node-xdelta3

node-xdelta3

Asynchronous, non-blocking Node.js binding for Xdelta3 binary diff utility

API

xdelta3.DiffStream(fd src, fd dst, [obj opt])

• src - original file
• dst - file to generate diff with
• opt - optional stream.Readable and xdelta3 configuration options
• iopt_size - default XD3_DEFAULT_IOPT_SIZE
• sprevsz - default XD3_DEFAULT_SPREVSZ
• smatch_cfg - default XD3_SMATCH_DEFAULT,
• winsize - default XD3_DEFAULT_WINSIZE,
• flags - default 0
• sec_data_ngroups - default 0
• sec_inst_ngroups - default 0
• sec_addr_ngroups - default 0

creates a readable stream

xdelta3.PatchStream(fd src, fd dest, [obj opt]);

• src - original file
• dest - file generated from diff
• opt - optional stream.Writable and xdelta3 configuration options

creates a writable stream

USAGE

var aDelta = new xdelta3.DiffStream(src, dst);
aDelta.on('data', function(bufferChunk) {
  console.log('chunk of diff received');
});
aDelta.on('end', function() {
  console.log('diff finished');
});
aDelta.on('error', function(err) {
  console.log('error: ' + err);
});

var aPatch = new xdelta3.PatchStream(src, dst);
for (var N = 0; N < aDiffBufferChunks.length; N++)
  aPatch.write(aDiffBufferChunks[i]);
aPatch.end();
aPatch.on('error', function(err) {
  console.log('error: ' + err);
});
aPatch.on('close', function() {
  console.log('patch finished');
});

DEPENDENCIES

This binding requires the existence of libxdelta3 in a shared library path:

• download the sources for a stable release - 3.0.6 here
• build the command line interface
• create the library from the existing objects:

gcc -shared xdelta3-xdelta3.o -o libxdelta3.so

• move the library to a shared lib path (ex /usr/local/lib)