Merge pull request #6752 from CyberShadow/pull-20181105-211026

Fix Issue 19367 - std.net.curl does not understand HTTP/2 status lines
merged-on-behalf-of: Vladimir Panteleev <github@thecybershadow.net>

std/net/curl.d

@@ -2385,7 +2385,6 @@ struct HTTP
                                                      in char[] value) callback)
         {
             import std.algorithm.searching : startsWith;
-            import std.conv : to;
             import std.regex : regex, match;
             import std.uni : toLower;
 
@@ -2405,18 +2404,8 @@ struct HTTP
                     if (header.startsWith("HTTP/"))
                     {
                         headersIn.clear();
-
-                        const m = match(header, regex(r"^HTTP/(\d+)\.(\d+) (\d+) (.*)$"));
-                        if (m.empty)
-                        {
-                            // Invalid status line
-                        }
-                        else
+                        if (parseStatusLine(header, status))
                         {
-                            status.majorVersion = to!ushort(m.captures[1]);
-                            status.minorVersion = to!ushort(m.captures[2]);
-                            status.code = to!ushort(m.captures[3]);
-                            status.reason = m.captures[4].idup;
                             if (onReceiveStatusLine != null)
                                 onReceiveStatusLine(status);
                         }
@@ -2452,6 +2441,37 @@ struct HTTP
     private RefCounted!Impl p;
     import etc.c.curl : CurlTimeCond;
 
+    /// Parse status line, as received from / generated by cURL.
+    private static bool parseStatusLine(in char[] header, out StatusLine status) @safe
+    {
+        import std.conv : to;
+        import std.regex : regex, match;
+
+        const m = match(header, regex(r"^HTTP/(\d+)(?:\.(\d+))? (\d+)(?: (.*))?$"));
+        if (m.empty)
+            return false; // Invalid status line
+        else
+        {
+            status.majorVersion = to!ushort(m.captures[1]);
+            status.minorVersion = m.captures[2].length ? to!ushort(m.captures[2]) : 0;
+            status.code = to!ushort(m.captures[3]);
+            status.reason = m.captures[4].idup;
+            return true;
+        }
+    }
+
+    @safe unittest
+    {
+        StatusLine status;
+        assert(parseStatusLine("HTTP/1.1 200 OK", status)
+            && status == StatusLine(1, 1, 200, "OK"));
+        assert(parseStatusLine("HTTP/1.0 304 Not Modified", status)
+            && status == StatusLine(1, 0, 304, "Not Modified"));
+        // The HTTP2 protocol is binary; cURL generates this fake text header.
+        assert(parseStatusLine("HTTP/2 200", status)
+            && status == StatusLine(2, 0, 200, null));
+    }
+
     /** Time condition enumeration as an alias of $(REF CurlTimeCond, etc,c,curl)
 
         $(HTTP www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.25, _RFC2616 Section 14.25)