better docs/works with errors/messages

lib/deflate.js

@@ -45,12 +45,19 @@ function sliceBuf(buf, size) {
  * custom handlers.
  **/
 
+/**
+ * Deflate.msg -> String
+ *
+ * Error message, if [[Deflate.err]] != 0
+ **/
+
 
 /**
  * new Deflate(options)
  * - options (Object): zlib deflate options.
  *
- * Creates new deflator instance with specified params. Supported options:
+ * Creates new deflator instance with specified params. Throws exception
+ * on bad params. Supported options:
  *
  * - `level`
  * - `windowBits`
@@ -104,8 +111,10 @@ var Deflate = function(options) {
     opt.windowBits += 16;
   }
 
-  this.ended = false; // used to avoid multiple onEnd() calls
-  this.chunks = [];   // chunks of compressed data
+  this.err    = 0;      // error code, if happens (0 = Z_OK)
+  this.msg    = '';     // error message
+  this.ended  = false;  // used to avoid multiple onEnd() calls
+  this.chunks = [];     // chunks of compressed data
 
   this.strm = new zstream();
 
@@ -224,8 +233,7 @@ Deflate.prototype.onEnd = function(status) {
   }
   this.chunks = [];
   this.err = status;
-  // TODO: detect message by status, if not set in zstream
-  this.msg = this.strm.msg || msg[status];
+  this.msg = msg[status];
 };
 
 

lib/inflate.js

@@ -43,12 +43,19 @@ function sliceBuf(buf, size) {
  * Should be checked if broken data possible.
  **/
 
+/**
+ * Inflate.msg -> String
+ *
+ * Error message, if [[Inflate.err]] != 0
+ **/
+
 
 /**
  * new Inflate(options)
  * - options (Object): zlib inflate options.
  *
- * Creates new inflator instance with specified params. Supported options:
+ * Creates new inflator instance with specified params. Throws exception
+ * on bad params. Supported options:
  *
  * - `windowBits`
  *
@@ -90,12 +97,14 @@ var Inflate = function(options) {
     opt.windowBits = -opt.windowBits;
   }
 
-  this.ended = false; // used to avoid multiple onEnd() calls
-  this.chunks = [];   // chunks of compressed data
+  this.err    = 0;      // error code, if happens (0 = Z_OK)
+  this.msg    = '';     // error message
+  this.ended  = false;  // used to avoid multiple onEnd() calls
+  this.chunks = [];     // chunks of compressed data
 
-  this.strm = new zstream();
+  this.strm   = new zstream();
 
-  var status = zlib_inflate.inflateInit2(
+  var status  = zlib_inflate.inflateInit2(
     this.strm,
     opt.windowBits
   );
@@ -206,8 +215,7 @@ Inflate.prototype.onEnd = function(status) {
   }
   this.chunks = [];
   this.err = status;
-  // TODO: detect message by status, if not set in zstream
-  this.msg = this.strm.msg || msg[status];
+  this.msg = msg[status];
 };
 
 

lib/zlib/zstream.js

@@ -2,6 +2,7 @@
 
 var c = require('constants');
 
+// TODO: remove Z_NULL. Set proper values directly
 function ZStream() {
   /* next input byte */
   this.next_in = c.Z_NULL;