RPM Build

RPM build steps:

  1. set up a directory hierarchy per the rpmbuild specifications
  2. place sources and supplemental files in the proper locations in the hierarchy
  3. create spec file
  4. build the RPM

step 1: build the hierarchy

Standard hierarchy contains five subdirectories:

  • SOURCES(%_sourcedir): contains source files
  • SPECS(%_specdir): contains spec files - one spece file per RPM you want to build
  • BUILD(%_builddir): space to compile the sources
  • BUILDROOT(%_buildrootdir): files are installed under here
  • RPMS(%_rpmdir): contains binary PRM that the rpmbuild builds
  • SRPMS(%_srcrpmdir): contains the source RPM built during the process

There at least need SOURCES and a spec file in SPECS.

step 2: copy the sources and files to SOURCES

Copy the sources, ideally bundled as a tarball, into the SOURCES directory. The name of sources tarball is package-version.tar.gz is better.

step 3: create spec file

A spec file is nothing more than a text file with a special syntax. But it is the key file for create rpm. All configuration, commands and informations about create, install and uninstall rpms are defined in this file.

The simplest way to build rpm is:

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> cd ~/rpmbuild/SPECS
> touch NAME.spec

rpmbuild will read Name.spec file and go throught in order the stages listed below:

  • %prep(%_sourcedir->%_builddir)
  • %build(%_builddir->%_builddir)
  • %check(%_builddir->%_builddir)
  • %install(%_builddir->%_buildrootdir)
  • bin(%_buildrootdir->%_rpmdir)
  • src(%_sourcedir->%_srcrpmdir)
%prep

This section describes how to unpack the compressed packages so that they can be built. Normally this section includes two macros:

  • %setup macro is used to unpack the original sources.
  • %patch macro is used to apply patches to the original source.
%build

This section describes how to configure and compile/build the files to be installed. Many programs use configure approach to config the sources, so:

  • %configure macro is used to automatically invoke the correct options.

and use make to compile files.

%install

This section creates directories and copy relavant files from %_builddir to %buildroot. Normally, some variation of make install is performed here.

%files

This section declares which files and directories are owned by the package, and thus which files and directories will be placed into binary RPM.

  • %defattr macro set the default file permissions, and is often found at the start of the%files section. Note that this is no longer necessary unless the permissions need to be altered.
Scriptlets

Scriptlets can be run:

  • before(%pre) or after(%post) a package is installed
  • before(%preun) or after(%postun) a package is uninstalled
  • at the start(%pretrans) or end(%posttrans) of a transcation

The order of operations during the upgrade is:

  1. Run the %pre of the RPM being installed
  2. Install the files that RPM provides
  3. Run the %post of RPM
  4. Run the %preun of the old package
  5. Delete any old files not overwritten by the newer version.
  6. Run the %postun of the old package

step4: build the RPM

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rpmbuild -ba NAME.spec

Reference