src/common/trace-chunk.hpp

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