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