src/common/trace-chunk.h

   1 /*
   2  * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #ifndef LTTNG_TRACE_CHUNK_H
   9 #define LTTNG_TRACE_CHUNK_H
  10
  11 #include <common/compat/directory-handle.h>
  12 #include <common/credentials.h>
  13 #include <common/fd-tracker/fd-tracker.h>
  14 #include <common/macros.h>
  15 #include <stdbool.h>
  16 #include <stddef.h>
  17 #include <stdint.h>
  18
  19 /*
  20  * A trace chunk is a group of directories and files forming a (or a set of)
  21  * complete and independant trace(s). For instance, a trace archive chunk,
  22  * a snapshot, or a regular LTTng trace are all instances of a trace archive.
  23  *
  24  * A trace chunk is always contained within a session output directory.
  25  *
  26  * This facility is used by the session daemon, consumer daemon(s), and relay
  27  * daemon to:
  28  *   - Control file (data stream, metadata, and index) creation relative to
  29  *     a given output directory,
  30  *   - Track the use of an output directory by other objects in order to
  31  *     know if/when an output directory can be safely consumed, renamed,
  32  *     deleted, etc.
  33  *
  34  *
  35  * OWNER VS USER
  36  * ---
  37  *
  38  * A trace chunk can either be a owner or a user of its
  39  * "chunk output directory".
  40  *
  41  * A "user" trace chunk is provided with a handle to the chunk output directory
  42  * which can then be used to create subdirectories and files.
  43  *
  44  * An "owner" chunk, on top of being able to perform the operations of a "user"
  45  * chunk can perform operations on its chunk output directory, such as renaming
  46  * or deleting it.
  47  *
  48  * A trace chunk becomes an "owner" or "user" chunk based on which of
  49  * 'lttng_trace_chunk_set_as_owner()' or 'lttng_trace_chunk_set_as_user()' is
  50  * used. These methods are _exclusive_ and must only be used once on a
  51  * trace chunk.
  52  */
  53
  54 struct lttng_trace_chunk;
  55 struct fd_tracker;
  56
  57 enum lttng_trace_chunk_status {
  58         LTTNG_TRACE_CHUNK_STATUS_OK,
  59         LTTNG_TRACE_CHUNK_STATUS_NONE,
  60         LTTNG_TRACE_CHUNK_STATUS_INVALID_ARGUMENT,
  61         LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION,
  62         LTTNG_TRACE_CHUNK_STATUS_ERROR,
  63         LTTNG_TRACE_CHUNK_STATUS_NO_FILE,
  64 };
  65
  66 enum lttng_trace_chunk_command_type {
  67         LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED = 0,
  68         LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION = 1,
  69         LTTNG_TRACE_CHUNK_COMMAND_TYPE_DELETE = 2,
  70         LTTNG_TRACE_CHUNK_COMMAND_TYPE_MAX,
  71 };
  72
  73 struct lttng_trace_chunk *lttng_trace_chunk_create_anonymous(void);
  74
  75 struct lttng_trace_chunk *lttng_trace_chunk_create(
  76                 uint64_t chunk_id,
  77                 time_t chunk_creation_time,
  78                 const char *path);
  79
  80 void lttng_trace_chunk_set_fd_tracker(struct lttng_trace_chunk *chunk,
  81                 struct fd_tracker *fd_tracker);
  82
  83 /*
  84  * Copy a trace chunk. The copy that is returned is always a _user_
  85  * mode chunk even if the source chunk was an _owner_ as there can never be
  86  * two _owners_ of the same trace output.
  87  */
  88 struct lttng_trace_chunk *lttng_trace_chunk_copy(
  89                 struct lttng_trace_chunk *source_chunk);
  90
  91 enum lttng_trace_chunk_status lttng_trace_chunk_get_id(
  92                 struct lttng_trace_chunk *chunk, uint64_t *id);
  93
  94 enum lttng_trace_chunk_status lttng_trace_chunk_get_creation_timestamp(
  95                 struct lttng_trace_chunk *chunk, time_t *creation_ts);
  96
  97 enum lttng_trace_chunk_status lttng_trace_chunk_get_close_timestamp(
  98                 struct lttng_trace_chunk *chunk, time_t *close_ts);
  99
 100 enum lttng_trace_chunk_status lttng_trace_chunk_set_close_timestamp(
 101                 struct lttng_trace_chunk *chunk, time_t close_ts);
 102
 103 enum lttng_trace_chunk_status lttng_trace_chunk_get_name(
 104                 struct lttng_trace_chunk *chunk, const char **name,
 105                 bool *name_overridden);
 106
 107 bool lttng_trace_chunk_get_name_overridden(struct lttng_trace_chunk *chunk);
 108
 109 enum lttng_trace_chunk_status lttng_trace_chunk_override_name(
 110                 struct lttng_trace_chunk *chunk, const char *name);
 111
 112 enum lttng_trace_chunk_status lttng_trace_chunk_rename_path(
 113                 struct lttng_trace_chunk *chunk, const char *path);
 114
 115 enum lttng_trace_chunk_status lttng_trace_chunk_get_credentials(
 116                 struct lttng_trace_chunk *chunk,
 117                 struct lttng_credentials *credentials);
 118
 119 enum lttng_trace_chunk_status lttng_trace_chunk_set_credentials(
 120                 struct lttng_trace_chunk *chunk,
 121                 const struct lttng_credentials *credentials);
 122
 123 enum lttng_trace_chunk_status lttng_trace_chunk_set_credentials_current_user(
 124                 struct lttng_trace_chunk *chunk);
 125
 126 enum lttng_trace_chunk_status lttng_trace_chunk_set_as_owner(
 127                 struct lttng_trace_chunk *chunk,
 128                 struct lttng_directory_handle *session_output_directory);
 129
 130 enum lttng_trace_chunk_status lttng_trace_chunk_set_as_user(
 131                 struct lttng_trace_chunk *chunk,
 132                 struct lttng_directory_handle *chunk_directory);
 133
 134 enum lttng_trace_chunk_status
 135 lttng_trace_chunk_get_session_output_directory_handle(
 136                 struct lttng_trace_chunk *chunk,
 137                 struct lttng_directory_handle **handle);
 138
 139 enum lttng_trace_chunk_status lttng_trace_chunk_borrow_chunk_directory_handle(
 140                 struct lttng_trace_chunk *chunk,
 141                 const struct lttng_directory_handle **handle);
 142
 143 enum lttng_trace_chunk_status lttng_trace_chunk_create_subdirectory(
 144                 struct lttng_trace_chunk *chunk,
 145                 const char *subdirectory_path);
 146
 147 enum lttng_trace_chunk_status lttng_trace_chunk_open_file(
 148                 struct lttng_trace_chunk *chunk,
 149                 const char *filename,
 150                 int flags,
 151                 mode_t mode,
 152                 int *out_fd,
 153                 bool expect_no_file);
 154
 155 enum lttng_trace_chunk_status lttng_trace_chunk_open_fs_handle(
 156                 struct lttng_trace_chunk *chunk,
 157                 const char *filename,
 158                 int flags,
 159                 mode_t mode,
 160                 struct fs_handle **out_handle,
 161                 bool expect_no_file);
 162
 163 int lttng_trace_chunk_unlink_file(struct lttng_trace_chunk *chunk,
 164                 const char *filename);
 165
 166 enum lttng_trace_chunk_status lttng_trace_chunk_get_close_command(
 167                 struct lttng_trace_chunk *chunk,
 168                 enum lttng_trace_chunk_command_type *command_type);
 169
 170 enum lttng_trace_chunk_status lttng_trace_chunk_set_close_command(
 171                 struct lttng_trace_chunk *chunk,
 172                 enum lttng_trace_chunk_command_type command_type);
 173
 174 const char *lttng_trace_chunk_command_type_get_name(
 175                 enum lttng_trace_chunk_command_type command);
 176
 177 bool lttng_trace_chunk_ids_equal(const struct lttng_trace_chunk *chunk_a,
 178                 const struct lttng_trace_chunk *chunk_b);
 179
 180 /* Returns true on success. */
 181 bool lttng_trace_chunk_get(struct lttng_trace_chunk *chunk);
 182
 183 void lttng_trace_chunk_put(struct lttng_trace_chunk *chunk);
 184
 185 #endif /* LTTNG_TRACE_CHUNK_H */