Libwaku spike start (#510)

* libwaku init e2e

* basic cstring check

* wip

.gitignore

@@ -34,3 +34,5 @@ rln
 package-lock.json
 node_modules/
 /.update.timestamp
+
+libwaku

waku/v2/node/libwaku/README.md

@@ -0,0 +1,12 @@
+# libwaku
+
+Exposes a C API that can be used by other environments other than C.
+
+## Running
+
+Make sure you run `$PROJECTDIR/env.sh bash` first. Then:
+
+```
+./build.sh
+./libwaku
+```

waku/v2/node/libwaku/build.sh

@@ -0,0 +1,4 @@
+#!/usr/bin/env sh
+
+nim c --skipParentCfg libwaku.nim
+gcc libwaku.c ./libwaku.a -lm -g -o libwaku

waku/v2/node/libwaku/libwaku.c

@@ -0,0 +1,12 @@
+#include <stdio.h>
+#include <stddef.h>
+
+#include "libwaku.h"
+
+int main(int argc, char* argv[]) {
+  char* string;
+  NimMain();
+  //echo();
+  string = info("hello there");
+  printf("Info: %s", string);
+}

waku/v2/node/libwaku/libwaku.h

@@ -0,0 +1,9 @@
+#include <stdint.h>
+#include <stddef.h>
+
+// Initialize Nim
+void NimMain();
+
+char* info(const char* wakuNode);
+
+void echo();

waku/v2/node/libwaku/libwaku.nim

@@ -0,0 +1,36 @@
+# libwaku
+#
+# Exposes a C API that can be used by other environment than C.
+
+# TODO Start a node
+# TODO Mock info call
+# TODO Write header file
+# TODO Write example C code file
+# TODO Wrap info call
+# TODO Init a node
+
+# proc info*(node: WakuNode): WakuInfo =
+proc info(foo: cstring): cstring {.exportc.} =
+  echo "info about node"
+  echo foo
+  return foo
+
+proc echo() {.exportc.} =
+ echo "echo"
+
+# TODO Here at the moment, start the node
+# Then do info call
+# WIP
+#proc main() {.async.} =
+#  let
+#    rng = crypto.newRng()
+#    conf = WakuNodeConf.load()
+#    (extIp, extTcpPort, extUdpPort) = setupNat(conf.nat, clientId,
+#      Port(uint16(conf.tcpPort) + conf.portsShift),
+#      Port(uint16(conf.udpPort) + conf.portsShift))
+#    node = WakuNode.init(conf.nodeKey, conf.listenAddress,
+#      Port(uint16(conf.tcpPort) + conf.portsShift), extIp, extTcpPort)
+#
+#  await node.start()
+#
+#main()

waku/v2/node/libwaku/nim.cfg

@@ -0,0 +1,5 @@
+-app:staticlib
+o:"libwaku.a"
+noMain
+header
+-d:"chronicles_sinks=textlines"