Fixing issue #15302 -- lwip doesn't support signals (#15303)

* Fixing issue #15302 -- lwip doesn't support signals

* Adding test to catch issue #15302 -- lwip/freertos net library
don't try to build / run on windows, it'll compile only but not run

Fixing issue #15302 -- reworking test to compile on other platforms

compiler/platform.nim

@@ -179,7 +179,7 @@ const
       props: {ospNeedsPIC, ospPosix}),
      (name: "FreeRTOS", parDir: "..", dllFrmt: "lib$1.so", altDirSep: "/",
       objExt: ".o", newLine: "\x0A", pathSep: ":", dirSep: "/",
-      scriptExt: ".sh", curDir: ".", exeExt: ".elf", extSep: ".",
+      scriptExt: ".sh", curDir: ".", exeExt: "", extSep: ".",
       props: {ospPosix}),
      (name: "Any", parDir: "..", dllFrmt: "lib$1.so", altDirSep: "/",
       objExt: ".o", newLine: "\x0A", pathSep: ":", dirSep: "/",

lib/posix/posix_freertos_consts.nim

@@ -220,11 +220,11 @@ var IPV6_UNICAST_HOPS* {.importc: "IPV6_UNICAST_HOPS", header: "<sys/socket.h>".
 var IPV6_V6ONLY* {.importc: "IPV6_V6ONLY", header: "<sys/socket.h>".}: cint
 
 # <netinet/tcp.h>
-var TCP_NODELAY* {.importc: "TCP_NODELAY", header: "<sys/socket.h>".}: cint
+const TCP_NODELAY*    = 0x01    # don't delay send to coalesce packets
-var TCP_KEEPALIVE* {.importc: "TCP_KEEPALIVE", header: "<sys/socket.h>".}: cint
+const TCP_KEEPALIVE*  = 0x02    # send KEEPALIVE probes when idle for pcb->keep_idle milliseconds
-var TCP_KEEPIDLE* {.importc: "TCP_KEEPIDLE", header: "<sys/socket.h>".}: cint
+const TCP_KEEPIDLE*   = 0x03    # set pcb->keep_idle  - Same as TCP_KEEPALIVE, but use seconds for get/setsockopt
-var TCP_KEEPINTVL* {.importc: "TCP_KEEPINTVL", header: "<sys/socket.h>".}: cint
+const TCP_KEEPINTVL*  = 0x04    # set pcb->keep_intvl - Use seconds for get/setsockopt
-var TCP_KEEPCNT* {.importc: "TCP_KEEPCNT", header: "<sys/socket.h>".}: cint
+const TCP_KEEPCNT*    = 0x05    # set pcb->keep_cnt   - Use number of probes sent for get/setsockopt
 
 # <nl_types.h>
 # var NL_SETD* {.importc: "NL_SETD", header: "<nl_types.h>".}: cint
@@ -367,10 +367,25 @@ var SEM_FAILED* {.importc: "SEM_FAILED", header: "<semaphore.h>".}: pointer
 var FD_SETSIZE* {.importc: "FD_SETSIZE", header: "<sys/select.h>".}: cint
 
 # <sys/socket.h>
-var MSG_CTRUNC* {.importc: "MSG_CTRUNC", header: "<sys/socket.h>".}: cint
+# struct msghdr->msg_flags bit field values 
-var MSG_DONTROUTE* {.importc: "MSG_DONTROUTE", header: "<sys/socket.h>".}: cint
+const MSG_TRUNC*   = 0x04
-var MSG_EOR* {.importc: "MSG_EOR", header: "<sys/socket.h>".}: cint
+const MSG_CTRUNC*  = 0x08
-var MSG_OOB* {.importc: "MSG_OOB", header: "<sys/socket.h>".}: cint
+
+# Flags we can use with send and recv.
+const MSG_PEEK*       = 0x01    # Peeks at an incoming message
+const MSG_WAITALL*    = 0x02    # Unimplemented: Requests that the function block until the full amount of data requested can be returned
+const MSG_OOB*        = 0x04    # Unimplemented: Requests out-of-band data. The significance and semantics of out-of-band data are protocol-specific
+const MSG_DONTWAIT*   = 0x08    # Nonblocking i/o for this operation only
+const MSG_MORE*       = 0x10    # Sender will send more
+# const MSG_NOSIGNAL*   = 0x20    # Uninmplemented: Requests not to send the SIGPIPE signal if an attempt to send is made on a stream-oriented socket that is no longer connected.
+
+# Alternately, they can defined like this, but the above seems better when they're known/stable values:
+# var MSG_TRUNC* {.importc: "MSG_TRUNC", header: "<sys/socket.h>".}: cint
+# var MSG_CTRUNC* {.importc: "MSG_CTRUNC", header: "<sys/socket.h>".}: cint
+# var MSG_DONTROUTE* {.importc: "MSG_DONTROUTE", header: "<sys/socket.h>".}: cint # not defined in lwip
+# var MSG_EOR* {.importc: "MSG_EOR", header: "<sys/socket.h>".}: cint # not defined in lwip
+# var MSG_OOB* {.importc: "MSG_OOB", header: "<sys/socket.h>".}: cint
+
 
 # var SCM_RIGHTS* {.importc: "SCM_RIGHTS", header: "<sys/socket.h>".}: cint
 var SO_ACCEPTCONN* {.importc: "SO_ACCEPTCONN", header: "<sys/socket.h>".}: cint
@@ -401,9 +416,6 @@ var SOL_SOCKET* {.importc: "SOL_SOCKET", header: "<sys/socket.h>".}: cint
 const SocketMaxConnections {.intdefine.}: int = 32
 var SOMAXCONN*: cint = SocketMaxConnections.cint
 
-var MSG_PEEK* {.importc: "MSG_PEEK", header: "<sys/socket.h>".}: cint
-var MSG_TRUNC* {.importc: "MSG_TRUNC", header: "<sys/socket.h>".}: cint
-var MSG_WAITALL* {.importc: "MSG_WAITALL", header: "<sys/socket.h>".}: cint
 var AF_INET* {.importc: "AF_INET", header: "<sys/socket.h>".}: cint
 var AF_INET6* {.importc: "AF_INET6", header: "<sys/socket.h>".}: cint
 # var AF_UNIX* {.importc: "AF_UNIX", header: "<sys/socket.h>".}: cint

lib/posix/posix_other.nim

@@ -625,6 +625,10 @@ elif defined(solaris):
   # Solaris doesn't have MSG_NOSIGNAL
   const
     MSG_NOSIGNAL* = 0'i32
+elif defined(freertos) or defined(lwip):
+  # LwIP/FreeRTOS doesn't have MSG_NOSIGNAL
+  const
+    MSG_NOSIGNAL* = 0x20'i32
 else:
   var
     MSG_NOSIGNAL* {.importc, header: "<sys/socket.h>".}: cint

lib/pure/net.nim

@@ -1061,7 +1061,7 @@ proc accept*(server: Socket, client: var owned(Socket),
   var addrDummy = ""
   acceptAddr(server, client, addrDummy, flags)
 
-when defined(posix):
+when defined(posix) and not defined(lwip):
   from posix import Sigset, sigwait, sigismember, sigemptyset, sigaddset,
     sigprocmask, pthread_sigmask, SIGPIPE, SIG_BLOCK, SIG_UNBLOCK
 
@@ -1079,7 +1079,7 @@ template blockSigpipe(body: untyped): untyped =
   ##
   ## For convenience, this template is also available for non-POSIX system,
   ## where `body` will be executed as-is.
-  when not defined(posix):
+  when not defined(posix) or defined(lwip):
     body
   else:
     template sigmask(how: cint, set, oset: var Sigset): untyped {.gensym.} =

tests/stdlib/tlwip.nim

@@ -0,0 +1,30 @@
+discard """
+  targets: "c"
+  cmd: "nim $target --os:freertos --gc:arc $options $file"
+  disabled: "bsd"
+  disabled: "windows"
+  action: compile
+"""
+
+# Note:
+#   This file tests FreeRTOS/LwIP cross-compilation on UNIX platforms
+#   Windows should run when compiled with esp-idf, however I'm not
+#   sure how to test for only compilation on Windows without running 
+#   a test exe
+# 
+# Note:
+#   disabling *BSDs since they're not playing well with `gcc`
+
+import net
+import asynchttpserver, asyncdispatch
+
+proc cb*(req: Request) {.async.} =
+  await req.respond(Http200, "Hello World")
+
+proc run_http_server*() {.exportc.} =
+  echo "starting http server"
+  var server = newAsyncHttpServer()
+
+  waitFor server.serve(Port(8181), cb)
+
+echo("ok")