include/babeltrace/ctf-ir/clock.h

   1 #ifndef BABELTRACE_CTF_IR_CLOCK_H
   2 #define BABELTRACE_CTF_IR_CLOCK_H
   3
   4 /*
   5  * BabelTrace - CTF IR: Clock
   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
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 struct bt_ctf_clock;
  40
  41 /*
  42  * bt_ctf_clock_create: create a clock.
  43  *
  44  * Allocate a new clock setting its reference count to 1.
  45  *
  46  * @param name Name of the clock (will be copied).
  47  *
  48  * Returns an allocated clock on success, NULL on error.
  49  */
  50 extern struct bt_ctf_clock *bt_ctf_clock_create(const char *name);
  51
  52 /*
  53  * bt_ctf_clock_get_name: get a clock's name.
  54  *
  55  * Get the clock's name.
  56  *
  57  * @param clock Clock instance.
  58  *
  59  * Returns the clock's name, NULL on error.
  60  */
  61 extern const char *bt_ctf_clock_get_name(struct bt_ctf_clock *clock);
  62
  63 /*
  64  * bt_ctf_clock_get_description: get a clock's description.
  65  *
  66  * Get the clock's description.
  67  *
  68  * @param clock Clock instance.
  69  *
  70  * Returns the clock's description, NULL if unset.
  71  */
  72 extern const char *bt_ctf_clock_get_description(struct bt_ctf_clock *clock);
  73
  74 /*
  75  * bt_ctf_clock_set_description: set a clock's description.
  76  *
  77  * Set the clock's description. The description appears in the clock's TSDL
  78  * meta-data.
  79  *
  80  * @param clock Clock instance.
  81  * @param desc Description of the clock.
  82  *
  83  * Returns 0 on success, a negative value on error.
  84  */
  85 extern int bt_ctf_clock_set_description(struct bt_ctf_clock *clock,
  86                 const char *desc);
  87
  88 /*
  89  * bt_ctf_clock_get_frequency: get a clock's frequency.
  90  *
  91  * Get the clock's frequency (Hz).
  92  *
  93  * @param clock Clock instance.
  94  *
  95  * Returns the clock's frequency, -1ULL on error.
  96  */
  97 extern uint64_t bt_ctf_clock_get_frequency(struct bt_ctf_clock *clock);
  98
  99 /*
 100  * bt_ctf_clock_set_frequency: set a clock's frequency.
 101  *
 102  * Set the clock's frequency (Hz).
 103  *
 104  * @param clock Clock instance.
 105  * @param freq Clock's frequency in Hz, defaults to 1 000 000 000 Hz (1ns).
 106  *
 107  * Returns 0 on success, a negative value on error.
 108  */
 109 extern int bt_ctf_clock_set_frequency(struct bt_ctf_clock *clock,
 110                 uint64_t freq);
 111
 112 /*
 113  * bt_ctf_clock_get_precision: get a clock's precision.
 114  *
 115  * Get the clock's precision (in clock ticks).
 116  *
 117  * @param clock Clock instance.
 118  *
 119  * Returns the clock's precision, -1ULL on error.
 120  */
 121 extern uint64_t bt_ctf_clock_get_precision(struct bt_ctf_clock *clock);
 122
 123 /*
 124  * bt_ctf_clock_set_precision: set a clock's precision.
 125  *
 126  * Set the clock's precision.
 127  *
 128  * @param clock Clock instance.
 129  * @param precision Clock's precision in clock ticks, defaults to 1.
 130  *
 131  * Returns 0 on success, a negative value on error.
 132  */
 133 extern int bt_ctf_clock_set_precision(struct bt_ctf_clock *clock,
 134                 uint64_t precision);
 135
 136 /*
 137  * bt_ctf_clock_get_offset_s: get a clock's offset in seconds.
 138  *
 139  * Get the clock's offset in seconds from POSIX.1 Epoch, 1970-01-01.
 140  *
 141  * @param clock Clock instance.
 142  * @param offset_s Pointer to clock offset in seconds (output).
 143  *
 144  * Returns 0 on success, a negative value on error.
 145  */
 146 extern int bt_ctf_clock_get_offset_s(struct bt_ctf_clock *clock,
 147                 int64_t *offset_s);
 148
 149 /*
 150  * bt_ctf_clock_set_offset_s: set a clock's offset in seconds.
 151  *
 152  * Set the clock's offset in seconds from POSIX.1 Epoch, 1970-01-01,
 153  * defaults to 0.
 154  *
 155  * @param clock Clock instance.
 156  * @param offset_s Clock's offset in seconds, defaults to 0.
 157  *
 158  * Returns 0 on success, a negative value on error.
 159  */
 160 extern int bt_ctf_clock_set_offset_s(struct bt_ctf_clock *clock,
 161                 int64_t offset_s);
 162
 163 /*
 164  * bt_ctf_clock_get_offset: get a clock's offset in ticks.
 165  *
 166  * Get the clock's offset in ticks from Epoch + offset_t.
 167  *
 168  * @param clock Clock instance.
 169  * @param offset Clock offset in ticks from Epoch + offset_s (output).
 170  *
 171  * Returns 0 on success, a negative value on error.
 172  */
 173 extern int bt_ctf_clock_get_offset(struct bt_ctf_clock *clock,
 174                 int64_t *offset);
 175
 176 /*
 177  * bt_ctf_clock_set_offset: set a clock's offset in ticks.
 178  *
 179  * Set the clock's offset in ticks from Epoch + offset_s.
 180  *
 181  * @param clock Clock instance.
 182  * @param offset Clock's offset in ticks from Epoch + offset_s, defaults to 0.
 183  *
 184  * Returns 0 on success, a negative value on error.
 185  */
 186 extern int bt_ctf_clock_set_offset(struct bt_ctf_clock *clock,
 187                 int64_t offset);
 188
 189 /*
 190  * bt_ctf_clock_get_is_absolute: get a clock's absolute attribute.
 191  *
 192  * Get the clock's absolute attribute. A clock is absolute if the clock is a
 193  * global reference across the trace's other clocks.
 194  *
 195  * @param clock Clock instance.
 196  *
 197  * Returns the clock's absolute attribute, a negative value on error.
 198  */
 199 extern int bt_ctf_clock_get_is_absolute(struct bt_ctf_clock *clock);
 200
 201 /*
 202  * bt_ctf_clock_set_is_absolute: set a clock's absolute attribute.
 203  *
 204  * Set the clock's absolute attribute. A clock is absolute if the clock is a
 205  * global reference across the trace's other clocks.
 206  *
 207  * @param clock Clock instance.
 208  * @param is_absolute Clock's absolute attribute, defaults to FALSE.
 209  *
 210  * Returns 0 on success, a negative value on error.
 211  */
 212 extern int bt_ctf_clock_set_is_absolute(struct bt_ctf_clock *clock,
 213                 int is_absolute);
 214
 215 /*
 216  * bt_ctf_clock_get_uuid: get a clock's UUID.
 217  *
 218  * Get the clock's UUID.
 219  *
 220  * @param clock Clock instance.
 221  *
 222  * Returns a pointer to the clock's UUID (16 byte array) on success,
 223  * NULL on error.
 224  */
 225 extern const unsigned char *bt_ctf_clock_get_uuid(struct bt_ctf_clock *clock);
 226
 227 /*
 228  * bt_ctf_clock_set_uuid: set a clock's UUID.
 229  *
 230  * Set a clock's UUID.
 231  *
 232  * @param clock Clock instance.
 233  * @param uuid A 16-byte array containing a UUID.
 234  *
 235  * Returns 0 on success, a negative value on error.
 236  */
 237 extern int bt_ctf_clock_set_uuid(struct bt_ctf_clock *clock,
 238                 const unsigned char *uuid);
 239
 240 /*
 241  * bt_ctf_clock_get_time: get a clock's current time value.
 242  *
 243  * Get the current time in nanoseconds since the clock's origin (offset and
 244  * offset_s attributes).
 245  *
 246  * @param clock Clock instance.
 247  * @param time Clock current time value (output).
 248  *
 249  * Returns 0 on success, a negative value on error.
 250  */
 251 extern int bt_ctf_clock_get_time(struct bt_ctf_clock *clock,
 252                 int64_t *time);
 253
 254 /*
 255  * bt_ctf_clock_set_time: set a clock's current time value.
 256  *
 257  * Set the current time in nanoseconds since the clock's origin (offset and
 258  * offset_s attributes). Defaults to 0.
 259  *
 260  * Returns 0 on success, a negative value on error.
 261  */
 262 extern int bt_ctf_clock_set_time(struct bt_ctf_clock *clock,
 263                 int64_t time);
 264
 265 /*
 266  * bt_ctf_clock_get and bt_ctf_clock_put: increment and decrement the
 267  * refcount of the clock
 268  *
 269  * You may also use bt_ctf_get() and bt_ctf_put() with clock objects.
 270  *
 271  * These functions ensure that the clock won't be destroyed when it
 272  * is in use. The same number of get and put (plus one extra put to
 273  * release the initial reference done at creation) has to be done to
 274  * destroy a clock.
 275  *
 276  * When the clock refcount is decremented to 0 by a bt_ctf_clock_put,
 277  * the clock is freed.
 278  *
 279  * @param clock Clock instance.
 280  */
 281 extern void bt_ctf_clock_get(struct bt_ctf_clock *clock);
 282 extern void bt_ctf_clock_put(struct bt_ctf_clock *clock);
 283
 284 #ifdef __cplusplus
 285 }
 286 #endif
 287
 288 #endif /* BABELTRACE_CTF_IR_CLOCK_H */