From 2b504fe1f6f67bd2d12107c4c00248cb63a35e27 Mon Sep 17 00:00:00 2001 From: Martin Banky Date: Tue, 12 Oct 2010 15:17:54 -0700 Subject: [PATCH] buildroot.html: html code clean-up and other issues - Part2 The current DocType declaration was incorrect. It is neither xhtml strict nor xhtml transitional. So, instead of dealing with that issue, converted it to validated Html5. Fixed white-space errors. Removed validator html4.01 code. Color corrected the code sections. Removed redundant or useless html code. Changed foo to libfoo, for consistency. Changed page bookmarking to use header id's. Re-flowed paragraphs to line break at 80 characters. Re-formatted the code sections for consistency and correctness. Kept all list items, headings, and href's on a single line (where possible). Signed-off-by: Martin Banky Signed-off-by: Peter Korsgaard --- docs/buildroot.html | 1369 ++++++++++++++++++++----------------------- 1 file changed, 649 insertions(+), 720 deletions(-) diff --git a/docs/buildroot.html b/docs/buildroot.html index 5b20e39f4c..5eff1baf64 100644 --- a/docs/buildroot.html +++ b/docs/buildroot.html @@ -808,767 +808,708 @@ config BR2_PACKAGE_LIBFOO categories). The files included there are sorted alphabetically per category and are NOT supposed to contain anything but the bare name of the package.

+ 
 source "package/libfoo/Config.in"
-

The .mk file

- -

Finally, here's the hardest part. Create a file named - foo.mk. It describes how the package should be - downloaded, configured, built, installed, etc.

- -

Depending on the package type, the .mk file must be - written in a different way, using different infrastructures:

- -
    - -
  • Makefiles for generic packages (not using autotools), based - on an infrastructure similar to the one used for autotools-based - packages, but which requires a little more work from the - developer : specify what should be done at for the configuration, - compilation, installation and cleanup of the package. This - infrastructure must be used for all packages that do not use the - autotools as their build system. In the future, other specialized - infrastructures might be written for other build systems.
    We - cover them through a tutorial and a reference.
    • - -
  • Makefiles for autotools-based (autoconf, automake, etc.) - software. We provide a dedicated infrastructure for such - packages, since autotools is a very common build system. This - infrastructure must be used for new packages that rely on - the autotools as their build system.
    We cover them through a - tutorial and a reference.
    • - -
  • Manual Makefiles. These are currently obsolete and no new - manual Makefiles should be added. However, since there are still - many of them in the tree and because the , we keep them documented in a tutorial.
    • - -
- -

Makefile for generic packages : - tutorial

- - 
01: #############################################################
-02: #
-03: # libfoo
-04: #
-05: #############################################################
-06: LIBFOO_VERSION:=1.0
-07: LIBFOO_SOURCE:=libfoo-$(LIBFOO_VERSION).tar.gz
-08: LIBFOO_SITE:=http://www.foosoftware.org/download
-09: LIBFOO_INSTALL_STAGING=YES
-10: LIBFOO_DEPENDENCIES = host-libaaa libbbb
+    
The .mk file

+
+    
Finally, here's the hardest part. Create a file named
+    foo.mk. It describes how the package should be
+    downloaded, configured, built, installed, etc.

+
+    
Depending on the package type, the .mk file must be
+    written in a different way, using different infrastructures:

+
+    
    
+      
  • Makefiles for generic packages (not using autotools), based on an 
+      infrastructure similar to the one used for autotools-based packages, 
+      but which requires a little more work from the developer : specify 
+      what should be done at for the configuration, compilation, installation 
+      and cleanup of the package. This infrastructure must be used for all 
+      packages that do not use the autotools as their build system. In the 
+      future, other specialized infrastructures might be written for other 
+      build systems.
    We cover them through a 
+      tutorial and a 
+      reference.
    • 
+
+      
  • Makefiles for autotools-based (autoconf, automake, etc.) software. 
+      We provide a dedicated infrastructure for such packages, since 
+      autotools is a very common build system. This infrastructure must 
+       be used for new packages that rely on the autotools as their 
+      build system.
    We cover them through a 
+      tutorial and a 
+      reference.
    • 
+
+      
  • Manual Makefiles. These are currently obsolete and no new manual 
+      Makefiles should be added. However, since there are still many of them 
+      in the tree and because the , we keep them documented in a
+      tutorial.
    • 
+    

+
+    
Makefile for generic packages : tutorial

+
+
+01: #############################################################
+02: #
+03: # libfoo
+04: #
+05: #############################################################
+06: LIBFOO_VERSION = 1.0
+07: LIBFOO_SOURCE = libfoo-$(LIBFOO_VERSION).tar.gz
+08: LIBFOO_SITE = http://www.foosoftware.org/download
+09: LIBFOO_INSTALL_STAGING = YES
+10: LIBFOO_DEPENDENCIES = host-libaaa libbbb
 11: 
 12: define LIBFOO_BUILD_CMDS
-13:         $(MAKE) CC=$(TARGET_CC) LD=$(TARGET_LD) -C $(@D) all
+13: 	$(MAKE) CC=$(TARGET_CC) LD=$(TARGET_LD) -C $(@D) all
 14: endef
 15: 
 16: define LIBFOO_INSTALL_STAGING_CMDS
-17:         $(INSTALL) -D $(@D)/libfoo.a $(STAGING_DIR)/usr/lib/libfoo.a
-18:         $(INSTALL) -D $(@D)/foo.h $(STAGING_DIR)/usr/include/foo.h
-19:         cp -dpf $(@D)/libfoo.so* $(STAGING_DIR)/usr/lib
+17: 	$(INSTALL) -D -m 0755 $(@D)/libfoo.a $(STAGING_DIR)/usr/lib/libfoo.a
+18: 	$(INSTALL) -D -m 0644 $(@D)/foo.h $(STAGING_DIR)/usr/include/foo.h
+19: 	$(INSTALL) -D -m 0755 $(@D)/libfoo.so* $(STAGING_DIR)/usr/lib
 20: endef
 21: 
 22: define LIBFOO_INSTALL_TARGET_CMDS
-23:         cp -dpf $(@D)/libfoo.so* $(TARGET_DIR)/usr/lib
-24:         -$(STRIPCMP) $(STRIP_STRIP_UNNEEDED) $(TARGET_DIR)/isr/lib/libfoo.so*
+23: 	$(INSTALL) -D -m 0755 $(@D)/libfoo.so* $(TARGET_DIR)/usr/lib
+24: 	$(INSTALL) -d -m 0755 $(TARGET_DIR)/etc/foo.d
 25: endef
 26: 
-27: $(eval $(call GENTARGETS,package,libfoo))

-
-   
The Makefile begins on line 6 to 8 by metadata informations: the
-   version of the package (LIBFOO_VERSION), the name of
-   the tarball containing the package (LIBFOO_SOURCE) and
-   the Internet location at which the tarball can be downloaded
-   (LIBFOO_SITE). All variables must start with the same
-   prefix, LIBFOO_ in this case. This prefix is always
-   the uppercased version of the package name (see below to understand
-   where the package name is defined).

-
-   
On line 9, we specify that this package wants to install
-   something to the staging space. This is often needed for libraries
-   since they must install header files and other development files in
-   the staging space. This will ensure that the commands listed in the
-   LIBFOO_INSTALL_STAGING_CMDS variable will be
-   executed.

-
-   
On line 10, we specify the list of dependencies this package
-   relies on. These dependencies are listed in terms of lower-case
-   package names, which can be packages for the target (without the
-   host- prefix) or packages for the host (with the
-   host-) prefix). Buildroot will ensure that all these
-   packages are built and installed before the current package
-   starts its configuration.

-
-   
The rest of the Makefile defines what should be done at the
-   different steps of the package configuration, compilation and
-   installation. LIBFOO_BUILD_CMDS tells what steps
-   should be performed to build the
-   package. LIBFOO_INSTALL_STAGING_CMDS tells what steps
-   should be performed to install the package in the staging
-   space. LIBFOO_INSTALL_TARGET_CMDS tells what steps
-   should be performed to install the package in the target space.

-
-   
All these steps rely on the $(@D) variable, which
-   contains the directory where the source code of the package has
-   been extracted.

-
-   
Finally, on line 27, we call the GENTARGETS which
-   generates, according to the variables defined previously, all the
-   Makefile code necessary to make your package working.

-
-   
Makefile for generic packages :
-   reference

-
-   
The GENTARGETS macro takes three arguments:

-
-   
    
-
-     
  • The first argument is the package directory prefix. If your
-     package is in package/libfoo, then the directory
-     prefix is package. If your package is in
-     package/editors/foo, then the directory prefix must
-     be package/editors.
    • 
-
-     
  • The second argument is the lower-cased package name. It must
-     match the prefix of the variables in the .mk file
-     and must match the configuration option name in the
-     Config.in file. For example, if the package name is
-     libfoo, so the variables in the .mk
-     must start with LIBFOO_ and the configuration option
-     in the Config.in file must be
-     BR2_PACKAGE_LIBFOO.
    • 
-
-     
  • The third argument is optional. It can be used to tell if the
-     package if a target package (cross-compiled for the target) or a
-     host package (natively compiled for the host). If unspecified, it
-     is assumed that it is a target package. See below for
-     details.
    • 
-
-   

-
-   
For a given package, in a single .mk file, it is
-   possible to call GENTARGETS twice, once to create the rules to
-   generate a target package and once to create the rules to generate
-   a host package:

+27: $(eval $(call GENTARGETS,package,libfoo))
+
+ +

The Makefile begins on line 6 to 8 by metadata informations: the + version of the package (LIBFOO_VERSION), the name of the + tarball containing the package (LIBFOO_SOURCE) and the + Internet location at which the tarball can be downloaded + (LIBFOO_SITE). All variables must start with the same prefix, + LIBFOO_ in this case. This prefix is always the uppercased + version of the package name (see below to understand where the package + name is defined).

+ +

On line 9, we specify that this package wants to install something to + the staging space. This is often needed for libraries since they must + install header files and other development files in the staging space. + This will ensure that the commands listed in the + LIBFOO_INSTALL_STAGING_CMDS variable will be executed.

+ +

On line 10, we specify the list of dependencies this package relies + on. These dependencies are listed in terms of lower-case package names, + which can be packages for the target (without the host- + prefix) or packages for the host (with the host-) prefix). + Buildroot will ensure that all these packages are built and installed + before the current package starts its configuration.

+ +

The rest of the Makefile defines what should be done at the different + steps of the package configuration, compilation and installation. + LIBFOO_BUILD_CMDS tells what steps should be performed to + build the package. LIBFOO_INSTALL_STAGING_CMDS tells what + steps should be performed to install the package in the staging space. + LIBFOO_INSTALL_TARGET_CMDS tells what steps should be + performed to install the package in the target space.

+ +

All these steps rely on the $(@D) variable, which + contains the directory where the source code of the package has been + extracted.

+ +

Finally, on line 27, we call the GENTARGETS which + generates, according to the variables defined previously, all the + Makefile code necessary to make your package working.

+ +

Makefile for generic packages : reference

+ +

The GENTARGETS macro takes three arguments:

+ +
    +
  • The first argument is the package directory prefix. If your + package is in package/libfoo, then the directory prefix + is package. If your package is in + package/editors/foo, then the directory prefix must be + package/editors.
    • + +
  • The second argument is the lower-cased package name. It must match + the prefix of the variables in the .mk file and must + match the configuration option name in the Config.in + file. For example, if the package name is libfoo, so the + variables in the .mk must start with + LIBFOO_ and the configuration option in the + Config.in file must be BR2_PACKAGE_LIBFOO.
    • + +
  • The third argument is optional. It can be used to tell if the + package if a target package (cross-compiled for the target) or a host + package (natively compiled for the host). If unspecified, it is + assumed that it is a target package. See below for details.
    • +
+ +

For a given package, in a single .mk file, it is + possible to call GENTARGETS twice, once to create the rules to generate + a target package and once to create the rules to generate a host package: + 

 $(eval $(call GENTARGETS,package,libfoo))
 $(eval $(call GENTARGETS,package,libfoo,host))
-

This might be useful if the compilation of the target package - requires some tools to be installed on the host. If the package - name is libfoo, then the name of the package for the - target is also libfoo, while the name of the package - for the host is host-libfoo. These names should be - used in the DEPENDENCIES variables of other packages if they depend - on libfoo or host-libfoo.

- -

The call to the GENTARGETS macro must be at - the end of the .mk file, after all variable - definitions.

- -

For the target package, the GENTARGETS uses the - variables defined by the .mk file and prefixed by the uppercased - package name: LIBFOO_*. For the host package, it uses - the HOST_LIBFOO_*. For some variables, if the - HOST_LIBFOO_ prefixed variable doesn't exist, the - package infrastructure uses the corresponding variable prefixed by - LIBFOO_. This is done for variables that are likely to - have the same value for both the target and host packages. See - below for details.

- -

The list of variables that can be set in a .mk file - to give metadata informations is (assuming the package name is - libfoo) :

- -
    - -
  • LIBFOO_VERSION, mandatory, must contain the - version of the package. Note that if - HOST_LIBFOO_VERSION doesn't exist, it is assumed to - be the same as LIBFOO_VERSION.
    Example: - LIBFOO_VERSION=0.1.2
    • - -
  • LIBFOO_SOURCE may contain the name of the - tarball of the package. If HOST_LIBFOO_SOURCE is not - specified, it defaults to LIBFOO_VERSION. If none - are specified, then the value is assumed to be - packagename-$(LIBFOO_VERSION).tar.gz.
    Example: - LIBFOO_SOURCE = - foobar-$(LIBFOO_VERSION).tar.bz2
    • - -
  • LIBFOO_PATCH may contain the name of a patch, - that will be downloaded from the same location as the tarball - indicated in LIBFOO_SOURCE. If - HOST_LIBFOO_PATCH is not specified, it defaults to - LIBFOO_PATCH. Also note that another mechanism is - available to patch a package: all files of the form - packagename-packageversion-description.patch present - in the package directory inside Buildroot will be applied to the - package after extraction.
    • - -
  • LIBFOO_SITE may contain the Internet location of - the tarball of the package. If HOST_LIBFOO_SITE is - not specified, it defaults to LIBFOO_SITE. If none - are specified, then the location is assumed to be - http://$$(BR2_SOURCEFORGE_MIRROR).dl.sourceforge.net/sourceforge/packagename.
    Example: - LIBFOO_SITE=http://www.foosoftware.org/libfoo.
    • - -
  • LIBFOO_DEPENDENCIES lists the dependencies (in - terms of package name) that are required for the current target - package to compile. These dependencies are guaranteed to be - compiled and installed before the configuration of the current - package starts. In a similar way, - HOST_LIBFOO_DEPENDENCIES lists the dependency for - the current host package.
    • - -
  • LIBFOO_INSTALL_STAGING can be set to - YES or NO (default). If set to - YES, then the commands in the - LIBFOO_INSTALL_STAGING_CMDS variables are executed - to install the package into the staging directory.

    - -
  • LIBFOO_INSTALL_TARGET can be set to - YES (default) or NO. If set to - YES, then the commands in the - LIBFOO_INSTALL_TARGET_CMDS variables are executed - to install the package into the target directory.

    - -
- -

The recommended way to define these variables is to use the - following syntax:

+

This might be useful if the compilation of the target package + requires some tools to be installed on the host. If the package name is + libfoo, then the name of the package for the target is also + libfoo, while the name of the package for the host is + host-libfoo. These names should be used in the DEPENDENCIES + variables of other packages if they depend on libfoo or + host-libfoo.

+ +

The call to the GENTARGETS macro must be at the + end of the .mk file, after all variable definitions.

+ +

For the target package, the GENTARGETS uses the + variables defined by the .mk file and prefixed by the uppercased package + name: LIBFOO_*. For the host package, it uses the + HOST_LIBFOO_*. For some variables, if the + HOST_LIBFOO_ prefixed variable doesn't exist, the package + infrastructure uses the corresponding variable prefixed by + LIBFOO_. This is done for variables that are likely to have + the same value for both the target and host packages. See below for + details.

+ +

The list of variables that can be set in a .mk file to + give metadata informations is (assuming the package name is + libfoo) :

+ +
    +
  • LIBFOO_VERSION, mandatory, must contain the version + of the package. Note that if HOST_LIBFOO_VERSION doesn't + exist, it is assumed to be the same as LIBFOO_VERSION. +
    Example: LIBFOO_VERSION=0.1.2
    • + +
  • LIBFOO_SOURCE may contain the name of the tarball of + the package. If HOST_LIBFOO_SOURCE is not specified, it + defaults to LIBFOO_VERSION. If none are specified, then + the value is assumed to be + packagename-$(LIBFOO_VERSION).tar.gz.
    Example: + LIBFOO_SOURCE = foobar-$(LIBFOO_VERSION).tar.bz2
    • + +
  • LIBFOO_PATCH may contain the name of a patch, that + will be downloaded from the same location as the tarball indicated in + LIBFOO_SOURCE. If HOST_LIBFOO_PATCH is not + specified, it defaults to LIBFOO_PATCH. Also note that + another mechanism is available to patch a package: all files of the + form packagename-packageversion-description.patch present + in the package directory inside Buildroot will be applied to the + package after extraction.
    • + +
  • LIBFOO_SITE may contain the Internet location of the + tarball of the package. If HOST_LIBFOO_SITE is not + specified, it defaults to LIBFOO_SITE. If none are + specified, then the location is assumed to be + http://$$(BR2_SOURCEFORGE_MIRROR).dl.sourceforge.net/sourceforge/packagename. +
    Example: + LIBFOO_SITE=http://www.foosoftware.org/libfoo.
    • + +
  • LIBFOO_DEPENDENCIES lists the dependencies (in terms + of package name) that are required for the current target package to + compile. These dependencies are guaranteed to be compiled and + installed before the configuration of the current package starts. In a + similar way, HOST_LIBFOO_DEPENDENCIES lists the + dependency for the current host package.
    • + +
  • LIBFOO_INSTALL_STAGING can be set to YES + or NO (default). If set to YES, then the + commands in the LIBFOO_INSTALL_STAGING_CMDS variables are + executed to install the package into the staging directory.
    • + +
  • LIBFOO_INSTALL_TARGET can be set to YES + (default) or NO. If set to YES, then the + commands in the LIBFOO_INSTALL_TARGET_CMDS variables are + executed to install the package into the target directory.
+ +

The recommended way to define these variables is to use the following + syntax:

 LIBFOO_VERSION=2.32
-

Now, the variables that define what should be performed at the - different steps of the build process.

- -
    - -
  • LIBFOO_CONFIGURE_CMDS, used to list the - actions to be performed to configure the package before its - compilation
    • - -
  • LIBFOO_BUILD_CMDS, used to list the actions to - be performed to compile the package
    • - -
  • HOST_LIBFOO_INSTALL_CMDS, used to list the - actions to be performed to install the package, when the - package is a host package. The package must install its files - to the directory given by $(HOST_DIR). All files, - including development files such as headers should be - installed, since other packages might be compiled on top of - this package.
    • - -
  • LIBFOO_INSTALL_TARGET_CMDS, used to list the - actions to be performed to install the package to the target - directory, when the package is a target package. The package - must install its files to the directory given by - $(TARGET_DIR). Only the files required for - execution of the package should be installed. Header - files and documentation should not be installed.
    • +

    Now, the variables that define what should be performed at the + different steps of the build process.

    -
  • LIBFOO_INSTALL_STAGING_CMDS, used to list the - actions to be performed to install the package to the staging - directory, when the package is a target package. The package - must install its files to the directory given by - $(STAGING_DIR). All development files should be - installed, since they might be needed to compile other - packages.
    • - -
  • LIBFOO_CLEAN_CMDS, used to list the actions to - perform to clean up the build directory of the package.
    • - -
  • LIBFOO_UNINSTALL_TARGET_CMDS, used to list the - actions to uninstall the package from the target directory - $(TARGET_DIR)
    • - -
  • LIBFOO_UNINSTALL_STAGING_CMDS
    • , used to - list the actions to uninstall the package from the staging - directory $(STAGING_DIR). - -
+
    +
  • LIBFOO_CONFIGURE_CMDS, used to list the actions to be + performed to configure the package before its compilation
    • + +
  • LIBFOO_BUILD_CMDS, used to list the actions to be + performed to compile the package
    • + +
  • HOST_LIBFOO_INSTALL_CMDS, used to list the actions to + be performed to install the package, when the package is a host + package. The package must install its files to the directory given by + $(HOST_DIR). All files, including development files such + as headers should be installed, since other packages might be compiled + on top of this package.
    • + +
  • LIBFOO_INSTALL_TARGET_CMDS, used to list the actions + to be performed to install the package to the target directory, when + the package is a target package. The package must install its files to + the directory given by $(TARGET_DIR). Only the files + required for execution of the package + should be installed. Header files and documentation should not be + installed.
    • + +
  • LIBFOO_INSTALL_STAGING_CMDS, used to list the actions + to be performed to install the package to the staging directory, when + the package is a target package. The package must install its files to + the directory given by $(STAGING_DIR). All development + files should be installed, since they might be needed to compile other + packages.
    • + +
  • LIBFOO_CLEAN_CMDS, used to list the actions to + perform to clean up the build directory of the package.
    • + +
  • LIBFOO_UNINSTALL_TARGET_CMDS, used to list the actions + to uninstall the package from the target directory + $(TARGET_DIR)
    • + +
  • LIBFOO_UNINSTALL_STAGING_CMDS, used to list the + actions to uninstall the package from the staging directory + $(STAGING_DIR).
    • +
-

The preferred way to define these variables is:

+

The preferred way to define these variables is:

 define LIBFOO_CONFIGURE_CMDS
- action 1
- action 2
- action 3
-endef
- -

In the action definitions, you can use the following - variables:

- -
    - -
  • $(@D), which contains the directory in which - the package source code has been uncompressed.
    • + action 1 + action 2 + action 3 +endef + -
  • $(TARGET_CC), $(TARGET_LD), - etc. to get the target cross-compilation utilities
    • +

    In the action definitions, you can use the following variables:

    -
  • $(TARGET_CROSS) to get the cross-compilation - toolchain prefix
    • +
      +
    • $(@D), which contains the directory in which the + package source code has been uncompressed.
      • -
    • Of course the $(HOST_DIR), - $(STAGING_DIR) and $(TARGET_DIR) - variables to install the packages properly.
      • +
    • $(TARGET_CC), $(TARGET_LD), etc. to get + the target cross-compilation utilities
      • -
    +
  • $(TARGET_CROSS) to get the cross-compilation + toolchain prefix
    • +
  • Of course the $(HOST_DIR), $(STAGING_DIR) + and $(TARGET_DIR) variables to install the packages + properly.
    • +
-

The last feature of the generic infrastructure is the ability - to add hook more actions after existing steps. These hooks aren't - really useful for generic packages, since the .mk - file already has full control over the actions performed in each - step of the package construction. The hooks are more useful for - packages using the autotools infrastructure described below. But - since they are provided by the generic infrastructure, they are - documented here.

+

The last feature of the generic infrastructure is the ability to add + hook more actions after existing steps. These hooks aren't really useful + for generic packages, since the .mk file already has full + control over the actions performed in each step of the package + construction. The hooks are more useful for packages using the autotools + infrastructure described below. But since they are provided by the + generic infrastructure, they are documented here.

-

The following hook points are available:

+

The following hook points are available:

-
    -
  • LIBFOO_POST_PATCH_HOOKS
    • -
  • LIBFOO_POST_CONFIGURE_HOOKS
    • -
  • LIBFOO_POST_BUILD_HOOKS
    • -
  • LIBFOO_POST_INSTALL_HOOKS (for host packages only)
    • -
  • LIBFOO_POST_INSTALL_STAGING_HOOKS (for target packages only)
    • -
  • LIBFOO_POST_INSTALL_TARGET_HOOKS (for target packages only)
    • -
+
    +
  • LIBFOO_POST_PATCH_HOOKS
    • +
  • LIBFOO_POST_CONFIGURE_HOOKS
    • +
  • LIBFOO_POST_BUILD_HOOKS
    • +
  • LIBFOO_POST_INSTALL_HOOKS (for host packages only)
    • +
  • LIBFOO_POST_INSTALL_STAGING_HOOKS (for target packages only)
    • +
  • LIBFOO_POST_INSTALL_TARGET_HOOKS (for target packages only)
    • +
-

This variables are lists of variable names containing - actions to be performed at this hook point. This allows several - hooks to be registered at a given hook point. Here is an - example:

+

This variables are lists of variable names containing actions + to be performed at this hook point. This allows several hooks to be + registered at a given hook point. Here is an example:

- 
+
 define LIBFOO_POST_PATCH_FIXUP
-  action1
-  action2
+	action1
+	action2
 endef
 
 LIBFOO_POST_PATCH_HOOKS += LIBFOO_POST_PATCH_FIXUP
 

 
-   
Makefile for autotools-based
-   packages : tutorial

-
-   
First, let's see how to write a .mk file for an
-   autotools-based package, with an example :

-
-
01: #############################################################
-02: #
-03: # foo
-04: #
-05: #############################################################
-06: 
-07: FOO_VERSION:=1.0
-08: FOO_SOURCE:=foo-$(FOO_VERSION).tar.gz
-09: FOO_SITE:=http://www.foosoftware.org/downloads
-10: FOO_INSTALL_STAGING = YES
-11: FOO_INSTALL_TARGET = YES
-12: FOO_CONF_OPT =  --enable-shared
-13: FOO_DEPENDENCIES = libglib2 host-pkg-config
-14: 
-15: $(eval $(call AUTOTARGETS,package,foo))

-
-    
On line 7, we declare the version of the package. On line 8 and
-    9, we declare the name of the tarball and the location of the
-    tarball on the Web. Buildroot will automatically download the
+   
Makefile for autotools-based packages : tutorial

+
+   
First, let's see how to write a .mk file for an 
+   autotools-based package, with an example :

+
+
+01: #############################################################
+02: #
+03: # libfoo
+04: #
+05: #############################################################
+06: LIBFOO_VERSION = 1.0
+07: LIBFOO_SOURCE = libfoo-$(LIBFOO_VERSION).tar.gz
+08: LIBFOO_SITE = http://www.foosoftware.org/download
+09: LIBFOO_INSTALL_STAGING = YES
+10: LIBFOO_INSTALL_TARGET = YES
+11: LIBFOO_CONF_OPT = --enable-shared
+12: LIBFOO_DEPENDENCIES = libglib2 host-pkg-config
+13:
+14: $(eval $(call AUTOTARGETS,package,libfoo))
+

+
+    
On line 6, we declare the version of the package.

+    
+    
On line 7 and 8, we declare the name of the tarball and the location 
+    of the tarball on the Web. Buildroot will automatically download the 
     tarball from this location.

 
-    
On line 10, we tell Buildroot to install the package to the
-    staging directory. The staging directory, located in
-    output/staging/ is the directory where all the
-    packages are installed, including their development files, etc. By
-    default, packages are not installed to the staging directory,
-    since usually, only libraries need to be installed in the staging
-    directory: their development files are needed to compile other
-    libraries or applications depending on them. Also by default, when
-    staging installation is enabled, packages are installed in this
-    location using the make install command.

-
-    
On line 11, we tell Buildroot to also install the package to
-    the target directory. This directory contains what will become the
-    root filesystem running on the target. Usually, we try not to
-    install the documentation and to install stripped versions of the
-    binary. By default, target installation is enabled, so in fact,
-    this line is not strictly necessary. Also by default, packages are
-    installed in this location using the make
-    install-strip command.

-
-    
On line 12, we tell Buildroot to pass a custom configure
-    option, that will be passed to the ./configure script
-    before configuring and building the package.

-
-    
On line 13, we declare our dependencies, so that they are built
+    
On line 9, we tell Buildroot to install the package to the staging 
+    directory. The staging directory, located in output/staging/
+    is the directory where all the packages are installed, including their 
+    development files, etc. By default, packages are not installed to the 
+    staging directory, since usually, only libraries need to be installed in 
+    the staging directory: their development files are needed to compile 
+    other libraries or applications depending on them. Also by default, when 
+    staging installation is enabled, packages are installed in this location 
+    using the make install command.

+
+    
On line 10, we tell Buildroot to also install the package to the 
+    target directory. This directory contains what will become the root 
+    filesystem running on the target. Usually, we try not to install header 
+    files and to install stripped versions of the binary. By default, target 
+    installation is enabled, so in fact, this line is not strictly 
+    necessary. Also by default, packages are installed in this location 
+    using the make install command.

+
+    
On line 11, we tell Buildroot to pass a custom configure option, that 
+    will be passed to the ./configure script before configuring 
+    and building the package.

+
+    
On line 12, we declare our dependencies, so that they are built 
     before the build process of our package starts.

 
-    
Finally, on line line 14, we invoke the
-    AUTOTARGETS macro that generates all the Makefile
-    rules that actually allows the package to be built.

-
-    
Makefile for autotools
-    packages : reference

-
-    
The main macro of the autotools package infrastructure is
-    AUTOTARGETS. It has the same number of arguments and
-    the same semantic as the GENTARGETS macro, which is
-    the main macro of the generic package infrastructure. For
-    autotools packages, the ability to have target and host packages
-    is also available (and is actually widely used).

-
-    
Just like the generic infrastructure, the autotools
-    infrastructure works by defining a number of variables before
-    calling the AUTOTARGETS macro.

-
-    
First, all the package meta-information variables that exist in
-    the generic infrastructure also exist in the autotools
-    infrastructure: LIBFOO_VERSION,
-    LIBFOO_SOURCE, LIBFOO_PATCH,
-    LIBFOO_SITE, LIBFOO_SUBDIR,
-    LIBFOO_DEPENDENCIES,
-    LIBFOO_INSTALL_STAGING,
-    LIBFOO_INSTALL_TARGET.

-
-    
A few additional variables, specific to the autotools
-    infrastructure, can also be defined. Many of them are only useful
-    in very specific cases, typical packages will therefore only use a
-    few of them.

+    
Finally, on line line 14, we invoke the AUTOTARGETS 
+    macro that generates all the Makefile rules that actually allows the 
+    package to be built.

 
-    
    
+    
    Makefile for autotools packages : reference
    
 
-      
  • LIBFOO_SUBDIR may contain the name of a
-      subdirectory inside the package that contains the configure
-      script. This is useful, if for example, the main configure
-      script is not at the root of the tree extracted by the
-      tarball. If HOST_LIBFOO_SUBDIR is not specified, it
-      defaults to LIBFOO_SUBDIR.
    • 
-
-      
  • LIBFOO_CONF_ENV, to specify additional
-      environment variables to pass to the configure script. By
-      default, empty.
    • 
-
-      
  • LIBFOO_CONF_OPT, to specify additional
-      configure options to pass to the configure script. By default,
-      empty.
    • 
-
-      
  • LIBFOO_MAKE, to specify an
-      alternate make command. This is typically useful
-      when parallel make it enabled in the configuration
-      (using BR2_JLEVEL) but that this feature should be
-      disabled for the given package, for one reason or another. By
-      default, set to $(MAKE). If parallel building is
-      not supported by the package, then it should
-      do LIBFOO_MAKE=$(MAKE1).
    • 
-
-      
  • LIBFOO_MAKE_ENV, to specify additional
-      environment variables to pass to make in the build step. These
-      are passed before the make command. By default,
-      empty.
    • 
-
-      
  • LIBFOO_MAKE_OPT, to specify additional
-      variables to pass to make in the build step. These are passed
-      after the make command. By default, empty.
    • 
-
-      
  • LIBFOO_AUTORECONF, tells whether the package
-      should be autoreconfigured or not (i.e, if the configure script
-      and Makefile.in files should be re-generated by re-running
-      autoconf, automake, libtool, etc.). Valid values
-      are YES and NO. By default, the value
-      is NO
    • 
-
-      
  • LIBFOO_AUTORECONF_OPT to specify additional
-      options passed to the autoreconf program
-      if LIBFOO_AUTORECONF=YES. By default, empty.
    • 
-
-      
  • LIBFOO_LIBTOOL_PATCH tells whether the
-      Buildroot patch to fix libtool cross-compilation issues should
-      be applied or not. Valid values are YES
-      and NO. By default, the value
-      is YES
    • 
-
-      
  • LIBFOO_USE_CONFIG_CACHE tells whether the
-      configure script should really on a cache file that caches test
-      results from previous configure script. Usually, this variable
-      should be left to its default value. Only for specific packages
-      having issues with the configure cache can set this variable to
-      the NO value (but this is more a work-around than a
-      really fix)
    • 
-
-      
  • LIBFOO_INSTALL_STAGING_OPT contains the make
-      options used to install the package to the staging directory. By
-      default, the value is DESTDIR=$$(STAGING_DIR)
-      install, which is correct for most autotools packages. It
-      is still possible to override it.
    • 
-
-      
  • LIBFOO_INSTALL_TARGET_OPT contains the make
-      options used to install the package to the target directory. By
-      default, the value is DESTDIR=$$(TARGET_DIR)
-      install-strip if BR2_ENABLE_DEBUG is not
-      set, and DESTDIR=$$(TARGET_DIR) install-exec
-      if BR2_ENABLE_DEBUG is set. These default values
-      are correct for most autotools packages, but it is still
-      possible to override them if needed.
    • 
-
-      
  • LIBFOO_CLEAN_OPT contains the make options used
-      to clean the package. By default, the value
-      is clean.
    • 
-
-      
  • LIBFOO_UNINSTALL_STAGING_OPT, contains the make
-      options used to uninstall the package from the staging
-      directory. By default, the value is
-      DESTDIR=$$(STAGING_DIR) uninstall.
    • 
-
-      
  • LIBFOO_UNINSTALL_TARGET_OPT, contains the make
-      options used to uninstall the package from the target
-      directory. By default, the value is
-      DESTDIR=$$(TARGET_DIR) uninstall.
    • 
+    
    The main macro of the autotools package infrastructure is 
+    AUTOTARGETS. It has the same number of arguments and the 
+    same semantic as the GENTARGETS macro, which is the main 
+    macro of the generic package infrastructure. For autotools packages, the 
+    ability to have target and host packages is also available (and is 
+    actually widely used).
    
 
-    

+    
Just like the generic infrastructure, the autotools infrastructure 
+    works by defining a number of variables before calling the 
+    AUTOTARGETS macro.

 
-    
With the autotools infrastructure, all the steps required to
-    build and install the packages are already defined, and they
-    generally work well for most autotools-based packages. However,
-    when required, it is still possible to customize what is done in
-    particular step:

+    
First, all the package meta-information variables that exist in the 
+    generic infrastructure also exist in the autotools infrastructure: 
+    LIBFOO_VERSION, LIBFOO_SOURCE, 
+    LIBFOO_PATCH, LIBFOO_SITE, 
+    LIBFOO_SUBDIR, LIBFOO_DEPENDENCIES, 
+    LIBFOO_INSTALL_STAGING, LIBFOO_INSTALL_TARGET.

 
-    
    
+    
    A few additional variables, specific to the autotools infrastructure, 
+    can also be defined. Many of them are only useful in very specific 
+    cases, typical packages will therefore only use a few of them.
    
 
-      
  • By adding a post-operation hook (after extract, patch,
-      configure, build or install). See the reference documentation of
-      the generic infrastructure for details.
    • 
+    
      
+      
    • LIBFOO_SUBDIR may contain the name of a subdirectory 
+      inside the package that contains the configure script. This is useful, 
+      if for example, the main configure script is not at the root of the 
+      tree extracted by the tarball. If HOST_LIBFOO_SUBDIR is 
+      not specified, it defaults to LIBFOO_SUBDIR.
      • 
+
+      
    • LIBFOO_CONF_ENV, to specify additional environment 
+      variables to pass to the configure script. By default, empty.
      • 
+
+      
    • LIBFOO_CONF_OPT, to specify additional configure 
+      options to pass to the configure script. By default, empty.
      • 
+
+      
    • LIBFOO_MAKE, to specify an alternate make
+      command. This is typically useful when parallel make it enabled in 
+      the configuration (using BR2_JLEVEL) but that this 
+      feature should be disabled for the given package, for one reason or 
+      another. By default, set to $(MAKE). If parallel building 
+      is not supported by the package, then it should do 
+      LIBFOO_MAKE=$(MAKE1).
      • 
+
+      
    • LIBFOO_MAKE_ENV, to specify additional environment 
+      variables to pass to make in the build step. These are passed before 
+      the make command. By default, empty.
      • 
+
+      
    • LIBFOO_MAKE_OPT, to specify additional variables to 
+      pass to make in the build step. These are passed after the 
+      make command. By default, empty.
      • 
+
+      
    • LIBFOO_AUTORECONF, tells whether the package should 
+      be autoreconfigured or not (i.e, if the configure script and 
+      Makefile.in files should be re-generated by re-running autoconf, 
+      automake, libtool, etc.). Valid values are YES and 
+      NO. By default, the value is NO
      • 
+
+      
    • LIBFOO_AUTORECONF_OPT to specify additional options 
+      passed to the autoreconf program if 
+      LIBFOO_AUTORECONF=YES. By default, empty.
      • 
+
+      
    • LIBFOO_LIBTOOL_PATCH tells whether the Buildroot 
+      patch to fix libtool cross-compilation issues should be applied or 
+      not. Valid values are YES and NO. By 
+      default, the value is YES
      • 
+
+      
    • LIBFOO_USE_CONFIG_CACHE tells whether the configure 
+      script should really on a cache file that caches test results from 
+      previous configure script. Usually, this variable should be left to 
+      its default value. Only for specific packages having issues with the 
+      configure cache can set this variable to the NO value 
+      (but this is more a work-around than a really fix)
      • 
+
+      
    • LIBFOO_INSTALL_STAGING_OPT contains the make options 
+      used to install the package to the staging directory. By default, the 
+      value is DESTDIR=$$(STAGING_DIR) install, which is 
+      correct for most autotools packages. It is still possible to override 
+      it.
      • 
+
+      
    • LIBFOO_INSTALL_TARGET_OPT contains the make options 
+      used to install the package to the target directory. By default, the 
+      value is DESTDIR=$$(TARGET_DIR) install-strip if 
+      BR2_ENABLE_DEBUG is not set, and 
+      DESTDIR=$$(TARGET_DIR) install-exec if 
+      BR2_ENABLE_DEBUG is set. These default values are correct 
+      for most autotools packages, but it is still possible to override them 
+      if needed.
      • 
+
+      
    • LIBFOO_CLEAN_OPT contains the make options used to 
+      clean the package. By default, the value is clean.
      • 
+
+      
    • LIBFOO_UNINSTALL_STAGING_OPT, contains the make 
+      options used to uninstall the package from the staging directory. By 
+      default, the value is DESTDIR=$$(STAGING_DIR) uninstall.
      • 
+
+      
    • LIBFOO_UNINSTALL_TARGET_OPT, contains the make 
+      options used to uninstall the package from the target directory. By 
+      default, the value is DESTDIR=$$(TARGET_DIR) uninstall.
      • 
+    
    
 
-      
  • By overriding one of the steps. For example, even if the
-      autotools infrastructure is used, if the package
-      .mk defines its own
-      LIBFOO_CONFIGURE_CMDS variable, it will be used
-      instead of the default autotools one. However, using this method
-      should be restricted to very specific cases. Do not use it in
-      the general case.
    • 
+    
    With the autotools infrastructure, all the steps required to build 
+    and install the packages are already defined, and they generally work 
+    well for most autotools-based packages. However, when required, it is 
+    still possible to customize what is done in particular step:
    
 
+    
      
+      
    • By adding a post-operation hook (after extract, patch, configure, 
+      build or install). See the reference documentation of the generic 
+      infrastructure for details.
      • 
+
+      
    • By overriding one of the steps. For example, even if the autotools 
+      infrastructure is used, if the package .mk defines its 
+      own LIBFOO_CONFIGURE_CMDS variable, it will be used 
+      instead of the default autotools one. However, using this method 
+      should be restricted to very specific cases. Do not use it in the 
+      general case.
      • 
     
    
 
-    
    Manual Makefile : tutorial
    
+    
    Manual Makefile : tutorial
    
 
-    
    NOTE: new manual makefiles should not be created, and
-    existing manual makefiles should be converted either to the
-    generic infrastructure or the autotools infrastructure. This
-    section is only kept to document the existing manual makefiles and
-    help understanding how they work.
    
+    
    NOTE: new manual makefiles should not be created, and existing 
+    manual makefiles should be converted either to the generic 
+    infrastructure or the autotools infrastructure. This section is only 
+    kept to document the existing manual makefiles and help understanding 
+    how they work.
    
 
 
    -     1  #############################################################
-     2  #
-     3  # foo
-     4  #
-     5  #############################################################
-     6  FOO_VERSION:=1.0
-     7  FOO_SOURCE:=foo-$(FOO_VERSION).tar.gz
-     8  FOO_SITE:=http://www.foosoftware.org/downloads
-     9  FOO_DIR:=$(BUILD_DIR)/foo-$(FOO_VERSION)
-    10  FOO_BINARY:=foo
-    11  FOO_TARGET_BINARY:=usr/bin/foo
-    12
-    13  $(DL_DIR)/$(FOO_SOURCE):
-    14          $(call DOWNLOAD,$(FOO_SITE),$(FOO_SOURCE))
-    15
-    16  $(FOO_DIR)/.source: $(DL_DIR)/$(FOO_SOURCE)
-    17          $(ZCAT) $(DL_DIR)/$(FOO_SOURCE) | tar -C $(BUILD_DIR) $(TAR_OPTIONS) -
-    18          touch $@
-    19
-    20  $(FOO_DIR)/.configured: $(FOO_DIR)/.source
-    21          (cd $(FOO_DIR); rm -rf config.cache; \
-    22                  $(TARGET_CONFIGURE_OPTS) \
-    23                  $(TARGET_CONFIGURE_ARGS) \
-    24                  ./configure \
-    25                  --target=$(GNU_TARGET_NAME) \
-    26                  --host=$(GNU_TARGET_NAME) \
-    27                  --build=$(GNU_HOST_NAME) \
-    28                  --prefix=/usr \
-    29                  --sysconfdir=/etc \
-    30          )
-    31          touch $@
-    32
-    33  $(FOO_DIR)/$(FOO_BINARY): $(FOO_DIR)/.configured
-    34          $(MAKE) CC=$(TARGET_CC) -C $(FOO_DIR)
-    35
-    36  $(TARGET_DIR)/$(FOO_TARGET_BINARY): $(FOO_DIR)/$(FOO_BINARY)
-    37          $(MAKE) DESTDIR=$(TARGET_DIR) -C $(FOO_DIR) install-strip
-    38          rm -Rf $(TARGET_DIR)/usr/man
-    39
-    40  foo: uclibc ncurses $(TARGET_DIR)/$(FOO_TARGET_BINARY)
-    41
-    42  foo-source: $(DL_DIR)/$(FOO_SOURCE)
-    43
-    44  foo-clean:
-    45          $(MAKE) prefix=$(TARGET_DIR)/usr -C $(FOO_DIR) uninstall
-    46          -$(MAKE) -C $(FOO_DIR) clean
-    47
-    48  foo-dirclean:
-    49          rm -rf $(FOO_DIR)
-    50
-    51 #############################################################
-    52 #
-    53 # Toplevel Makefile options
-    54 #
-    55 #############################################################
-    56 ifeq ($(BR2_PACKAGE_FOO),y)
-    57 TARGETS+=foo
-    58 endif
-
+01: #############################################################
+02: #
+03: # libfoo
+04: #
+05: #############################################################
+06: LIBFOO_VERSION:=1.0
+07: LIBFOO_SOURCE:=libfoo-$(LIBFOO_VERSION).tar.gz
+08: LIBFOO_SITE:=http://www.foosoftware.org/downloads
+09: LIBFOO_DIR:=$(BUILD_DIR)/foo-$(FOO_VERSION)
+10: LIBFOO_BINARY:=foo
+11: LIBFOO_TARGET_BINARY:=usr/bin/foo
+12:
+13: $(DL_DIR)/$(LIBFOO_SOURCE):
+14: 	$(call DOWNLOAD,$(LIBFOO_SITE),$(LIBFOO_SOURCE))
+15:
+16: $(LIBFOO_DIR)/.source: $(DL_DIR)/$(LIBFOO_SOURCE)
+17: 	$(ZCAT) $(DL_DIR)/$(LIBFOO_SOURCE) | tar -C $(BUILD_DIR) $(TAR_OPTIONS) -
+18: 	touch $@
+19:
+20: $(LIBFOO_DIR)/.configured: $(LIBFOO_DIR)/.source
+21: 	(cd $(LIBFOO_DIR); rm -rf config.cache; \
+22: 		$(TARGET_CONFIGURE_OPTS) \
+23: 		$(TARGET_CONFIGURE_ARGS) \
+24: 		./configure \
+25: 		--target=$(GNU_TARGET_NAME) \
+26: 		--host=$(GNU_TARGET_NAME) \
+27: 		--build=$(GNU_HOST_NAME) \
+28: 		--prefix=/usr \
+29: 		--sysconfdir=/etc \
+30: 	)
+31: 	touch $@
+32:
+33: $(LIBFOO_DIR)/$(LIBFOO_BINARY): $(LIBFOO_DIR)/.configured
+34: 	$(MAKE) CC=$(TARGET_CC) -C $(LIBFOO_DIR)
+35:
+36: $(TARGET_DIR)/$(LIBFOO_TARGET_BINARY): $(LIBFOO_DIR)/$(LIBFOO_BINARY)
+37: 	$(MAKE) DESTDIR=$(TARGET_DIR) -C $(LIBFOO_DIR) install-strip
+38: 	rm -Rf $(TARGET_DIR)/usr/man
+39:
+40: libfoo: uclibc ncurses $(TARGET_DIR)/$(LIBFOO_TARGET_BINARY)
+41:
+42: libfoo-source: $(DL_DIR)/$(LIBFOO_SOURCE)
+43:
+44: libfoo-clean:
+45: 	$(MAKE) prefix=$(TARGET_DIR)/usr -C $(LIBFOO_DIR) uninstall
+46: 	-$(MAKE) -C $(LIBFOO_DIR) clean
+47:
+48: libfoo-dirclean:
+49: 	rm -rf $(LIBFOO_DIR)
+50:
+51: #############################################################
+52: #
+53: # Toplevel Makefile options
+54: #
+55: #############################################################
+56: ifeq ($(BR2_PACKAGE_LIBFOO),y)
+57: TARGETS+=libfoo
+58: endif
 
    
 
-    
    First of all, this Makefile example works for a package which comprises a single
-    binary executable. For other software, such as libraries or more
-    complex stuff with multiple binaries, it must be adapted. For examples look at
-    the other *.mk files in the package
-    directory. 
    
+    
    First of all, this Makefile example works for a package which 
+    comprises a single binary executable. For other software, such as 
+    libraries or more complex stuff with multiple binaries, it must be 
+    adapted. For examples look at the other *.mk files in the 
+    package directory.
    
 
     
    At lines 6-11, a couple of useful variables are
     defined:
    
 
     
      
+      
    • LIBFOO_VERSION: The version of libfoo that 
+      should be downloaded.
      • 
 
-     
    • FOO_VERSION: The version of foo that
-     should be downloaded. 
      • 
+      
    • LIBFOO_SOURCE: The name of the tarball of libfoo 
+      on the download website or FTP site. As you can see 
+      LIBFOO_VERSION is used.
      • 
 
-     
    • FOO_SOURCE: The name of the tarball of
-     foo on the download website or FTP site. As you can see
-     FOO_VERSION is used. 
      • 
+      
    • LIBFOO_SITE: The HTTP or FTP site from which 
+      libfoo archive is downloaded. It must include the complete path to 
+      the directory where LIBFOO_SOURCE can be found.
      • 
 
-     
    • FOO_SITE: The HTTP or FTP site from which
-     foo archive is downloaded. It must include the complete
-     path to the directory where FOO_SOURCE can be
-     found. 
      • 
+      
    • LIBFOO_DIR: The directory into which the software will 
+      be configured and compiled. Basically, it's a subdirectory of 
+      BUILD_DIR which is created upon decompression of the tarball.
+      
      • 
 
-     
    • FOO_DIR: The directory into which the software
-     will be configured and compiled. Basically, it's a subdirectory
-     of BUILD_DIR which is created upon decompression of
-     the tarball. 
      • 
+      
    • LIBFOO_BINARY: Software binary name. As said previously, 
+      this is an example for a package with a single binary.
      • 
+
+      
    • LIBFOO_TARGET_BINARY: The full path of the binary inside 
+      the target filesystem.
      •  
    
+
+    
    Lines 13-14 define a target that downloads 
+    the tarball from the remote site to the download directory 
+    (DL_DIR).
    
+
+    
    Lines 16-18 define a target and associated 
+    rules that uncompress the downloaded tarball. As you can see, this 
+    target depends on the tarball file so that the previous target (lines 13-14) is called before executing the rules of the 
+    current target. Uncompressing is followed by touching a hidden 
+    file to mark the software as having been uncompressed. This trick is 
+    used everywhere in a Buildroot Makefile to split steps (download, 
+    uncompress, configure, compile, install) while still having correct 
+    dependencies.
    
+
+    
    Lines 20-31 define a target and associated 
+    rules that configure the software. It depends on the previous target 
+    (the hidden .source file) so that we are sure the software 
+    has been uncompressed. In order to configure the package, it basically 
+    runs the well-known ./configure script. As we may be doing 
+    cross-compilation, target, host and 
+    build arguments are given. The prefix is also set to 
+    /usr, not because the software will be installed in 
+    /usr on your host system, but because the software will bin 
+    installed in  /usr on the target filesystem. Finally it 
+    creates a .configured file to mark the software as 
+    configured.
    
+
+    
    Lines 33-34 define a target and a rule that 
+    compile the software. This target will create the binary file in the 
+    compilation directory and depends on the software being already 
+    configured (hence the reference to the .configured file). 
+    It basically runs make inside the source directory.
    
+
+    
    Lines 36-38 define a target and associated 
+    rules that install the software inside the target filesystem. They 
+    depend on the binary file in the source directory to make sure the 
+    software has been compiled. They use the install-strip 
+    target of the software Makefile by passing a 
+    DESTDIR argument so that the Makefile doesn't 
+    try to install the software in the host /usr but rather in 
+    the target /usr. After the installation, the 
+    /usr/man  directory inside the target filesystem is removed 
+    to save space. 
    
+
+    
    Line 40 defines the main target of the 
+    software — the one that will be eventually be used by the top level 
+    Makefile to download, compile, and then install this 
+    package. This target should first of all depend on all needed 
+    dependencies of the software (in our example, uclibc and 
+    ncurses) and also depend on the final binary. This last dependency 
+    will call all previous dependencies in the correct order.
    
+
+    
    Line 42 defines a simple target that only 
+    downloads the code source. This is not used during normal operation of 
+    Buildroot, but is needed if you intend to download all required sources 
+    at once for later offline build. Note that if you add a new package 
+    providing a libfoo-source target is mandatory to 
+    support users that wish to do offline-builds. Furthermore it eases 
+    checking if all package-sources are downloadable.
    
+
+    
    Lines 44-46 define a simple target to clean 
+    the software build by calling the Makefiles with the appropriate option. 
+    The -clean target should run make clean on 
+    $(BUILD_DIR)/package-version and MUST uninstall all files of the package 
+    from $(STAGING_DIR) and from $(TARGET_DIR).
    
+
+    
    Lines 48-49 define a simple target to 
+    completely remove the directory in which the software was uncompressed, 
+    configured and compiled. The -dirclean target MUST 
+    completely rm $(BUILD_DIR)/ package-version.
    
+
+    
    Lines 51-58 add the target libfoo 
+    to the list of targets to be compiled by Buildroot by first checking if 
+    the configuration option for this package has been enabled using the 
+    configuration tool. If so, it then "subscribes" this package 
+    to be compiled by adding the package to the TARGETS global variable.  
+    The name added to the TARGETS global variable is the name of this 
+    package's target, as defined on line 40, which 
+    is used by Buildroot to download, compile, and then install this package.
+    
    
 
-     
  • FOO_BINARY: Software binary name. As said
-     previously, this is an example for a package with a single binary.
    • 
+    
    Gettext integration and interaction with packages
    
 
-     
  • FOO_TARGET_BINARY: The full path of the binary
-     inside the target filesystem. 
    • 
+    
    Many packages that support internationalization use the gettext 
+    library. Dependency on this library are fairly complicated and therefore 
+    deserves a few explanations.
    
 
-    

+    
The uClibc C library doesn't implement gettext functionality, 
+    therefore with this C library, a separate gettext must be compiled. On 
+    the other hand, the glibc C library does integrate its own 
+    gettext, and in this case, the separate gettext library should not be 
+    compiled, because it creates various kind of build failures.

 
-    
Lines 13-14 define a target that downloads the
-    tarball from the remote site to the download directory
-    (DL_DIR). 

-
-    
Lines 16-18 define a target and associated rules
-    that uncompress the downloaded tarball. As you can see, this target
-    depends on the tarball file so that the previous target (lines
-    13-14) is called before executing the rules of the
-    current target. Uncompressing is followed by touching a hidden file
-    to mark the software as having been uncompressed. This trick is
-    used everywhere in a Buildroot Makefile to split steps
-    (download, uncompress, configure, compile, install) while still
-    having correct dependencies. 

-
-    
Lines 20-31 define a target and associated rules
-    that configure the software. It depends on the previous target (the
-    hidden .source file) so that we are sure the software has
-    been uncompressed. In order to configure the package, it basically runs the
-    well-known ./configure script. As we may be doing
-    cross-compilation, target, host and
-    build arguments are given. The prefix is also set to
-    /usr, not because the software will be installed in
-    /usr on your host system, but because the software will
-    bin installed in /usr on the target
-    filesystem. Finally it creates a .configured file to
-    mark the software as configured. 

-
-    
Lines 33-34 define a target and a rule that
-    compile the software. This target will create the binary file in the
-    compilation directory and depends on the software being already
-    configured (hence the reference to the .configured
-    file). It basically runs make inside the source
-    directory. 

-
-    
Lines 36-38 define a target and associated rules
-    that install the software inside the target filesystem. They depend on the
-    binary file in the source directory to make sure the software has
-    been compiled. They use the install-strip target of the
-    software Makefile by passing a DESTDIR
-    argument so that the Makefile doesn't try to install
-    the software in the host /usr but rather in the target
-    /usr. After the installation, the
-    /usr/man directory inside the target filesystem is
-    removed to save space. 

-
-    
Line 40 defines the main target of the software —
-    the one that will be eventually be used by the top level
-    Makefile to download, compile, and then install
-    this package. This target should first of all depend on all
-    needed dependencies of the software (in our example,
-    uclibc and ncurses) and also depend on the
-    final binary. This last dependency will call all previous
-    dependencies in the correct order. 

-
-    
Line 42 defines a simple target that only
-    downloads the code source. This is not used during normal operation of
-    Buildroot, but is needed if you intend to download all required sources at
-    once for later offline build. Note that if you add a new package providing
-    a foo-source target is mandatory to support
-    users that wish to do offline-builds. Furthermore it eases checking
-    if all package-sources are downloadable. 

-
-    
Lines 44-46 define a simple target to clean the
-    software build by calling the Makefiles with the appropriate option.
-    The -clean target should run make clean
-    on $(BUILD_DIR)/package-version and MUST uninstall all files of the
-    package from $(STAGING_DIR) and from $(TARGET_DIR). 

-
-    
Lines 48-49 define a simple target to completely
-    remove the directory in which the software was uncompressed, configured and
-    compiled. The -dirclean target MUST completely rm $(BUILD_DIR)/
-    package-version. 

-
-    
Lines 51-58 add the target foo to
-    the list of targets to be compiled by Buildroot by first checking if
-    the configuration option for this package has been enabled
-    using the configuration tool. If so, it then "subscribes"
-    this package to be compiled by adding the package to the TARGETS
-    global variable.  The name added to the TARGETS global
-    variable is the name of this package's target, as defined on
-    line 40, which is used by Buildroot to download,
-    compile, and then install this package. 

-
-    
Gettext integration and
-    interaction with packages

-
-    
Many packages that support internationalization use the gettext
-    library. Dependency on this library are fairly complicated and
-    therefore deserves a few explanations.

-
-    
The uClibc C library doesn't implement gettext
-    functionality, therefore with this C library, a separate gettext
-    must be compiled. On the other hand, the glibc C library
-    does integrate its own gettext, and in this case, the separate
-    gettext library should not be compiled, because it creates various
-    kind of build failures.

-
-    
Additionally, some packages (such as libglib2) do require
-    gettext unconditionally, while other packages (those who
-    support --disable-nls in general) only require
-    gettext when locale support is enabled.

+    
Additionally, some packages (such as libglib2) do require gettext 
+    unconditionally, while other packages (those who support 
+    --disable-nls in general) only require gettext when locale 
+    support is enabled.

 
     
Therefore, Buildroot defines two configuration options:

 
@@ -1576,64 +1517,52 @@ LIBFOO_POST_PATCH_HOOKS += LIBFOO_POST_PATCH_FIXUP
       
  • BR2_NEEDS_GETTEXT, which is true as soon as the
       toolchain doesn't provide its own gettext implementation
    • 
 
-      
  • BR2_NEEDS_GETTEXT_IF_LOCALE, which is true if
-      the toolchain doesn't provide its own gettext implementation and
-      if locale support is enabled
    • 
-
-    
+      
  • BR2_NEEDS_GETTEXT_IF_LOCALE, which is true if the 
+      toolchain doesn't provide its own gettext implementation and if locale 
+      support is enabled
    •  
 
     
    Therefore, packages that unconditionally need gettext should:
    
 
     
      
-      
    1. Use select BR2_PACKAGE_GETTEXT if
-      BR2_NEEDS_GETTEXT and possibly select
-      BR2_PACKAGE_LIBINTL if BR2_NEEDS_GETTEXT if libintl is
-      also needed
      2. 
+      
    2. Use select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT 
+      and possibly select BR2_PACKAGE_LIBINTL if BR2_NEEDS_GETTEXT 
+      if libintl is also needed
      3. 
 
-      
    3. Use $(if $(BR2_NEEDS_GETTEXT),gettext) in the
-      package DEPENDENCIES variable
      4. 
+      
    4. Use $(if $(BR2_NEEDS_GETTEXT),gettext) in the package 
+      DEPENDENCIES variable
      5. 
     
    
 
-    
    Packages that need gettext only when locale support is enabled
-    should:
    
+    
    Packages that need gettext only when locale support is enabled should:
+    
    
 
     
      
-      
    1. Use select BR2_PACKAGE_GETTEXT if
-      BR2_NEEDS_GETTEXT_IF_LOCALE and possibly select
-      BR2_PACKAGE_LIBINTL if BR2_NEEDS_GETTEXT_IF_LOCALE if
-      libintl is also needed
      2. 
-
-      
    2. Use $(if
-      $(BR2_NEEDS_GETTEXT_IF_LOCALE),gettext) in the
-      package DEPENDENCIES variable
      3. 
+      
    3. Use 
+      select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT_IF_LOCALE 
+      and possibly 
+      select BR2_PACKAGE_LIBINTL if BR2_NEEDS_GETTEXT_IF_LOCALE 
+      if libintl is also needed
      4. 
+
+      
    4. Use $(if $(BR2_NEEDS_GETTEXT_IF_LOCALE),gettext) in 
+      the package DEPENDENCIES variable
      5. 
     
    
 
     
    Conclusion
    
 
-    
    As you can see, adding a software package to Buildroot is simply a
-    matter of writing a Makefile using an  existing
-    example and modifying it according to the compilation process required by
-    the package. 
    
+    
    As you can see, adding a software package to Buildroot is simply a 
+    matter of writing a Makefile using an  existing example and modifying it 
+    according to the compilation process required by the package.
    
 
-    
    If you package software that might be useful for other people,
-    don't forget to send a patch to Buildroot developers!
    
+    
    If you package software that might be useful for other people, don't 
+    forget to send a patch to Buildroot developers!
    
 
-     
    Resources
    
+    
 
-    
    To learn more about Buildroot you can visit these
-    websites:
    
+    
    To learn more about Buildroot you can visit these websites:
    
 
     
   
-
-
 
 
-- 
2.30.2