libsv

libsv - Public domain cross-platform semantic versioning in c99

Topics

• Introduction
• License
• Install
  • xmake
  • cmake
  • autotools
• Usage
• Credits
• Bugs, vulnerabilities and contributions
• Resources
• Badges and static analysis
  • Travis CI
  • Clang's Static Analyzer

Introduction

This is free and unencumbered software released into the public domain. This package installs a C language library implementing semantic versioning for the C language.

License

See the UNLICENSE file.

Install

xmake

Install xmake build system (A make-like build utility based on Lua)

$ xmake
$ xmake check
$ xmake install

cmake

$ mkdir build && cd build
$ cmake ..
$ make
$ make test
$ make install

autotools

To install from a proper release tarball, do this:

$ cd libsv-3.1
$ mkdir build
$ cd build
$ ../configure
$ make
$ make check
$ make install

to inspect the available configuration options:

$ ../configure --help

The Makefile is designed to allow parallel builds, so we can do:

$ make -j4 all && make -j4 check

which, on a 4-core CPU, should speed up building and checking significantly. The Makefile supports the DESTDIR environment variable to install files in a temporary location, example: to see what will happen:

$ make -n install DESTDIR=/tmp/libsv

to really do it:

$ make install DESTDIR=/tmp/libsv

After the installation it is possible to verify the installed library against the test suite with:

$ make installcheck

From a repository checkout or snapshot (the ones from the Github site): we must install the GNU Autotools (GNU Automake, GNU Autoconf, GNU Libtool), then we must first run the script "autogen.sh" from the top source directory, to generate the needed files:

$ cd libsv
$ sh autogen.sh

notice that "autogen.sh" will run the programs "autoreconf" and "libtoolize"; the latter is selected through the environment variable "LIBTOOLIZE", whose value can be customised; for example to run "glibtoolize" rather than "libtoolize" we do:

$ LIBTOOLIZE=glibtoolize sh autogen.sh

After this the procedure is the same as the one for building from a proper release tarball, but we have to enable maintainer mode:

$ ../configure --enable-maintainer-mode [options]
$ make
$ make check
$ make install

Usage

...
semver_t semver = {0};

semver(&semver, "v1.2.3-alpha.1");

assert(1 == semver.major);
assert(2 == semver.minor);
assert(3 == semver.patch);
assert(0 == memcmp("alpha", semver.prerelease.raw, sizeof("alpha")-1));
assert(0 == memcmp("1", semver.prerelease.next->raw, sizeof("1")-1));
assert(true == semver_rmatch(semver, "1.2.1 || >=1.2.3-alpha <1.2.5"));

semver_dtor(&semver);
...

Versions

A "version" is described by the v2.0.0 specification found at http://semver.org/.

A leading "v" character is stripped off and ignored.

Ranges

A version range is a set of comparators which specify versions that satisfy the range.

A comparator is composed of an operator and a version. The set of primitive operators is:

• < Less than
• <= Less than or equal to
• > Greater than
• >= Greater than or equal to
• = Equal. If no operator is specified, then equality is assumed, so this operator is optional, but MAY be included.

For example, the comparator >=1.2.7 would match the versions 1.2.7, 1.2.8, 2.5.3, and 1.3.9, but not the versions 1.2.6 or 1.1.0.

Comparators can be joined by whitespace to form a comparator set, which is satisfied by the intersection of all of the comparators it includes.

A range is composed of one or more comparator sets, joined by ||. A version matches a range if and only if every comparator in at least one of the ||-separated comparator sets is satisfied by the version.

For example, the range >=1.2.7 <1.3.0 would match the versions 1.2.7, 1.2.8, and 1.2.99, but not the versions 1.2.6, 1.3.0, or 1.1.0.

The range 1.2.7 || >=1.2.9 <2.0.0 would match the versions 1.2.7, 1.2.9, and 1.4.6, but not the versions 1.2.8 or 2.0.0.

Prerelease Tags

If a version has a prerelease tag (for example, 1.2.3-alpha.3) then it will only be allowed to satisfy comparator sets if at least one comparator with the same [major, minor, patch] tuple also has a prerelease tag.

For example, the range >1.2.3-alpha.3 would be allowed to match the version 1.2.3-alpha.7, but it would not be satisfied by 3.4.5-alpha.9, even though 3.4.5-alpha.9 is technically "greater than" 1.2.3-alpha.3 according to the SemVer sort rules. The version range only accepts prerelease tags on the 1.2.3 version. The version 3.4.5 would satisfy the range, because it does not have a prerelease flag, and 3.4.5 is greater than 1.2.3-alpha.7.

The purpose for this behavior is twofold. First, prerelease versions frequently are updated very quickly, and contain many breaking changes that are (by the author's design) not yet fit for public consumption. Therefore, by default, they are excluded from range matching semantics.

Second, a user who has opted into using a prerelease version has clearly indicated the intent to use that specific set of alpha/beta/rc versions. By including a prerelease tag in the range, the user is indicating that they are aware of the risk. However, it is still not appropriate to assume that they have opted into taking a similar risk on the next set of prerelease versions.

Advanced Range Syntax

Advanced range syntax desugars to primitive comparators in deterministic ways.

Advanced ranges may be combined in the same way as primitive comparators using white space or ||.

Hyphen Ranges X.Y.Z - A.B.C

Specifies an inclusive set.

• 1.2.3 - 2.3.4 := >=1.2.3 <=2.3.4

If a partial version is provided as the first version in the inclusive range, then the missing pieces are replaced with zeroes.

• 1.2 - 2.3.4 := >=1.2.0 <=2.3.4

If a partial version is provided as the second version in the inclusive range, then all versions that start with the supplied parts of the tuple are accepted, but nothing that would be greater than the provided tuple parts.

• 1.2.3 - 2.3 := >=1.2.3 <2.4.0
• 1.2.3 - 2 := >=1.2.3 <3.0.0

X-Ranges 1.2.x 1.X 1.2.* *

Any of X, x, or * may be used to "stand in" for one of the numeric values in the [major, minor, patch] tuple.

• * := >=0.0.0 (Any version satisfies)
• 1.x := >=1.0.0 <2.0.0 (Matching major version)
• 1.2.x := >=1.2.0 <1.3.0 (Matching major and minor versions)

A partial version range is treated as an X-Range, so the special character is in fact optional.

• "" (empty string) := * := >=0.0.0
• 1 := 1.x.x := >=1.0.0 <2.0.0
• 1.2 := 1.2.x := >=1.2.0 <1.3.0

Tilde Ranges ~1.2.3 ~1.2 ~1

Allows patch-level changes if a minor version is specified on the comparator. Allows minor-level changes if not.

• ~1.2.3 := >=1.2.3 <1.(2+1).0 := >=1.2.3 <1.3.0
• ~1.2 := >=1.2.0 <1.(2+1).0 := >=1.2.0 <1.3.0 (Same as 1.2.x)
• ~1 := >=1.0.0 <(1+1).0.0 := >=1.0.0 <2.0.0 (Same as 1.x)
• ~0.2.3 := >=0.2.3 <0.(2+1).0 := >=0.2.3 <0.3.0
• ~0.2 := >=0.2.0 <0.(2+1).0 := >=0.2.0 <0.3.0 (Same as 0.2.x)
• ~0 := >=0.0.0 <(0+1).0.0 := >=0.0.0 <1.0.0 (Same as 0.x)
• ~1.2.3-beta.2 := >=1.2.3-beta.2 <1.3.0 Note that prereleases in the 1.2.3 version will be allowed, if they are greater than or equal to beta.2. So, 1.2.3-beta.4 would be allowed, but 1.2.4-beta.2 would not, because it is a prerelease of a different [major, minor, patch] tuple.

Caret Ranges ^1.2.3 ^0.2.5 ^0.0.4

Allows changes that do not modify the left-most non-zero digit in the [major, minor, patch] tuple. In other words, this allows patch and minor updates for versions 1.0.0 and above, patch updates for versions 0.X >=0.1.0, and no updates for versions 0.0.X.

Many authors treat a 0.x version as if the x were the major "breaking-change" indicator.

Caret ranges are ideal when an author may make breaking changes between 0.2.4 and 0.3.0 releases, which is a common practice. However, it presumes that there will not be breaking changes between 0.2.4 and 0.2.5. It allows for changes that are presumed to be additive (but non-breaking), according to commonly observed practices.

• ^1.2.3 := >=1.2.3 <2.0.0
• ^0.2.3 := >=0.2.3 <0.3.0
• ^0.0.3 := >=0.0.3 <0.0.4
• ^1.2.3-beta.2 := >=1.2.3-beta.2 <2.0.0 Note that prereleases in the 1.2.3 version will be allowed, if they are greater than or equal to beta.2. So, 1.2.3-beta.4 would be allowed, but 1.2.4-beta.2 would not, because it is a prerelease of a different [major, minor, patch] tuple.
• ^0.0.3-beta := >=0.0.3-beta <0.0.4 Note that prereleases in the 0.0.3 version only will be allowed, if they are greater than or equal to beta. So, 0.0.3-pr.2 would be allowed.

When parsing caret ranges, a missing patch value desugars to the number 0, but will allow flexibility within that value, even if the major and minor versions are both 0.

• ^1.2.x := >=1.2.0 <2.0.0
• ^0.0.x := >=0.0.0 <0.1.0
• ^0.0 := >=0.0.0 <0.1.0

A missing minor and patch values will desugar to zero, but also allow flexibility within those values, even if the major version is zero.

• ^1.x := >=1.0.0 <2.0.0
• ^0.x := >=0.0.0 <1.0.0

Credits

The stuff was written by Lucas Abel https://github.com/uael and contributors

• Marco Maggi https://github.com/marcomaggi

Bugs, vulnerabilities and contributions

Bug and vulnerability reports are appreciated, all the vulnerability reports are public; register them using the Issue Tracker at the project's Github site. For contributions and patches please use the Pull Requests feature at the project's Github site.

Reports about the original code must be registered at: https://github.com/uael/sv/issues

Resources

Development of the original projects takes place at: https://github.com/uael/sv/

the GNU Project software can be found here: https://www.gnu.org/

Badges and static analysis

Travis CI

Travis CI is a hosted, distributed continuous integration service used to build and test software projects hosted at GitHub. We can find this project's dashboards at: https://travis-ci.org/uael/sv

Usage of this service is configured through the file ".travis.yml".

Clang's Static Analyzer

The Clang Static Analyzer is a source code analysis tool that finds bugs in C, C++, and Objective-C programs. It is distributed along with Clang and we can find it at: http://clang-analyzer.llvm.org/

Usage of this service is implemented with make rules; see the relevant section in the file "Makefile.am".