From a75010e2cc9a8a7956f4fa04c0fb60597ec78b62 Mon Sep 17 00:00:00 2001
From: Tino Lange <tino@tino-lange.de>
Date: Tue, 9 Jun 2015 20:38:12 +0200
Subject: [PATCH]  - high-level wrapper: make {in,de}flate.push(data,
 Z_SYNC_FLUSH) working    (will fix issue #34)

---
 lib/deflate.js | 10 +++++++++-
 lib/inflate.js | 10 +++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/lib/deflate.js b/lib/deflate.js
index 9cd0392..625ec67 100644
--- a/lib/deflate.js
+++ b/lib/deflate.js
@@ -17,6 +17,7 @@ var Z_FINISH        = 4;
 
 var Z_OK            = 0;
 var Z_STREAM_END    = 1;
+var Z_SYNC_FLUSH    = 2;
 
 var Z_DEFAULT_COMPRESSION = -1;
 
@@ -224,7 +225,7 @@ Deflate.prototype.push = function(data, mode) {
       this.ended = true;
       return false;
     }
-    if (strm.avail_out === 0 || (strm.avail_in === 0 && _mode === Z_FINISH)) {
+    if (strm.avail_out === 0 || (strm.avail_in === 0 && (_mode === Z_FINISH || _mode === Z_SYNC_FLUSH))) {
       if (this.options.to === 'string') {
         this.onData(strings.buf2binstring(utils.shrinkBuf(strm.output, strm.next_out)));
       } else {
@@ -241,6 +242,13 @@ Deflate.prototype.push = function(data, mode) {
     return status === Z_OK;
   }
 
+  // callback interim results if Z_SYNC_FLUSH.
+  if (_mode === Z_SYNC_FLUSH) {
+    this.onEnd(Z_OK);
+    strm.avail_out = 0;
+    return true;
+  }
+
   return true;
 };
 
diff --git a/lib/inflate.js b/lib/inflate.js
index 96915bc..b271035 100644
--- a/lib/inflate.js
+++ b/lib/inflate.js
@@ -207,7 +207,7 @@ Inflate.prototype.push = function(data, mode) {
     }
 
     if (strm.next_out) {
-      if (strm.avail_out === 0 || status === c.Z_STREAM_END || (strm.avail_in === 0 && _mode === c.Z_FINISH)) {
+      if (strm.avail_out === 0 || status === c.Z_STREAM_END || (strm.avail_in === 0 && (_mode === c.Z_FINISH || _mode === c.Z_SYNC_FLUSH))) {
 
         if (this.options.to === 'string') {
 
@@ -233,6 +233,7 @@ Inflate.prototype.push = function(data, mode) {
   if (status === c.Z_STREAM_END) {
     _mode = c.Z_FINISH;
   }
+
   // Finalize on the last chunk.
   if (_mode === c.Z_FINISH) {
     status = zlib_inflate.inflateEnd(this.strm);
@@ -241,6 +242,13 @@ Inflate.prototype.push = function(data, mode) {
     return status === c.Z_OK;
   }
 
+  // callback interim results if Z_SYNC_FLUSH.
+  if (_mode === c.Z_SYNC_FLUSH) {
+    this.onEnd(c.Z_OK);
+    strm.avail_out = 0;
+    return true;
+  }
+
   return true;
 };