How to add my own software to a Buildroot Linux package?

Question

I am trying to add my own program to a small linux, created with Buildroot. What I\'ve done so far:

• I\'ve created a new directory inside my \'buildroot/package/

Answer 1

Minimal tested example on top of 2016.05

GitHub upstream: https://github.com/cirosantilli/buildroot/tree/in-tree-package-2016.05

This example adds the package source in-tree, which is simple for educational purposes and the way to go if you want to merge back (kudos!),

If you do not intend on merging back (booooh!), it is more likely that you will want to use Buildroot as a git submodule and either:

• an out of tree package with BR2_EXTERNAL as shown at: https://github.com/cirosantilli/buildroot/tree/out-of-tree-2016.05
• *_OVERRIDE_SRCDIR + other git submodules as explained at: How to modify the source of Buildroot packages for package development?

Files modified:

package/Config.in

menu "Misc"
    source "package/hello/Config.in"
endmenu

package/hello/Config.in

config BR2_PACKAGE_HELLO
    bool "hello"
    help
        Hello world package.

        http://example.com

package/hello/hello.mk

################################################################################
#
# hello
#
################################################################################

HELLO_VERSION = 1.0
HELLO_SITE = ./package/hello/src
HELLO_SITE_METHOD = local

define HELLO_BUILD_CMDS
    $(MAKE) CC="$(TARGET_CC)" LD="$(TARGET_LD)" -C $(@D)
endef

define HELLO_INSTALL_TARGET_CMDS
    $(INSTALL) -D -m 0755 $(@D)/hello $(TARGET_DIR)/usr/bin
endef

$(eval $(generic-package))

package/hello/src/.gitignore

hello

package/hello/src/Makefile

CC = gcc

.PHONY: clean

hello: hello.c
    $(CC) -o '$@' '$<'

clean:
    rm hello

package/hello/src/hello.c

#include 

int main(void) {
    puts("hello");
}

Usage:

make qemu_x86_64_defconfig
echo 'BR2_PACKAGE_HELLO=y' >> .config
make BR2_JLEVEL=2
qemu-system-x86_64 -M pc -kernel output/images/bzImage -drive file=output/images/rootfs.ext2,if=virtio,format=raw -append root=/dev/vda -net nic,model=virtio -net user

From inside qemu:

hello

Expected output:

hello

Tested in Ubuntu 16.04.