stream: There is no _read cb, there is only push

This makes it so that `stream.push(chunk)` is the only way to signal the
end of reading, removing the confusing disparity between the
callback-style _read method, and the fact that most real-world streams
do not have a 1:1 corollation between the "please give me data" event,
and the actual arrival of a chunk of data.

It is still possible, of course, to implement a `CallbackReadable` on
top of this.  Simply provide a method like this as the callback:

    function readCallback(er, chunk) {
      if (er)
        stream.emit('error', er);
      else
        stream.push(chunk);
    }

However, *only* fs streams actually would behave in this way, so it
makes not a lot of sense to make TCP, TLS, HTTP, and all the rest have
to bend into this uncomfortable paradigm.

1 files changed, 8 insertions, 6 deletions

diff --git a/lib/tls.js b/lib/tls.js
index 2a780373a..bb0a03af2 100644
--- a/lib/tls.js
+++ b/lib/tls.js
@@ -381,12 +381,13 @@ CryptoStream.prototype._writePending = function writePending() {
 };
 
 
-CryptoStream.prototype._read = function read(size, cb) {
+CryptoStream.prototype._read = function read(size) {
   // XXX: EOF?!
-  if (!this.pair.ssl) return cb(null, null);
+  if (!this.pair.ssl) return this.push(null);
 
   // Wait for session to be resumed
-  if (this._resumingSession || !this._reading) return cb(null, '');
+  // Mark that we're done reading, but don't provide data or EOF
+  if (this._resumingSession || !this._reading) return this.push('');
 
   var out;
   if (this === this.pair.cleartext) {
@@ -441,11 +442,12 @@ CryptoStream.prototype._read = function read(size, cb) {
       if (this === this.pair.cleartext)
         this._opposite._done();
 
-      return cb(null, null);
+      // EOF
+      return this.push(null);
     }
 
     // Bail out
-    return cb(null, '');
+    return this.push('');
   }
 
   // Give them requested data
@@ -459,7 +461,7 @@ CryptoStream.prototype._read = function read(size, cb) {
       self.read(bytesRead);
     });
   }
-  return cb(null, pool.slice(start, start + bytesRead));
+  return this.push(pool.slice(start, start + bytesRead));
 };