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diff --git a/docs/cpt.org b/docs/cpt.org new file mode 100644 index 0000000..bff8ac9 --- /dev/null +++ b/docs/cpt.org @@ -0,0 +1,940 @@ +#+TITLE: Carbs Packaging Tools +#+SUBTITLE: User Manual +#+AUTHOR: Cem Keylan +#+EMAIL: cem@ckyln.com +#+TEXINFO_FILENAME: cpt.info +#+TEXINFO_DIR_CATEGORY: Development +#+TEXINFO_DIR_TITLE: Carbs Packaging Tools: (cpt) +#+TEXINFO_DIR_DESC: Carbs Package Management Library +#+DATE: {{{modification-time(%B %d\, %Y, 1)}}} + +This is a reference document containing both the user-guide and the development +manual for *Carbs Packaging Tools*. For development logs see [[https://git.carbslinux.org/cpt][the git repository]]. + +* Table of Contents :TOC:noexport: +- [[#copying][Copying]] +- [[#preface][Preface]] +- [[#usage][Usage]] + - [[#cpt-alternatives][cpt-alternatives]] + - [[#cpt-build][cpt-build]] + - [[#cpt-checksum][cpt-checksum]] + - [[#cpt-download][cpt-download]] + - [[#cpt-install][cpt-install]] + - [[#cpt-list][cpt-list]] + - [[#cpt-remove][cpt-remove]] + - [[#cpt-search][cpt-search]] + - [[#cpt-update][cpt-update]] + - [[#global-flags][Global Flags]] +- [[#environment-variables][Environment Variables]] + - [[#cpt_path][=CPT_PATH=]] + - [[#cpt_compress][=CPT_COMPRESS=]] + - [[#cpt_force][=CPT_FORCE=]] + - [[#cpt_pid][=CPT_PID=]] +- [[#hooks][Hooks]] + - [[#editing-the-build-file-during-pre-build][Editing the =build= file during pre-build]] +- [[#packaging-system][Packaging System]] + - [[#build][=build=]] + - [[#sources][=sources=]] + - [[#checksums][=checksums=]] + - [[#version][=version=]] + - [[#depends][=depends=]] + - [[#post-install][=post-install=]] + - [[#message][=message=]] + - [[#test][=test=]] +- [[#rsync-repositories][Rsync Repositories]] + - [[#setting-up-an-rsync-repository][Setting up an Rsync repository]] +- [[#cpt-library][CPT Library]] + - [[#calling-the-library][Calling the library]] + - [[#option-parsing][Option parsing]] + - [[#message-functions][Message functions]] + - [[#text-functions][Text functions]] + - [[#system-functions][System Functions]] + +* Copying +:PROPERTIES: +:COPYING: t +:END: + +Copyright \copy 2020 Cem Keylan + +#+begin_quote +Permission is granted to copy, distribute and/or modify this document under the +terms of the GNU Free Documentation License, Version 1.3 or any later version +published by the Free Software Foundation; with no Invariant Sections, with no +Front-Cover Texts and no Back-Cover Texts. A copy of the license is included in +the section entitled "GNU Free Documentation License." +#+end_quote + +* Preface +:PROPERTIES: +:DESCRIPTION: Introduction to Carbs Packaging Tools +:END: + +Carbs Linux uses its own package management toolchain named =cpt= which was +initially forked from the [[https://github.com/kisslinux/kiss][kiss]] package manager. Unlike =kiss=, however, its main +goal is being easily extendable. Instead of being a single file package manager, +it revolves around the shell library =cpt-lib=, and many tools that wrap around +it. This document aims to document both the usage of the distributed tools and +document the library functions. + +* Usage +:PROPERTIES: +:DESCRIPTION: Basic usage of Carbs Packaging Tools +:END: + +=cpt= is formed of many tools combined in a single environment, similar to +=git=. When you run =cpt= without any arguments, it will show all available +tools and their explanations. Here is an example call with extra scripts on my +system: + +#+BEGIN_EXAMPLE + -> Carbs Packaging Tool + -> add Commit the current directory as a new package + -> alternatives List and swap to alternatives + -> build Build a package + -> bump Commit the current directory as a version bump + -> cargo-urlgen Create static cargo sources for Rust packages + -> cargolock-urlgen Convert the given Cargo.lock file to sources + -> cat Concatanate package files in the installed package database + -> changelog Print the git log of the specific package + -> chbuild Create/destroy temporary chroots + -> checkmissing Verify package manifests + -> checksum Generate checksums + -> chroot Enter a chroot + -> commit Commit a package without the prefix of 'package:' + -> depends Display a package's dependencies + -> download Download sources for the given package + -> exec Execute a command inside the alternatives system + -> export Turn an installed package into a CPT tarball + -> fork Fork a package to the current directory + -> getchoice Prints the full path to a file in the alternatives system. + -> install Install a package + -> link Link a forked package's files to the other repository + -> list List installed packages + -> maintainer Find the maintainer of a package + -> manifest Display all files owned by a package + -> manifest-tree Display all files owned by a package with a tree view + -> new Create a boilerplate CPT package + -> orphans List orphaned packages + -> owns Check which package owns a file + -> rel Bump the release number of a package + -> remove Remove a package + -> repodepends Display a package's dependencies in the repository + -> reporevdepends Display packages on the repository which depend on package + -> reset Remove all packages except for the base + -> revdepends Display packages which depend on package + -> search Search for a package + -> size Show the size on disk for a package + -> source Extract sources of a given package to the current directory + -> update Check for updates +#+END_EXAMPLE + +** cpt-alternatives +:PROPERTIES: +:DESCRIPTION: List and swap to alternatives +:END: + +You can list and swap to alternatives using =cpt-alternatives=, or +=cpt a= for short. When run without alternatives, it will list +alternatives. It can read from standard input if =-= is given as an +argument. + +*Examples* + +1. List alternatives. + +#+BEGIN_EXAMPLE + $ cpt-alternatives + ncurses /usr/bin/clear + ncurses /usr/bin/reset +#+END_EXAMPLE + +2. Swap to =clear= from =ncurses=. + +#+BEGIN_EXAMPLE + $ cpt-alternatives ncurses /usr/bin/clear + -> Swapping '/usr/bin/clear' from 'busybox' to 'ncurses' +#+END_EXAMPLE + +3. Swap in bulk (all of =sbase=). + +#+BEGIN_EXAMPLE + $ cpt a | grep ^sbase | cpt a - +#+END_EXAMPLE + +** cpt-build +:PROPERTIES: +:DESCRIPTION: Build a package +:END: + +=cpt-build= will build given packages and their dependencies. If multiple +packages are specified, it will ask to install the packages as well. + +| Flags | Explanation | +|----------------+--------------| +| =-t=, =--test= | Run tests | + +** cpt-checksum +:PROPERTIES: +:DESCRIPTION: Generate checksums +:END: + +=cpt-checksum= will generate a =checksums= file from the package's sources. + +** cpt-download +:PROPERTIES: +:DESCRIPTION: Download sources for the given package +:END: + +=cpt-download= will download the sources of a package. + +** cpt-install +:PROPERTIES: +:DESCRIPTION: Install a package +:END: + +=cpt-install= will install given packages. + +** cpt-list +:PROPERTIES: +:DESCRIPTION: List installed packages +:END: + +When called without arguments, =cpt-list= will print all installed +packages. You can add package names as arguments to check whether they are +installed or not. In success, =cpt-list= will exit with status 0 if all +given packages are installed, it will return 1 if any of the given packages +aren't installed. + +| Flags | Explanation | +|-------------------+----------------------------------------| +| =-c=, =--current= | Use the current directory as a package | + +** cpt-remove +:PROPERTIES: +:DESCRIPTION: Remove a package +:END: + +=cpt-remove= will remove given packages. + +** cpt-search +:PROPERTIES: +:DESCRIPTION: Search for a package +:END: + +=cpt-search= will search for packages, it accepts regular expressions as well. + +| Flags | Explanation | +|------------------+-------------------------------------------| +| =-s=, =--single= | Only show the first instance of a package | + + +#+BEGIN_EXAMPLE + $ cpt-search 'alsa-*' + /var/db/cpt/repo/extra/alsa-lib + /var/db/cpt/repo/extra/alsa-utils + /var/db/cpt/installed/alsa-lib + /var/db/cpt/installed/alsa-utils + + $ cpt-search emacs + /home/cem/repos/main/community/emacs + /home/cem/repos/kiss-community/community/emacs + /var/db/cpt/installed/emacs + + $ cpt-search --single emacs + /home/cem/repos/main/community/emacs +#+END_EXAMPLE + +** cpt-update +:PROPERTIES: +:DESCRIPTION: Check for updates +:END: + +=cpt-update= will update the packages on your system. It fetches remote +repositories, and builds, and installs packages that have versions different +from the ones installed on the system. It doesn't check if the version string +is actually higher, it only checks whether they differ. + +| Flags | Explanation | +|----------------------+--------------------------------------| +| =-d=, =--download= | Only download updatable packages | +| =-n=, =--no-fetch= | Do not update remote repositories | +| =-o=, =--only-fetch= | Only fetch the repositories and exit | + +** Global Flags +:PROPERTIES: +:DESCRIPTION: Flags that work globally on some cpt utilities +:END: + +| Flags | Explanation | +|---------------------+----------------------------------| +| =-f=, =--force= | Force operation, [[=CPT_FORCE=][See =CPT_FORCE=]] | +| =-y=, =--no-prompt= | Do not prompt for confirmation | +| =-root CPT_ROOT= | Use an alternate root directory | +| =-h=, =--help= | Show this help message | +| =-v=, =--version= | Print version information | + +* Environment Variables +:PROPERTIES: +:DESCRIPTION: Change the behaviour of cpt through environment configuration +:END: + +Since there is no configuration file for cpt, the package manager is configured +through environment variables. These can be set per operation, or be set to your +shell configuration or =~/.profile=. Here are the environment variables that +alter the behaviour of =cpt=: + +| ENVIRONMENT VARIABLE | Effects | +|----------------------+-------------------------------------------------------------------------------| +| =CPT_PATH= | Set the locations of your repositories. It is similar to the =PATH= variable. | +| =XDG_CACHE_HOME= | Unless this is set, the =~/.cache= directory will be used instead. | +| =CPT_CACHE= | The cache directory for =cpt=. Default: =$XDG_CACHE_HOME/cpt= | +| =CPT_CHOICE= | If this is set to 0, a package installation will be aborted on conflicts. | +| =CPT_COMPRESS= | Program used to compress package tarballs. | +| =CPT_DEBUG= | If set to 1, temporary directories will not be removed after the operation. | +| =CPT_FETCH= | If set to 0, =cpt-update= will not fetch repositories. | +| =CPT_FORCE= | Force operation. | +| =CPT_HOOK= | Location for the hook file. | +| =CPT_KEEPLOG= | If set to 1, cpt will keep logs regardless of operation success. | +| =CPT_PID= | Set the temporary build directory name. | +| =CPT_PROMPT= | If set to 0, =cpt= will not prompt you for anything. | +| =CPT_ROOT= | If this variable is set, =cpt= will assume this as the system root. | +| =CPT_TEST= | If set to 1, =cpt-build= will run tests whenever available. | +| =CPT_TMPDIR= | The directory to create the temporary directories. | + +** =CPT_PATH= +:PROPERTIES: +:DESCRIPTION: Set the locations of your repositories +:END: + +Similar to the =PATH= variable, =cpt= find repositories from the =CPT_PATH= +variable. Here is an example: + +#+begin_src sh + CPT_PATH=$HOME/repos/repo1:$HOME/repos/repo2:$HOME/repos/repo3 +#+end_src + +This is a simplistic and a structured example for repository locations, but it +doesn't necessarily need to be as tidy as the example above. Here is an example +for something a little more complex. + +#+begin_src sh + CPT_PATH=$HOME/repos/overrides:/var/db/cpt/repo/core:/var/db/cpt/repo/extra:$HOME/repos/personal +#+end_src + +This example brings us to the next section of this document. + +*** Repository preferences +:PROPERTIES: +:DESCRIPTION: Prioritise package repositories +:END: + +When you are using multiple repositories from multiple vendors, you will find +out that some repositories have the same packages. =cpt= doesn't care about +conflicting packages. If you want to build a package that exists on multiple +repositories, =cpt= will build the first matching package. This means that if +=grep= package (for the sake of an example) exists on both +=$HOME/repos/personal= and =$HOME/repos/carbs/extra=, and you want +to install from your personal repository, you must set =CPT_PATH= so that your +personal repository is listed before the =extra= repository. + +#+begin_src sh + CPT_PATH=$HOME/repos/personal:$HOME/repos/carbs/extra +#+end_src + +*** Setting the =CPT_PATH= +:PROPERTIES: +:DESCRIPTION: Set the value of CPT_PATH on your shell configuration +:END: + +You can set the =CPT_PATH= variable on your shell configuration or your +=.profile= file in a way that is easy to read. + +The below example sets =CPT_PATH= in a way that is easy to understand which +repository comes first: + +#+begin_src sh + CPT_PATH=$HOME/repos/overrides + CPT_PATH=$CPT_PATH:$HOME/repos/carbs/core + CPT_PATH=$CPT_PATH:$HOME/repos/carbs/extra + CPT_PATH=$CPT_PATH:$HOME/repos/carbs/xorg + CPT_PATH=$CPT_PATH:$HOME/repos/personal + export CPT_PATH +#+end_src + +** =CPT_COMPRESS= +:PROPERTIES: +:DESCRIPTION: Compression tool to use in cpt +:END: + +When setting the =CPT_COMPRESS= value, you should set the name of the default +suffixes for the program. Available values are: + +- =gz= +- =zst= +- =bz2= +- =xz= + +Defaults to =gz=. + +** =CPT_FORCE= +:PROPERTIES: +:DESCRIPTION: Force operations on cpt +:END: + +If this is set to 1, some of the =cpt= tools will continue regardless of +errors or skip certain checks. Here are some examples: + +- =cpt-install= will install a package without verifying its manifest. +- =cpt-install= will install a package even when there are missing dependencies. +- =cpt-remove= will remove packages even when there are other packages that + depend on the current package. + +Defaults to 0. + +** =CPT_PID= +:PROPERTIES: +:DESCRIPTION: Set reproducible temporary directories +:END: + +If this variable is set, the temporary files will be created with this variable +as the suffix, instead of the PID of the =cpt= process. The advantage is that +you can know exactly where the build directory is located, while the +disadvantage is that there will be issues with multiple operations at the same +time. So the best way to use this variable is during one-time =cpt= calls. + +#+BEGIN_EXAMPLE + CPT_PID=mesa cpt b mesa +#+END_EXAMPLE + +By running the above, you will know that the created build directories will end +with the =*-mesa= suffix. + +* Hooks +:PROPERTIES: +:DESCRIPTION: Use hooks to customize the package manager operations +:END: + +Hooks can be used in order to change the runtime behaviour of the package manager. +There are a variety of package hooks, mostly self explanatory: + +- pre-build +- post-build +- build-fail +- pre-test +- test-fail +- pre-install +- post-install +- pre-remove +- post-remove +- pre-fetch +- post-fetch +- post-package + +In order to use hooks, you will need to set the =CPT_HOOK= variable pointing to +your hook file. Your hook file *MUST* be a POSIX shell script as its contents +are sourced by the package manager. + +The hook is given 3 variables when it is executed. Those are: + +| Variable | Explanation | +|----------+--------------------------------------------------------------| +| =$TYPE= | The type of the hook, (=pre-build=, =post-build=, etc.) | +| =$PKG= | The package that =cpt= is currently working on. Can be null. | +| =$DEST= | The destination of the operation. Can be null. | + +** Editing the =build= file during pre-build +:PROPERTIES: +:DESCRIPTION: Modify a package build with your hooks +:END: + +You can edit the =build= file during pre-build. The file is copied from the +repository to the build directory named as =.build.cpt=. You can use =sed= or +any other tool to edit the build file. After the build is complete, a =diff= +file will be placed to the package database named as =build.diff=. Here is an +example =build= file manipulation during the pre-build hook. + +#+BEGIN_SRC sh + cat <<EOF> .build.cpt + #!/bin/sh -e + + for patch in bash50-0??; do + patch -p0 < "\$patch" + done + + export LDFLAGS=-static + + ./configure \ + --prefix=/usr \ + --without-bash-malloc \ + --disable-nls + + export MAKEFLAGS="TERMCAP_LIB=/usr/lib/libncursesw.a $MAKEFLAGS" + + make + make DESTDIR="\$1" install + + ln -s bash "\$1/usr/bin/sh" + EOF +#+END_SRC + +* Packaging System +:PROPERTIES: +:DESCRIPTION: More detail on creating packages +:END: + +A package is formed of several files, these are: + +- [[=build=]] +- [[=sources=]] +- [[=checksums=]] +- [[=version=]] +- [[=depends=]] +- [[=post-install=]] +- [[=message=]] +- [[=test=]] + +Any other file can be added to the package directory at the discretion of the +package maintainer. Everything in the package directory will also be added to the +package database that is located on =/var/db/cpt/installed=. These can be +patches, configuration files, etc. + +** =build= +:PROPERTIES: +:DESCRIPTION: The build script +:END: + +Typically =build= files are shell scripts that run commands to prepare the source +code to be installed on the target system. Even though we will be assuming that +the =build= file is a POSIX shell script (for portability's sake), =build= +files can be any executable program from binary programs to =perl= scripts. + +The contents of a build script do not need to follow a certain rule for the +package manager, except for the fact that the user needs the permission to +execute the file. + +An important advice is to append an '-e' to the shebang (#!/bin/sh -e) so that +the build script exits on compilation error. + +Build is run with three arguments (=$#=) + +- Location of the package directory (DESTDIR) +- Package version +- System architecture + +** =sources= +:PROPERTIES: +:DESCRIPTION: The file containing package sources +:END: + +=sources= file is a list of files and sources that will be put to the build +directory during the build process. Those can be remote sources (such as tarballs), +git repositories, and files that reside on the package directory. + +The syntax is pretty simple for the =soures= file; =src dest=. The =dest= +parameter is optional. It is the directory that the source will be placed in. +Here is the =sources= file for the =gst-plugins= package: + +#+BEGIN_EXAMPLE + https://gstreamer.freedesktop.org/src/gst-plugins-good/gst-plugins-good-1.16.2.tar.xz good + https://gstreamer.freedesktop.org/src/gst-plugins-bad/gst-plugins-bad-1.16.2.tar.xz bad + https://gstreamer.freedesktop.org/src/gst-plugins-ugly/gst-plugins-ugly-1.16.2.tar.xz ugly + https://gstreamer.freedesktop.org/src/gst-libav/gst-libav-1.16.2.tar.xz libav +#+END_EXAMPLE + +This file is read from the package manager as space seperated. Files that begin +with a =#= comment are ignored. The first value points to the location of the +source. + +If it starts with a protcol url, (such as ftp:// http:// https://) it will be +downloaded with =curl=. + +If the source is a git repository, it shall be prefixed with a =git+= git(1) will +be used to do a shallow clone of the repository. If the commit is suffixed by a +history pointer, git will checkout the relevant revision. So, + +- =git+git://example.com/pub/repo@v1.2.3= :: will checkout the tag named "v1.2.3" +- =git+git://example.com/pub/repo#development= :: will checkout the branch named "development" +- =git+git://example.com/pub/repo#1a314s87= :: will checkout the commit named "1a314s87" + +Other files are assumed to be residing in the package directory. They should be +added with their paths relative to the package directory. + +** =checksums= +:PROPERTIES: +:DESCRIPTION: The file containing sha256sum of the sources +:END: + +checksums file is generated by the =cpt c pkg= command. It is generated +according to the order of the sources file. That's why you shouldn't be editing +it manually. The checksums file is created with the digests of the files using +the sha256 algorithm. + +** =version= +:PROPERTIES: +:DESCRIPTION: The file containing the version and the release numbers of a package +:END: + +The version file includes the version of the software and the release number of +of the package on a space seperated format. The contents of the file should look +like below. + +#+BEGIN_EXAMPLE + 1.3.2 1 +#+END_EXAMPLE + +** =depends= +:PROPERTIES: +:DESCRIPTION: The file containing the dependencies of a package +:END: + +This is a list of dependencies that must be installed before a package build. You +can append "make" after a dependency to mark a package is only required during +the build process of a package. Packages marked as a make dependency can be +removed after the build. There are also "test" dependencies. These dependencies +are only installed if either the =CPT_TEST= is set to 1, or the build is run +with the =-t= or =--test= options. So, a package package could have +the following =depends= file: + +#+BEGIN_EXAMPLE + linux-headers make + python test + zlib +#+END_EXAMPLE + +** =post-install= +:PROPERTIES: +:DESCRIPTION: The post-installation script +:END: + +=post-install= files have the same requirements as the build script. They +will be run after the package is installed as root (or as the user if the user +has write permissions on =CPT_ROOT=). + +** =message= +:PROPERTIES: +:DESCRIPTION: The post-installation message to be displayed +:END: + +This plaintext file will be outputted with =cat= after every package is +installed. + +** =test= +:PROPERTIES: +:DESCRIPTION: The test script for a package +:END: + +Test files are mainly for the repository maintainer to test the packages, and +will only run if the user has the =CPT_TEST= variable set, or the build is +run with the =-t= or =--test= options. This script is run on the +build directory. It is run right after the build script is finished. + +* Rsync Repositories +:PROPERTIES: +:DESCRIPTION: Information on using or creating rsync repositories +:END: + +Rsync repositories are simple to serve and simple to use. In the repository +directory, there needs to be a =.rsync= file that points to the remote of the +repository. This is used in order to fetch changes from the upstream. =.rsync= +file looks like this for the core repository: + +#+BEGIN_EXAMPLE + rsync://carbslinux.org/repo/core +#+END_EXAMPLE + +Rsync repositories have some few distinctions when it comes to fetching them. +They can be either synced individually or as a "root". There are 2 important +files, those are =.rsync= and =.rsync_root=. Here is the Carbs Linux +rsync repository structure. + +#+BEGIN_EXAMPLE + / + ----------------- + | | + .rsync core/ + ---------------- + | | + .rsync .rsync_root +#+END_EXAMPLE + +Unlike git repositories, they don't have a defined "root" directory. This is +both an advantage and a disadvantage. This way, we can sync individual +repositories, but that also means we need extra files to define root directories +and repository locations. Here is the content for each of these files: + +#+BEGIN_EXAMPLE + /.rsync: rsync://carbslinux.org/repo + /core/.rsync: rsync://carbslinux.org/repo/core + /core/.rsync_root: .. +#+END_EXAMPLE + +The =.rsync_root= file on the core repository points to the upper directory. +If a =.rsync= file exists on the upper directory, this means that is the whole +repository and will sync the entire repository instead of each individual repository. + +If the upper directory doesn't have this =.rsync= file, this means that this +is an individual repository, and the package manager will fetch accordingly. + +** Setting up an Rsync repository +:PROPERTIES: +:DESCRIPTION: Set up a repository for distribution +:END: + +Carbs Linux repositories automatically sync from the git repostitories and serve +it through the rsync daemon. Here is a sample shell script that I use in order to +sync repositories. Feel free to customize for your own use. + +#+BEGIN_SRC sh + #!/bin/sh + HOSTNAME="rsync://carbslinux.org/repo" + GITDIR="/pub/git/repo" + SHAREDIR="/pub/share/repo" + git -C "$GITDIR" pull + + rsync -avcC --delete --include=core --exclude=.rsync,.rsync_root "$GITDIR/." "$SHAREDIR" + + printf '%s\n' "$HOSTNAME" > "$GITDIR/.rsync" + for dir in "$GITDIR/"*; do + [ -d "$dir" ] || continue + [ -f "$dir/.rsync" ] || + printf '%s/%s\n' "$HOSTNAME" "${dir##*/}" > "$dir/.rsync" + printf '..\n' > "$dir/.rsync_root" + done +#+END_SRC + +You can then create an *rsync* user for serving the repositories. + +#+BEGIN_EXAMPLE + $ adduser -SD rsync +#+END_EXAMPLE + +Create =/etc/rsyncd.conf= and a service configuration as well. + +#+BEGIN_EXAMPLE + uid = rsync + gid = rsync + address = example.com + max connections = 10 + use chroot = yes + + [repo] + path = /pub/share/repo + comment = My repository +#+END_EXAMPLE + +Create a service file at =/etc/sv/rsync/run= (runit): + +#+BEGIN_SRC sh + #!/bin/sh -e + exec rsync --daemon --no-detach +#+END_SRC + +* CPT Library +:PROPERTIES: +:DESCRIPTION: Documentation of the Library +:END: + +=cpt-lib= is the library of Carbs Packaging Tools which can be used to extend +the functionality of the package manager. This is the API documentation of the +package manager library. + +** Calling the library +:PROPERTIES: +:DESCRIPTION: Including the library on your code +:END: + +You can call the library on your scripts by adding the following line to your +files: + +#+begin_src sh + #!/bin/sh -e + . cpt-lib +#+end_src + +This will load the library inside your script, and will set some environment +variables that are used inside the package manager. + +** Option parsing +:PROPERTIES: +:DESCRIPTION: Easy way of parsing options with cpt-lib +:END: + +=cpt-lib= includes a POSIX-shell option parser inside named =getoptions=. You +can see its own [[https://github.com/ko1nksm/getoptions/blob/v2.0.1/README.md][documentation]] for writing an option parser. The built-in version +of the =getoptions= library is 2.0.1 and there are no plans for updating it +apart from bug fixes. + +*** Defining a parser +:PROPERTIES: +:DESCRIPTION: Correct way of using getoptions +:END: + +Some functions are called and set automatically when you call =cpt-lib=, so you +shouldn't define the option parser after calling the library, as some of the +variables will already be set. + +If the function =parser_definition()= as defined when =cpt-lib= is called, +cpt-lib will handle the option parsing itself by calling =getoptions= +inside. Here is the proper way of doing it. + +#+begin_src sh + #!/bin/sh -e + + parser_definition() { + # The rest arguments MUST be defined as 'REST' + setup REST help:usage -- "usage: ${0##*/} [options] [pkg...]" + msg -- '' 'Options:' + flag CPT_TEST -t export:1 init:@export -- "Enable tests" + + global_options + } + + . cpt-lib +#+end_src + +*** =global_options()= +:PROPERTIES: +:DESCRIPTION: Convenience function for defining common flags +:END: + +The =global_options()= function is a simple convenience call to include flags +that can be used inside most =cpt= tools. It defines the following flags: + +| Flag | Long Option | Calls | +|------+-------------+--------------| +| -f | --force | =CPT_FORCE= | +| -y | --no-prompt | =CPT_PROMPT= | +| | --root | =CPT_ROOT= | +| -h | --help | =usage()= | +| -v | --version | =version()= | + +** Message functions +:PROPERTIES: +:DESCRIPTION: Communicate to users +:END: +=cpt= has various functions to print information to users. +*** =out()= +:PROPERTIES: +:DESCRIPTION: Print a message as-is +:END: + +=out()= is a really simple function that prints messages to the standard +output. It prints every argument with a newline. It is not meant to communicate +with the user, it just exists to have a simple function to interact with other +functions. + +#+begin_src sh + $ out "This is an example call" "How are you?" + This is an example call + How are you? +#+end_src + +*** =log()= +:PROPERTIES: +:DESCRIPTION: Print a message prettily +:END: + +=log()= is the most commonly used message function in the package manager. It is +used to pretty print messages with visual cues, so it is easier to read and +understand for the users. It changes message output for each argument it +receives (takes up to three arguments). + +- If it takes a single argument, it prints a yellow leading arrow followed by + colorless text. +- If it takes two arguments, it prints a yellow leading arrow followed by the + first argument (colored blue), and then followed by colorless second argument. +- If it takes three arguments, instead of a yellow arrow, it prints the third + argument in yellow, followed by the same two arguments as above. + +*** =die()= +:PROPERTIES: +:DESCRIPTION: Print a message and exit with error +:END: + +=die()= wraps the =log()= function and exits with an error (1). It takes one or +two arguments, which are sent to the =log()= function. The third argument for +=log()= is set as =!>=. + +*** =warn()= +:PROPERTIES: +:DESCRIPTION: Print a warning message +:END: + +=warn()= is another function that wraps =log()=. In place of the third argument, +it uses the word =WARNING=. + +*** =prompt()= +:PROPERTIES: +:DESCRIPTION: Ask the user whether they want to continue +:END: + +=prompt()= is an interactive function that waits for user input to continue. +It takes a single argument string to print a message, and then asks the user +whether they want to continue or not. Prompts can be disabled by the user if +they use a flag to disable them or set =CPT_PROMPT= to 0. + +** Text functions +:PROPERTIES: +:DESCRIPTION: Manipulate or check text +:END: + +Following functions are used to manipulate, check, or interact with text. + +*** =contains()= +:PROPERTIES: +:DESCRIPTION: Check if a "string list" contains a word +:END: + +=contains= function can be used to check whether a list variable contains a +given string. If the string is inside the list, it will return 0, otherwise 1. + +#+begin_src sh + # Usage + contains "$LIST" foo + + contains "foo bar" foo # Returns 0 + contains "foo bar" baz # Returns 1 +#+end_src + +*** =regesc()= +:PROPERTIES: +:DESCRIPTION: Escape regular expression characters +:END: + +=regesc()= can be used to escape regular expression characters that are defined +in POSIX BRE. Those characters are, =$=, =.=, =*=, =[=, =\\=, and =^=. + +#+begin_src sh + regesc '^[$\' # Returns \^\[\$\\ +#+end_src + +*** =pop()= +:PROPERTIES: +:DESCRIPTION: Remove an item from a string list +:END: + +=pop()= can be used to remove a word from a "string list" without a =sed= +call. Word splitting is intentional when using this function. + +#+begin_src sh + # Usage + pop foo from $LIST + + pop foo from foo baz bar # Returns baz bar +#+end_src + +** System Functions +*** =as_root()= +:PROPERTIES: +:DESCRIPTION: Run a command as the root user +:END: + +=as_root()= calls the rest of the arguments as a different user. Unless a =user= +environment variable is set, it will call the following arguments as the root +user. It supports the following programs for privilege escalation with the +following order: + +1. =sudo= +2. =doas= +3. =su= |