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 #ifdef __cplusplus
  20 extern "C" {
  21 #endif
  22
  23 /*
  24  * A trace chunk is a group of directories and files forming a (or a set of)
  25  * complete and independant trace(s). For instance, a trace archive chunk,
  26  * a snapshot, or a regular LTTng trace are all instances of a trace archive.
  27  *
  28  * A trace chunk is always contained within a session output directory.
  29  *
  30  * This facility is used by the session daemon, consumer daemon(s), and relay
  31  * daemon to:
  32  *   - Control file (data stream, metadata, and index) creation relative to
  33  *     a given output directory,
  34  *   - Track the use of an output directory by other objects in order to
  35  *     know if/when an output directory can be safely consumed, renamed,
  36  *     deleted, etc.
  37  *
  38  *
  39  * OWNER VS USER
  40  * ---
  41  *
  42  * A trace chunk can either be a owner or a user of its
  43  * "chunk output directory".
  44  *
  45  * A "user" trace chunk is provided with a handle to the chunk output directory
  46  * which can then be used to create subdirectories and files.
  47  *
  48  * An "owner" chunk, on top of being able to perform the operations of a "user"
  49  * chunk can perform operations on its chunk output directory, such as renaming
  50  * or deleting it.
  51  *
  52  * A trace chunk becomes an "owner" or "user" chunk based on which of
  53  * 'lttng_trace_chunk_set_as_owner()' or 'lttng_trace_chunk_set_as_user()' is
  54  * used. These methods are _exclusive_ and must only be used once on a
  55  * trace chunk.
  56  */
  57
  58 struct lttng_trace_chunk;
  59 struct fd_tracker;
  60
  61 enum lttng_trace_chunk_status {
  62         LTTNG_TRACE_CHUNK_STATUS_OK,
  63         LTTNG_TRACE_CHUNK_STATUS_NONE,
  64         LTTNG_TRACE_CHUNK_STATUS_INVALID_ARGUMENT,
  65         LTTNG_TRACE_CHUNK_STATUS_INVALID_OPERATION,
  66         LTTNG_TRACE_CHUNK_STATUS_ERROR,
  67         LTTNG_TRACE_CHUNK_STATUS_NO_FILE,
  68 };
  69
  70 enum lttng_trace_chunk_command_type {
  71         LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED = 0,
  72         LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION = 1,
  73         LTTNG_TRACE_CHUNK_COMMAND_TYPE_DELETE = 2,
  74         LTTNG_TRACE_CHUNK_COMMAND_TYPE_MAX,
  75 };
  76
  77 struct lttng_trace_chunk *lttng_trace_chunk_create_anonymous(void);
  78
  79 struct lttng_trace_chunk *lttng_trace_chunk_create(
  80                 uint64_t chunk_id,
  81                 time_t chunk_creation_time,
  82                 const char *path);
  83
  84 void lttng_trace_chunk_set_fd_tracker(struct lttng_trace_chunk *chunk,
  85                 struct fd_tracker *fd_tracker);
  86
  87 /*
  88  * Copy a trace chunk. The copy that is returned is always a _user_
  89  * mode chunk even if the source chunk was an _owner_ as there can never be
  90  * two _owners_ of the same trace output.
  91  */
  92 struct lttng_trace_chunk *lttng_trace_chunk_copy(
  93                 struct lttng_trace_chunk *source_chunk);
  94
  95 enum lttng_trace_chunk_status lttng_trace_chunk_get_id(
  96                 struct lttng_trace_chunk *chunk, uint64_t *id);
  97
  98 enum lttng_trace_chunk_status lttng_trace_chunk_get_creation_timestamp(
  99                 struct lttng_trace_chunk *chunk, time_t *creation_ts);
 100
 101 enum lttng_trace_chunk_status lttng_trace_chunk_get_close_timestamp(
 102                 struct lttng_trace_chunk *chunk, time_t *close_ts);
 103
 104 enum lttng_trace_chunk_status lttng_trace_chunk_set_close_timestamp(
 105                 struct lttng_trace_chunk *chunk, time_t close_ts);
 106
 107 enum lttng_trace_chunk_status lttng_trace_chunk_get_name(
 108                 struct lttng_trace_chunk *chunk, const char **name,
 109                 bool *name_overridden);
 110
 111 bool lttng_trace_chunk_get_name_overridden(struct lttng_trace_chunk *chunk);
 112
 113 enum lttng_trace_chunk_status lttng_trace_chunk_override_name(
 114                 struct lttng_trace_chunk *chunk, const char *name);
 115
 116 enum lttng_trace_chunk_status lttng_trace_chunk_rename_path(
 117                 struct lttng_trace_chunk *chunk, const char *path);
 118
 119 enum lttng_trace_chunk_status lttng_trace_chunk_get_credentials(
 120                 struct lttng_trace_chunk *chunk,
 121                 struct lttng_credentials *credentials);
 122
 123 enum lttng_trace_chunk_status lttng_trace_chunk_set_credentials(
 124                 struct lttng_trace_chunk *chunk,
 125                 const struct lttng_credentials *credentials);
 126
 127 enum lttng_trace_chunk_status lttng_trace_chunk_set_credentials_current_user(
 128                 struct lttng_trace_chunk *chunk);
 129
 130 enum lttng_trace_chunk_status lttng_trace_chunk_set_as_owner(
 131                 struct lttng_trace_chunk *chunk,
 132                 struct lttng_directory_handle *session_output_directory);
 133
 134 enum lttng_trace_chunk_status lttng_trace_chunk_set_as_user(
 135                 struct lttng_trace_chunk *chunk,
 136                 struct lttng_directory_handle *chunk_directory);
 137
 138 enum lttng_trace_chunk_status
 139 lttng_trace_chunk_get_session_output_directory_handle(
 140                 struct lttng_trace_chunk *chunk,
 141                 struct lttng_directory_handle **handle);
 142
 143 enum lttng_trace_chunk_status lttng_trace_chunk_borrow_chunk_directory_handle(
 144                 struct lttng_trace_chunk *chunk,
 145                 const struct lttng_directory_handle **handle);
 146
 147 enum lttng_trace_chunk_status lttng_trace_chunk_create_subdirectory(
 148                 struct lttng_trace_chunk *chunk,
 149                 const char *subdirectory_path);
 150
 151 enum lttng_trace_chunk_status lttng_trace_chunk_open_file(
 152                 struct lttng_trace_chunk *chunk,
 153                 const char *filename,
 154                 int flags,
 155                 mode_t mode,
 156                 int *out_fd,
 157                 bool expect_no_file);
 158
 159 enum lttng_trace_chunk_status lttng_trace_chunk_open_fs_handle(
 160                 struct lttng_trace_chunk *chunk,
 161                 const char *filename,
 162                 int flags,
 163                 mode_t mode,
 164                 struct fs_handle **out_handle,
 165                 bool expect_no_file);
 166
 167 int lttng_trace_chunk_unlink_file(struct lttng_trace_chunk *chunk,
 168                 const char *filename);
 169
 170 enum lttng_trace_chunk_status lttng_trace_chunk_get_close_command(
 171                 struct lttng_trace_chunk *chunk,
 172                 enum lttng_trace_chunk_command_type *command_type);
 173
 174 enum lttng_trace_chunk_status lttng_trace_chunk_set_close_command(
 175                 struct lttng_trace_chunk *chunk,
 176                 enum lttng_trace_chunk_command_type command_type);
 177
 178 const char *lttng_trace_chunk_command_type_get_name(
 179                 enum lttng_trace_chunk_command_type command);
 180
 181 bool lttng_trace_chunk_ids_equal(const struct lttng_trace_chunk *chunk_a,
 182                 const struct lttng_trace_chunk *chunk_b);
 183
 184 /* Returns true on success. */
 185 bool lttng_trace_chunk_get(struct lttng_trace_chunk *chunk);
 186
 187 void lttng_trace_chunk_put(struct lttng_trace_chunk *chunk);
 188
 189 #ifdef __cplusplus
 190 }
 191 #endif
 192
 193 #endif /* LTTNG_TRACE_CHUNK_H */