Skycoin C library

Skycoin C library (a.k.a libskycoin) exports the Skycoin API to DApps using the C programming language. It is also the foundation to build client libraries for other programming languages.

Links

• skycoin.net
• Skycoin Blog
• Skycoin Docs
• Skycoin Blockchain Explorer
• Skycoin Development Telegram Channel
• Skycoin Github Wiki

Subprojects

The Skycoin C library is made of the following components

• lib/cgo : C wrappers for the Skycoin core API
• lib/swig : SWIG interfaces to generate wrappers around the Skycoin core API for other programming languages
• lib/swagger : Swagger specifications for generating REST API clients
• lib/curl : C REST client for the Skycoin HTTP API. Generated by openapi-generator. Powered by libcurl.

Consult respective README files for further details.

• Make rules
• Development setup
  • Running tests
  • Releases
    • Update the version
    • Pre-release testing
    • Creating release builds

Make Rules

All these make rules require skycoin to be a git submodule of libskycoin

Target	Help
build-libc-static	Build libskycoin C static library
build-libc-shared	Build libskycoin C shared library
build	Build all C libraries
build-libc	Build libskycoin C client libraries
build-skyapi	Build skyapi(libcurl based) library
test	Run all test for libskycoin
test-libc	Run tests for libskycoin C client library
test-skyapi	Run test for skyapi(libcurl based) library
docs	Generate documentation for all libraries
docs-libc	Generate libskycoin documentation
docs-skyapi	Generate SkyApi (libcurl) documentation
lint	Run linters. Use make install-linters first.
check	Run tests and linters
install-deps	Install deps for libc and skyapi
install-deps-libc	Install deps for libc
install-deps-skyapi	Install skyapi(libcurl based) library.
install-linters	Install linters
format	Formats the code. Must have goimports installed (use make install-linters).
clean	Clean all files generated by libraries(libcurl based and libc)
clean-libc	Clean files generated by libc
clean-skyapi	Clean files generated by skyapi

Development setup

Running tests

$ make test-libc

Releases

Update the version

0. If the master branch has commits that are not in develop (e.g. due to a hotfix applied to master), merge master into develop (and fix any build or test failures)
1. Switch to a new release branch named release-X.Y.Z for preparing the release.
2. If the release process needs modifications, edit these steps before moving forward
3. Ensure that the submodule at vendor/github.com/skycoin/skycoin is in sync with respect to the corresponding tag in https://github.com/skycoin/skycoin repository.
4. Update CHANGELOG.md: move the "unreleased" changes to the version and add the date.
5. Run make docs to regenerate documentation for all libraries and ensure they ar up-to-date.
6. Follow the steps in pre-release testing
7. Make a PR merging the release branch into master
8. Review the PR and merge it
9. Tag the master branch with the version number. Version tags start with v, e.g. v0.20.0. Sign the tag. If you have your GPG key in github, creating a release on the Github website will automatically tag the release. It can be tagged from the command line with git tag -as v0.20.0 $COMMIT_ID, but Github will not recognize it as a "release".
10. Release builds are created and uploaded by travis. To do it manually, checkout the master branch and make release.
11. Merge changes in master back into develop branch to start working towards next stable version.

Pre-release testing

Perform these actions before releasing:

make check

Release signing

Releases are signed with this PGP key:

0x5801631BD27C7874

The fingerprint for this key is:

pub   ed25519 2017-09-01 [SC] [expires: 2023-03-18]
      10A7 22B7 6F2F FE7B D238  0222 5801 631B D27C 7874
uid                      GZ-C SKYCOIN <token@protonmail.com>
sub   cv25519 2017-09-01 [E] [expires: 2023-03-18]

Keybase.io account: https://keybase.io/gzc

Alternative signing keys:

Keybase.io account: https://keybase.io/olemis

The fingerprint for this key is:

pub   rsa4096 2019-01-17 [SC] [expires: 2024-01-16]
uid           Olemis Lang <olemis@simelo.tech>
sub   rsa4096 2019-01-17 [E] [expires: 2024-01-16]

Follow the Tor Project's instructions for verifying signatures.

If you can't or don't want to import the keys from a keyserver, the signing key is available in the repo: gz-c.asc.

Releases and their signatures can be found on the releases page.

Instructions for generating a PGP key, publishing it, signing the tags and binaries: https://gist.github.com/gz-c/de3f9c43343b2f1a27c640fe529b067c

Development

We have two branches: master and develop.

• develop is the default branch and will always have the latest code. The submodule at gopath/src/github.com/skycoin/skycoin has to be in sync with skycoin/skycoin develop branch.
• master will always be equal to the current stable release on the website, and should correspond with the latest release tag. The submodule at gopath/src/github.com/skycoin/skycoin has to be in sync with skycoin/skycoin master branch.

Separate stable development branches will be created to work on releases for supporting the most recent stable version of Skycoin. The name of these branches should be the Skycoin major and minor version numbers followed by dev suffix e.g. 0.25dev. These branches may be forked out of either master or develop branches, and the submodule at gopath/src/github.com/skycoin/skycoin has to be in sync with the corresponding tag of skycoin/skycoin official repository.

Stable development branches are created most of the time for the following reasons:

• A Skycoin release increasing patch version number.
• Enhanced support and bug fixes for a version of the library compiled against an stable version of Skycoin
• Backporting useful features added in develop.

General development guidelines

The following rules are enforced

• Contributions must comply to the development guidelines documented in the Skycoin wiki.
• C / C++ code must comply to the Bitcoin C coding style (enforced by clang-format).

SkyApi libcurl client for Skycoin REST API

This wrapper is auto-generated by openapi-generator directly from Skycoin REST API code.

For further instructions see Autogenerated documentation.

Doxygen comment syntax

If you want to continue with the doxygen way(we recommend it) of coding and document functions, structs, and functions, you should follow the specifications found in the Doxygen official site.

An example of documentation using doxygen is the next:

/**
 * Addresses of Bitcoin accounts
 */
typedef struct {
    GoUint8_ Version;      ///< Address version identifier.
                           ///< Used to differentiate testnet
                           ///< vs mainnet addresses, for instance.
    cipher__Ripemd160 Key; ///< Address hash identifier.
} cipher__BitcoinAddress;

This code example can be found at include/cipher.bitcoin.go.h.

Inside /* */ we found struct documentation, meanwhile //< symbol is used to describe fields of the struct.

After that, run make docs for a new docs generation. You can found the api documentation at docs/libc folder.