Various std net improvements (#19132)

* Variant of  that works with raw IpAddresses.

- Add doc tests for new net proc's.
- Aadd recvFrom impl
- Add recvFrom impl -- tweak handling data var

- Update lib/pure/net.nim
	Co-authored-by: Dominik Picheta <dominikpicheta@googlemail.com>

- cleaning up sendTo args
- remove extra connect test
- cleaning up sendTo args
- fix inet_ntop test
- fix test failing - byte len

* fix test failing - byte len

* debugging odd windows build failure

* debugging odd windows build failure

* more experiments to figure out the windows failure

* try manual assigment on InAddr

Co-authored-by: Jaremy Creechley <jaremy.creechley@panthalassa.com>

lib/posix/posix.nim

@@ -155,9 +155,9 @@ when not defined(zephyr):
   proc inet_addr*(a1: cstring): InAddrT {.importc, header: "<arpa/inet.h>".}
   proc inet_ntoa*(a1: InAddr): cstring {.importc, header: "<arpa/inet.h>".}
 
-proc inet_ntop*(a1: cint, a2: pointer, a3: cstring, a4: int32): cstring {.
+proc inet_ntop*(a1: cint, a2: pointer | ptr InAddr | ptr In6Addr, a3: cstring, a4: int32): cstring {.
   importc:"(char *)$1", header: "<arpa/inet.h>".}
-proc inet_pton*(a1: cint, a2: cstring, a3: pointer): cint {.
+proc inet_pton*(a1: cint, a2: cstring, a3: pointer | ptr InAddr | ptr In6Addr): cint {.
   importc, header: "<arpa/inet.h>".}
 
 var

lib/pure/net.nim

@@ -65,6 +65,11 @@ runnableExamples("-r:off"):
   let socket = newSocket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)
   socket.sendTo("192.168.0.1", Port(27960), "status\n")
 
+runnableExamples("-r:off"):
+  let socket = newSocket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)
+  let ip = parseIpAddress("192.168.0.1")
+  doAssert socket.sendTo(ip, Port(27960), "status\c\l") == 8
+
 ## Creating a server
 ## -----------------
 ##
@@ -1607,11 +1612,12 @@ proc recvLine*(socket: Socket, timeout = -1,
   result = ""
   readLine(socket, result, timeout, flags, maxLength)
 
-proc recvFrom*(socket: Socket, data: var string, length: int,
+proc recvFrom*[T: string | IpAddress](socket: Socket, data: var string, length: int,
-               address: var string, port: var Port, flags = 0'i32): int {.
+               address: var T, port: var Port, flags = 0'i32): int {.
                tags: [ReadIOEffect].} =
   ## Receives data from `socket`. This function should normally be used with
-  ## connection-less sockets (UDP sockets).
+  ## connection-less sockets (UDP sockets). The source address of the data
+  ## packet is stored in the `address` argument as either a string or an IpAddress.
   ##
   ## If an error occurs an OSError exception will be raised. Otherwise the return
   ## value will be the length of data received.
@@ -1620,31 +1626,37 @@ proc recvFrom*(socket: Socket, data: var string, length: int,
   ##   so when `socket` is buffered the non-buffered implementation will be
   ##   used. Therefore if `socket` contains something in its buffer this
   ##   function will make no effort to return it.
-  template adaptRecvFromToDomain(domain: Domain) =
+  template adaptRecvFromToDomain(sockAddress: untyped, domain: Domain) =
     var addrLen = sizeof(sockAddress).SockLen
     result = recvfrom(socket.fd, cstring(data), length.cint, flags.cint,
                       cast[ptr SockAddr](addr(sockAddress)), addr(addrLen))
 
     if result != -1:
       data.setLen(result)
+
+      when typeof(address) is string:
         address = getAddrString(cast[ptr SockAddr](addr(sockAddress)))
         when domain == AF_INET6:
           port = ntohs(sockAddress.sin6_port).Port
         else:
           port = ntohs(sockAddress.sin_port).Port
+      else:
+        data.setLen(result)
+        sockAddress.fromSockAddr(addrLen, address, port)
     else:
       raiseOSError(osLastError())
 
   assert(socket.protocol != IPPROTO_TCP, "Cannot `recvFrom` on a TCP socket")
   # TODO: Buffered sockets
   data.setLen(length)
+
   case socket.domain
   of AF_INET6:
     var sockAddress: Sockaddr_in6
-    adaptRecvFromToDomain(AF_INET6)
+    adaptRecvFromToDomain(sockAddress, AF_INET6)
   of AF_INET:
     var sockAddress: Sockaddr_in
-    adaptRecvFromToDomain(AF_INET)
+    adaptRecvFromToDomain(sockAddress, AF_INET)
   else:
     raise newException(ValueError, "Unknown socket address family")
 
@@ -1707,7 +1719,8 @@ proc sendTo*(socket: Socket, address: string, port: Port, data: pointer,
              tags: [WriteIOEffect].} =
   ## This proc sends `data` to the specified `address`,
   ## which may be an IP address or a hostname, if a hostname is specified
-  ## this function will try each IP of that hostname.
+  ## this function will try each IP of that hostname. This function
+  ## should normally be used with connection-less sockets (UDP sockets).
   ##
   ## If an error occurs an OSError exception will be raised.
   ##
@@ -1742,11 +1755,37 @@ proc sendTo*(socket: Socket, address: string, port: Port,
   ## which may be an IP address or a hostname, if a hostname is specified
   ## this function will try each IP of that hostname.
   ## 
+  ## Generally for use with connection-less (UDP) sockets.
+  ##
   ## If an error occurs an OSError exception will be raised.
   ##
   ## This is the high-level version of the above `sendTo` function.
   socket.sendTo(address, port, cstring(data), data.len, socket.domain)
 
+proc sendTo*(socket: Socket, address: IpAddress, port: Port,
+             data: string, flags = 0'i32): int {.
+              discardable, tags: [WriteIOEffect].} =
+  ## This proc sends `data` to the specified `IpAddress` and returns
+  ## the number of bytes written. 
+  ##
+  ## Generally for use with connection-less (UDP) sockets. 
+  ##
+  ## If an error occurs an OSError exception will be raised.
+  ##
+  ## This is the high-level version of the above `sendTo` function.
+  assert(socket.protocol != IPPROTO_TCP, "Cannot `sendTo` on a TCP socket")
+  assert(not socket.isClosed, "Cannot `sendTo` on a closed socket")
+
+  var sa: Sockaddr_storage
+  var sl: Socklen
+  toSockAddr(address, port, sa, sl)
+  result = sendto(socket.fd, cstring(data), data.len().cint, flags.cint,
+                  cast[ptr SockAddr](addr sa), sl)
+
+  if result == -1'i32:
+    let osError = osLastError()
+    raiseOSError(osError)
+
 
 proc isSsl*(socket: Socket): bool =
   ## Determines whether `socket` is a SSL socket.

tests/stdlib/tnet_ll.nim

@@ -23,13 +23,15 @@ suite "inet_ntop tests":
       discard wsaStartup(0x101'i16, wsa.addr)
   
   test "IP V4":
-    var ip4 = 0x10111213
+    # regular
+    var ip4 = InAddr()
+    ip4.s_addr = 0x10111213'u32
+
     var buff: array[0..255, char]
-    let r = inet_ntop(AF_INET, ip4.addr, buff[0].addr, buff.sizeof.int32)
+    let r = inet_ntop(AF_INET, cast[pointer](ip4.s_addr.addr), buff[0].addr, buff.len.int32)
     let res = if r == nil: "" else: $r
     check: res == "19.18.17.16"
       
-
   test "IP V6":
     when defined(windows):
       let ipv6Support = (getVersion() and 0xff) > 0x5
@@ -38,6 +40,6 @@ suite "inet_ntop tests":
           
     var ip6 = [0x1000'u16, 0x1001, 0x2000, 0x2001, 0x3000, 0x3001, 0x4000, 0x4001]
     var buff: array[0..255, char]
-    let r = inet_ntop(AF_INET6, ip6[0].addr, buff[0].addr, buff.sizeof.int32)
+    let r = inet_ntop(AF_INET6, cast[pointer](ip6[0].addr), buff[0].addr, buff.len.int32)
     let res = if r == nil: "" else: $r
     check: not ipv6Support or res == "10:110:20:120:30:130:40:140"