include/lttng/trigger/trigger-internal.h

   1 /*
   2  * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #ifndef LTTNG_TRIGGER_INTERNAL_H
   9 #define LTTNG_TRIGGER_INTERNAL_H
  10
  11 #include <lttng/trigger/trigger.h>
  12 #include <common/credentials.h>
  13 #include <common/dynamic-array.h>
  14 #include <common/macros.h>
  15 #include <common/optional.h>
  16 #include <stdint.h>
  17 #include <stdbool.h>
  18 #include <sys/types.h>
  19 #include <urcu/ref.h>
  20
  21 struct lttng_payload;
  22 struct lttng_payload_view;
  23
  24 struct lttng_trigger {
  25         /* Reference counting is only exposed to internal users. */
  26         struct urcu_ref ref;
  27
  28         struct lttng_condition *condition;
  29         struct lttng_action *action;
  30         char *name;
  31         /* For now only the uid portion of the credentials is used. */
  32         struct lttng_credentials creds;
  33         struct {
  34                 enum lttng_trigger_firing_policy type;
  35                 uint64_t threshold;
  36                 uint64_t current_count;
  37         } firing_policy;
  38         /*
  39          * Internal use only.
  40          * The unique token passed to the tracer to identify an event-rule
  41          * notification.
  42          */
  43         LTTNG_OPTIONAL(uint64_t) tracer_token;
  44 };
  45
  46 struct lttng_triggers {
  47         struct lttng_dynamic_pointer_array array;
  48 };
  49
  50 struct lttng_trigger_comm {
  51         /*
  52          * Credentials, only the uid portion is used for now.
  53          * Used as an override when desired by the root user.
  54          */
  55         uint64_t uid;
  56         /*
  57          * Length of the variable length payload (name, condition, and
  58          * an action).
  59          */
  60         uint32_t length;
  61         /* Includes '\0' terminator. */
  62         uint32_t name_length;
  63         /* Firing policy. */
  64         /* Maps to enum lttng_trigger_firing_policy. */
  65         uint8_t firing_policy_type;
  66         uint64_t firing_policy_threshold;
  67         /* A null-terminated name, a condition, and an action follow. */
  68         char payload[];
  69 } LTTNG_PACKED;
  70
  71 struct lttng_triggers_comm {
  72         uint32_t count;
  73         uint32_t length;
  74         /* Count * lttng_trigger_comm structure */
  75         char payload[];
  76 };
  77
  78 LTTNG_HIDDEN
  79 ssize_t lttng_trigger_create_from_payload(struct lttng_payload_view *view,
  80                 struct lttng_trigger **trigger);
  81
  82 LTTNG_HIDDEN
  83 int lttng_trigger_serialize(const struct lttng_trigger *trigger,
  84                 struct lttng_payload *payload);
  85
  86 LTTNG_HIDDEN
  87 bool lttng_trigger_validate(const struct lttng_trigger *trigger);
  88
  89 LTTNG_HIDDEN
  90 int lttng_trigger_assign_name(
  91                 struct lttng_trigger *dst, const struct lttng_trigger *src);
  92
  93 LTTNG_HIDDEN
  94 void lttng_trigger_set_tracer_token(
  95                 struct lttng_trigger *trigger, uint64_t token);
  96
  97 LTTNG_HIDDEN
  98 uint64_t lttng_trigger_get_tracer_token(const struct lttng_trigger *trigger);
  99
 100 LTTNG_HIDDEN
 101 int lttng_trigger_generate_name(struct lttng_trigger *trigger,
 102                 uint64_t unique_id);
 103
 104 LTTNG_HIDDEN
 105 bool lttng_trigger_is_equal(
 106                 const struct lttng_trigger *a, const struct lttng_trigger *b);
 107
 108 LTTNG_HIDDEN
 109 void lttng_trigger_get(struct lttng_trigger *trigger);
 110
 111 LTTNG_HIDDEN
 112 void lttng_trigger_put(struct lttng_trigger *trigger);
 113
 114 /*
 115  * Allocate a new set of triggers.
 116  * The returned object must be freed via lttng_triggers_destroy.
 117  */
 118 LTTNG_HIDDEN
 119 struct lttng_triggers *lttng_triggers_create(void);
 120
 121 /*
 122  * Return the a pointer to a mutable element at index "index" of an
 123  * lttng_triggers set.
 124  *
 125  * This differs from the public `lttng_triggers_get_at_index` in that
 126  * the returned pointer to a mutable trigger.
 127  *
 128  * The ownership of the trigger set element is NOT transfered.
 129  * The returned object can NOT be freed via lttng_trigger_destroy.
 130  */
 131 LTTNG_HIDDEN
 132 struct lttng_trigger *lttng_triggers_borrow_mutable_at_index(
 133                 const struct lttng_triggers *triggers, unsigned int index);
 134
 135 /*
 136  * Add a trigger to the triggers set.
 137  *
 138  * A reference to the added trigger is acquired on behalf of the trigger set
 139  * on success.
 140  */
 141 LTTNG_HIDDEN
 142 int lttng_triggers_add(
 143                 struct lttng_triggers *triggers, struct lttng_trigger *trigger);
 144
 145 /*
 146  * Serialize a trigger set to an lttng_payload object.
 147  * Return LTTNG_OK on success, negative lttng error code on error.
 148  */
 149 LTTNG_HIDDEN
 150 int lttng_triggers_serialize(const struct lttng_triggers *triggers,
 151                 struct lttng_payload *payload);
 152
 153 LTTNG_HIDDEN
 154 ssize_t lttng_triggers_create_from_payload(struct lttng_payload_view *view,
 155                 struct lttng_triggers **triggers);
 156
 157 LTTNG_HIDDEN
 158 const struct lttng_credentials *lttng_trigger_get_credentials(
 159                 const struct lttng_trigger *trigger);
 160
 161 LTTNG_HIDDEN
 162 void lttng_trigger_set_credentials(struct lttng_trigger *trigger,
 163                 const struct lttng_credentials *creds);
 164
 165
 166 /*
 167  * Fire the trigger.
 168  * Increments the occurrence count.
 169  */
 170 LTTNG_HIDDEN
 171 void lttng_trigger_fire(struct lttng_trigger *trigger);
 172
 173 /*
 174  * Check if the trigger would fire.
 175  */
 176 LTTNG_HIDDEN
 177 bool lttng_trigger_should_fire(const struct lttng_trigger *trigger);
 178
 179 /*
 180  * Return the type of any underlying domain restriction. If no particular
 181  * requirement is present, returns LTTNG_DOMAIN_NONE.
 182  */
 183 LTTNG_HIDDEN
 184 enum lttng_domain_type lttng_trigger_get_underlying_domain_type_restriction(
 185                 const struct lttng_trigger *trigger);
 186
 187 /*
 188  * Generate any bytecode related to the trigger.
 189  * On success LTTNG_OK. On error, returns lttng_error code.
 190  */
 191 LTTNG_HIDDEN
 192 enum lttng_error_code lttng_trigger_generate_bytecode(
 193                 struct lttng_trigger *trigger,
 194                 const struct lttng_credentials *creds);
 195
 196 LTTNG_HIDDEN
 197 struct lttng_trigger *lttng_trigger_copy(const struct lttng_trigger *trigger);
 198
 199 #endif /* LTTNG_TRIGGER_INTERNAL_H */