lib/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, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   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 Unsigned integer field instance indicating the
 120  *        sequence's length.
 121  *
 122  * Returns 0 on success, a negative value on error.
 123  */
 124 extern int bt_ctf_field_sequence_set_length(struct bt_ctf_field *sequence,
 125                 struct bt_ctf_field *length_field);
 126
 127 /*
 128  * bt_ctf_field_sequence_get_field: get a sequence's field at position "index".
 129  *
 130  * Return the sequence's field at position "index". The sequence's length must
 131  * have been set prior to calling this function using
 132  * bt_ctf_field_sequence_set_length().
 133  * bt_ctf_field_put() must be called on the returned value.
 134  *
 135  * @param array Sequence field instance.
 136  * @param index Position of the sequence's desired element.
 137  *
 138  * Returns a field instance on success, NULL on error.
 139  */
 140 extern struct bt_ctf_field *bt_ctf_field_sequence_get_field(
 141                 struct bt_ctf_field *sequence, uint64_t index);
 142
 143 /*
 144  * bt_ctf_field_variant_get_field: get a variant's selected field.
 145  *
 146  * Return the variant's selected field. The "tag" field is the selector enum
 147  * field. bt_ctf_field_put() must be called on the returned value.
 148  *
 149  * @param variant Variant field instance.
 150  * @param tag Selector enumeration field.
 151  *
 152  * Returns a field instance on success, NULL on error.
 153  */
 154 extern struct bt_ctf_field *bt_ctf_field_variant_get_field(
 155                 struct bt_ctf_field *variant, struct bt_ctf_field *tag);
 156
 157 /*
 158  * bt_ctf_field_enumeration_get_container: get an enumeration field's container.
 159  *
 160  * Return the enumeration's underlying container field (an integer).
 161  * bt_ctf_field_put() must be called on the returned value.
 162  *
 163  * @param enumeration Enumeration field instance.
 164  *
 165  * Returns a field instance on success, NULL on error.
 166  */
 167 extern struct bt_ctf_field *bt_ctf_field_enumeration_get_container(
 168                 struct bt_ctf_field *enumeration);
 169
 170 /*
 171  * bt_ctf_field_enumeration_get_mapping_name: get an enumeration field's mapping
 172  *      name.
 173  *
 174  * Return the enumeration's underlying container field (an integer).
 175  * bt_ctf_field_put() must be called on the returned value.
 176  *
 177  * @param enumeration Enumeration field instance.
 178  *
 179  * Returns a field instance on success, NULL on error.
 180  */
 181 extern const char *bt_ctf_field_enumeration_get_mapping_name(
 182                 struct bt_ctf_field *enumeration);
 183
 184 /*
 185  * bt_ctf_field_signed_integer_get_value: get a signed integer field's value
 186  *
 187  * Get a signed integer field's value.
 188  *
 189  * @param integer Signed integer field instance.
 190  * @param value Pointer to a signed integer where the value will be stored.
 191  *
 192  * Returns 0 on success, a negative value on error.
 193  */
 194 extern int bt_ctf_field_signed_integer_get_value(struct bt_ctf_field *integer,
 195                 int64_t *value);
 196
 197 /*
 198  * bt_ctf_field_signed_integer_set_value: set a signed integer field's value
 199  *
 200  * Set a signed integer field's value. The value is checked to make sure it
 201  * can be stored in the underlying field.
 202  *
 203  * @param integer Signed integer field instance.
 204  * @param value Signed integer field value.
 205  *
 206  * Returns 0 on success, a negative value on error.
 207  */
 208 extern int bt_ctf_field_signed_integer_set_value(struct bt_ctf_field *integer,
 209                 int64_t value);
 210
 211 /*
 212  * bt_ctf_field_unsigned_integer_get_value: get unsigned integer field's value
 213  *
 214  * Get an unsigned integer field's value.
 215  *
 216  * @param integer Unsigned integer field instance.
 217  * @param value Pointer to an unsigned integer where the value will be stored.
 218  *
 219  * Returns 0 on success, a negative value on error.
 220  */
 221 extern int bt_ctf_field_unsigned_integer_get_value(struct bt_ctf_field *integer,
 222                 uint64_t *value);
 223
 224 /*
 225  * bt_ctf_field_unsigned_integer_set_value: set unsigned integer field's value
 226  *
 227  * Set an unsigned integer field's value. The value is checked to make sure it
 228  * can be stored in the underlying field.
 229  *
 230  * @param integer Unsigned integer field instance.
 231  * @param value Unsigned integer field value.
 232  *
 233  * Returns 0 on success, a negative value on error.
 234  */
 235 extern int bt_ctf_field_unsigned_integer_set_value(struct bt_ctf_field *integer,
 236                 uint64_t value);
 237
 238 /*
 239  * bt_ctf_field_floating_point_get_value: get a floating point field's value
 240  *
 241  * Get a floating point field's value.
 242  *
 243  * @param floating_point Floating point field instance.
 244  * @param value Pointer to a double where the value will be stored.
 245  *
 246  * Returns 0 on success, a negative value on error.
 247  */
 248 extern int bt_ctf_field_floating_point_get_value(
 249                 struct bt_ctf_field *floating_point, double *value);
 250
 251 /*
 252  * bt_ctf_field_floating_point_set_value: set a floating point field's value
 253  *
 254  * Set a floating point field's value. The underlying type may not support the
 255  * double's full precision.
 256  *
 257  * @param floating_point Floating point field instance.
 258  * @param value Floating point field value.
 259  *
 260  * Returns 0 on success, a negative value on error.
 261  */
 262 extern int bt_ctf_field_floating_point_set_value(
 263                 struct bt_ctf_field *floating_point,
 264                 double value);
 265
 266 /*
 267  * bt_ctf_field_string_get_value: get a string field's value
 268  *
 269  * Get a string field's value.
 270  *
 271  * @param string_field String field instance.
 272  *
 273  * Returns the string's value, NULL if unset.
 274  */
 275 extern const char *bt_ctf_field_string_get_value(
 276                 struct bt_ctf_field *string_field);
 277
 278 /*
 279  * bt_ctf_field_string_set_value: set a string field's value
 280  *
 281  * Set a string field's value.
 282  *
 283  * @param string_field String field instance.
 284  * @param value String field value (will be copied).
 285  *
 286  * Returns 0 on success, a negative value on error.
 287  */
 288 extern int bt_ctf_field_string_set_value(struct bt_ctf_field *string_field,
 289                 const char *value);
 290
 291 /*
 292  * bt_ctf_field_get_type: get a field's type
 293  *
 294  * @param field Field intance.
 295  *
 296  * Returns a field type instance on success, NULL on error.
 297  */
 298 extern struct bt_ctf_field_type *bt_ctf_field_get_type(
 299                 struct bt_ctf_field *field);
 300
 301 /*
 302  * bt_ctf_field_get and bt_ctf_field_put: increment and decrement the
 303  * field's reference count.
 304  *
 305  * These functions ensure that the field won't be destroyed when it
 306  * is in use. The same number of get and put (plus one extra put to
 307  * release the initial reference done at creation) have to be done to
 308  * destroy a field.
 309  *
 310  * When the field's reference count is decremented to 0 by a bt_ctf_field_put,
 311  * the field is freed.
 312  *
 313  * @param field Field instance.
 314  */
 315 extern void bt_ctf_field_get(struct bt_ctf_field *field);
 316 extern void bt_ctf_field_put(struct bt_ctf_field *field);
 317
 318 #ifdef __cplusplus
 319 }
 320 #endif
 321
 322 #endif /* BABELTRACE_CTF_IR_EVENT_FIELDS_H */