src/plugins/ctf/common/metadata/decoder.h

   1 #ifndef _METADATA_DECODER_H
   2 #define _METADATA_DECODER_H
   3
   4 /*
   5  * Copyright 2016-2017 - Philippe Proulx <pproulx@efficios.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  */
  17
  18 #include <stdint.h>
  19 #include <stdbool.h>
  20
  21 #include <babeltrace2/babeltrace.h>
  22
  23 #include "common/macros.h"
  24 #include "common/uuid.h"
  25
  26 struct ctf_trace_class;
  27
  28 /* A CTF metadata decoder object */
  29 struct ctf_metadata_decoder;
  30
  31 /* CTF metadata decoder status */
  32 enum ctf_metadata_decoder_status {
  33         CTF_METADATA_DECODER_STATUS_OK                  = 0,
  34         CTF_METADATA_DECODER_STATUS_NONE                = 1,
  35         CTF_METADATA_DECODER_STATUS_ERROR               = -1,
  36         CTF_METADATA_DECODER_STATUS_INCOMPLETE          = -2,
  37         CTF_METADATA_DECODER_STATUS_INVAL_VERSION       = -3,
  38         CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR    = -4,
  39 };
  40
  41 /* Decoding configuration */
  42 struct ctf_metadata_decoder_config {
  43         /* Active log level to use */
  44         bt_logging_level log_level;
  45
  46         /* Component to use for logging (can be `NULL`); weak */
  47         bt_self_component *self_comp;
  48
  49         /* Additional clock class offset to apply */
  50         int64_t clock_class_offset_s;
  51         int64_t clock_class_offset_ns;
  52
  53         /* True to create trace class objects */
  54         bool create_trace_class;
  55
  56         /*
  57          * True to keep the plain text when content is appended with
  58          * ctf_metadata_decoder_append_content().
  59          */
  60         bool keep_plain_text;
  61 };
  62
  63 /*
  64  * Creates a CTF metadata decoder.
  65  *
  66  * Returns `NULL` on error.
  67  */
  68 BT_HIDDEN
  69 struct ctf_metadata_decoder *ctf_metadata_decoder_create(
  70                 const struct ctf_metadata_decoder_config *config);
  71
  72 /*
  73  * Destroys a CTF metadata decoder that you created with
  74  * ctf_metadata_decoder_create().
  75  */
  76 BT_HIDDEN
  77 void ctf_metadata_decoder_destroy(
  78                 struct ctf_metadata_decoder *metadata_decoder);
  79
  80 /*
  81  * Appends content to the metadata decoder.
  82  *
  83  * This function reads the metadata from the current position of `fp`
  84  * until the end of this file stream.
  85  *
  86  * The metadata can be packetized or not.
  87  *
  88  * The metadata chunk needs to be complete and lexically scannable, that
  89  * is, zero or more complete top-level blocks. If it's incomplete, this
  90  * function returns `CTF_METADATA_DECODER_STATUS_INCOMPLETE`. If this
  91  * function returns `CTF_METADATA_DECODER_STATUS_INCOMPLETE`, then you
  92  * need to call it again with the _same_ metadata and more to make it
  93  * complete. For example:
  94  *
  95  *     First call:  event { name = hell
  96  *     Second call: event { name = hello_world; ... };
  97  *
  98  * If everything goes as expected, this function returns
  99  * `CTF_METADATA_DECODER_STATUS_OK`.
 100  */
 101 BT_HIDDEN
 102 enum ctf_metadata_decoder_status ctf_metadata_decoder_append_content(
 103                 struct ctf_metadata_decoder *metadata_decoder, FILE *fp);
 104
 105 /*
 106  * Returns the trace IR trace class of this metadata decoder (new
 107  * reference).
 108  *
 109  * Returns `NULL` if there's none yet or if the metadata decoder is not
 110  * configured to create trace classes.
 111  */
 112 BT_HIDDEN
 113 bt_trace_class *ctf_metadata_decoder_get_ir_trace_class(
 114                 struct ctf_metadata_decoder *mdec);
 115
 116 /*
 117  * Returns the CTF IR trace class of this metadata decoder.
 118  *
 119  * Returns `NULL` if there's none yet or if the metadata decoder is not
 120  * configured to create trace classes.
 121  */
 122 BT_HIDDEN
 123 struct ctf_trace_class *ctf_metadata_decoder_borrow_ctf_trace_class(
 124                 struct ctf_metadata_decoder *mdec);
 125
 126 /*
 127  * Checks whether or not a given metadata file stream `fp` is
 128  * packetized, setting `is_packetized` accordingly on success. On
 129  * success, also sets `*byte_order` to the byte order of the first
 130  * packet.
 131  *
 132  * This function uses `log_level` and `self_comp` for logging purposes.
 133  * `self_comp` can be `NULL` if not available.
 134  */
 135 BT_HIDDEN
 136 int ctf_metadata_decoder_is_packetized(FILE *fp, bool *is_packetized,
 137                 int *byte_order, bt_logging_level log_level,
 138                 bt_self_component *self_comp);
 139
 140 /*
 141  * Returns the byte order of the decoder's metadata stream as set by the
 142  * last call to ctf_metadata_decoder_append_content().
 143  *
 144  * Returns -1 if unknown (plain text content).
 145  */
 146 BT_HIDDEN
 147 int ctf_metadata_decoder_get_byte_order(struct ctf_metadata_decoder *mdec);
 148
 149 /*
 150  * Returns the UUID of the decoder's metadata stream as set by the last
 151  * call to ctf_metadata_decoder_append_content().
 152  */
 153 BT_HIDDEN
 154 int ctf_metadata_decoder_get_uuid(
 155                 struct ctf_metadata_decoder *mdec, bt_uuid_t uuid);
 156
 157 /*
 158  * Returns the UUID of the decoder's trace class, if available.
 159  *
 160  * Returns:
 161  *
 162  * * `CTF_METADATA_DECODER_STATUS_OK`: success.
 163  * * `CTF_METADATA_DECODER_STATUS_NONE`: no UUID.
 164  * * `CTF_METADATA_DECODER_STATUS_INCOMPLETE`: missing metadata content.
 165  */
 166 BT_HIDDEN
 167 enum ctf_metadata_decoder_status ctf_metadata_decoder_get_trace_class_uuid(
 168                 struct ctf_metadata_decoder *mdec, bt_uuid_t uuid);
 169
 170 /*
 171  * Returns the metadata decoder's current metadata text.
 172  */
 173 BT_HIDDEN
 174 const char *ctf_metadata_decoder_get_text(struct ctf_metadata_decoder *mdec);
 175
 176 static inline
 177 bool ctf_metadata_decoder_is_packet_version_valid(unsigned int major,
 178                 unsigned int minor)
 179 {
 180         return major == 1 && minor == 8;
 181 }
 182
 183 #endif /* _METADATA_DECODER_H */