bitsyntax - npm Package Compare versions

Comparing version 0.0.3 to 0.0.4

index.js

@@ -0,1 +1,3 @@
+'use strict';
+
 module.exports.parse = require('./lib/parse').parse;
@@ -2,0 +4,0 @@ module.exports.match = require('./lib/interp').match;

lib/compile.js

@@ -1,3 +0,5 @@
-// Compile patterns to recognisers
+// Compile patterns to recognisers and constructors
 
+'use strict';
+
 require('buffer-more-ints');
@@ -107,9 +109,16 @@ var $ = require('util').format;
     }
-    $line("if (result === false) { return false; }");
+    $line("if (result === false) return false;");
     if (segment.name) {
-      $line("else { %s = result; }", var_name(segment.name));
+      // variable is given a value in the environment
+      $line("else if (%s !== undefined) {", var_name(segment.name));
+      // .. and it is not the same as that matched
+      $line("if (%s != result) return false;",
+            var_name(segment.name));
+      $line("}");
+      // variable is free
+      $line('else %s = result;', var_name(segment.name));
     }
     else {
       var repr = JSON.stringify(segment.value);
-      $line("else if (result != %s) { return false; }", repr);
+      $line("else if (result != %s) return false;", repr);
     }
@@ -126,3 +135,3 @@ }
   for (var i = 0; i < segments.length; i++) {
-    name = segments[i].name;
+    var name = segments[i].name;
     if (name && name !== '_') {
@@ -141,11 +150,11 @@ names[name] = true;
   $start();
-  $line("return function(binary, vars) {");
-  $line("var bin = binary, scope = vars || {};");
+  $line("return function(binary, env) {");
+  $line("'use strict';");
+  $line("var bin = binary, env = env || {};");
   $line("var offset = 0, binsize = bin.length * 8;");
   $line("var bits, result, byteoffset;");
   var varnames = variables(segments);
-  var bindings = "";
   for (var v = 0; v < varnames.length; v++) {
     var name = varnames[v];
-    $line("var %s = scope['%s'];", var_name(name), name);
+    $line("var %s = env['%s'];", var_name(name), name);
   }
@@ -161,3 +170,3 @@
   $line("if (offset == binsize) {");
-  $line("var bindings = {");
+  $line("return {");
   for (var v = 0; v < varnames.length; v++) {
@@ -167,5 +176,5 @@ var name = varnames[v];
   }
-  $line('}');
-  $line("return bindings; }");
-  $line("else { return false; }");
+  $line('};');
+  $line('}'); // if offset == binsize
+  $line("else return false;");
   $line("}"); // end function
@@ -220,3 +229,2 @@
   else {
-    // could do this statically of course
     $line('size = %d;', (segment.size * segment.unit) / 8);
@@ -263,6 +271,3 @@ }
 
-function compile_write(segments) {
-  $start();
-
-  $line('return function(buf, offset, bindings) {');  
+function emit_write(segments) {
   $line('var val, size;');
@@ -276,20 +281,17 @@
   }
-
-  $line('return offset;');
-  $line('}'); // end function
-  var fn = new Function('write_int', 'write_float', $result());
-  return fn(write_int, write_float);
 }
 
 function compile_ctor(segments) {
-  var writer = compile_write(segments);
   $start();
   $line('return function(bindings) {');
+  $line("'use strict';");
   size_of(segments);
   $line('var buf = new Buffer(buffersize);');
-  $line('write(buf, 0, bindings);');
+  $line('var offset = 0;');
+  emit_write(segments);
   $line('return buf;');
   $line('}'); // end function
 
-  return new Function('write', $result())(writer);
+  return new Function('write_int', 'write_float',
+                      $result())(write_int, write_float);
 }
@@ -303,3 +305,2 @@
 };
-module.exports.compile_write = compile_write;
 module.exports.compile_builder = function() {
@@ -306,0 +307,0 @@ var str = [].join.call(arguments, ',');

lib/constructor.js

@@ -5,2 +5,4 @@ // -*- js-indent-level: 2 -*-
 
+'use strict';
+
 var ints = require('buffer-more-ints');
@@ -7,0 +9,0 @@

lib/interp.js

@@ -34,2 +34,4 @@ // -*- js-indent: 2 -*-
 
+'use strict';
+
 var ints = require('buffer-more-ints');
@@ -36,0 +38,0 @@

lib/parse.js

 // Parse patterns in string form into the form we use for interpreting
 // (and later, for compiling).
 
+'use strict';
+
 var ast = require('./pattern');
@@ -5,0 +7,0 @@ var parser = require('./parser');

lib/pattern.js

 // -*- js-indent-level: 2 -*-
 // Constructing patterns
 
+'use strict';
+
 function set(values) {
@@ -5,0 +7,0 @@ var s = {};

package.json

@@ -8,3 +8,3 @@ {
   "description": "Pattern-matching on byte buffers",
-  "version": "0.0.3",
+  "version": "0.0.4",
   "repository": {
@@ -27,4 +27,4 @@ "type": "git",
     "pegjs": "0.7.x",
-    "mocha": "0.9.x"
+    "mocha": "1.x"
   }
 }

README.md

@@ -59,4 +59,4 @@ # Byte-wise matching for Node.JS
 return either a map of bindings, or `false`, given a buffer and
-optionally an environment. The environment contains values for the
-bound variables in the pattern (if there are any).
+optionally an environment. The environment contains values for bound
+variables in the pattern (if there are any).
 
@@ -75,4 +75,4 @@ ```js
 ```js
-var p = bitsyntax.matcher('"foo:", str/binary');
-p(new Buffer("bar:humbug"));
+var p = bitsyntax.matcher('"foo=", str/binary');
+p(new Buffer("bar=humbug"));
 // => false
@@ -166,3 +166,5 @@ ```
 will be bound to that variable name for the rest of the pattern. If a
-literal value is given, the matched value must equal that value.
+literal value is given, the matched value must equal that value. If a
+variable's value is given in the environment, the matched value must
+equal the provided value.
 
@@ -261,4 +263,4 @@ When used in a builder, the literal value will be copied into the
 
-When used in a builder, a quoted string is copied verbatim into the
-result.
+When used in a builder, a quoted string is copied into the result as
+the bytes of its UTF8 encoding.
 
@@ -304,1 +306,6 @@ ## Examples
 remaining (possibly zero-length) binary as `rest`.
+
+    s:8, key:s/binary, value/binary
+
+When given the environment `{s:6, key: "foobar"}`, will match a binary
+starting with [6, 0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72, ...].

New alerts

Uses eval

Supply chain risk

Package uses eval() which is a dangerous function. This prevents the code from running in certain environments and increases the risk that the code may contain exploits or malicious behavior.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Fixed alerts

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Uses eval

Supply chain risk

Package uses eval() which is a dangerous function. This prevents the code from running in certain environments and increases the risk that the code may contain exploits or malicious behavior.

Found 1 instance in 1 package

Environment variable access

Supply chain risk

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

75367

increased by0.67%

Lines of code

2059

increased by0.34%

Number of lines in readme file

307

increased by2.33%

Number of medium supply chain risk alerts

2

decreased by-50%

Worsened metrics

Number of low supply chain risk alerts

2

increased by100%

No dependency changes