`flare.dns.resolver`

DNS hostname resolution via libc getaddrinfo(3).

References: - https://man7.org/linux/man-pages/man3/getaddrinfo.3.html - flare/net/_libc.mojo for low-level FFI wrappers

Memory safety contract: _freeaddrinfo MUST be called on the linked-list head in ALL code paths — including every error path that follows a successful _getaddrinfo call. This invariant is maintained by calling _freeaddrinfo(head) before every raise and at the successful return path.

Functions

`resolve`

def resolve(host: String) -> List[IpAddr]

Resolve a hostname to a list of IP addresses.

Calls getaddrinfo(3) which respects /etc/hosts, /etc/resolv.conf, and nsswitch.conf. Returns both IPv4 and IPv6 results in OS-preference order.

Example:

var addrs = resolve("localhost")
for a in addrs:
    print(a[])

Args: host: Hostname or numeric IP string to resolve (e.g. "example.com", "localhost", "127.0.0.1").

Raises AddressParseError: If host is empty, longer than 253 bytes (one trailing root dot, as in "example.com.", is not counted), has a label over 63 bytes, or contains a NUL, CR, LF or @. The too-long message quotes the first 20 bytes of the host, cut at a character boundary so the text stays valid UTF-8. DnsError: On NXDOMAIN, timeout, or system resolver failure.

`resolve_v4`

def resolve_v4(host: String) -> List[IpAddr]

Resolve a hostname, returning only IPv4 results.

Example:

var addrs = resolve_v4("localhost")
print(addrs[0]) # 127.0.0.1

Args: host: Hostname to resolve.

Raises AddressParseError: If host is empty. DnsError: If no IPv4 address is found, or resolution fails.

`resolve_v6`

def resolve_v6(host: String) -> List[IpAddr]

Resolve a hostname, returning only IPv6 results.

Args: host: Hostname to resolve.

Raises AddressParseError: If host is empty. DnsError: If no IPv6 address is found, or resolution fails.