mpd/src/net/StaticSocketAddress.hxx
2024-05-06 12:50:24 +02:00

147 lines
3.1 KiB
C++

// SPDX-License-Identifier: BSD-2-Clause
// author: Max Kellermann <max.kellermann@gmail.com>
#pragma once
#include "SocketAddress.hxx" // IWYU pragma: export
#include "Features.hxx"
#include <cassert>
#ifdef HAVE_UN
#include <string_view>
#endif
/**
* An OO wrapper for struct sockaddr_storage.
*/
class StaticSocketAddress {
friend class SocketDescriptor;
public:
typedef SocketAddress::size_type size_type;
private:
size_type size;
struct sockaddr_storage address;
public:
constexpr StaticSocketAddress() noexcept = default;
explicit StaticSocketAddress(SocketAddress src) noexcept {
*this = src;
}
StaticSocketAddress &operator=(SocketAddress other) noexcept;
constexpr operator SocketAddress() const noexcept {
return SocketAddress(*this, size);
}
constexpr operator struct sockaddr *() noexcept {
return (struct sockaddr *)(void *)&address;
}
constexpr operator const struct sockaddr *() const noexcept {
return (const struct sockaddr *)(const void *)&address;
}
/**
* Cast the "sockaddr" pointer to a different address type,
* e.g. "sockaddr_in". This is only legal after checking
* GetFamily().
*/
template<typename T>
constexpr const T &CastTo() const noexcept {
/* cast through void to work around the bogus
alignment warning */
const void *q = reinterpret_cast<const void *>(&address);
return *reinterpret_cast<const T *>(q);
}
constexpr size_type GetCapacity() const noexcept {
return sizeof(address);
}
constexpr size_type GetSize() const noexcept {
return size;
}
constexpr void SetSize(size_type _size) noexcept {
assert(_size > 0);
assert(size_t(_size) <= sizeof(address));
size = _size;
}
/**
* Set the size to the maximum value for this class.
*/
constexpr void SetMaxSize() {
SetSize(GetCapacity());
}
constexpr int GetFamily() const noexcept {
return address.ss_family;
}
constexpr bool IsDefined() const noexcept {
return GetFamily() != AF_UNSPEC;
}
constexpr void Clear() noexcept {
size = sizeof(address.ss_family);
address.ss_family = AF_UNSPEC;
}
constexpr bool IsInet() const noexcept {
return GetFamily() == AF_INET || GetFamily() == AF_INET6;
}
#ifdef HAVE_UN
/**
* @see SocketAddress::GetLocalRaw()
*/
[[gnu::pure]]
std::string_view GetLocalRaw() const noexcept;
/**
* @see SocketAddress::GetLocalPath()
*/
[[nodiscard]] [[gnu::pure]]
const char *GetLocalPath() const noexcept {
return static_cast<const SocketAddress>(*this).GetLocalPath();
}
#endif
#ifdef HAVE_TCP
/**
* Extract the port number. Returns 0 if not applicable.
*/
[[gnu::pure]]
unsigned GetPort() const noexcept {
return ((SocketAddress)*this).GetPort();
}
/**
* @return true on success, false if this address cannot have
* a port number
*/
bool SetPort(unsigned port) noexcept;
#endif
[[gnu::pure]]
std::span<const std::byte> GetSteadyPart() const noexcept {
return SocketAddress{*this}.GetSteadyPart();
}
[[gnu::pure]]
bool operator==(SocketAddress other) const noexcept {
return (SocketAddress)*this == other;
}
bool operator!=(SocketAddress other) const noexcept {
return !(*this == other);
}
};