src/cpp-common/uuid-view.hpp

   1 /*
   2  * SPDX-FileCopyrightText: 2020 Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * SPDX-License-Identifier: MIT
   5  */
   6
   7 #ifndef BABELTRACE_CPP_COMMON_UUID_VIEW_HPP
   8 #define BABELTRACE_CPP_COMMON_UUID_VIEW_HPP
   9
  10 #include <algorithm>
  11 #include <cstdint>
  12 #include <string>
  13
  14 #include "common/assert.h"
  15 #include "common/uuid.h"
  16
  17 namespace bt2_common {
  18
  19 class Uuid;
  20
  21 /*
  22  * A view on existing UUID data.
  23  *
  24  * A `UuidView` object doesn't contain its UUID data: see `Uuid` for a
  25  * UUID data container.
  26  */
  27 class UuidView final
  28 {
  29 public:
  30     using Val = std::uint8_t;
  31     using ConstIter = const Val *;
  32
  33 public:
  34     explicit UuidView(const Val * const uuid) noexcept : _mUuid {uuid}
  35     {
  36         BT_ASSERT_DBG(uuid);
  37     }
  38
  39     explicit UuidView(const Uuid& uuid) noexcept;
  40     UuidView(const UuidView&) noexcept = default;
  41     UuidView& operator=(const UuidView&) noexcept = default;
  42
  43     UuidView& operator=(const Val * const uuid) noexcept
  44     {
  45         _mUuid = uuid;
  46         return *this;
  47     }
  48
  49     operator Uuid() const noexcept;
  50
  51     std::string str() const
  52     {
  53         std::string s;
  54
  55         s.resize(BT_UUID_STR_LEN);
  56         bt_uuid_to_str(_mUuid, &s[0]);
  57
  58         return s;
  59     }
  60
  61     bool operator==(const UuidView& other) const noexcept
  62     {
  63         return bt_uuid_compare(_mUuid, other._mUuid) == 0;
  64     }
  65
  66     bool operator!=(const UuidView& other) const noexcept
  67     {
  68         return !(*this == other);
  69     }
  70
  71     bool operator<(const UuidView& other) const noexcept
  72     {
  73         return bt_uuid_compare(_mUuid, other._mUuid) < 0;
  74     }
  75
  76     static constexpr std::size_t size() noexcept
  77     {
  78         return BT_UUID_LEN;
  79     }
  80
  81     const Val *data() const noexcept
  82     {
  83         return _mUuid;
  84     }
  85
  86     Val operator[](const std::size_t index) const noexcept
  87     {
  88         return _mUuid[index];
  89     }
  90
  91     ConstIter begin() const noexcept
  92     {
  93         return _mUuid;
  94     }
  95
  96     ConstIter end() const noexcept
  97     {
  98         return _mUuid + this->size();
  99     }
 100
 101     bool isNil() const noexcept
 102     {
 103         return std::all_of(this->begin(), this->end(), [](const std::uint8_t byte) {
 104             return byte == 0;
 105         });
 106     }
 107
 108 private:
 109     const Val *_mUuid;
 110 };
 111
 112 } /* namespace bt2_common */
 113
 114 #endif /* BABELTRACE_CPP_COMMON_UUID_VIEW_HPP */