include/lttng/snapshot.h

   1 /*
   2  * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #ifndef LTTNG_SNAPSHOT_H
   9 #define LTTNG_SNAPSHOT_H
  10
  11 #include <limits.h>
  12 #include <stdint.h>
  13 #include <sys/types.h>
  14
  15 #ifdef __cplusplus
  16 extern "C" {
  17 #endif
  18
  19 /*
  20  * Snapshot output object is opaque to the user. Use the helper functions below
  21  * to use them.
  22  */
  23 struct lttng_snapshot_output;
  24 struct lttng_snapshot_output_list;
  25
  26 /*
  27  * Return an newly allocated snapshot output object or NULL on error.
  28  */
  29 struct lttng_snapshot_output *lttng_snapshot_output_create(void);
  30
  31 /*
  32  * Free a given snapshot output object.
  33  */
  34 void lttng_snapshot_output_destroy(struct lttng_snapshot_output *output);
  35
  36 /*
  37  * Snapshot output getter family functions. They all return the value present
  38  * in the object.
  39  */
  40
  41 /* Return snapshot ID. */
  42 uint32_t lttng_snapshot_output_get_id(struct lttng_snapshot_output *output);
  43 /* Return maximum size of a snapshot. */
  44 uint64_t lttng_snapshot_output_get_maxsize(struct lttng_snapshot_output *output);
  45 /* Return snapshot name. */
  46 const char *lttng_snapshot_output_get_name(struct lttng_snapshot_output *output);
  47 /* Return snapshot control URL in a text format. */
  48 const char *lttng_snapshot_output_get_ctrl_url(struct lttng_snapshot_output *output);
  49 /* Return snapshot data URL in a text format. */
  50 const char *lttng_snapshot_output_get_data_url(struct lttng_snapshot_output *output);
  51
  52 /*
  53  * Snapshot output setter family functions.
  54  *
  55  * For every set* call, 0 is returned on success or else -LTTNG_ERR_INVALID is
  56  * returned indicating that at least one given parameter is invalid.
  57  */
  58
  59 /* Set a custom ID. */
  60 int lttng_snapshot_output_set_id(uint32_t id,
  61                 struct lttng_snapshot_output *output);
  62 /* Set the maximum size. */
  63 int lttng_snapshot_output_set_size(uint64_t size,
  64                 struct lttng_snapshot_output *output);
  65 /* Set the snapshot name. */
  66 int lttng_snapshot_output_set_name(const char *name,
  67                 struct lttng_snapshot_output *output);
  68 /* Set the control URL. Local and remote URL are supported. */
  69 int lttng_snapshot_output_set_ctrl_url(const char *url,
  70                 struct lttng_snapshot_output *output);
  71 /* Set the data URL. Local and remote URL are supported. */
  72 int lttng_snapshot_output_set_data_url(const char *url,
  73                 struct lttng_snapshot_output *output);
  74
  75 /*
  76  * Add an output object to a session identified by name.
  77  *
  78  * Return 0 on success or else a negative LTTNG_ERR code.
  79  */
  80 int lttng_snapshot_add_output(const char *session_name,
  81                 struct lttng_snapshot_output *output);
  82
  83 /*
  84  * Delete an output object to a session identified by name.
  85  *
  86  * Return 0 on success or else a negative LTTNG_ERR code.
  87  */
  88 int lttng_snapshot_del_output(const char *session_name,
  89                 struct lttng_snapshot_output *output);
  90
  91 /*
  92  * List all snapshot output(s) of a session identified by name. The output list
  93  * object is populated and can be iterated over with the get_next call below.
  94  *
  95  * Return 0 on success or else a negative LTTNG_ERR code and the list pointer
  96  * is untouched.
  97  */
  98 int lttng_snapshot_list_output(const char *session_name,
  99                 struct lttng_snapshot_output_list **list);
 100
 101 /*
 102  * Return the next available snapshot output object in the given list. A list
 103  * output command MUST have been done before.
 104  *
 105  * Return the next object on success or else NULL indicating the end of the
 106  * list.
 107  */
 108 struct lttng_snapshot_output *lttng_snapshot_output_list_get_next(
 109                 struct lttng_snapshot_output_list *list);
 110
 111 /*
 112  * Free an output list object.
 113  */
 114 void lttng_snapshot_output_list_destroy(struct lttng_snapshot_output_list *list);
 115
 116 /*
 117  * Snapshot a trace for the given session.
 118  *
 119  * The output object can be NULL but an add output MUST be done prior to this
 120  * call. If it's not NULL, it will be used to snapshot a trace.
 121  *
 122  * The wait parameter is ignored for now. The snapshot record command will
 123  * ALWAYS wait for the snapshot to complete before returning meaning the
 124  * snapshot has been written on disk or streamed over the network to a relayd.
 125  *
 126  * Return 0 on success or else a negative LTTNG_ERR value.
 127  */
 128 int lttng_snapshot_record(const char *session_name,
 129                 struct lttng_snapshot_output *output, int wait);
 130
 131 #ifdef __cplusplus
 132 }
 133 #endif
 134
 135 #endif /* LTTNG_SNAPSHOT_H */