From aa063173f3d86d7b2a29e77e7ab7f99dc4ab053e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pavel=20Rosick=C3=BD?= <pavel.rosicky@easy.cz>
Date: Tue, 28 Mar 2017 23:58:47 +0200
Subject: [PATCH] net/imap: Replace TCPSocket.open with Socket.tcp and
 sock.gets, sock.read with sock.read_nonblock

---
 lib/net/imap.rb | 44 ++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 40 insertions(+), 4 deletions(-)

diff --git a/lib/net/imap.rb b/lib/net/imap.rb
index 7a4d4da301..ee878c8415 100644
--- a/lib/net/imap.rb
+++ b/lib/net/imap.rb
@@ -18,6 +18,7 @@
 require "monitor"
 require "digest/md5"
 require "strscan"
+require 'net/protocol'
 begin
   require "openssl"
 rescue LoadError
@@ -221,6 +222,16 @@ class IMAP
     # Returns all response handlers.
     attr_reader :response_handlers
 
+    # Seconds to wait until a connection is opened.
+    # If the IMAP object cannot open a connection within this time,
+    # it raises a Net::OpenTimeout exception. The default value is 30 seconds.
+    attr_reader :open_timeout
+
+    # Seconds to wait until reading one block (by one read(1) call).
+    # If the IMAP object cannot complete a read() within this time,
+    # it raises a Net::ReadTimeout exception. The default value is 60 seconds.
+    attr_reader :read_timeout
+
     # The thread to receive exceptions.
     attr_accessor :client_thread
 
@@ -1048,6 +1059,8 @@ def self.format_datetime(time)
     #         be installed.
     #         If options[:ssl] is a hash, it's passed to
     #         OpenSSL::SSL::SSLContext#set_params as parameters.
+    # open_timeout:: Seconds to wait until a connection is opened
+    # read_timeout:: Seconds to wait until reading one block
     #
     # The most common errors are:
     #
@@ -1076,8 +1089,10 @@ def initialize(host, port_or_options = {},
       @port = options[:port] || (options[:ssl] ? SSL_PORT : PORT)
       @tag_prefix = "RUBY"
       @tagno = 0
+      @open_timeout = options[:open_timeout] || 30
+      @read_timeout = options[:read_timeout] || 60
       @parser = ResponseParser.new
-      @sock = TCPSocket.open(@host, @port)
+      @sock = Socket.tcp(@host, @port, :connect_timeout => @open_timeout)
       begin
         if options[:ssl]
           start_tls_session(options[:ssl])
@@ -1199,14 +1214,35 @@ def get_tagged_response(tag, cmd)
       end
     end
 
+    def get_response_data(length, terminator = nil)
+      str = nil
+      buff = String.new
+      while true
+        str = @sock.read_nonblock(length, :exception => false)
+        case str
+        when :wait_readable
+          @sock.to_io.wait_readable(@read_timeout) or
+            raise Net::ReadTimeout, "#{@host}:#{@port} read timeout (exceeds #{@read_timeout} seconds)"
+        when nil
+          break
+        else
+          buff.concat(str)
+          if terminator ? buff.include?(terminator) : (buff.length >= length)
+            break
+          end
+        end
+      end
+      buff
+    end
+
     def get_response
       buff = String.new
       while true
-        s = @sock.gets(CRLF)
-        break unless s
+        s = get_response_data(1, CRLF)
+        break if s.length == 0
         buff.concat(s)
         if /\{(\d+)\}\r\n/n =~ s
-          s = @sock.read($1.to_i)
+          s = get_response_data($1.to_i)
           buff.concat(s)
         else
           break
-- 
2.11.0.windows.3