Fix parsing of responses to HEAD requests with non-zero Content-Length (

#225)

Sources/KituraNet/ClientRequest.swift

@@ -336,7 +336,8 @@ public class ClientRequest {
 
  let invoker = CurlInvoker(handle: handle!, maxRedirects: maxRedirects)
  invoker.delegate = self
- response = ClientResponse()
+ let skipBody = (method.uppercased() == "HEAD")
+ response = ClientResponse(skipBody: skipBody)
 
  var code = invoker.invoke()
  guard code == CURLE_OK else {

Sources/KituraNet/ClientResponse.swift

@@ -47,7 +47,7 @@ public class ClientResponse {
  private static let bufferSize = 2000
 
  /// The http_parser Swift wrapper
- private var httpParser = HTTPParser(isRequest: false)
+ private var httpParser: HTTPParser
 
  /// State of response parsing
  private var parserStatus = HTTPParserStatus()
@@ -71,7 +71,7 @@ public class ClientResponse {
  if parserStatus.state == .reset {
  reset()
  }
- 
+
  let bytes = buffer.bytes.assumingMemoryBound(to: Int8.self) + from
  let (numberParsed, _) = httpParser.execute(bytes, length: length)
 
@@ -155,7 +155,8 @@ public class ClientResponse {
  }
 
  /// Initializes a `ClientResponse` instance
- init() {
+ init(skipBody: Bool = false) {
+ httpParser = HTTPParser(isRequest: false, skipBody: skipBody)
  }
 
  /// The HTTP Status code, as an Int, sent in the response by the remote server.

Sources/KituraNet/HTTPParser/HTTPParser.swift

@@ -63,9 +63,10 @@ class HTTPParser {
  /// Initializes a HTTPParser instance
  ///
  /// - Parameter isRequest: whether or not this HTTP message is a request
+ /// - Parameter skipBody: whether parser should skip body content (ie when parsing the response to a HEAD request)
  ///
  /// - Returns: an HTTPParser instance
- init(isRequest: Bool) {
+ init(isRequest: Bool, skipBody: Bool = false) {
 
  self.isRequest = isRequest
 
@@ -99,14 +100,21 @@ class HTTPParser {
  return 0
  }
 
- settings.on_headers_complete = { (parser) -> Int32 in
- let method = String(cString: get_method(parser))
-
- let results = getResults(parser)
-
- results?.onHeadersComplete(method: method, versionMajor: (parser?.pointee.http_major)!,
- versionMinor: (parser?.pointee.http_minor)!)
- return 0
+ // Callback should return 1 when instructing the C HTTP parser
+ // to skip body content. This closure is bound to a C function
+ // pointer and cannot capture values (including self.skipBody)
+ // so instead we choose which closure to assign outside the
+ // closure.
+ if skipBody {
+ settings.on_headers_complete = { (parser) -> Int32 in
+ onHeadersComplete(parser)
+ return 1
+ }
+ } else {
+ settings.on_headers_complete = { (parser) -> Int32 in
+ onHeadersComplete(parser)
+ return 0
+ }
  }
 
  settings.on_message_complete = { (parser) -> Int32 in
@@ -116,7 +124,7 @@ class HTTPParser {
 
  reset() 
  }
- 
+
  /// Executes the parsing on the byte array
  ///
  /// - Parameter data: pointer to a byte array
@@ -146,6 +154,16 @@ class HTTPParser {
  }
 }
 
+fileprivate func onHeadersComplete(_ parser: UnsafeMutableRawPointer?) {
+ let httpParser = parser?.assumingMemoryBound(to: http_parser.self)
+ let method = String(cString: get_method(httpParser!))
+
+ let results = getResults(httpParser)
+
+ results?.onHeadersComplete(method: method, versionMajor: (httpParser?.pointee.http_major)!,
+ versionMinor: (httpParser?.pointee.http_minor)!)
+}
+
 fileprivate func getResults(_ parser: UnsafeMutableRawPointer?) -> ParseResults? {
  let httpParser = parser?.assumingMemoryBound(to: http_parser.self)
  let httpParserData = httpParser?.pointee.data

Tests/KituraNetTests/ClientE2ETests.swift

@@ -311,9 +311,7 @@ class ClientE2ETests: KituraNetTest {
  response.statusCode = .OK
  XCTAssertEqual(response.statusCode, .OK, "Set response status code wasn't .OK, it was \(String(describing: response.statusCode))")
  response.headers["Content-Type"] = ["text/plain"]
- if request.method.lowercased() != "head" {
- response.headers["Content-Length"] = ["\(result.characters.count)"]
- }
+ response.headers["Content-Length"] = ["\(result.characters.count)"]
 
  try response.end(text: result)
  }