[Buildroot] [PATCH v2 0/2] improve virtual package management

[Buildroot] [PATCH v2 0/2] improve virtual package management

[Eric Le Bihan]

This patch series improves virtual package management by:

- using make control functions in dependency check.
- adding a tutorial to the user manual.

Changes v1 -> v2:
  - rebased on master.
  - replaced 'infrastructure' by 'management' as this mechanism does not (yet?)
    provide a "$(eval $(virtual-package))" helper
  - converted code examples to plain sections (suggested by Yann E. Morin).

Best regards,
ELB

Eric Le Bihan (2):
  packages: improve dependency check in virtual packages.
  manual: add virtual package tutorial.

 docs/manual/adding-packages-virtual.txt  |   99 ++++++++++++++++++++++++++++++
 docs/manual/adding-packages.txt          |    2 +
 package/luainterpreter/luainterpreter.mk |    6 ++
 package/opengl/libegl/libegl.mk          |    7 +--
 package/opengl/libgles/libgles.mk        |    7 +--
 package/opengl/libopenmax/libopenmax.mk  |    7 +--
 package/opengl/libopenvg/libopenvg.mk    |    7 +--
 package/powervr/powervr.mk               |    7 +--
 8 files changed, 122 insertions(+), 20 deletions(-)
 create mode 100644 docs/manual/adding-packages-virtual.txt

-- 
1.7.9.5

[Buildroot] [PATCH v2 1/2] packages: improve dependency check in virtual packages.

[Eric Le Bihan]

The current version of dependency check for virtual package <foo>
defines FOO_CONFIGURE_CMDS to print an error message if the
dependencies are not met.

This patch updates all the virtual packages to use the GNU Make control
function $(error text...) instead.

This makes the error happen at the beginning of the build, with a clearer
message.

Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
---
 package/luainterpreter/luainterpreter.mk |    6 ++++++
 package/opengl/libegl/libegl.mk          |    7 +++----
 package/opengl/libgles/libgles.mk        |    7 +++----
 package/opengl/libopenmax/libopenmax.mk  |    7 +++----
 package/opengl/libopenvg/libopenvg.mk    |    7 +++----
 package/powervr/powervr.mk               |    7 +++----
 6 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/package/luainterpreter/luainterpreter.mk b/package/luainterpreter/luainterpreter.mk
index c37d621..5443477 100644
--- a/package/luainterpreter/luainterpreter.mk
+++ b/package/luainterpreter/luainterpreter.mk
@@ -9,4 +9,10 @@ LUAINTERPRETER_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_LUA_INTERPRET

 LUAINTERPRETER_ABIVER = $(call qstrip,$(BR2_PACKAGE_LUAINTERPRETER_ABI_VERSION))

+ifeq ($(BR2_PACKAGE_HAS_LUA_INTERPRETER),y)
+ifeq ($(LUAINTERPRETER_DEPENDENCIES),)
+$(error No lua interpreter implementation selected. Configuration error.)
+endif
+endif
+
 $(eval $(generic-package))
diff --git a/package/opengl/libegl/libegl.mk b/package/opengl/libegl/libegl.mk
index b2b74f1..3311e50 100644
--- a/package/opengl/libegl/libegl.mk
+++ b/package/opengl/libegl/libegl.mk
@@ -7,11 +7,10 @@
 LIBEGL_SOURCE =
 LIBEGL_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_OPENGL_EGL))

+ifeq ($(BR2_PACKAGE_HAS_OPENGL_EGL),y)
 ifeq ($(LIBEGL_DEPENDENCIES),)
-define LIBEGL_CONFIGURE_CMDS
-	echo "No libEGL implementation selected. Configuration error."
-	exit 1
-endef
+$(error No libEGL implementation selected. Configuration error.)
+endif
 endif

 $(eval $(generic-package))
diff --git a/package/opengl/libgles/libgles.mk b/package/opengl/libgles/libgles.mk
index 0dcbaa7..7a07e37 100644
--- a/package/opengl/libgles/libgles.mk
+++ b/package/opengl/libgles/libgles.mk
@@ -7,11 +7,10 @@
 LIBGLES_SOURCE =
 LIBGLES_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_OPENGL_ES))

+ifeq ($(BR2_PACKAGE_HAS_OPENGL_ES),y)
 ifeq ($(LIBGLES_DEPENDENCIES),)
-define LIBGLES_CONFIGURE_CMDS
-	echo "No libGLES implementation selected. Configuration error."
-	exit 1
-endef
+$(error No libGLES implementation selected. Configuration error.)
+endif
 endif

 $(eval $(generic-package))
diff --git a/package/opengl/libopenmax/libopenmax.mk b/package/opengl/libopenmax/libopenmax.mk
index c4f1f71..a2bd23d 100644
--- a/package/opengl/libopenmax/libopenmax.mk
+++ b/package/opengl/libopenmax/libopenmax.mk
@@ -7,11 +7,10 @@
 LIBOPENMAX_SOURCE =
 LIBOPENMAX_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_OPENMAX))

+ifeq ($(BR2_PACKAGE_HAS_OPENMAX),y)
 ifeq ($(LIBOPENMAX_DEPENDENCIES),)
-define LIBOPENMAX_CONFIGURE_CMDS
-	echo "No libopenmax implementation selected. Configuration error."
-	exit 1
-endef
+$(error No libopenmax implementation selected. Configuration error.)
+endif
 endif

 $(eval $(generic-package))
diff --git a/package/opengl/libopenvg/libopenvg.mk b/package/opengl/libopenvg/libopenvg.mk
index ffd9d68..f81db5e 100644
--- a/package/opengl/libopenvg/libopenvg.mk
+++ b/package/opengl/libopenvg/libopenvg.mk
@@ -7,11 +7,10 @@
 LIBOPENVG_SOURCE =
 LIBOPENVG_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_OPENVG))

+ifeq ($(BR2_PACKAGE_HAS_OPENVG),y)
 ifeq ($(LIBOPENVG_DEPENDENCIES),)
-define LIBOPENVG_CONFIGURE_CMDS
-	echo "No libOpenVG implementation selected. Configuration error."
-	exit 1
-endef
+$(error No libOpenVG implementation selected. Configuration error.)
+endif
 endif

 $(eval $(generic-package))
diff --git a/package/powervr/powervr.mk b/package/powervr/powervr.mk
index 1f43505..b36eb16 100644
--- a/package/powervr/powervr.mk
+++ b/package/powervr/powervr.mk
@@ -7,11 +7,10 @@
 POWERVR_SOURCE =
 POWERVR_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_POWERVR))

+ifeq ($(BR2_PACKAGE_HAS_POWERVR),y)
 ifeq ($(POWERVR_DEPENDENCIES),)
-define POWERVR_CONFIGURE_CMDS
-	echo "No PowerVR implementation selected. Configuration error."
-	exit 1
-endef
+$(error No PowerVR implementation selected. Configuration error.)
+endif
 endif

 $(eval $(generic-package))
--
1.7.9.5

[Buildroot] [PATCH v2 2/2] manual: add virtual package tutorial.

[Eric Le Bihan]

The manual now features a new section with instructions about how to add a
virtual package.

Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
---
 docs/manual/adding-packages-virtual.txt |   99 +++++++++++++++++++++++++++++++
 docs/manual/adding-packages.txt         |    2 +
 2 files changed, 101 insertions(+)
 create mode 100644 docs/manual/adding-packages-virtual.txt

diff --git a/docs/manual/adding-packages-virtual.txt b/docs/manual/adding-packages-virtual.txt
new file mode 100644
index 0000000..10459b8
--- /dev/null
+++ b/docs/manual/adding-packages-virtual.txt
@@ -0,0 +1,99 @@
+// -*- mode:doc; -*-
+// vim: set syntax=asciidoc:
+
+[[virtual-package-tutorial]]
+
+Virtual package tutorial
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+In Buildroot, a virtual package is a package whose functionalities are
+provided by one or more packages, referred to as 'providers'. The virtual
+package management is an extensible mechanism allowing the user to choose
+the provider used in the rootfs.
+
+For example, 'OpenGL ES' is an API for 2D and 3D graphics on embedded systems.
+The implementation of this API is different for the 'Allwinner Tech Sunxi' and
+the 'Texas Instruments OMAP35xx' plaftorms. So +libgles+ will be a virtual
+package and +sunxi-mali+ and +ti-gfx+ will be the providers.
+
+In the following example, we will explain how to add a new virtual package
+('something-virtual') and a provider for it ('some-provider').
+
+First, let's create the virtual package.
+
+Virtual package +Config.in+ file
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The +Config.in+ file of virtual package 'something-virtual' should contain:
+
+---------------------------
+01: config BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
+02:	bool
+03:
+04: config BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL
+05:	depends on BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
+06:	string
+---------------------------
+
+In this file, we declare two options, +BR2_PACKAGE_HAS_SOMETHING_VIRTUAL+ and
++BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL+, whose values will be used by the
+providers.
+
+Virtual package +*.mk+ file
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The Makefile +package/something-virtual/something-virtual.mk+ should contain:
+
+---------------------------
+01: ################################################################################
+02: #
+03: # something-virtual
+04: #
+05: ################################################################################
+06:
+07: SOMETHING_VIRTUAL_SOURCE =
+08: SOMETHING_VIRTUAL_DEPENDENCIES = $(call qstrip,$(BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL))
+09:
+10: ifeq ($(BR2_PACKAGE_HAS_SOMETHING_VIRTUAL),y)
+11: ifeq ($(SOMETHING_VIRTUAL_DEPENDENCIES),)
+12: $(error No something-virtual implementation selected. Configuration error.)
+13: endif
+14: endif
+15:
+16: $(eval $(generic-package))
+---------------------------
+
+The Makefile is quite small as it will only check if a provider for the
+virtual package has been selected.
+
+When adding a package as a provider, only the +Config.in+ file requires some
+modifications. The +*.mk+ file should follow the Buildroot infrastructure with
+no change at all.
+
+Provider +Config.in+ file
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The +Config.in+ file of the package 'some-provider', which provides the
+functionalities of 'something-virtual', should contain:
+
+---------------------------
+01: config BR2_PACKAGE_SOME_PROVIDER
+02:	bool "some-provider"
+03:	select BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
+04:	help
+05:	  This is a comment that explains what some-provider is.
+06:
+07:	  http://foosoftware.org/some-provider/
+08:
+09: if BR2_PACKAGE_SOME_PROVIDER
+10: config BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL
+11:	default "some-provider"
+12: endif
+---------------------------
+
+On line 3, we select +BR2_PACKAGE_HAS_SOMETHING_VIRTUAL+, and on line 11, we
+set the value of +BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL+ to the name of the
+provider, but only if it is selected.
+
+Of course, do not forget to add the proper build and runtime dependencies for
+this package!
diff --git a/docs/manual/adding-packages.txt b/docs/manual/adding-packages.txt
index cc86529..f763282 100644
--- a/docs/manual/adding-packages.txt
+++ b/docs/manual/adding-packages.txt
@@ -22,6 +22,8 @@ include::adding-packages-python.txt[]
 
 include::adding-packages-luarocks.txt[]
 
+include::adding-packages-virtual.txt[]
+
 include::adding-packages-hooks.txt[]
 
 include::adding-packages-gettext.txt[]
-- 
1.7.9.5

[Buildroot] [PATCH v2 1/2] packages: improve dependency check in virtual packages.

[Samuel Martin]

On Tue, Feb 25, 2014 at 4:45 PM, Eric Le Bihan
<eric.le.bihan.dev@free.fr> wrote:
> The current version of dependency check for virtual package <foo>
> defines FOO_CONFIGURE_CMDS to print an error message if the
> dependencies are not met.
>
> This patch updates all the virtual packages to use the GNU Make control
> function $(error text...) instead.
>
> This makes the error happen at the beginning of the build, with a clearer
> message.
>
> Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Reviewed-by: Samuel Martin <s.martin49@gmail.com>

Regards,

-- 
Samuel

[Buildroot] [PATCH v2 2/2] manual: add virtual package tutorial.

[Samuel Martin]

Hi Eric,

On Tue, Feb 25, 2014 at 4:45 PM, Eric Le Bihan
<eric.le.bihan.dev@free.fr> wrote:
[...]
> +
> +Provider +Config.in+ file
> +^^^^^^^^^^^^^^^^^^^^^^^^^
> +
> +The +Config.in+ file of the package 'some-provider', which provides the
> +functionalities of 'something-virtual', should contain:
> +

No word about the provider's *.mk file which does not need any change?

> +---------------------------
> +01: config BR2_PACKAGE_SOME_PROVIDER
> +02:    bool "some-provider"
> +03:    select BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
> +04:    help
> +05:      This is a comment that explains what some-provider is.
> +06:
> +07:      http://foosoftware.org/some-provider/
> +08:
> +09: if BR2_PACKAGE_SOME_PROVIDER
> +10: config BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL
> +11:    default "some-provider"
> +12: endif
> +---------------------------
> +
> +On line 3, we select +BR2_PACKAGE_HAS_SOMETHING_VIRTUAL+, and on line 11, we
> +set the value of +BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL+ to the name of the
> +provider, but only if it is selected.
> +
> +Of course, do not forget to add the proper build and runtime dependencies for
> +this package!
> diff --git a/docs/manual/adding-packages.txt b/docs/manual/adding-packages.txt
> index cc86529..f763282 100644
> --- a/docs/manual/adding-packages.txt
> +++ b/docs/manual/adding-packages.txt
> @@ -22,6 +22,8 @@ include::adding-packages-python.txt[]
>
>  include::adding-packages-luarocks.txt[]
>
> +include::adding-packages-virtual.txt[]
> +
>  include::adding-packages-hooks.txt[]
>
>  include::adding-packages-gettext.txt[]
> --

Otherwise, it looks good! :)

Regards,

-- 
Samuel

[Buildroot] [PATCH v2 1/2] packages: improve dependency check in virtual packages.

[Peter Korsgaard]

>>>>> "Eric" == Eric Le Bihan <eric.le.bihan.dev@free.fr> writes:

 > The current version of dependency check for virtual package <foo>
 > defines FOO_CONFIGURE_CMDS to print an error message if the
 > dependencies are not met.

 > This patch updates all the virtual packages to use the GNU Make control
 > function $(error text...) instead.

 > This makes the error happen at the beginning of the build, with a clearer
 > message.

 > Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
 > Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

Committed to next, thanks.

-- 
Bye, Peter Korsgaard

[Buildroot] [PATCH v2 2/2] manual: add virtual package tutorial.

[Eric Le Bihan]

Hi!

On Tue, Feb 25, 2014 at 09:01:54PM +0100, Samuel Martin wrote:
> Hi Eric,
>
> On Tue, Feb 25, 2014 at 4:45 PM, Eric Le Bihan
> <eric.le.bihan.dev@free.fr> wrote:
> [...]
> > +
> > +Provider +Config.in+ file
> > +^^^^^^^^^^^^^^^^^^^^^^^^^
> > +
> > +The +Config.in+ file of the package 'some-provider', which provides the
> > +functionalities of 'something-virtual', should contain:
> > +
>
> No word about the provider's *.mk file which does not need any change?
I added a line about it, but when I converted the example to plain section, I
have not noticed that the line stayed above the targeted section ("D'Oh"^5)...
Will fix.

Thanks for your reviews!

Best regards,
ELB

[Buildroot] [PATCH v2 1/2] packages: improve dependency check in virtual packages.

[Yann E. MORIN]

Eric, All,

On 2014-02-25 16:45 +0100, Eric Le Bihan spake thusly:
> The current version of dependency check for virtual package <foo>
> defines FOO_CONFIGURE_CMDS to print an error message if the
> dependencies are not met.
> 
> This patch updates all the virtual packages to use the GNU Make control
> function $(error text...) instead.
> 
> This makes the error happen at the beginning of the build, with a clearer
> message.

You missed two virtual packages in this change:
  - jpeg
  - cryptodev

Regards,
Yann E. MORIN.

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCH v2 2/2] manual: add virtual package tutorial.

[Yann E. MORIN]

Eric, All,

On 2014-02-25 16:45 +0100, Eric Le Bihan spake thusly:
> The manual now features a new section with instructions about how to add a
> virtual package.
> 
> Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>

Same comment as Samuel.

Otherwise, I agree with Arnout: we will soon have a virtual-package
infrastructure (see my recent RFC series), and virtual packages are not
something we expect to be added very often.

I know I pushed you to repost an updated version of that patch, so we
could get it in for 2014.02, but in restrospect, Arnout is right: we can
well wait post-release to aply it. My apologies.

Anyway, this patch is rather good, and will need only minor changes (ie.
removals) to the .mk section once we have the virtual-package infra.

Thank you for your work on this! :-)

Regards,
Yann E. MORIN.

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'