upd5

addr_and_name_info.c.v

@@ -0,0 +1,120 @@
+module netio
+
+import os
+
+#include <netdb.h>
+
+fn C.getaddrinfo(&char, &char, &C.addrinfo, &&C.addrinfo) i32
+fn C.freeaddrinfo(&C.addrinfo)
+fn C.getnameinfo(voidptr, i32, &char, i32, &char, i32, i32) i32
+fn C.gai_strerror(i32) &char
+
+struct C.addrinfo {
+mut:
+	ai_flags     i32
+	ai_family    i32
+	ai_socktype  i32
+	ai_protocol  i32
+	ai_addrlen   i32
+	ai_addr      voidptr
+	ai_canonname voidptr
+	ai_next      voidptr
+}
+
+// AddrInfo represents the [addrinfo](https://man7.org/linux/man-pages/man3/getaddrinfo.3.html) struct.
+pub struct AddrInfo {
+pub:
+	flags     AddrInfoFlag
+	family    AddrFamily
+	socktype SocketType
+	protocol  Protocol
+	addr      SocketAddr
+	canonical string
+}
+
+@[params]
+pub struct AddrInfoParams {
+pub:
+	node      ?string
+	service   ?string
+	family    AddrFamily = af_unspec
+	socktype SocketType
+	protocol  Protocol
+	flags     AddrInfoFlag
+}
+
+// addr_info translates the network addresses and services. This is a low-level wrapper around
+// the [getaddrinfo(3)](https://man7.org/linux/man-pages/man3/getaddrinfo.3.html) C API.
+pub fn addr_info(hints AddrInfoParams) ![]AddrInfo {
+	mut hints_ := C.addrinfo{}
+	unsafe { vmemset(&hints_, 0, int(sizeof(hints_))) }
+	hints_.ai_family = i32(hints.family)
+	hints_.ai_socktype = i32(hints.socktype)
+	hints_.ai_protocol = i32(hints.protocol)
+	hints_.ai_flags = i32(hints.flags)
+	mut node := unsafe { nil }
+	if hints.node != none {
+		node = &char(hints.node.str)
+	}
+	mut service := unsafe { nil }
+	if hints.service != none {
+		service = &char(hints.service.str)
+	}
+	mut results := &C.addrinfo(unsafe { nil })
+	code := C.getaddrinfo(node, service, &hints_, &results)
+	if code != 0 {
+		if code == C.EAI_SYSTEM {
+			return os.last_error()
+		}
+		msg := C.gai_strerror(code)
+		return error_with_code(unsafe { cstring_to_vstring(msg) }, code)
+	}
+	defer {
+		C.freeaddrinfo(results)
+	}
+	mut addrs := []AddrInfo{}
+	for result := unsafe { results }; !isnil(result); result = result.ai_next {
+		addrs << AddrInfo{
+			flags:     int(result.ai_flags)
+			family:    int(result.ai_family)
+			socktype: int(result.ai_socktype)
+			protocol:  int(result.ai_protocol)
+			addr:      unsafe { SocketAddr.from_ptr(result.ai_addr, result.ai_addrlen)! }
+			canonical: if isnil(result.ai_canonname) {
+				''
+			} else {
+				unsafe {
+					cstring_to_vstring(result.ai_canonname)
+				}
+			}
+		}
+	}
+	return addrs
+}
+
+@[params]
+pub struct NameInfoParams {
+pub:
+	flags NameInfoFlag
+}
+
+// name_info does address-to-name translation and returns the host and service names.
+// See [getnameinfo(3)](https://man7.org/linux/man-pages/man3/getnameinfo.3.html) for details.
+pub fn name_info(sa SocketAddr, params NameInfoParams) !(string, string) {
+	mut addr := []u8{len: C.NI_MAXHOST}
+	mut serv := []u8{len: C.NI_MAXSERV}
+	code := C.getnameinfo(sa.ptr(), sa.size(), addr.data, addr.len, serv.data, serv.len,
+		params.flags)
+	if code != 0 {
+		if code == C.EAI_SYSTEM {
+			return os.last_error()
+		}
+		msg := C.gai_strerror(code)
+		return error_with_code(unsafe { cstring_to_vstring(msg) }, code)
+	}
+	return unsafe {
+		tos_clone(&u8(addr.data))
+	}, unsafe {
+		tos_clone(&u8(serv.data))
+	}
+}