include/lttng/rotation.h

   1 /*
   2  * Copyright (C) 2017 - Julien Desfossez <jdesfossez@efficios.com>
   3  * Copyright (C) 2018 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  *
   5  * This library is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU Lesser General Public License, version 2.1 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This library is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
  12  * for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public License
  15  * along with this library; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #ifndef LTTNG_ROTATION_H
  20 #define LTTNG_ROTATION_H
  21
  22 #include <stdint.h>
  23 #include <lttng/location.h>
  24
  25 #ifdef __cplusplus
  26 extern "C" {
  27 #endif
  28
  29 /*
  30  * Return codes for lttng_rotation_handle_get_state()
  31  */
  32 enum lttng_rotation_state {
  33         /*
  34          * Session has not been rotated.
  35          */
  36         LTTNG_ROTATION_STATE_NO_ROTATION = 0,
  37         /*
  38          * Rotation is ongoing, but has not been completed yet.
  39          */
  40         LTTNG_ROTATION_STATE_ONGOING = 1,
  41         /*
  42          * Rotation has been completed and the resulting chunk
  43          * can now safely be read.
  44          */
  45         LTTNG_ROTATION_STATE_COMPLETED = 2,
  46         /*
  47          * The rotation has expired.
  48          *
  49          * The information associated with a given rotation is eventually
  50          * purged by the session daemon. In such a case, the attributes of
  51          * the rotation, such as its path, may no longer be available.
  52          *
  53          * Note that this state does not guarantee the the rotation was
  54          * completed successfully.
  55          */
  56         LTTNG_ROTATION_STATE_EXPIRED = 3,
  57         /*
  58          * The rotation could not be completed due to an error.
  59          */
  60         LTTNG_ROTATION_STATE_ERROR = 4,
  61 };
  62
  63 enum lttng_rotation_status {
  64         LTTNG_ROTATION_STATUS_OK = 0,
  65         /* Information not available. */
  66         LTTNG_ROTATION_STATUS_UNAVAILABLE = 1,
  67         /* Generic error. */
  68         LTTNG_ROTATION_STATUS_ERROR = -1,
  69         /* Invalid parameters provided. */
  70         LTTNG_ROTATION_STATUS_INVALID = -2,
  71 };
  72
  73 /*
  74  * Input parameter to the lttng_rotate_session command.
  75  *
  76  * An immediate rotation is performed as soon as possible by the tracers.
  77  */
  78 struct lttng_rotation_immediate_attr;
  79
  80 /*
  81  * Input parameter to the lttng_rotate_schedule command.
  82  */
  83 struct lttng_rotation_schedule_attr;
  84
  85 /*
  86  * Handle used to represent a specific rotation.
  87  */
  88 struct lttng_rotation_handle;
  89
  90 /*
  91  * Return a newly allocated session rotation schedule descriptor object or NULL
  92  * on error.
  93  *
  94  * The rotation schedule may be expressed as a size or as a time period.
  95  */
  96 extern struct lttng_rotation_schedule_attr *
  97 lttng_rotation_schedule_attr_create(void);
  98
  99 /*
 100  * Destroy a given scheduled rotate session descriptor object.
 101  */
 102 extern void lttng_rotation_schedule_attr_destroy(
 103                 struct lttng_rotation_schedule_attr *attr);
 104
 105 /*
 106  * Set the timer to periodically rotate the session (in µs).
 107  */
 108 extern enum lttng_rotation_status lttng_rotation_schedule_attr_set_timer_period(
 109                 struct lttng_rotation_schedule_attr *attr, uint64_t timer);
 110
 111 /*
 112  * Set the size to rotate the session (in bytes).
 113  */
 114 void lttng_rotation_schedule_attr_set_size(
 115                 struct lttng_rotation_schedule_attr *attr, uint64_t size);
 116
 117 /*
 118  * lttng rotate session handle functions.
 119  */
 120
 121 /*
 122  * Get the current state of the rotation referenced by the handle.
 123  *
 124  * This will issue a request to the session daemon on every call. Hence,
 125  * the result of this call may change over time.
 126  */
 127 extern enum lttng_rotation_status lttng_rotation_handle_get_state(
 128                 struct lttng_rotation_handle *rotation_handle,
 129                 enum lttng_rotation_state *rotation_state);
 130
 131 /*
 132  * Get the location of the rotation's resulting archive.
 133  *
 134  * The rotation must be completed in order for this call to succeed.
 135  * The location returned remains owned by the rotation handle.
 136  *
 137  * Note that location will not be set in case of error, or if the session
 138  * rotation handle has expired.
 139  */
 140 extern enum lttng_rotation_status lttng_rotation_handle_get_archive_location(
 141                 struct lttng_rotation_handle *rotation_handle,
 142                 const struct lttng_trace_archive_location **location);
 143
 144 /*
 145  * Destroy an lttng_rotate_session handle.
 146  */
 147 extern void lttng_rotation_handle_destroy(
 148                 struct lttng_rotation_handle *rotation_handle);
 149
 150 /*
 151  * Rotate the output folder of the session.
 152  *
 153  * On success, handle is allocated and can be used to monitor the progress
 154  * of the rotation with lttng_rotation_get_state(). The handle must be freed
 155  * by the caller with lttng_rotation_handle_destroy().
 156  *
 157  * Passing NULL as the immediate rotation attribute results in the default
 158  * options being used.
 159  *
 160  * Return 0 if the rotate action was successfully launched or a negative
 161  * LTTng error code on error.
 162  */
 163 extern int lttng_rotate_session(const char *session_name,
 164                 struct lttng_rotation_immediate_attr *attr,
 165                 struct lttng_rotation_handle **rotation_handle);
 166
 167 /*
 168  * Configure a session to rotate according to a given schedule.
 169  */
 170 extern int lttng_rotation_set_schedule(const char *session_name,
 171                 struct lttng_rotation_schedule_attr *attr);
 172
 173 /*
 174  * Ask the sessiond for the value of the rotate timer (in micro-seconds) of the
 175  * session.
 176  *
 177  * On success, return 0 and set the value or rotate_timer, on error return a
 178  * negative value.
 179  */
 180 extern int lttng_rotation_schedule_get_timer_period(const char *session_name,
 181                 uint64_t *rotate_timer);
 182
 183 /*
 184  * Ask the sessiond for the value of the rotate size (in micro-seconds) of the
 185  * session.
 186  *
 187  * On success, return 0 and set the value or rotate_size, on error return
 188  * a negative value.
 189  */
 190 extern int lttng_rotation_schedule_get_size(const char *session_name,
 191                 uint64_t *rotate_size);
 192
 193 #ifdef __cplusplus
 194 }
 195 #endif
 196
 197 #endif /* LTTNG_ROTATION_H */