src/lib/trace-ir/utils.h

   1 #ifndef BABELTRACE_TRACE_IR_UTILS_INTERNAL_H
   2 #define BABELTRACE_TRACE_IR_UTILS_INTERNAL_H
   3
   4 /*
   5  * Copyright 2017-2018 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  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE.
  24  */
  25
  26 #include "common/macros.h"
  27 #include <babeltrace2/trace-ir/field-class.h>
  28 #include <stdbool.h>
  29 #include <stdint.h>
  30
  31 #include "clock-class.h"
  32
  33 struct search_query {
  34         gpointer value;
  35         int found;
  36 };
  37
  38 static inline
  39 uint64_t bt_util_ns_from_value(uint64_t frequency, uint64_t value_cycles)
  40 {
  41         uint64_t ns;
  42
  43         if (frequency == UINT64_C(1000000000)) {
  44                 ns = value_cycles;
  45         } else {
  46                 double dblres = ((1e9 * (double) value_cycles) / (double) frequency);
  47
  48                 if (dblres >= (double) UINT64_MAX) {
  49                         /* Overflows uint64_t */
  50                         ns = UINT64_C(-1);
  51                 } else {
  52                         ns = (uint64_t) dblres;
  53                 }
  54         }
  55
  56         return ns;
  57 }
  58
  59 static inline
  60 bool bt_util_get_base_offset_ns(int64_t offset_seconds, uint64_t offset_cycles,
  61                 uint64_t frequency, int64_t *base_offset_ns)
  62 {
  63         bool overflows = false;
  64         uint64_t offset_cycles_ns;
  65
  66         BT_ASSERT_DBG(base_offset_ns);
  67
  68         /* Initialize nanosecond timestamp to clock's offset in seconds */
  69         if (offset_seconds <= (INT64_MIN / INT64_C(1000000000) - 1) ||
  70                         offset_seconds >= (INT64_MAX / INT64_C(1000000000)) - 1) {
  71                 /*
  72                  * Overflow: offset in seconds converted to nanoseconds
  73                  * is outside the int64_t range. We also subtract 1 here
  74                  * to leave "space" for the offset in cycles converted
  75                  * to nanoseconds (which is always less than 1 second by
  76                  * contract).
  77                  */
  78                 overflows = true;
  79                 goto end;
  80         }
  81
  82         /* Offset (seconds) to nanoseconds */
  83         *base_offset_ns = offset_seconds * INT64_C(1000000000);
  84
  85         /* Add offset in cycles */
  86         BT_ASSERT_DBG(offset_cycles < frequency);
  87         offset_cycles_ns = bt_util_ns_from_value(frequency,
  88                 offset_cycles);
  89         BT_ASSERT_DBG(offset_cycles_ns < 1000000000);
  90         *base_offset_ns += (int64_t) offset_cycles_ns;
  91
  92 end:
  93         return overflows;
  94 }
  95
  96 static inline
  97 int bt_util_ns_from_origin_inline(int64_t base_offset_ns,
  98                 int64_t offset_seconds, uint64_t offset_cycles,
  99                 uint64_t frequency, uint64_t value, int64_t *ns_from_origin)
 100 {
 101         int ret = 0;
 102         uint64_t value_ns_unsigned;
 103         int64_t value_ns_signed;
 104
 105         /* Initialize to clock class's base offset */
 106         *ns_from_origin = base_offset_ns;
 107
 108         /* Add given value in cycles */
 109         value_ns_unsigned = bt_util_ns_from_value(frequency, value);
 110         if (value_ns_unsigned >= (uint64_t) INT64_MAX) {
 111                 /*
 112                  * FIXME: `value_ns_unsigned` could be greater than
 113                  * `INT64_MAX` in fact: in this case, we need to
 114                  * subtract `INT64_MAX` from `value_ns_unsigned`, make
 115                  * sure that the difference is less than `INT64_MAX`,
 116                  * and try to add them one after the other to
 117                  * `*ns_from_origin`.
 118                  */
 119                 ret = -1;
 120                 goto end;
 121         }
 122
 123         value_ns_signed = (int64_t) value_ns_unsigned;
 124         BT_ASSERT_DBG(value_ns_signed >= 0);
 125
 126         if (*ns_from_origin <= 0) {
 127                 goto add_value;
 128         }
 129
 130         if (value_ns_signed > INT64_MAX - *ns_from_origin) {
 131                 ret = -1;
 132                 goto end;
 133         }
 134
 135 add_value:
 136         *ns_from_origin += value_ns_signed;
 137
 138 end:
 139         return ret;
 140 }
 141
 142 static inline
 143 int bt_util_ns_from_origin_clock_class(const struct bt_clock_class *clock_class,
 144                 uint64_t value, int64_t *ns_from_origin)
 145 {
 146         int ret = 0;
 147
 148         if (clock_class->base_offset.overflows) {
 149                 ret = -1;
 150                 goto end;
 151         }
 152
 153         ret = bt_util_ns_from_origin_inline(clock_class->base_offset.value_ns,
 154                 clock_class->offset_seconds, clock_class->offset_cycles,
 155                 clock_class->frequency, value, ns_from_origin);
 156
 157 end:
 158         return ret;
 159 }
 160
 161 static inline
 162 bool bt_util_value_is_in_range_signed(uint64_t size, int64_t value)
 163 {
 164         int64_t min_value = UINT64_C(-1) << (size - 1);
 165         int64_t max_value = (UINT64_C(1) << (size - 1)) - 1;
 166         return value >= min_value && value <= max_value;
 167 }
 168
 169 static inline
 170 bool bt_util_value_is_in_range_unsigned(unsigned int size, uint64_t value)
 171 {
 172         uint64_t max_value = (size == 64) ? UINT64_MAX :
 173                 (UINT64_C(1) << size) - 1;
 174         return value <= max_value;
 175 }
 176
 177 #endif /* BABELTRACE_TRACE_IR_UTILS_INTERNAL_H */