include/babeltrace/trace-ir/utils-internal.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 <babeltrace/babeltrace-internal.h>
  27 #include <babeltrace/trace-ir/field-class.h>
  28 #include <babeltrace/trace-ir/clock-class-internal.h>
  29 #include <stdint.h>
  30
  31 struct search_query {
  32         gpointer value;
  33         int found;
  34 };
  35
  36 static inline
  37 uint64_t bt_util_ns_from_value(uint64_t frequency, uint64_t value_cycles)
  38 {
  39         uint64_t ns;
  40
  41         if (frequency == UINT64_C(1000000000)) {
  42                 ns = value_cycles;
  43         } else {
  44                 double dblres = ((1e9 * (double) value_cycles) / (double) frequency);
  45
  46                 if (dblres >= (double) UINT64_MAX) {
  47                         /* Overflows uint64_t */
  48                         ns = UINT64_C(-1);
  49                 } else {
  50                         ns = (uint64_t) dblres;
  51                 }
  52         }
  53
  54         return ns;
  55 }
  56
  57 static inline
  58 bool bt_util_get_base_offset_ns(int64_t offset_seconds, uint64_t offset_cycles,
  59                 uint64_t frequency, int64_t *base_offset_ns)
  60 {
  61         bool overflows = false;
  62         uint64_t offset_cycles_ns;
  63
  64         BT_ASSERT(base_offset_ns);
  65
  66         /* Initialize nanosecond timestamp to clock's offset in seconds */
  67         if (offset_seconds <= (INT64_MIN / INT64_C(1000000000) - 1) ||
  68                         offset_seconds >= (INT64_MAX / INT64_C(1000000000)) - 1) {
  69                 /*
  70                  * Overflow: offset in seconds converted to nanoseconds
  71                  * is outside the int64_t range. We also subtract 1 here
  72                  * to leave "space" for the offset in cycles converted
  73                  * to nanoseconds (which is always less than 1 second by
  74                  * contract).
  75                  */
  76                 overflows = true;
  77                 goto end;
  78         }
  79
  80         /* Offset (seconds) to nanoseconds */
  81         *base_offset_ns = offset_seconds * INT64_C(1000000000);
  82
  83         /* Add offset in cycles */
  84         BT_ASSERT(offset_cycles < frequency);
  85         offset_cycles_ns = bt_util_ns_from_value(frequency,
  86                 offset_cycles);
  87         BT_ASSERT(offset_cycles_ns < 1000000000);
  88         *base_offset_ns += (int64_t) offset_cycles_ns;
  89
  90 end:
  91         return overflows;
  92 }
  93
  94 static inline
  95 int bt_util_ns_from_origin_inline(int64_t base_offset_ns,
  96                 int64_t offset_seconds, uint64_t offset_cycles,
  97                 uint64_t frequency, uint64_t value, int64_t *ns_from_origin)
  98 {
  99         int ret = 0;
 100         uint64_t value_ns_unsigned;
 101         int64_t value_ns_signed;
 102
 103         /* Initialize to clock class's base offset */
 104         *ns_from_origin = base_offset_ns;
 105
 106         /* Add given value in cycles */
 107         value_ns_unsigned = bt_util_ns_from_value(frequency, value);
 108         if (value_ns_unsigned >= (uint64_t) INT64_MAX) {
 109                 /*
 110                  * FIXME: `value_ns_unsigned` could be greater than
 111                  * `INT64_MAX` in fact: in this case, we need to
 112                  * subtract `INT64_MAX` from `value_ns_unsigned`, make
 113                  * sure that the difference is less than `INT64_MAX`,
 114                  * and try to add them one after the other to
 115                  * `*ns_from_origin`.
 116                  */
 117                 ret = -1;
 118                 goto end;
 119         }
 120
 121         value_ns_signed = (int64_t) value_ns_unsigned;
 122         BT_ASSERT(value_ns_signed >= 0);
 123
 124         if (*ns_from_origin <= 0) {
 125                 goto add_value;
 126         }
 127
 128         if (value_ns_signed > INT64_MAX - *ns_from_origin) {
 129                 ret = -1;
 130                 goto end;
 131         }
 132
 133 add_value:
 134         *ns_from_origin += value_ns_signed;
 135
 136 end:
 137         return ret;
 138 }
 139
 140 static inline
 141 int bt_util_ns_from_origin_clock_class(const struct bt_clock_class *clock_class,
 142                 uint64_t value, int64_t *ns_from_origin)
 143 {
 144         int ret = 0;
 145
 146         if (clock_class->base_offset.overflows) {
 147                 ret = -1;
 148                 goto end;
 149         }
 150
 151         ret = bt_util_ns_from_origin_inline(clock_class->base_offset.value_ns,
 152                 clock_class->offset_seconds, clock_class->offset_cycles,
 153                 clock_class->frequency, value, ns_from_origin);
 154
 155 end:
 156         return ret;
 157 }
 158
 159 static inline
 160 bool bt_util_value_is_in_range_signed(uint64_t size, int64_t value)
 161 {
 162         int64_t min_value = UINT64_C(-1) << (size - 1);
 163         int64_t max_value = (UINT64_C(1) << (size - 1)) - 1;
 164         return value >= min_value && value <= max_value;
 165 }
 166
 167 static inline
 168 bool bt_util_value_is_in_range_unsigned(unsigned int size, uint64_t value)
 169 {
 170         uint64_t max_value = (size == 64) ? UINT64_MAX :
 171                 (UINT64_C(1) << size) - 1;
 172         return value <= max_value;
 173 }
 174
 175 #endif /* BABELTRACE_TRACE_IR_UTILS_INTERNAL_H */