From 37f6f96031eb61668061d105f5bed2b0ee547c94 Mon Sep 17 00:00:00 2001
From: Aleteoryx <alyx@aleteoryx.me>
Date: Mon, 2 Sep 2024 22:14:35 -0400
Subject: [PATCH] and that's a wrap, folks

---
 nex.nelua    | 18 +++++++++++++++---
 nps.nelua    | 37 +++++++++++++++++++++++++++++++++++++
 socket.nelua | 41 ++++++++++++++++++++++++++++++++++-------
 3 files changed, 86 insertions(+), 10 deletions(-)
 create mode 100644 nps.nelua

diff --git a/nex.nelua b/nex.nelua
index 9379752..397d02c 100644
--- a/nex.nelua
+++ b/nex.nelua
@@ -1,14 +1,26 @@
 local socket = require 'socket'
 
-socket.listen_tcp("127.0.0.1:1900", function()
+if #arg ~= 1 then
+  print("Usage: nex.nelua <ADDRESS>")
+  print("ADDRESS may be one of:")
+  print("  `<ipv4 addr>:<port>'")
+  print("  `{<ipv6 addr>}:<port>'")
+end
+
+socket.listen_tcp(arg[1], function()
   local line = socket.recv_line():gsub("\r", "")
 
   if line:subview(1, 1) == "/" then line = line:subview(2) end
 
   if line == "" then
-    socket.send_line("Hello!\nThis is the index page!\n\nThe protocol's originator:\n=> nex://nightfall.city")
+    socket.send_line([[Hello!
+
+This is the index page, edit nex.nelua to change it.
+
+For more info, go here:
+=> nex://nightfall.city/nex/info/specification.txt]])
   else
-    socket.send_line("Page not Found.")
+    socket.send_line("Page not Found. Try the root.")
   end
 
   socket.end_conn()
diff --git a/nps.nelua b/nps.nelua
new file mode 100644
index 0000000..114250c
--- /dev/null
+++ b/nps.nelua
@@ -0,0 +1,37 @@
+local socket = require 'socket'
+require 'vector'
+require 'io'
+require 'arg'
+
+if #arg ~= 1 then
+  print("Usage: nps.nelua <ADDRESS>")
+  print("ADDRESS may be one of:")
+  print("  `<ipv4 addr>:<port>'")
+  print("  `{<ipv6 addr>}:<port>'")
+end
+
+socket.listen_tcp(arg[1], function()
+  local target = socket.recv_line():gsub("\r", "")
+
+  local lines: vector(string)
+  local line = socket.recv_line()
+
+  while line:gsub("\r", "") ~= "." do
+    lines:push(line)
+    line = socket.recv_line()
+  end
+
+  local ok, matches
+  if (do ok, matches = target:match("^mail/(.+)$"); in ok end) then
+    io.writef("Mail for %s:\n", matches[1])
+    for i=0,<#lines do
+      print("Mail:", lines[i])
+    end
+  else
+    socket.send("Unknown target: ")
+    socket.send_line(target)
+    socket.send_line("If you're testing this out, try editing nps.nelua!")
+  end
+
+  socket.end_conn()
+end)
diff --git a/socket.nelua b/socket.nelua
index c53a74b..2459593 100644
--- a/socket.nelua
+++ b/socket.nelua
@@ -82,11 +82,6 @@ require 'allocators.default'
 
 local function fakeuse(...: varargs) end
 
--- 192.168.2.1:2000 -> 192.168.2.1,2000
-local inet_re = '^(%d?%d?%d%.%d?%d?%d%.%d?%d?%d%.%d?%d?%d):(%d?%d?%d?%d?%d)$'
--- {::1}:2000 -> ::1,2000
-local inet6_re = '^{([^}]+)}:(%d?%d?%d?%d?%d)$'
-
 local function die_errno(cond: boolean, msg: string): void
   if cond then
     C.perror(nilptr)
@@ -255,9 +250,13 @@ function export.listen_sock(sock: cint, handler: function(): void): void
   end
 end
 
+-- 192.168.2.1:2000 -> 192.168.2.1,2000
+local inet_re = '^(%d?%d?%d%.%d?%d?%d%.%d?%d?%d%.%d?%d?%d):(%d?%d?%d?%d?%d)$'
+-- {::1}:2000 -> ::1,2000
+local inet6_re = '^{([^}]+)}:(%d?%d?%d?%d?%d)$'
 function export.listen_tcp(address: string, handler: function(): void): void
-  local matched, matches = string.match(address, inet_re)
-  if matched then
+  local matched, matches
+  if (do matched, matches = address:match(inet_re); in matched end) then
     local c_err: cint = 0
 
     local s_addr, s_port = matches:unpack(1, 2)
@@ -284,6 +283,34 @@ function export.listen_tcp(address: string, handler: function(): void): void
 
     defer c_close(fd) end
 
+    export.listen_sock(fd, handler)
+  elseif (do matched, matches = address:match(inet6_re); in matched end) then
+    local c_err: cint = 0
+
+    local s_addr, s_port = matches:unpack(1, 2)
+    local addr: [16]byte
+    die_errno(c_inet_pton(AF_INET6, (@cstring)(s_addr), &addr) <= 0,
+              "bad IPv6 address")
+    local i_port = tointeger(s_port)
+    assert((i_port >= 0) and (i_port < 65535), "port not within range [0,65536)")
+    local port: uint16 = c_htons(i_port)
+
+    local fd = c_socket(AF_INET6, SOCK_STREAM, 0)
+    die_errno(fd == -1, "couldn't open TCP socket")
+
+    fakeuse(port)
+    ##[==[ cemit [[
+      struct sockaddr_in6 sa;
+      memset(&sa, 0, sizeof(sa));
+      sa.sin6_family = AF_INET6;
+      sa.sin6_port = port;
+      memcpy(&sa.sin6_addr.s6_addr, &addr, sizeof(addr));
+      c_err = bind(fd, &sa, sizeof(sa));
+    ]] ]==]
+    die_errno(c_err == -1, "couldn't bind TCP socket")
+
+    defer c_close(fd) end
+
     export.listen_sock(fd, handler)
   end
 end
-- 
2.43.4