include/babeltrace/ctf-ir/event-fields.h

   1 #ifndef BABELTRACE_CTF_IR_EVENT_FIELDS_H
   2 #define BABELTRACE_CTF_IR_EVENT_FIELDS_H
   3
   4 /*
   5  * BabelTrace - CTF IR: Event Fields
   6  *
   7  * Copyright 2013 EfficiOS Inc.
   8  *
   9  * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  27  * SOFTWARE.
  28  *
  29  * The Common Trace Format (CTF) Specification is available at
  30  * http://www.efficios.com/ctf
  31  */
  32
  33 #include <stdint.h>
  34 #include <stddef.h>
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 struct bt_ctf_event_class;
  41 struct bt_ctf_event;
  42 struct bt_ctf_field;
  43 struct bt_ctf_field_type;
  44
  45 /*
  46  * bt_ctf_field_create: create an instance of a field.
  47  *
  48  * Allocate a new field of the type described by the bt_ctf_field_type
  49  * structure.The creation of a field sets its reference count to 1.
  50  *
  51  * @param type Field type to be instanciated.
  52  *
  53  * Returns an allocated field on success, NULL on error.
  54  */
  55 extern struct bt_ctf_field *bt_ctf_field_create(
  56                 struct bt_ctf_field_type *type);
  57
  58 /*
  59  * bt_ctf_field_structure_get_field: get a structure's field.
  60  *
  61  * Get the structure's field corresponding to the provided field name.
  62  * bt_ctf_field_put() must be called on the returned value.
  63  *
  64  * @param structure Structure field instance.
  65  * @param name Name of the field in the provided structure.
  66  *
  67  * Returns a field instance on success, NULL on error.
  68  */
  69 extern struct bt_ctf_field *bt_ctf_field_structure_get_field(
  70                 struct bt_ctf_field *structure, const char *name);
  71
  72 /*
  73  * bt_ctf_field_structure_get_field_by_index: get a structure's field by index.
  74  *
  75  * Get the structure's field corresponding to the provided field name.
  76  * bt_ctf_field_put() must be called on the returned value.
  77  * The indexes are the same as those provided for bt_ctf_field_type_structure.
  78  *
  79  * @param structure Structure field instance.
  80  * @param index Index of the field in the provided structure.
  81  *
  82  * Returns a field instance on success, NULL on error.
  83  */
  84 extern struct bt_ctf_field *bt_ctf_field_structure_get_field_by_index(
  85                 struct bt_ctf_field *structure, size_t index);
  86
  87 /*
  88  * bt_ctf_field_array_get_field: get an array's field at position "index".
  89  *
  90  * Return the array's field at position "index". bt_ctf_field_put() must be
  91  * called on the returned value.
  92  *
  93  * @param array Array field instance.
  94  * @param index Position of the array's desired element.
  95  *
  96  * Returns a field instance on success, NULL on error.
  97  */
  98 extern struct bt_ctf_field *bt_ctf_field_array_get_field(
  99                 struct bt_ctf_field *array, uint64_t index);
 100
 101 /*
 102  * bt_ctf_field_sequence_get_length: get a sequence's length.
 103  *
 104  * Get the sequence's length field.
 105  *
 106  * @param sequence Sequence field instance.
 107  *
 108  * Returns a field instance on success, NULL if a length was never set.
 109  */
 110 extern struct bt_ctf_field *bt_ctf_field_sequence_get_length(
 111                 struct bt_ctf_field *sequence);
 112
 113 /*
 114  * bt_ctf_field_sequence_set_length: set a sequence's length.
 115  *
 116  * Set the sequence's length field.
 117  *
 118  * @param sequence Sequence field instance.
 119  * @param length_field Integer field instance indicating the sequence's length.
 120  *
 121  * Returns 0 on success, a negative value on error.
 122  */
 123 extern int bt_ctf_field_sequence_set_length(struct bt_ctf_field *sequence,
 124                 struct bt_ctf_field *length_field);
 125
 126 /*
 127  * bt_ctf_field_sequence_get_field: get a sequence's field at position "index".
 128  *
 129  * Return the sequence's field at position "index". The sequence's length must
 130  * have been set prior to calling this function using
 131  * bt_ctf_field_sequence_set_length().
 132  * bt_ctf_field_put() must be called on the returned value.
 133  *
 134  * @param array Sequence field instance.
 135  * @param index Position of the sequence's desired element.
 136  *
 137  * Returns a field instance on success, NULL on error.
 138  */
 139 extern struct bt_ctf_field *bt_ctf_field_sequence_get_field(
 140                 struct bt_ctf_field *sequence, uint64_t index);
 141
 142 /*
 143  * bt_ctf_field_variant_get_field: get a variant's selected field.
 144  *
 145  * Return the variant's selected field. The "tag" field is the selector enum
 146  * field. bt_ctf_field_put() must be called on the returned value.
 147  *
 148  * @param variant Variant field instance.
 149  * @param tag Selector enumeration field.
 150  *
 151  * Returns a field instance on success, NULL on error.
 152  */
 153 extern struct bt_ctf_field *bt_ctf_field_variant_get_field(
 154                 struct bt_ctf_field *variant, struct bt_ctf_field *tag);
 155
 156 /*
 157  * bt_ctf_field_enumeration_get_container: get an enumeration field's container.
 158  *
 159  * Return the enumeration's underlying container field (an integer).
 160  * bt_ctf_field_put() must be called on the returned value.
 161  *
 162  * @param enumeration Enumeration field instance.
 163  *
 164  * Returns a field instance on success, NULL on error.
 165  */
 166 extern struct bt_ctf_field *bt_ctf_field_enumeration_get_container(
 167                 struct bt_ctf_field *enumeration);
 168
 169 /*
 170  * bt_ctf_field_enumeration_get_mapping_name: get an enumeration field's mapping
 171  *      name.
 172  *
 173  * Return the enumeration's underlying container field (an integer).
 174  * bt_ctf_field_put() must be called on the returned value.
 175  *
 176  * @param enumeration Enumeration field instance.
 177  *
 178  * Returns a field instance on success, NULL on error.
 179  */
 180 extern const char *bt_ctf_field_enumeration_get_mapping_name(
 181                 struct bt_ctf_field *enumeration);
 182
 183 /*
 184  * bt_ctf_field_signed_integer_get_value: get a signed integer field's value
 185  *
 186  * Get a signed integer field's value.
 187  *
 188  * @param integer Signed integer field instance.
 189  * @param value Pointer to a signed integer where the value will be stored.
 190  *
 191  * Returns 0 on success, a negative value on error.
 192  */
 193 extern int bt_ctf_field_signed_integer_get_value(struct bt_ctf_field *integer,
 194                 int64_t *value);
 195
 196 /*
 197  * bt_ctf_field_signed_integer_set_value: set a signed integer field's value
 198  *
 199  * Set a signed integer field's value. The value is checked to make sure it
 200  * can be stored in the underlying field.
 201  *
 202  * @param integer Signed integer field instance.
 203  * @param value Signed integer field value.
 204  *
 205  * Returns 0 on success, a negative value on error.
 206  */
 207 extern int bt_ctf_field_signed_integer_set_value(struct bt_ctf_field *integer,
 208                 int64_t value);
 209
 210 /*
 211  * bt_ctf_field_unsigned_integer_get_value: get unsigned integer field's value
 212  *
 213  * Get an unsigned integer field's value.
 214  *
 215  * @param integer Unsigned integer field instance.
 216  * @param value Pointer to an unsigned integer where the value will be stored.
 217  *
 218  * Returns 0 on success, a negative value on error.
 219  */
 220 extern int bt_ctf_field_unsigned_integer_get_value(struct bt_ctf_field *integer,
 221                 uint64_t *value);
 222
 223 /*
 224  * bt_ctf_field_unsigned_integer_set_value: set unsigned integer field's value
 225  *
 226  * Set an unsigned integer field's value. The value is checked to make sure it
 227  * can be stored in the underlying field.
 228  *
 229  * @param integer Unsigned integer field instance.
 230  * @param value Unsigned integer field value.
 231  *
 232  * Returns 0 on success, a negative value on error.
 233  */
 234 extern int bt_ctf_field_unsigned_integer_set_value(struct bt_ctf_field *integer,
 235                 uint64_t value);
 236
 237 /*
 238  * bt_ctf_field_floating_point_get_value: get a floating point field's value
 239  *
 240  * Get a floating point field's value.
 241  *
 242  * @param floating_point Floating point field instance.
 243  * @param value Pointer to a double where the value will be stored.
 244  *
 245  * Returns 0 on success, a negative value on error.
 246  */
 247 extern int bt_ctf_field_floating_point_get_value(
 248                 struct bt_ctf_field *floating_point, double *value);
 249
 250 /*
 251  * bt_ctf_field_floating_point_set_value: set a floating point field's value
 252  *
 253  * Set a floating point field's value. The underlying type may not support the
 254  * double's full precision.
 255  *
 256  * @param floating_point Floating point field instance.
 257  * @param value Floating point field value.
 258  *
 259  * Returns 0 on success, a negative value on error.
 260  */
 261 extern int bt_ctf_field_floating_point_set_value(
 262                 struct bt_ctf_field *floating_point,
 263                 double value);
 264
 265 /*
 266  * bt_ctf_field_string_get_value: get a string field's value
 267  *
 268  * Get a string field's value.
 269  *
 270  * @param string_field String field instance.
 271  *
 272  * Returns the string's value, NULL if unset.
 273  */
 274 extern const char *bt_ctf_field_string_get_value(
 275                 struct bt_ctf_field *string_field);
 276
 277 /*
 278  * bt_ctf_field_string_set_value: set a string field's value
 279  *
 280  * Set a string field's value.
 281  *
 282  * @param string_field String field instance.
 283  * @param value String field value (will be copied).
 284  *
 285  * Returns 0 on success, a negative value on error.
 286  */
 287 extern int bt_ctf_field_string_set_value(struct bt_ctf_field *string_field,
 288                 const char *value);
 289
 290 /*
 291  * bt_ctf_field_get_type: get a field's type
 292  *
 293  * @param field Field intance.
 294  *
 295  * Returns a field type instance on success, NULL on error.
 296  */
 297 extern struct bt_ctf_field_type *bt_ctf_field_get_type(
 298                 struct bt_ctf_field *field);
 299
 300 /*
 301  * bt_ctf_field_get and bt_ctf_field_put: increment and decrement the
 302  * field's reference count.
 303  *
 304  * These functions ensure that the field won't be destroyed when it
 305  * is in use. The same number of get and put (plus one extra put to
 306  * release the initial reference done at creation) have to be done to
 307  * destroy a field.
 308  *
 309  * When the field's reference count is decremented to 0 by a bt_ctf_field_put,
 310  * the field is freed.
 311  *
 312  * @param field Field instance.
 313  */
 314 extern void bt_ctf_field_get(struct bt_ctf_field *field);
 315 extern void bt_ctf_field_put(struct bt_ctf_field *field);
 316
 317 #ifdef __cplusplus
 318 }
 319 #endif
 320
 321 #endif /* BABELTRACE_CTF_IR_EVENT_FIELDS_H */