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