Add some features and change all types unit to byte

lib/constructor.js

@@ -64,7 +64,10 @@ function size_of(segments, bindings) {
 
 function writeInteger(segment, buf, offset, bindings) {
   var value = (segment.name) ? bindings[segment.name] : segment.value;
-  var size = segment.size * segment.unit;
+  var size = segment.size * segment.unit, mod = segment.mod;
+  if(mod){
+    value = value * Math.pow(10, mod);
+  }
   switch (size) {
   case 8:
     buf.writeUInt8(value, offset);

lib/grammar.pegjs

@@ -59,9 +59,12 @@ specifierTail
 specifier
     = 'little' / 'big' / 'signed' / 'unsigned'
     / 'integer' / 'binary' / 'float'
-    / unit
+    / unit / mod
 
 unit
     = 'unit:' num:number { return 'unit:' + num; }
 
+mod
+    = 'mod:' num:number { return 'mod:' + num; }
+
 ws = [ \t\n]*

lib/interp.js

@@ -112,16 +112,21 @@ function match(pattern, binary, boundvars) {
   function get_integer(segment) {
     debug("get_integer"); debug(segment);
     // let's do only multiples of eight bits for now
-    var unit = segment.unit, size = size_of(segment, vars);
+    var unit = segment.unit, size = size_of(segment, vars), mod = segment.mod;
     var bitsize = size * unit;
     var byteoffset = offset / 8; // NB assumes aligned
     offset += bitsize;
     if (bitsize % 8 > 0 || (offset > binsize)) {
       return false;
     }
     else {
-      return parse_int(binary, byteoffset, bitsize,
+      num = parse_int(binary, byteoffset, bitsize,
                        segment.bigendian, segment.signed);
+      if(mod){
+        return (num * Math.pow(0.1, mod)).toFixed(mod);
+      } else {
+        return num;
+      }
     }
   }
 

lib/pattern.js

@@ -58,6 +58,7 @@ function specs(segment, type, specifiers) {
   switch (type) {
   case 'integer':
     segment.signed = signed_in(specifiers);
+    segment.mod = mod_in(specifiers);
     // fall through
   case 'float':
     segment.bigendian = endian_in(specifiers);
@@ -89,23 +90,32 @@ function unit_in(specifiers, type) {
   // OK defaults then
   switch (type) {
   case 'binary':
-    return 8;
   case 'integer':
   case 'float':
-    return 1;
+    return 8;
   }
 }
 
+function mod_in(specifiers) {
+  for (var s in specifiers) {
+    if (s.substr(0, 4) == 'mod:') {
+      var mod = parseInt(s.substr(4));
+      return mod;
+    }
+  }
+  return 0;
+}
+
 function size_of(segment, type, size, unit) {
   if (size !== undefined && size !== '') {
     return size;
   }
   else {
     switch (type) {
     case 'integer':
-      return 8;
+      return 1;
     case 'float':
-      return 64;
+      return 8;
     case 'binary':
       return true;
     }