EBUILD HOOKS

* It's a patching system that looks for existence of {pre,post}_${EBUILD_PHASE_FUNC}.ehook

and runs it to perform hook. It provides a way to patch packages we don't need to maintain.

It's loosly based on eapply_user function from /usr/lib/portage/python*/phase-helpers.sh script

and pre_src_prepare function from https://wiki.gentoo.org/wiki//etc/portage/patches link.

see /var/lib/layman/unity-gentoo/profiles/releases/profile.bashrc

* Overlay's ebuild hooks are located

in /var/lib/layman/unity-gentoo/profiles/ehooks directory.

* Optional ebuild hooks are managed via unity-extra/ehooks USE-flags

and ehook_use and ehook_require query functions (see below).

* Updates or changes are managed via /usr/bin/ehooks. It looks for ebuild

hooks changes and generates emerge command needed to apply the changes.

It's a symlink to /var/lib/layman/unity-gentoo/ehooks_check.sh script.

- usage:

ehooks [OPTION]

- options:

-c, --check generate emerge command when changes found

-r, --reset set changes as applied (reset modification time)

* Directory name and search order:

- e.g. package app-arch/file-roller-3.22.3-r0:0/0

1) app-arch/file-roller-3.22.3-r0:0

2) app-arch/file-roller-3.22.3-r0

3) app-arch/file-roller-3.22.3:0

4) app-arch/file-roller-3.22.3

5) app-arch/file-roller-3.22:0

6) app-arch/file-roller-3.22

7) app-arch/file-roller-3:0

8) app-arch/file-roller-3

9) app-arch/file-roller:0

10) app-arch/file-roller

- empty directory EXCLUDES package

* File format to trigger ebuild hook:

{pre,post}_${EBUILD_PHASE_FUNC}.ehook

1) pre_pkg_setup.ehook

2) post_pkg_setup.ehook

3) pre_src_unpack.ehook

4) post_src_unpack.ehook

5) pre_src_prepare.ehook

6) post_src_prepare.ehook

7) pre_src_configure.ehook

8) post_src_configure.ehook

9) pre_src_compile.ehook

10) post_src_compile.ehook

11) pre_src_install.ehook

12) post_src_install.ehook

13) pre_pkg_preinst.ehook

14) post_pkg_preinst.ehook

15) pre_pkg_postinst.ehook

16) post_pkg_postinst.ehook

- it's possible to use more files in one phase

see net-im/pidgin:

01-pre_pkg_setup.ehook

02-pre_pkg_setup.ehook

- it's possible to use filename prefix and sort it for better overview:

[...anything...]pre_src_prepare.ehook

01_pre_src_prepare.ehook

aa-pre_src_prepare.ehook

* File body:

ebuild_hook() {

[COMMANDS...]

}

- it's possible to use any ebuild functions

- templates are in .../ehooks/templates directory

the preferred way of using templates are symbolic links:

ln -s ../../templates/ubuntu-versionator_pkg_postinst.ehook 04-post_pkg_postinst.ehook

- command to apply patches in 'prepare' phase:

eapply "${EHOOK_FILESDIR}"

- command to trigger 'eautoreconf':

eautoreconf

and in post_src_prepare phase when 'eautoreconf' already used:

AT_NOELIBTOOLIZE="yes" eautoreconf

- errors log is located at ${T}/ehook.log

* ${EHOOK_FILESDIR}

- path to ${pkgdir}/files

- used for patches and miscellaneous files

- used for 'patches' directory from debian archive file

* Patch file format:

- extensions: *.patch or *.diff

- use filename prefix to control apply order

* Query functions:

ehook_use [USE-flag]

- it returns a true value if unity-extra/ehooks USE-flag is declared

- e.g. 'if ehook_use nemo_noroot; then'

see gnome-extra/nemo:

02-pre_src_prepare.ehook

ebuild_hook() {

if ehook_use nemo_noroot; then

sed -i \

-e "/gboolean show_open_as_root/{s/no_selection_or_one_dir/FALSE/}" \

src/nemo-view.c || die

einfo "'Open as Root' context menu action removed"

fi

}

ehook_require [USE-flag]

- it skips the rest of the related ebuild hooks if unity-extra/ehooks USE-flag is not declared

- it should be the first command of ebuild hooks

- e.g. 'ehook_require gnome-terminal_theme'

see x11-terms/gnome-terminal:

01-post_src_prepare.ehook

and x11-libs/vte:2.91:

01-post_src_prepare.ehook

* EHOOK_PATH variable defines the location of additional ebuild hooks. It provides a way

for users to apply their own ebuild hooks. It's set through /etc/portage/make.conf

- e.g. EHOOK_PATH="/home/ehooks"

- own directory OVERRIDES overlay's directory of the same name

- own empty directory DISABLES overlay's directory of the same name

- e.g. /home/ehooks/app-arch/file-roller

overrides or disables

/var/lib/layman/unity-gentoo/profiles/ehooks/app-arch/file-roller