js/Name.js - ndn-js - Gitiles

 /**
  * @author: Meki Cheraoui, Jeff Thompson
  * See COPYING for copyright and distribution information.
  * This class represents a Name as an array of components where each is a byte array.
  */

 /*
  * Create a new Name from _components.
  * If _components is a string, parse it as a URI.  Otherwise it is an array of components
  * where each is a string, byte array, ArrayBuffer or Uint8Array.
  * Convert and store as an array of Uint8Array.
  * If a component is a string, encode as utf8.
  */
 var Name = function Name(_components){
 	if( typeof _components == 'string') {
 		if(LOG>3)console.log('Content Name String '+_components);
 		this.components = Name.createNameArray(_components);
 	}
 	else if(typeof _components === 'object'){
 		if(LOG>4)console.log('Content Name Array '+_components);
 		this.components = [];
         for (var i = 0; i < _components.length; ++i)
             this.add(_components[i]);
 	}
 	else if(_components==null)
 		this.components =[];
 	else
 		if(LOG>1)console.log("NO CONTENT NAME GIVEN");
 };

 Name.prototype.getName = function() {
     return this.to_uri();
 };

 /* Parse name as a URI and return an array of Uint8Array components.
  *
  */
 Name.createNameArray = function(name) {
     name = name.trim();
     if (name.length <= 0)
         return [];

     var iColon = name.indexOf(':');
     if (iColon >= 0) {
         // Make sure the colon came before a '/'.
         var iFirstSlash = name.indexOf('/');
         if (iFirstSlash < 0 || iColon < iFirstSlash)
             // Omit the leading protocol such as ndn:
             name = name.substr(iColon + 1, name.length - iColon - 1).trim();
     }

   	if (name[0] == '/') {
         if (name.length >= 2 && name[1] == '/') {
             // Strip the authority following "//".
             var iAfterAuthority = name.indexOf('/', 2);
             if (iAfterAuthority < 0)
                 // Unusual case: there was only an authority.
                 return [];
             else
                 name = name.substr(iAfterAuthority + 1, name.length - iAfterAuthority - 1).trim();
         }
         else
             name = name.substr(1, name.length - 1).trim();
     }

 	var array = name.split('/');

     // Unescape the components.
     for (var i = 0; i < array.length; ++i) {
         var component = Name.fromEscapedString(array[i]);

         if (component == null) {
             // Ignore the illegal componenent.  This also gets rid of a trailing '/'.
             array.splice(i, 1);
             --i;
             continue;
         }
         else
             array[i] = component;
     }

 	return array;
 }


 Name.prototype.from_ccnb = function(/*XMLDecoder*/ decoder)  {
 		decoder.readStartElement(this.getElementLabel());


 		this.components = new Array(); //new ArrayList<byte []>();

 		while (decoder.peekStartElement(CCNProtocolDTags.Component)) {
 			this.add(decoder.readBinaryElement(CCNProtocolDTags.Component));
 		}

 		decoder.readEndElement();
 };

 Name.prototype.to_ccnb = function(/*XMLEncoder*/ encoder)  {

 		if( this.components ==null )
 			throw new Error("CANNOT ENCODE EMPTY CONTENT NAME");

 		encoder.writeStartElement(this.getElementLabel());
 		var count = this.components.length;
 		for (var i=0; i < count; i++) {
 			encoder.writeElement(CCNProtocolDTags.Component, this.components[i]);
 		}
 		encoder.writeEndElement();
 };

 Name.prototype.getElementLabel = function(){
 	return CCNProtocolDTags.Name;
 };

 /*
  * component is a string, byte array, ArrayBuffer or Uint8Array.
  * Convert to Uint8Array and add to this Name.
  * If a component is a string, encode as utf8.
  * Return the converted value.
  */
 Name.prototype.add = function(component){
     var result;
     if(typeof component == 'string') {
         result = DataUtils.stringToUtf8Array(component);
         this.components.push (result);
     }
     else if(typeof component == 'object' && component instanceof Uint8Array) {
         result = new Uint8Array(component);
         this.components.push (result);
     }
     else if(typeof component == 'object' && component instanceof ArrayBuffer) {
         // Make a copy.  Don't use ArrayBuffer.slice since it isn't always supported.
         result = new Uint8Array(new ArrayBuffer(component.byteLength));
         result.set(new Uint8Array(component));
         this.components.push(result);
     }
     else if(typeof component == 'object' && component instanceof Name) {
         components = component;
         if (this == component) {
             components = new Name (component.components); // special case, when we need to create a copy
         }
 	for(var i = 0; i < components.components.length; ++i) {
             result = new Uint8Array (components.components[i]);
             this.components.push (result);
         }
     }
     else if(typeof component == 'object') {
         // Assume component is a byte array.  We can't check instanceof Array because
         //   this doesn't work in JavaScript if the array comes from a different module.
         result = new Uint8Array(component);
         this.components.push(result);
     }
     else
 	throw new Error("Cannot add Name element at index " + this.components.length +
                         ": Invalid type");

     return this;
 };

 /**
  * @brief Add component that represents a segment number
  *
  * @param number Segment number (integer is expected)
  *
  * This component has a special format handling:
  * - if number is zero, then %00 is added
  * - if number is between 1 and 255, %00%01 .. %00%FF is added
  * - ...
  */
 Name.prototype.addSegment = function(number) {
     // step 1: figure out how many bytes will be needed
     var bytes = 1; // at least 1 byte
     var test_number = number;
     while (test_number > 0) {
         bytes ++;
         test_number >>= 8;
     }

     var result = new Uint8Array (bytes);
     var index = 0;
     result[index] = 0;
     index ++;
     while (number > 0) {
         result[index] = number & 0xFF;
         number >>= 8;
         index ++;
     }

     this.components.push(result);
     return this;
 }

 // Return the escaped name string according to "CCNx URI Scheme".
 Name.prototype.to_uri = function() {
     if (this.components.length == 0)
         return "/";

 	var result = "";

 	for(var i = 0; i < this.components.length; ++i)
 		result += "/"+ Name.toEscapedString(this.components[i]);

 	return result;
 };

 /*
  * Return a new Name with the first nComponents components of this Name.
  */
 Name.prototype.getPrefix = function(nComponents) {
     return new Name(this.components.slice(0, nComponents));
 }

 /*
  * Return a new ArrayBuffer of the component at i.
  */
 Name.prototype.getComponent = function(i) {
     var result = new ArrayBuffer(this.components[i].length);
     new Uint8Array(result).set(this.components[i]);
     return result;
 }

 /*
  * The "file name" in a name is the last component that isn't blank and doesn't start with one of the
  *   special marker octets (for version, etc.).  Return the index in this.components of
  *   the file name, or -1 if not found.
  */
 Name.prototype.indexOfFileName = function() {
     for (var i = this.components.length - 1; i >= 0; --i) {
         var component = this.components[i];
         if (component.length <= 0)
             continue;

         if (component[0] == 0 || component[0] == 0xC0 || component[0] == 0xC1 ||
             (component[0] >= 0xF5 && component[0] <= 0xFF))
             continue;

         return i;
     }

     return -1;
 }

 /*
  * Return true if this Name has the same components as name.
  */
 Name.prototype.equalsName = function(name) {
     if (this.components.length != name.components.length)
         return false;

     // Start from the last component because they are more likely to differ.
     for (var i = this.components.length - 1; i >= 0; --i) {
         if (!DataUtils.arraysEqual(this.components[i], name.components[i]))
             return false;
     }

     return true;
 }

 /*
  * Find the last component in name that has a ContentDigest and return the digest value as Uint8Array,
  *   or null if not found.  See Name.getComponentContentDigestValue.
  */
 Name.prototype.getContentDigestValue = function() {
     for (var i = this.components.length - 1; i >= 0; --i) {
         var digestValue = Name.getComponentContentDigestValue(this.components[i]);
         if (digestValue != null)
            return digestValue;
     }

     return null;
 }

 /*
  * If component is a ContentDigest, return the digest value as a Uint8Array subarray (don't modify!).
  * If not a ContentDigest, return null.
  * A ContentDigest component is Name.ContentDigestPrefix + 32 bytes + Name.ContentDigestSuffix.
  */
 Name.getComponentContentDigestValue = function(component) {
     var digestComponentLength = Name.ContentDigestPrefix.length + 32 + Name.ContentDigestSuffix.length;
     // Check for the correct length and equal ContentDigestPrefix and ContentDigestSuffix.
     if (component.length == digestComponentLength &&
         DataUtils.arraysEqual(component.subarray(0, Name.ContentDigestPrefix.length),
                               Name.ContentDigestPrefix) &&
         DataUtils.arraysEqual(component.subarray
            (component.length - Name.ContentDigestSuffix.length, component.length),
                               Name.ContentDigestSuffix))
        return component.subarray(Name.ContentDigestPrefix.length, Name.ContentDigestPrefix.length + 32);
    else
        return null;
 }

 // Meta GUID "%C1.M.G%C1" + ContentDigest with a 32 byte BLOB.
 Name.ContentDigestPrefix = new Uint8Array([0xc1, 0x2e, 0x4d, 0x2e, 0x47, 0xc1, 0x01, 0xaa, 0x02, 0x85]);
 Name.ContentDigestSuffix = new Uint8Array([0x00]);

 /*
  * Return component as an escaped string according to "CCNx URI Scheme".
  * We can't use encodeURIComponent because that doesn't encode all the characters we want to.
  */
 Name.toEscapedString = function(component) {
     var result = "";
     var gotNonDot = false;
     for (var i = 0; i < component.length; ++i) {
         if (component[i] != 0x2e) {
             gotNonDot = true;
             break;
         }
     }
     if (!gotNonDot) {
         // Special case for component of zero or more periods.  Add 3 periods.
         result = "...";
         for (var i = 0; i < component.length; ++i)
             result += ".";
     }
     else {
         for (var i = 0; i < component.length; ++i) {
             var value = component[i];
             // Check for 0-9, A-Z, a-z, (+), (-), (.), (_)
             if (value >= 0x30 && value <= 0x39 || value >= 0x41 && value <= 0x5a ||
                 value >= 0x61 && value <= 0x7a || value == 0x2b || value == 0x2d ||
                 value == 0x2e || value == 0x5f)
                 result += String.fromCharCode(value);
             else
                 result += "%" + (value < 16 ? "0" : "") + value.toString(16).toUpperCase();
         }
     }
     return result;
 };

 /*
  * Return component as a Uint8Array by decoding the escapedString according to "CCNx URI Scheme".
  * If escapedString is "", "." or ".." then return null, which means to skip the component in the name.
  */
 Name.fromEscapedString = function(escapedString) {
     var component = unescape(escapedString.trim());

     if (component.match(/[^.]/) == null) {
         // Special case for component of only periods.
         if (component.length <= 2)
             // Zero, one or two periods is illegal.  Ignore this componenent to be
             //   consistent with the C implementation.
             return null;
         else
             // Remove 3 periods.
             return DataUtils.toNumbersFromString(component.substr(3, component.length - 3));
     }
     else
         return DataUtils.toNumbersFromString(component);
 }

 Name.prototype.match = function(/*Name*/ name) {
 	var i_name = this.components;
 	var o_name = name.components;

 	// The intrest name is longer than the name we are checking it against.
 	if (i_name.length > o_name.length)
             return false;

 	// Check if at least one of given components doesn't match.
     for (var i = 0; i < i_name.length; ++i) {
         if (!DataUtils.arraysEqual(i_name[i], o_name[i]))
             return false;
     }

 	return true;
 };
	/**
	* @author: Meki Cheraoui, Jeff Thompson
	* See COPYING for copyright and distribution information.
	* This class represents a Name as an array of components where each is a byte array.
	*/

	/*
	* Create a new Name from _components.
	* If _components is a string, parse it as a URI. Otherwise it is an array of components
	* where each is a string, byte array, ArrayBuffer or Uint8Array.
	* Convert and store as an array of Uint8Array.
	* If a component is a string, encode as utf8.
	*/
	var Name = function Name(_components){
	if( typeof _components == 'string') {
	if(LOG>3)console.log('Content Name String '+_components);
	this.components = Name.createNameArray(_components);
	}
	else if(typeof _components === 'object'){
	if(LOG>4)console.log('Content Name Array '+_components);
	this.components = [];
	for (var i = 0; i < _components.length; ++i)
	this.add(_components[i]);
	}
	else if(_components==null)
	this.components =[];
	else
	if(LOG>1)console.log("NO CONTENT NAME GIVEN");
	};

	Name.prototype.getName = function() {
	return this.to_uri();
	};

	/* Parse name as a URI and return an array of Uint8Array components.
	*
	*/
	Name.createNameArray = function(name) {
	name = name.trim();
	if (name.length <= 0)
	return [];

	var iColon = name.indexOf(':');
	if (iColon >= 0) {
	// Make sure the colon came before a '/'.
	var iFirstSlash = name.indexOf('/');
	if (iFirstSlash < 0 \|\| iColon < iFirstSlash)
	// Omit the leading protocol such as ndn:
	name = name.substr(iColon + 1, name.length - iColon - 1).trim();
	}

	if (name[0] == '/') {
	if (name.length >= 2 && name[1] == '/') {
	// Strip the authority following "//".
	var iAfterAuthority = name.indexOf('/', 2);
	if (iAfterAuthority < 0)
	// Unusual case: there was only an authority.
	return [];
	else
	name = name.substr(iAfterAuthority + 1, name.length - iAfterAuthority - 1).trim();
	}
	else
	name = name.substr(1, name.length - 1).trim();
	}

	var array = name.split('/');

	// Unescape the components.
	for (var i = 0; i < array.length; ++i) {
	var component = Name.fromEscapedString(array[i]);

	if (component == null) {
	// Ignore the illegal componenent. This also gets rid of a trailing '/'.
	array.splice(i, 1);
	--i;
	continue;
	}
	else
	array[i] = component;
	}

	return array;
	}


	Name.prototype.from_ccnb = function(/XMLDecoder/ decoder) {
	decoder.readStartElement(this.getElementLabel());


	this.components = new Array(); //new ArrayList<byte []>();

	while (decoder.peekStartElement(CCNProtocolDTags.Component)) {
	this.add(decoder.readBinaryElement(CCNProtocolDTags.Component));
	}

	decoder.readEndElement();
	};

	Name.prototype.to_ccnb = function(/XMLEncoder/ encoder) {

	if( this.components ==null )
	throw new Error("CANNOT ENCODE EMPTY CONTENT NAME");

	encoder.writeStartElement(this.getElementLabel());
	var count = this.components.length;
	for (var i=0; i < count; i++) {
	encoder.writeElement(CCNProtocolDTags.Component, this.components[i]);
	}
	encoder.writeEndElement();
	};

	Name.prototype.getElementLabel = function(){
	return CCNProtocolDTags.Name;
	};

	/*
	* component is a string, byte array, ArrayBuffer or Uint8Array.
	* Convert to Uint8Array and add to this Name.
	* If a component is a string, encode as utf8.
	* Return the converted value.
	*/
	Name.prototype.add = function(component){
	var result;
	if(typeof component == 'string') {
	result = DataUtils.stringToUtf8Array(component);
	this.components.push (result);
	}
	else if(typeof component == 'object' && component instanceof Uint8Array) {
	result = new Uint8Array(component);
	this.components.push (result);
	}
	else if(typeof component == 'object' && component instanceof ArrayBuffer) {
	// Make a copy. Don't use ArrayBuffer.slice since it isn't always supported.
	result = new Uint8Array(new ArrayBuffer(component.byteLength));
	result.set(new Uint8Array(component));
	this.components.push(result);
	}
	else if(typeof component == 'object' && component instanceof Name) {
	components = component;
	if (this == component) {
	components = new Name (component.components); // special case, when we need to create a copy
	}
	for(var i = 0; i < components.components.length; ++i) {
	result = new Uint8Array (components.components[i]);
	this.components.push (result);
	}
	}
	else if(typeof component == 'object') {
	// Assume component is a byte array. We can't check instanceof Array because
	// this doesn't work in JavaScript if the array comes from a different module.
	result = new Uint8Array(component);
	this.components.push(result);
	}
	else
	throw new Error("Cannot add Name element at index " + this.components.length +
	": Invalid type");

	return this;
	};

	/**
	* @brief Add component that represents a segment number
	*
	* @param number Segment number (integer is expected)
	*
	* This component has a special format handling:
	* - if number is zero, then %00 is added
	* - if number is between 1 and 255, %00%01 .. %00%FF is added
	* - ...
	*/
	Name.prototype.addSegment = function(number) {
	// step 1: figure out how many bytes will be needed
	var bytes = 1; // at least 1 byte
	var test_number = number;
	while (test_number > 0) {
	bytes ++;
	test_number >>= 8;
	}

	var result = new Uint8Array (bytes);
	var index = 0;
	result[index] = 0;
	index ++;
	while (number > 0) {
	result[index] = number & 0xFF;
	number >>= 8;
	index ++;
	}

	this.components.push(result);
	return this;
	}

	// Return the escaped name string according to "CCNx URI Scheme".
	Name.prototype.to_uri = function() {
	if (this.components.length == 0)
	return "/";

	var result = "";

	for(var i = 0; i < this.components.length; ++i)
	result += "/"+ Name.toEscapedString(this.components[i]);

	return result;
	};

	/*
	* Return a new Name with the first nComponents components of this Name.
	*/
	Name.prototype.getPrefix = function(nComponents) {
	return new Name(this.components.slice(0, nComponents));
	}

	/*
	* Return a new ArrayBuffer of the component at i.
	*/
	Name.prototype.getComponent = function(i) {
	var result = new ArrayBuffer(this.components[i].length);
	new Uint8Array(result).set(this.components[i]);
	return result;
	}

	/*
	* The "file name" in a name is the last component that isn't blank and doesn't start with one of the
	* special marker octets (for version, etc.). Return the index in this.components of
	* the file name, or -1 if not found.
	*/
	Name.prototype.indexOfFileName = function() {
	for (var i = this.components.length - 1; i >= 0; --i) {
	var component = this.components[i];
	if (component.length <= 0)
	continue;

	if (component[0] == 0 \|\| component[0] == 0xC0 \|\| component[0] == 0xC1 \|\|
	(component[0] >= 0xF5 && component[0] <= 0xFF))
	continue;

	return i;
	}

	return -1;
	}

	/*
	* Return true if this Name has the same components as name.
	*/
	Name.prototype.equalsName = function(name) {
	if (this.components.length != name.components.length)
	return false;

	// Start from the last component because they are more likely to differ.
	for (var i = this.components.length - 1; i >= 0; --i) {
	if (!DataUtils.arraysEqual(this.components[i], name.components[i]))
	return false;
	}

	return true;
	}

	/*
	* Find the last component in name that has a ContentDigest and return the digest value as Uint8Array,
	* or null if not found. See Name.getComponentContentDigestValue.
	*/
	Name.prototype.getContentDigestValue = function() {
	for (var i = this.components.length - 1; i >= 0; --i) {
	var digestValue = Name.getComponentContentDigestValue(this.components[i]);
	if (digestValue != null)
	return digestValue;
	}

	return null;
	}

	/*
	* If component is a ContentDigest, return the digest value as a Uint8Array subarray (don't modify!).
	* If not a ContentDigest, return null.
	* A ContentDigest component is Name.ContentDigestPrefix + 32 bytes + Name.ContentDigestSuffix.
	*/
	Name.getComponentContentDigestValue = function(component) {
	var digestComponentLength = Name.ContentDigestPrefix.length + 32 + Name.ContentDigestSuffix.length;
	// Check for the correct length and equal ContentDigestPrefix and ContentDigestSuffix.
	if (component.length == digestComponentLength &&
	DataUtils.arraysEqual(component.subarray(0, Name.ContentDigestPrefix.length),
	Name.ContentDigestPrefix) &&
	DataUtils.arraysEqual(component.subarray
	(component.length - Name.ContentDigestSuffix.length, component.length),
	Name.ContentDigestSuffix))
	return component.subarray(Name.ContentDigestPrefix.length, Name.ContentDigestPrefix.length + 32);
	else
	return null;
	}

	// Meta GUID "%C1.M.G%C1" + ContentDigest with a 32 byte BLOB.
	Name.ContentDigestPrefix = new Uint8Array([0xc1, 0x2e, 0x4d, 0x2e, 0x47, 0xc1, 0x01, 0xaa, 0x02, 0x85]);
	Name.ContentDigestSuffix = new Uint8Array([0x00]);

	/*
	* Return component as an escaped string according to "CCNx URI Scheme".
	* We can't use encodeURIComponent because that doesn't encode all the characters we want to.
	*/
	Name.toEscapedString = function(component) {
	var result = "";
	var gotNonDot = false;
	for (var i = 0; i < component.length; ++i) {
	if (component[i] != 0x2e) {
	gotNonDot = true;
	break;
	}
	}
	if (!gotNonDot) {
	// Special case for component of zero or more periods. Add 3 periods.
	result = "...";
	for (var i = 0; i < component.length; ++i)
	result += ".";
	}
	else {
	for (var i = 0; i < component.length; ++i) {
	var value = component[i];
	// Check for 0-9, A-Z, a-z, (+), (-), (.), (_)
	if (value >= 0x30 && value <= 0x39 \|\| value >= 0x41 && value <= 0x5a \|\|
	value >= 0x61 && value <= 0x7a \|\| value == 0x2b \|\| value == 0x2d \|\|
	value == 0x2e \|\| value == 0x5f)
	result += String.fromCharCode(value);
	else
	result += "%" + (value < 16 ? "0" : "") + value.toString(16).toUpperCase();
	}
	}
	return result;
	};

	/*
	* Return component as a Uint8Array by decoding the escapedString according to "CCNx URI Scheme".
	* If escapedString is "", "." or ".." then return null, which means to skip the component in the name.
	*/
	Name.fromEscapedString = function(escapedString) {
	var component = unescape(escapedString.trim());

	if (component.match(/[^.]/) == null) {
	// Special case for component of only periods.
	if (component.length <= 2)
	// Zero, one or two periods is illegal. Ignore this componenent to be
	// consistent with the C implementation.
	return null;
	else
	// Remove 3 periods.
	return DataUtils.toNumbersFromString(component.substr(3, component.length - 3));
	}
	else
	return DataUtils.toNumbersFromString(component);
	}

	Name.prototype.match = function(/Name/ name) {
	var i_name = this.components;
	var o_name = name.components;

	// The intrest name is longer than the name we are checking it against.
	if (i_name.length > o_name.length)
	return false;

	// Check if at least one of given components doesn't match.
	for (var i = 0; i < i_name.length; ++i) {
	if (!DataUtils.arraysEqual(i_name[i], o_name[i]))
	return false;
	}

	return true;
	};