

Change-Id: I4464898e56cc88baa9a9b2b4c56461d95f342ac0
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: consumer.cpp: iterate on list using list_iteration_adapter

Change-Id: Iad57a1bfdce8b2b3f14702e93f2eceb4ff535f6a
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

urcu: add list_iteration_adapter

Add a type-safe cds_list iteration adapter. Like those provided for
the lfht, this adapter provides type-safe range-for semantics for
cds_list structures.

Change-Id: I03d3b3c31911d495c9c6187000400563a3d05ad8
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: ust-consumer.cpp: iterate on lfht using lfht_filtered_iteration_adapter

Change-Id: If4f54d8e79a8eb68e2214d3182150b974b806398
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: consumer.cpp: iterate on lfht using lfht_filtered_iteration_adapter

Change-Id: I6f7e66d8446e1ebc05679a61fd190053f252902f
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: consumer-timer.cpp: iterate on lfht using lfht_filtered_iteration_adapter

Change-Id: I3fc6eab351d901379e2ebcbf81e98d7b54c09586
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: consumer-stream.cpp: iterate on lfht using lfht_filtered_iteration_adapter

Change-Id: I625c1a942fc7aa635d78a62cf468b17651596412
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

urcu: add lfht_filtered_iteration_adapter helper

The urcu lfht macros often make use of caa_container_of (and other equivalent
variations) which use offsetof. Unfortunately, offsetof is conditionally
supported by compilers for non-POD types.

The tree already has lttng::utils::container_of to work around this
problem. This new utils makes it possible to iterate on the
elements of an lfht that match a given key without using those macros. Those iterations are the
main reason such warnings are emitted. The interface of
lfht_filtered_iteration_adapter also allows the use of ranged-for loops.

Change-Id: I9acd3fa9f6523de8006bc9107bcca6b6b654d6fa
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: consumer.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Icecd70d1023847b1489b298e4c04625bac4ebcc9
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: ust-consumer.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Idbbfd6be4666bca420faf408241f5f195818981a
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

common: fd-tracker.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ic28cf4f9a8534540f2e28dd5d69a146367280a9b
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

common: trace-chunk.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ia05a6b974a9bafac993de76a781a22be487e94cd
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust-registry-session.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I0bc5ff2754be9ba417c6fa16535cf20cd23875f3
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust-registry-channel.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ie415952021ef795259b9290e4b16d68051403524
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: tracker.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I96b0cd3bfe84357f9ec09d254a6d7f8757c52c69
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: trace-ust.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I5f87aebb6d8e4fc0ef6a4088faf0b7b1a84f37d0
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: snapshot.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I826575008b4ba2d828ad5ac52dc28d78ccca5e7d
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: session.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I2deae4866e0664e32cc40b891fc9e19b9936d66e
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: save.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I760ad9294584718e308775af65279688c2f58c65
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: rotation-thread.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I00f293b25e8747058c643ba63c07813a8d9a24ec
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: manage-kernel.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Id6a47ca1971f48dec5563085fa9e5affd48a1567
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: lttng-syscall.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ib4439701c48b64b2244b346c86c7b1abb55503c4
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: notification-thread-events.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I15de31ca184c255b4a7540c2bf15f90ddf633da0
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: kernel.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ib129073617fc79c0dc9844129e637cac3d715598
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: event.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I12292f505e9f867898c92bcf6cbd81c10204d5d8
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: event-notifier-error-accounting.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I8a4486f86e634187439b8e6c13fdd1a52fd051de
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: context.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Idbcd23b281188732f1746e9f1f911c527b1f0903
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: consumer.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ie970c9da116aa7daa87287366dc4935353152bbb
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: cmd.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I6118ba8c0b5177f4c82b3c2bac77e9bc2eefecc1
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: buffer-registry.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I75daca3d9556c36bf2f08ec2c4c0184f2a2939e6
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: agent.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I4c590968f244bbffc4f685a611bfc8ec28c46688
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: agent-thread.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I059c11d8820ffb8416f265a59e21b66d884d722d
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: viewer-stream.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Idd3de68df6d9a81b3b04d8bc36a24aad14333916
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: viewer-session.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ice79de9905f6fd374c6de897541ac7915a3f8231
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: stream.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I42d455ed488a5992705a5e59ac55104da948b592
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: session.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: I113be144c1a7da100106b12d85a244f603472fed
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: main.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ibe839a6733432e2ed464e1785569ed92087cf329
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust-app.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Ibe4990750a371f67d41b02061500ab8b1cdbe60e
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: live.cpp: iterate on lfht using lfht_iteration_adapter

Change-Id: Id738d57f3bdfc26e08dc865dfdfed06834a09bc7
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Clean-up: sessiond: ust-ctl-internal: fix clang-tidy warnings

Change-Id: I797e49ed73524d19decb9fc53a5423ccfd5df7a1
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

clang-tidy: LTTNG_IOCTL_CHECK can use const return variable

clang-tidy reports:
kernel-ctl/kernel-ctl.cpp:70:9: warning: variable '_ioctl_ret' of type 'int' can be declared 'const' [misc-const-correctness]

Change-Id: I87ca5168eeca6af3e9ec459a1887493df1a51793
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Fix: sessiond: missing include causes multiple conflicting definitions

clang-tidy reports that
/root/lttng-tools/src/bin/lttng-sessiond/ust-ctl-internal.hpp:346:3: error: redefinition of 'LTTNG_PACKED' with a different type: 'struct lttng_ust_ctl_integer_type' vs 'struct lttng_ust_ctl_consumer_channel_attr' [clang-diagnostic-error]
  346 | } LTTNG_PACKED;

Indeed, that header is missing macros.hpp causing LTTNG_PACKED
to be misinterpreted.

Change-Id: I9a0ec916e7ad1c4d926f4d9a33dd6a85fb5b809c
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

clang-tidy: cppcoreguidelines-special-member-functions

clang-tidy reports an infringement of
cppcoreguidelines-special-member-functions[1] for
_scoped_rcu_read_lock, iterator, session_not_found_error,
and session_not_found_error.

The copy constructor, move constructor, and assignment operators
are deleted when they are not explicitly defined.

[1] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c21-if-you-define-or-delete-any-copy-move-or-destructor-function-define-or-delete-them-all

Change-Id: I1ec5470fed8ddf30025d7c71994bff9bafcfbf56
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

clang-tidy: remove performance-enum-size

Specifying the size of enumerators is verbose and provides dubious
performance benefits for most of our uses. Silence the warning.

Change-Id: I2dd482437f649f031b5b425d8952360bbe8ceae0
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: lttng_consumer_channel: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I69a15b9ad2e086d02beabb5c5f98d54d2ebf538d
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

consumerd: lttng_consumer_stream: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I1b8075c3ab3bdda7a345c3278ee251c6f6ee1023
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: iterate on ust_app_ht using lfht_iteration_adapter

offsetof conditionally support for non-POD types and is used by
the cds_lfht_for_each_[...] macros. Replace them with
lfht_iteration_adapter which also provides ranged-for semantics.

Change-Id: I7759c7e6e0ae5a83a8c3a2e98b74d3c3c1993af7
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_app_channel: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I29980d41d068b29a41f8148188d66a636ea5b46f
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_app_ctx: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I9d3616ccccd15d94447456df415ead2b9b4ff2c3
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: delete_ust_app_channel: iterate on lfht using lfht_iteration_adapter

offsetof conditionally support for non-POD types and is used by
the cds_lfht_for_each_[...] macros. Replace them with
lfht_iteration_adapter which also provides ranged-for semantics.

Change-Id: I163697d83f235f46a1d70b596a34b6e010ec4169
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_app_event: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: Ica13ae34db7c0fd04118d0e80c7ae71b77f66ad6
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_id_tracker_node: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I6c45b7d5138152728f67885ac5cc00ea1bc1603a
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Clean-up: sessiond: automatic memory management of ltt_ust_event

Simplify trace_ust_create_event by wrapping the created ltt_ust_event
in a unique_ptr until it is returned (on success).

Change-Id: I1b14df589f30d4cd19c9712b70f6c5656335123b
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ltt_ust_event: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I043c6a01ea4f96624d21bb034e545503995a2794
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: consumer_socket: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I49b36b3ba7be6f4cacde7f44022db459c97bf950
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: index_ht_entry: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: Ic2ed13700b8258b274aef9153ebc9d2a6a3536f3
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_error_accounting_entry: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I8b9167ad2e8100ed9a9f99d2ef23a8859713838d
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_channel: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: Ib00bfa536d9412824d49f7c8bff429b0aa03762e
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: buffer_reg_uid: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I96a42df9c82ad6b520d3b53a6445159bce692120
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: agent_event: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I28f5b7db71ce0c7a7d0ff367d88a8350bd66d988
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: viewer_stream: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: Ied676a7003749a82b0ae4eeb8a1bcedb0e081673
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: relay_session: use lttng::utils::container_of

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng::utils::container_of.

Change-Id: I0fb69c7132665ea0ee3067445884ec1115ba9872
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: use lfht_iteration_adapter to iterate on stream indices

offsetof conditionally support for non-POD types and is used by
the cds_lfht_for_each_[...] macros. Replace them with
lfht_iteration_adapter which also provides ranged-for semantics.

Change-Id: Id1460004322e1e778a1affd41c82527a05190f59
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

relayd: offsetof conditionally supported for non-POD types

caa_container_of makes use of offsetof which is conditionally
supported for non-POD types. Replace its use by
lttng_ht_node_container_of.

Change-Id: If2f19ab1aba8c59cf9ca2e0d5b815a396512b2d9
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

urcu: add lfht_iteration_adapter helper

The urcu lfht macros often make use of caa_container_of (and other
equivalent variations) which use offsetof. Unfortunately, offsetof is
conditionally supported by compilers for non-POD types.

The tree already has lttng::utils::container_of to work around this
problem. This new utils makes it possible to iterate on all of the
elements of an lfht without using those macros. Those iterations are the
main reason such warnings are emitted. The interface of
lfht_iteration_adapter also allows the use of ranged-for loops.

Change-Id: I61906e025bd0dd7512f02180700f3ddb3c9cf3ca
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: manage syscall table allocation using std::vector

Transitioning to the use of std::vector to manage the allocation and
resizing of the syscall table allows us to do away with memset() of the
syscall structure. The memset becomes problematic when lttng_ht_node_*
becomes non-POD in a follow-up change.

Change-Id: I94096782360f85ffffb0f72d188224af15e54d07
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Fix: remove use of offset_of for ust_app_session lists

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I17429be1ce0a48257b75532582552720aaec1e0d

Fix: sessiond: g++ reports shm_path truncation issue

On the CI, g++ reports:
  char* strncpy(char*, const char*, size_t)' specified bound 4096 equals destination size [-Wstringop-truncation]

The shm_path provided by liblttng-ctl is truncated to PATH_MAX
regardless of its contents.

LTTN_ERR_INVALID is returned if the shm_path is not null terminated.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: Ie369f2ee368c70e2b3b41c45a69da7e6d9fa45f8

Fix: relayd: incorrect use of lfht add_unique API

cds_lfht_add_unique is misused in relay_index_add_unique. The address
of the node is used instead of the address of the key for both the
key parameter and to compute the hash of the index entry's key.

This caused problems in an upcoming change that changes the layout
of the lttng_ht node since the key is no longer the first member
of the node.

Change-Id: Iec67f78b8ced4f4e520dc0dbebda8d30e283aa38
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Adapt to LTTng-UST ABI/control API updates

Adapt to ABI/control API updates introduced by LTTng-UST commit
24f7193c9b91 ("Introduce extension points for trace hit counters")

Note that this commit reverts back to uint32_t for channel event ids.

UST notification LTTNG_UST_CTL_NOTIFY_CMD_KEY is currently handled as
-LTTNG_UST_ERR_NOSYS (TODO).

The type of the argument to is_max_event_id() is changed to
lttng::sessiond::ust::event_id to match the newly introduced event_id
type definition. Likewise for the registry_channel _next_event_id
member.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I6299b07c02d35b067aed5e94f11353d3cc14f24c

kernel: Add new counter ABI IOCTL macros

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Depends-on: lttng-ust: I1a706cf60059c7106525cf484d4a290c38e197c7
Depends-on: lttng-modules: Ide6aa85f4fc6055b7b76604b107094373d0bf874
Change-Id: I1a1d8f265e42e68632863127721e755f7948b660

sessiond: ust: Update UST definitions for counters

Update the internal ust-abi and ust-ctl headers to match LTTng-UST's
changes to support counter events.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I85fdb02710eaecebab950407d12c85ebfe27615f
Depends-on: lttng-ust: I1a706cf60059c7106525cf484d4a290c38e197c7

Revert "lttng-ctl: Hide symbol introduced by fix"

This reverts commit 83f2539c5c084d853308993a05999016264be90e.
The change is only needed for stable branches.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I0ef85d857ebc391388d43bb236db7f9fbf3c4a11

Clean-up: lock-file: quote lock file path in debug logging message

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: Icf2a15768414cec93a5fcfc8d8dfeec463e550a8

lttng-ctl: Hide symbol introduced by fix

Michael Jeanson noticed that f94318611 mistakenly introduces a new
public symbol in liblttng-ctl.so. This change was not intended and is
due to a bad backport of a fix initially developed against the master
branch.

The master branch (and upcoming version) of LTTng-tools is built with
the -fvisibility=hidden. Hence, the initial version of the fix had no
need to hide the utils_create_lock_file symbol.

Since the supported stable releases (2.12 and 2.13) are not built with
those options, that symbol has to be explicitly marked as hidden.

Reported-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I874538317617003eb1c58c2d3b7b0a2bdf905ef7

sessiond: open_packets: use user_space_consumer_channel_keys util

Replace the hand-rolled consumer channel key iteration logic of
ust_app_open_packets by an iteration on the user_space_consumer_channel_keys
returned by the ltt_session.

Change-Id: Ida9eaecbc1146764df9935ca9af9cf71d267906d
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: clear_session: use user_space_consumer_channel_keys util

Replace the hand-rolled consumer channel key iteration logic of
ust_app_clear_session by an iteration on the user_space_consumer_channel_keys
returned by the ltt_session.

Change-Id: Id47af95d7cdad55581339c1a5319baf424848912
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

clang-tidy: apply suggested fixes

Apply FixIts proposed by clang-tidy (mostly missing 'const' qualifiers).

Change-Id: Ic616ddf6e826ee787c048de3f18aec18f9481532
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

refactor: session: provide an iterator over consumer data channel keys

The code iterating over the various data channel keys of the userspace domain is
relatively complex and repeated in many places. It is refactored to provide an
iterator that can be used in those various places.

Change-Id: I560484f63757b5da0313dd651724bbea9bbd6867
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust-app: Remove unused buffer_type attribute

Change-Id: Iea510844f7d1dec439b56ab509eb510e195464d8
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: ust_app: use RAII to manage ust_app_session locking

Like ltt_session, use the non_copyable_reference util to implement weak locked
reference helpers that are used instead of directly manipulating the
ust_app_session's pthread mutex.

Change-Id: I2c362f2b5944b3d8e089beabc07987b797bb5d36
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

hashtable: replace non-const iterator node accessors by a const version

The various lttng_ht_iter_get_node_* functions are not const-correct which makes
their use difficult in some places. This is mostly due to the fact that
cds_lfht_iter_get_node (from liburcu) is, itself, not const-correct.

These functions are replaced by a single templated function that is
const-correct by virtue of inlining the trivial iterator node accessor of
liburcu.

Change-Id: I4df87abedb1ec6b14eb52ce4c212a10805898954
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

clang-tidy: sessiond: superfluous static specifier

clang-tidy reports:
'get_session_registry' is a static definition in anonymous namespace; static is redundant here

Remove the redundant static specifier.

Change-Id: Iae7be221cde1f0789d3c3a560f1ea70d4d4e5e7a
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

clang-tidy: c_string_view: unmatched NOLINTBEGIN

clang-tidy reports:
'NOLINTBEGIN' comment without a subsequent 'NOLINTEND' comment

If a specific warning is mentionned as part of the NOLINTBEGIN clause, it must
also be mentionned in the matching NOLINTEND clause. Otherwise, clang-tidy
doesn't match them.

Change-Id: I6adef610227b162ba8a5715c3b426e4c49a1b346
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: propagate the use of ltt_session::locked_ref

The mix of managed and unmanaged ltt_session references makes their use
potentially confusing. Move to managed locked references for most of the client
request processing paths.

Change-Id: Iecb1668969ba07acfd84aa25127adb0addddbf10
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: introduce ltt_session::locked_ref look-up functions

Introduce ltt_session::locked_ref look-up functions and use them at the various
sites performing session look-ups by id or name.

The users of those look-up functions are refactored to make them exception-safe.
The biggest change is that process_client_msg is now exception-safe. The
functions are also moved inside of the ltt_session class as static methods. This
namespaces them implicitly.

A number of functions that expect a locked ltt_session are modified to accept an
ltt_session::locked_ref, thus enforcing the locking assumptions of the session
at compile time.

Change-Id: If9e4f8b25d03fa8d36a5898dd421da947ec4030c
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Exception: make source location print-out optional

The project-specific exceptions are changed to not include the source location
as part of the exception's message (return of what()) since it is unsuitable in
some contexts (the output of the lttng client for example).

Moreover, the exceptions are modified to provide their own message formatting
instead of relying on the user doing it at the site at which it is thrown since
that formatting is often repetitive. The sites at which the exceptions are
thrown can still augment the exceptions with more context.

The intention of our exceptions is that they still contain the requisite context
to change the print-out based on their members; that context should not be baked
into the message string at the site at which the exception is thrown.

Change-Id: I2733b58d4daf6b9fffc1221c9d03ffef2e246893
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: transition session_list synchronization from pthread to std

In order to allow the use of RAII to manage the locking in the client command
handler (process_client_msg), the session list's synchronization primitives are
changed to use those of libstd.

No change in behavior is intended by this change.

Change-Id: I6367e25557b05e16a48436304791cd7a37dc8904
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

sessiond: rename locked_ptr to locked_ref

The locked_ref semantics garantee that an instance of an is locked and that it
exists (it can't be null). It is currently implemented with a unique_ptr, but
that will most likely change in the future to enforce the non-null requirement.

Change-Id: I6442840f944ded1ddc46cad3d23e8e0fe8fef586
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Clean-up: sessiond: session.hpp: remove duplicated comment

Change-Id: I65eeb7af77bf9160f94bf6f9c381aeddccb4df31
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Clean-up: sessiond: client.cpp: list of inclusions

Correct some inconsistencies in the list of inclusions in client.cpp:
  - include headers under common using angle-brackets
  - only include the top-level lttng.h lttng-ctl header

Change-Id: I1dcbacf9d4546205752f2083e1f95f958fbbfe83
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Fix: sessiond: unchecked null-termination of session name

Change-Id: I56e7d21aafe3eb0472caca59dd6ff578760378f2
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

vscode: export MI_XSD_PATH and LD_LIBRARY_PATH in gdb wrapper

vscode fails to launch a session daemon using the libtool wrapper on machines
that don't have lttng installed since the XSD can't be loaded.

Export the MI_XSD_PATH to point to the file in the source tree to allow the
daemon to launch.

Moreover, launching the session daemon fails since it can't find
liblttng-ctl.so.0. Adding the library's .libs to LD_LIBRARY_PATH works around
the issue.

Change-Id: I52929b858917e5a103e067e6861cbdb5172744be
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

Fix: consumerd: consumed size miscomputed during statistics sampling

Issue observed
==============

When specifying a size-based automatic rotation, sessions sometimes continuously
rotate after the first size-based rotation is triggered.

Steps to reproduce:

  $ ./lttng create the_test
  $ ./lttng enable-channel -u the_channel
  $ ./lttng enable-rotation --size=32M
  $ ./lttng enable-event -ua --channel the_channel
  $ ./lttng start
  # Produce more than 32MiB of tracing data and stop the application(s), then
  # observe a rotation occuring on every expiration of the channel's monitor timer.

Cause
=====

The consumer daemon samples statistics of the various streams it monitors on
every expiration of their channel's "monitor" timer. One of the statistic it
maintains is the channel's total consumed size.

Once the stats are collected, the consumer sends a channel statistics sample
message to the session daemon. One of the fields of this message is the amount
of data that was consumed for the channel since the last statistics sample was
sent. The session daemon relies on that information to aggregate the consumed
size a session based on the consumed sizes of its various channels.

The consumer maintains a per-channel 'last_consumed_size_sample_sent' which is
used to compute the amount of data consumed since the last statistics sample was
sent to the session daemon. The computation is erroneous since the count sent to
the session daemon is 'the channel's total consumed data amount' minus 'the data
consumed since the last statistics sample'.

Solution
========

The counter maintained on a per-channel basis is now
consumed_size_as_of_last_sample_sent: the total amount of data consumed for that
channel as of the last statistics sample. On every expiration of the monitor
timer, the total amount of data consumed for the channel is determined and the
difference from that counter is sent to the sessiond daemon. The counter is then
updated with the latest computed value.

Known drawbacks
===============

None.

Change-Id: I327fde946826ab1da0b6511a13132f3afba1ac16
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

tests: Make test_per_application_leaks more robust

Observed issue
==============

On some systems (e.g. sles15sp4, RHEL 7), test_per_application_leaks
would fail spuriously.

Cause
=====

When walking the the FDs in `/proc/XX/fds`, the symbolic links exist but
link to unlinked files. E.g.

```
lrwx------ 1 root root 64 May 22 14:49 /proc/83578/fd/58 -> '/dev/shm/shm-ust-consumer-83578 (deleted)'
```

Solution
========

The test has been modified to loop, waiting for the post-destroy shm
count to drop back to the post-start count. In the case of a failure,
the test will hang forever but doesn't fail spuriously.

Known drawbacks
===============

None.

Change-Id: Id3c8a9f6db83fe888e79b8f06cb8308b4d90da87
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

lttng: Indicate file path and error reason when open_config fails

Observed issue
==============

In a test environment where the configuration file had been chowned to
no longer be writeable by the current user, `lttng` commands would work
but return a non-zero exit code and print `Error: Unable to create
config file`.

This doesn't give the user much information to work with to address the
issue.

Solution
========

The `PWARN` macro is used to print the file_path and reason when the
call to `fopen` fails.

This is done since the `file_path` percolated up to where the existing
error message is may be null for multiple reasons (eg. allocation
failure).

Known drawbacks
===============

The output of `PWARN` is inconsistent with the output used for most of
the `lttng` client.

Eg.

```
$ lttng create
Spawning a session daemon
Session auto-20240415-151450 created.
Traces will be output to /home/lttng-traces/auto-20240415-151450
PWARN - 15:14:50.420628389 [1184515/1184515]: fopen '/home/.lttngrc': Permission denied (in open_config() at conf.cpp:57)
Error: Unable to create config file
```

Change-Id: I5a9253fb02f3a712e7c5c2567311920dc33d36c7
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

lttng: Add PWARN macro

Change-Id: Id6d15e094b8fe7ef779022e44d8414214af3444a
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

docs: lttng-sessiond(8): bitness mix-up in env variable name

The section about the --consumerd64-path parameter erroneously refers to
the 32-bit consumer daemon binary environment
variable (LTTNG_CONSUMERD32_BIN).

It is modified to mention LTTNG_CONSUMERD64_BIN.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I338d204382b8bfca952abf604fe82277b7b08226

.clang-tidy: remove modernize-concat-nested-namespaces

The concatenated namespace syntax (e.g. namespace my::ns::woah{}) was
introduced in C++17 while this project is built as C++11. Leaving this
rule it in the .clang-tidy only adds noise (and salt to the wound).

Change-Id: Ib9550aa602fbcccc7500b14603dfd698fd7b69de
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

tests: Correct use of taskset in snapshot tests

Observed issue
==============

While investigating potential changes to how buffers are flushed
during snapshots, I discovered that the changes made the small
overwrite test flaky.

After investigation, the issue appears to be a problem with the test
that was exposed by the other changes.

Cause
=====

`taskset` handles its arguments more strictly than many other CLI
programs, and the argument order used is not valid. As the return
of the taskset invocation in the test isn't validated, there was
little indication of the issue save a warning that is easily lost
in the text.

The following example demonstrates the situation:

```
$ bash -x test.sh
+ taskset -p 910843
pid 910843's current affinity mask: f
+ echo 0
0
+ ./tests/utils/testapp/gen-ust-events/gen-ust-events
Process 910845 has 4 cpus in its affinity set
        CPU 0 is set? 1
        CPU 1 is set? 1
        CPU 2 is set? 1
        CPU 3 is set? 1
+ taskset -c 0 -p 910843
taskset: failed to execute -p: No such file or directory
+ echo 127
127
+ ./tests/utils/testapp/gen-ust-events/gen-ust-events
Process 910849 has 4 cpus in its affinity set
        CPU 0 is set? 1
        CPU 1 is set? 1
        CPU 2 is set? 1
        CPU 3 is set? 1
+ taskset -pc 0 910843
pid 910843's current affinity list: 0-3
pid 910843's new affinity list: 0
+ echo 0
0
+ ./tests/utils/testapp/gen-ust-events/gen-ust-events
Process 910853 has 1 cpus in its affinity set
        CPU 0 is set? 1
```

Solution
========

Correct the invocation of taskset and add a check on its return code
when used to set the cpu affinity of the current process.

Known drawbacks
===============

None.

Change-Id: Ia629121624532746431875b2031dd65df207666d
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>