projects / lttng-ust.git / blame
| Commit | Line | Data |
|---|---|---|
| 53569322 | 1 | /* |
| c0c0989a | 2 | * SPDX-License-Identifier: MIT |
| 53569322 | 3 | * |
| c0c0989a | 4 | * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 28b9540b MJ |
5 | * |
| 6 | * The context provider feature is part of the ABI and used by the Java jni | |
| 7 | * interface. This header should be moved to the public header directory once | |
| 8 | * some test code and documentation is written. | |
| 53569322 MD |
9 | */ |
| 10 | ||
| c0c0989a MJ |
11 | #ifndef _LTTNG_UST_CONTEXT_PROVIDER_H |
| 12 | #define _LTTNG_UST_CONTEXT_PROVIDER_H | |
| 13 | ||
| b4051ad8 | 14 | #include <stddef.h> |
| 53569322 | 15 | #include <lttng/ust-events.h> |
| 53569322 | 16 | |
| 9d315d6d | 17 | #include "common/dynamic-type.h" |
| fa194c41 | 18 | |
| 4e48b5d2 | 19 | struct lttng_ust_registered_context_provider; |
| b2e37d27 | 20 | struct lttng_ust_probe_ctx; |
| 4e48b5d2 | 21 | |
| daacdbfc MD |
22 | /* |
| 23 | * Context value | |
| 24 | * | |
| 25 | * IMPORTANT: this structure is part of the ABI between the probe and | |
| 35c1f459 MD |
26 | * UST. Additional selectors may be added in the future, mapping to new |
| 27 | * union fields, which means the overall size of this structure may | |
| 28 | * increase. This means this structure should never be nested within a | |
| 29 | * public structure interface, nor embedded in an array. | |
| daacdbfc MD |
30 | */ |
| 31 | ||
| 32 | struct lttng_ust_ctx_value { | |
| 35c1f459 | 33 | enum lttng_ust_dynamic_type sel; /* Type selector */ |
| fa194c41 MJ |
34 | union { |
| 35 | int64_t s64; | |
| 36 | uint64_t u64; | |
| 37 | const char *str; | |
| 38 | double d; | |
| 39 | } u; | |
| 40 | }; | |
| 41 | ||
| daacdbfc MD |
42 | /* |
| 43 | * Context provider | |
| 44 | * | |
| 45 | * IMPORTANT: this structure is part of the ABI between the probe and | |
| 46 | * UST. Fields need to be only added at the end, never reordered, never | |
| 47 | * removed. | |
| 48 | * | |
| 49 | * The field @struct_size should be used to determine the size of the | |
| 50 | * structure. It should be queried before using additional fields added | |
| 51 | * at the end of the structure. | |
| 52 | */ | |
| 53 | ||
| 53569322 | 54 | struct lttng_ust_context_provider { |
| daacdbfc MD |
55 | uint32_t struct_size; |
| 56 | ||
| 4e48b5d2 | 57 | const char *name; |
| b2e37d27 MD |
58 | size_t (*get_size)(void *priv, struct lttng_ust_probe_ctx *probe_ctx, |
| 59 | size_t offset); | |
| 60 | void (*record)(void *priv, struct lttng_ust_probe_ctx *probe_ctx, | |
| 61 | struct lttng_ust_ring_buffer_ctx *ctx, | |
| 62 | struct lttng_ust_channel_buffer *chan); | |
| 63 | void (*get_value)(void *priv, struct lttng_ust_probe_ctx *probe_ctx, | |
| 64 | struct lttng_ust_ctx_value *value); | |
| 4e48b5d2 | 65 | void *priv; |
| daacdbfc MD |
66 | |
| 67 | /* End of base ABI. Fields below should be used after checking struct_size. */ | |
| 53569322 MD |
68 | }; |
| 69 | ||
| 4e48b5d2 MD |
70 | /* |
| 71 | * Returns an opaque pointer on success, which must be passed to | |
| 72 | * lttng_ust_context_provider_unregister for unregistration. Returns | |
| 73 | * NULL on error. | |
| 74 | */ | |
| 75 | struct lttng_ust_registered_context_provider *lttng_ust_context_provider_register(struct lttng_ust_context_provider *provider); | |
| 53569322 | 76 | |
| 4e48b5d2 | 77 | void lttng_ust_context_provider_unregister(struct lttng_ust_registered_context_provider *reg_provider); |
| 53569322 MD |
78 | |
| 79 | #endif /* _LTTNG_UST_CONTEXT_PROVIDER_H */ |