lib/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  *
 143  * Returns the clock's offset in seconds, -1ULL on error.
 144  */
 145 extern uint64_t bt_ctf_clock_get_offset_s(struct bt_ctf_clock *clock);
 146
 147 /*
 148  * bt_ctf_clock_set_offset_s: set a clock's offset in seconds.
 149  *
 150  * Set the clock's offset in seconds from POSIX.1 Epoch, 1970-01-01,
 151  * defaults to 0.
 152  *
 153  * @param clock Clock instance.
 154  * @param offset_s Clock's offset in seconds, defaults to 0.
 155  *
 156  * Returns 0 on success, a negative value on error.
 157  */
 158 extern int bt_ctf_clock_set_offset_s(struct bt_ctf_clock *clock,
 159                 uint64_t offset_s);
 160
 161 /*
 162  * bt_ctf_clock_get_offset_s: get a clock's offset in ticks.
 163  *
 164  * Get the clock's offset in ticks from Epoch + offset_t.
 165  *
 166  * @param clock Clock instance.
 167  *
 168  * Returns the clock's offset in ticks from Epoch + offset_s, -1ULL on error.
 169  */
 170 extern uint64_t bt_ctf_clock_get_offset(struct bt_ctf_clock *clock);
 171
 172 /*
 173  * bt_ctf_clock_set_offset: set a clock's offset in ticks.
 174  *
 175  * Set the clock's offset in ticks from Epoch + offset_s.
 176  *
 177  * @param clock Clock instance.
 178  * @param offset Clock's offset in ticks from Epoch + offset_s, defaults to 0.
 179  *
 180  * Returns 0 on success, a negative value on error.
 181  */
 182 extern int bt_ctf_clock_set_offset(struct bt_ctf_clock *clock,
 183                 uint64_t offset);
 184
 185 /*
 186  * bt_ctf_clock_get_is_absolute: get a clock's absolute attribute.
 187  *
 188  * Get the clock's absolute attribute. A clock is absolute if the clock is a
 189  * global reference across the trace's other clocks.
 190  *
 191  * @param clock Clock instance.
 192  *
 193  * Returns the clock's absolute attribute, a negative value on error.
 194  */
 195 extern int bt_ctf_clock_get_is_absolute(struct bt_ctf_clock *clock);
 196
 197 /*
 198  * bt_ctf_clock_set_is_absolute: set a clock's absolute attribute.
 199  *
 200  * Set the clock's absolute attribute. A clock is absolute if the clock is a
 201  * global reference across the trace's other clocks.
 202  *
 203  * @param clock Clock instance.
 204  * @param is_absolute Clock's absolute attribute, defaults to FALSE.
 205  *
 206  * Returns 0 on success, a negative value on error.
 207  */
 208 extern int bt_ctf_clock_set_is_absolute(struct bt_ctf_clock *clock,
 209                 int is_absolute);
 210
 211 /*
 212  * bt_ctf_clock_get_time: get a clock's current time value.
 213  *
 214  * Get the current time in nanoseconds since the clock's origin (offset and
 215  * offset_s attributes).
 216  *
 217  * Returns the clock's current time value, -1ULL on error.
 218  */
 219 extern uint64_t bt_ctf_clock_get_time(struct bt_ctf_clock *clock);
 220
 221 /*
 222  * bt_ctf_clock_set_time: set a clock's current time value.
 223  *
 224  * Set the current time in nanoseconds since the clock's origin (offset and
 225  * offset_s attributes). Defaults to 0.
 226  *
 227  * Returns 0 on success, a negative value on error.
 228  */
 229 extern int bt_ctf_clock_set_time(struct bt_ctf_clock *clock,
 230                 uint64_t time);
 231
 232 /*
 233  * bt_ctf_clock_get and bt_ctf_clock_put: increment and decrement the
 234  * refcount of the clock
 235  *
 236  * These functions ensure that the clock won't be destroyed when it
 237  * is in use. The same number of get and put (plus one extra put to
 238  * release the initial reference done at creation) has to be done to
 239  * destroy a clock.
 240  *
 241  * When the clock refcount is decremented to 0 by a bt_ctf_clock_put,
 242  * the clock is freed.
 243  *
 244  * @param clock Clock instance.
 245  */
 246 extern void bt_ctf_clock_get(struct bt_ctf_clock *clock);
 247 extern void bt_ctf_clock_put(struct bt_ctf_clock *clock);
 248
 249 #ifdef __cplusplus
 250 }
 251 #endif
 252
 253 #endif /* BABELTRACE_CTF_IR_CLOCK_H */