support/scripts/mkmakefile

   1 #!/bin/sh
   2 # Generates a small Makefile used in the root of the output
   3 # directory, to allow make to be started from there.
   4 # The Makefile also allow for more convenient build of external modules
   5
   6 # Usage
   7 # $1 - Kernel src directory
   8 # $2 - Output directory
   9
  10
  11 test ! -r $2/Makefile -o -O $2/Makefile || exit 0
  12 # Only overwrite automatically generated Makefiles
  13 # (so we do not overwrite buildroot Makefile)
  14 if test -e $2/Makefile && ! grep -q Automatically $2/Makefile
  15 then
  16         exit 0
  17 fi
  18 echo "  GEN     $2/Makefile"
  19
  20 cat << EOF > $2/Makefile
  21 # Automatically generated by $0: don't edit
  22
  23 lastword = \$(word \$(words \$(1)),\$(1))
  24 makedir := \$(dir \$(call lastword,\$(MAKEFILE_LIST)))
  25
  26 MAKEARGS := -C $1
  27 MAKEARGS += O=\$(if \$(patsubst /%,,\$(makedir)),\$(CURDIR)/)\$(patsubst %/,%,\$(makedir))
  28
  29 MAKEFLAGS += --no-print-directory
  30
  31 .PHONY: _all \$(MAKECMDGOALS)
  32
  33 all     := \$(filter-out Makefile,\$(MAKECMDGOALS))
  34
  35 _all:
  36         umask 0022 && \$(MAKE) \$(MAKEARGS) \$(all)
  37
  38 Makefile:;
  39
  40 \$(all): _all
  41         @:
  42
  43 %/: _all
  44         @:
  45 EOF