-public:
- /*
- * With multiple writers and readers, use this lock to access
- * the registry. Can nest within the ust app session lock.
- * Also acts as a registry serialization lock. Used by registry
- * readers to serialize the registry information sent from the
- * sessiond to the consumerd.
- * The consumer socket lock nests within this lock.
- */
- pthread_mutex_t _lock;
- /* Next channel ID available for a newly registered channel. */
- uint32_t _next_channel_id = 0;
- /* Once this value reaches UINT32_MAX, no more id can be allocated. */
- uint32_t _used_channel_id = 0;
- /* Next enumeration ID available. */
- uint64_t _next_enum_id = 0;
- /* Universal unique identifier used by the tracer. */
- unsigned char _uuid[LTTNG_UUID_LEN] = {};
-
- /* session ABI description */
-
- /* Size of long, in bits */
- unsigned int _bits_per_long;
- /* Alignment, in bits */
- unsigned int _uint8_t_alignment, _uint16_t_alignment, _uint32_t_alignment,
- _uint64_t_alignment, _long_alignment;
- /* endianness: BIG_ENDIAN or LITTLE_ENDIAN */
- int _byte_order;
-
- /* Generated metadata. */
- char *_metadata = nullptr; /* NOT null-terminated ! Use memcpy. */
- size_t _metadata_len = 0, _metadata_alloc_len = 0;
- /* Length of bytes sent to the consumer. */
- size_t _metadata_len_sent = 0;
- /* Current version of the metadata. */
- uint64_t _metadata_version = 0;
-
- /*
- * Those fields are only used when a session is created with
- * the --shm-path option. In this case, the metadata is output
- * twice: once to the consumer, as ususal, but a second time
- * also in the shm path directly. This is done so that a copy
- * of the metadata that is as fresh as possible is available
- * on the event of a crash.
- *
- * root_shm_path contains the shm-path provided by the user, along with
- * the session's name and timestamp:
- * e.g. /tmp/my_shm/my_session-20180612-135822
- *
- * shm_path contains the full path of the memory buffers:
- * e.g. /tmp/my_shm/my_session-20180612-135822/ust/uid/1000/64-bit
- *
- * metadata_path contains the full path to the metadata file that
- * is kept for the "crash buffer" extraction:
- * e.g.
- * /tmp/my_shm/my_session-20180612-135822/ust/uid/1000/64-bit/metadata
- *
- * Note that this is not the trace's final metadata file. It is
- * only meant to be used to read the contents of the ring buffers
- * in the event of a crash.
- *
- * metadata_fd is a file descriptor that points to the file at
- * 'metadata_path'.
- */
- char _root_shm_path[PATH_MAX] = {};
- char _shm_path[PATH_MAX] = {};
- char _metadata_path[PATH_MAX] = {};
- /* File-backed metadata FD */
- int _metadata_fd = -1;
-
- /*
- * Hash table containing channels sent by the UST tracer. MUST
- * be accessed with a RCU read side lock acquired.
- */
- lttng_ht::uptr _channels;
-
- /*
- * Unique key to identify the metadata on the consumer side.
- */
- uint64_t _metadata_key = 0;
- /*
- * Indicates if the metadata is closed on the consumer side. This is to
- * avoid double close of metadata when an application unregisters AND
- * deletes its sessions.
- */
- bool _metadata_closed = false;
-
- /* User and group owning the session. */
- uid_t _uid = -1;
- gid_t _gid = -1;
-
- /* Enumerations table. */
- lttng_ht::uptr _enums;
-
- /*
- * Copy of the tracer version when the first app is registered.
- * It is used if we need to regenerate the metadata.
- */
- uint32_t _app_tracer_version_major = 0;
- uint32_t _app_tracer_version_minor = 0;
-
- /* The id of the parent session */
- uint64_t _tracing_id = -1ULL;
-};