loader: add gopher support

works
author: bptato <nincsnevem662@gmail.com> 2023-09-20 01:12:46 +0200
committer: bptato <nincsnevem662@gmail.com> 2023-09-20 01:14:15 +0200
commit: ecfdd90f7947b65db1046cb2eeeaa8f1953b119f (patch)
tree: be0cc64cc1a3138c8d83205e1284309406ce96aa /src/loader
parent: a0f3631cc7373b513fa1ae2e9523b1db9dfc6eee (diff)
download: chawan-ecfdd90f7947b65db1046cb2eeeaa8f1953b119f.tar.gz
3 files changed, 269 insertions, 0 deletions
diff --git a/src/loader/gopher.nim b/src/loader/gopher.nim
new file mode 100644
index 00000000..3ccfc72a
--- /dev/null
+++ b/src/loader/gopher.nim
@@ -0,0 +1,254 @@
+import options
+import strutils
+
+import bindings/curl
+import loader/connecterror
+import loader/curlhandle
+import loader/curlwrap
+import loader/headers
+import loader/loaderhandle
+import loader/request
+import types/opt
+import types/url
+import utils/twtstr
+
+type GopherType = enum
+  UNKNOWN = "unsupported"
+  TEXT_FILE = "text file"
+  ERROR = "error"
+  DIRECTORY = "directory"
+  DOS_BINARY = "DOS binary"
+  SEARCH = "search"
+  MESSAGE = "message"
+  SOUND = "sound"
+  GIF = "gif"
+  HTML = "HTML"
+  INFO = ""
+  IMAGE = "image"
+  BINARY = "binary"
+  PNG = "png"
+
+type GopherHandle = ref object of CurlHandle
+  t: GopherType
+  buffer: string
+  ispre: bool
+  surl: string
+
+func gopherType(c: char): GopherType =
+  return case c
+  of '0': TEXT_FILE
+  of '1': DIRECTORY
+  of '3': ERROR
+  of '5': DOS_BINARY
+  of '7': SEARCH
+  of 'm': MESSAGE
+  of 's': SOUND
+  of 'g': GIF
+  of 'h': HTML
+  of 'i': INFO
+  of 'I': IMAGE
+  of '9': BINARY
+  of 'p': PNG
+  else: UNKNOWN
+
+func newGopherHandle(curl: CURL, request: Request, handle: LoaderHandle,
+    t: GopherType): GopherHandle =
+  return GopherHandle(
+    curl: curl,
+    handle: handle,
+    request: request,
+    t: t
+  )
+
+proc onStatusLine(op: GopherHandle): bool =
+  if not op.handle.sendResult(int(CURLE_OK)):
+    return false
+  var status: clong
+  op.curl.getinfo(CURLINFO_RESPONSE_CODE, addr status)
+  if not op.handle.sendStatus(cast[int](status)):
+    return false
+  let headers = case op.t
+  of DIRECTORY, SEARCH, HTML:
+    newHeaders({"Content-Type": "text/html"})
+  of GIF:
+    newHeaders({"Content-Type": "image/gif"})
+  of PNG:
+    newHeaders({"Content-Type": "image/png"})
+  of TEXT_FILE, ERROR:
+    newHeaders({"Content-Type": "text/plain"})
+  else:
+    newHeaders()
+  if not op.handle.sendHeaders(headers):
+    return false
+  if op.t in {DIRECTORY, SEARCH}:
+    var heads = """
+<!DOCTYPE HTML>
+<HTML>
+<HEAD>
+<BASE HREF="""" & $op.request.url & """">
+</HEAD>
+<BODY>
+  """
+    if op.t == DIRECTORY:
+      heads &= "<H1>Index of " & htmlEscape(op.surl) & "</H1>"
+    else: # search
+      heads &= "<H1>Search " & htmlEscape(op.surl) & "</H1>"
+    if not op.handle.sendData(heads):
+      return false
+  return true
+
+proc loadSearch(op: GopherHandle) =
+  discard op.handle.sendResult(int(CURLE_OK))
+  discard op.handle.sendStatus(200) # ok
+  discard op.handle.sendHeaders(newHeaders({"Content-Type": "text/html"}))
+  var heads = """
+<!DOCTYPE HTML>
+<HTML>
+<HEAD>
+<BASE HREF="""" & $op.request.url & """">
+</HEAD>
+<BODY>
+<H1>Search """ & htmlEscape(op.surl) & """</H1>
+<FORM>
+<INPUT TYPE=SEARCH NAME="NAME">
+</FORM>
+</BODY>
+</HTML>
+"""
+  discard op.handle.sendData(heads)
+
+proc flushLine(op: GopherHandle, s: string, fromi, toi: int): bool =
+  if toi == fromi + 1 and s[fromi] == '.':
+    return true #TODO this is the file end. maybe return false?
+  if s.len == 0:
+    return true # invalid
+  var i = fromi
+  let tc = s[i]
+  let t = gopherType(tc)
+  inc i
+  let ni = i
+  while i < toi and s[i] != '\t': inc i
+  let name = s.substr(ni, i - 1)
+  inc i
+  let fi = i
+  while i < toi and s[i] != '\t': inc i
+  let file = s.substr(fi, i - 1)
+  inc i
+  let hi = i
+  while i < toi and s[i] != '\t': inc i
+  let host = s.substr(hi, i - 1)
+  inc i
+  let pi = i
+  while i < toi and s[i] notin {'\t', '\r', '\n'}: inc i
+  let port = s.substr(pi, i - 1)
+  var line: string
+  if t == INFO:
+    if not op.ispre:
+      op.ispre = true
+      line = "<PRE>"
+    line &= htmlEscape(name) & "\n"
+  else:
+    if op.ispre:
+      line = "</PRE>"
+      op.ispre = false
+    let ts = $t
+    var names = ""
+    if ts != "":
+      names &= '[' & ts & ']'
+    names &= htmlEscape(name)
+    var ourls: string
+    if not file.startsWith("URL:"):
+      let file = if file.len > 0 and file[0] == '/':
+        file
+      else:
+        '/' & file
+      let pefile = percentEncode(file, PathPercentEncodeSet)
+      let iurls = "gopher://" & host & ":" & port & "/" & tc & pefile
+      let url = newURL(iurls)
+      ourls = if url.isSome: $url.get else: ""
+    else:
+      ourls = file.substr("URL:".len)
+    line &= "<A HREF=\"" & htmlEscape(ourls) & "\">" & names & "</A><BR>\n"
+  return op.handle.sendData(line)
+
+proc onSendChunk(op: GopherHandle, previ: int): bool =
+  var i = previ
+  var lasti = 0
+  while i < op.buffer.len:
+    if op.buffer[i] in {'\r', '\n'}:
+      if not op.flushLine(op.buffer, lasti, i):
+        return false
+      while i < op.buffer.high and op.buffer[i] in {'\r', '\n'}:
+        inc i
+      lasti = i
+    inc i
+  if lasti > 0:
+    op.buffer.delete(0 .. lasti)
+  return true
+
+# From the documentation: size is always 1.
+proc curlWriteBody(p: cstring, size: csize_t, nmemb: csize_t,
+    userdata: pointer): csize_t {.cdecl.} =
+  let op = cast[GopherHandle](userdata)
+  if not op.statusline:
+    op.statusline = true
+    if not op.onStatusLine():
+      return 0
+  if nmemb > 0:
+    if op.t in {DIRECTORY, SEARCH}:
+      let i = op.buffer.len
+      op.buffer.setLen(op.buffer.len + int(nmemb))
+      prepareMutation(op.buffer)
+      copyMem(addr op.buffer[i], addr p[0], nmemb)
+      if not op.onSendChunk(i):
+        return 0
+    else:
+      if not op.handle.sendData(p, int(nmemb)):
+        return 0
+  return nmemb
+
+proc finish(op: CurlHandle) =
+  let op = cast[GopherHandle](op)
+  if op.ispre:
+    discard op.handle.sendData("</PRE>\n")
+  discard op.handle.sendData("</BODY>\n</HTML>\n")
+
+proc loadGopher*(handle: LoaderHandle, curlm: CURLM,
+    request: Request): CurlHandle =
+  let curl = curl_easy_init()
+  doAssert curl != nil
+  if request.httpmethod != HTTP_GET:
+    discard handle.sendResult(int(ERROR_INVALID_METHOD))
+    return nil
+  var url = request.url
+  var path = url.pathname
+  if path.len < 1:
+    path &= '/'
+  if path.len < 2:
+    path &= '1'
+    url = newURL(url)
+    url.setPathname(path)
+  let t = gopherType(path[1])
+  let op = curl.newGopherHandle(request, handle, t)
+  if t == SEARCH:
+    if url.query.isNone:
+      op.surl = url.serialize()
+      op.loadSearch()
+      return nil
+    else:
+      url.query = some(url.query.get.after('='))
+  let surl = url.serialize()
+  if t in {DIRECTORY, SEARCH}:
+    op.surl = surl
+    op.finish = finish
+  curl.setopt(CURLOPT_URL, surl)
+  curl.setopt(CURLOPT_WRITEDATA, op)
+  curl.setopt(CURLOPT_WRITEFUNCTION, curlWriteBody)
+  if request.proxy != nil:
+    let purl = request.proxy.serialize()
+    curl.setopt(CURLOPT_PROXY, purl)
+  let res = curl_multi_add_handle(curlm, curl)
+  if res != CURLM_OK:
+    discard handle.sendResult(int(res))
+    return nil
+  return op
diff --git a/src/loader/headers.nim b/src/loader/headers.nim
index b02f30df..e8ef5084 100644
--- a/src/loader/headers.nim
+++ b/src/loader/headers.nim
@@ -64,6 +64,16 @@ func newHeaders(obj = none(HeadersInit)): Headers {.jsctor.} =
     headers.fill(obj.get)
   return headers
 
+func newHeaders*(table: openArray[(string, string)]): Headers =
+  let headers = Headers()
+  for (k, v) in table:
+    let k = k.toHeaderCase()
+    if k in headers.table:
+      headers.table[k].add(v)
+    else:
+      headers.table[k] = @[v]
+  return headers
+
 func newHeaders*(table: Table[string, string]): Headers =
   let headers = Headers()
   for k, v in table:
diff --git a/src/loader/loader.nim b/src/loader/loader.nim
index 7ccd9a7f..663915fa 100644
--- a/src/loader/loader.nim
+++ b/src/loader/loader.nim
@@ -34,6 +34,7 @@ import loader/curlhandle
 import loader/data
 import loader/file
 import loader/ftp
+import loader/gopher
 import loader/headers
 import loader/http
 import loader/loaderhandle
@@ -119,6 +120,10 @@ proc loadResource(ctx: LoaderContext, request: Request, handle: LoaderHandle) =
     let handleData = handle.loadFtp(ctx.curlm, request)
     if handleData != nil:
       ctx.handleList.add(handleData)
+  of "gopher", "gophers":
+    let handleData = handle.loadGopher(ctx.curlm, request)
+    if handleData != nil:
+      ctx.handleList.add(handleData)
   else:
     discard handle.sendResult(ERROR_UNKNOWN_SCHEME)
     handle.close()
author	bptato <nincsnevem662@gmail.com>	2023-09-20 01:12:46 +0200
committer	bptato <nincsnevem662@gmail.com>	2023-09-20 01:14:15 +0200
commit	ecfdd90f7947b65db1046cb2eeeaa8f1953b119f (patch)
tree	be0cc64cc1a3138c8d83205e1284309406ce96aa /src/loader
parent	a0f3631cc7373b513fa1ae2e9523b1db9dfc6eee (diff)
download	chawan-ecfdd90f7947b65db1046cb2eeeaa8f1953b119f.tar.gz