HPSM

This project defines the functionality to do High Precision Snippet Matching on any file. The main principle is based on semi brute force search.

• Each line of the file is normalized and then hashed using CRC8.
• The file with the given MD5 is also hashed.
• The longest sequence of CRCs is calculated doing greedy advance on local and remote file.

The functionality is available by:

• API: an endpoint receives a json structure defining a set of <[hashes]> to be processed. The API could be deployed on the sources server or can download the sources from several servers.
• libhpsm: A shared library that provides local processing (by downloading from ossk.org) or remote processing (calling the above mentioned API). It also provides functionallity to hash the content of a file. ("hpsm=01234586787887....")
• CLI: A simple shell console can be used to:
  • Get the hpsm= string to be appended to wfp file
  • Get the .wfp file containing the hpsm= string
  • Compare two files in a graphical view. The first file must be local but the second file can be local or a remote MD5
• go module A go package (Coming soon).

Remote Files

By default, files from localhost/api/file_contents are retrieved. If other sources server is used, the environment variable SCANOSS_FILE_CONTENTS_URL must be used. Eg:

export SCANOSS_FILE_CONTENTS_URL=https://api.scanoss.com/file_contents/

You can also set the environmental variable SCANOSS_API_KEY that will be passed as the X-Session header.

export SCANOSS_API_KEY=[YOUR_KEY]

Building

A makefile is provided to automate the building process

make build_lib

Creates libhpsm.so and libhpsm.h. libhpsm.so must be placed on /usr/lib to make the feature available. libhpsm.h should be used by the client application, eg: inc/ folder

make build_cli

Creates hpsm cli application

make build_amd

Builds and packages hpsm lib and cli application. Creates temporary directory scripts with hpsm (binary), libhpsm.so (lib), and libhpsm.h (header file).

make install

Copy both files libhpsm.so and hpsm to their destination to make the feature work (/usr/lib and /usr/bin/)

make clean

Removes compiled binaries libhpsm.so and hpsm

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