scripts/mkmakefile

   1 #!/bin/sh
   2 # SPDX-License-Identifier: GPL-2.0
   3 # Generates a small Makefile used in the root of the output
   4 # directory, to allow make to be started from there.
   5 # The Makefile also allow for more convinient build of external modules
   6
   7 # Usage
   8 # $1 - Kernel src directory
   9 # $2 - Output directory
  10 # $3 - version
  11 # $4 - patchlevel
  12
  13
  14 test ! -r $2/Makefile -o -O $2/Makefile || exit 0
  15 # Only overwrite automatically generated Makefiles
  16 # (so we do not overwrite kernel Makefile)
  17 if test -e $2/Makefile && ! grep -q Automatically $2/Makefile
  18 then
  19         exit 0
  20 fi
  21 if [ "${quiet}" != "silent_" ]; then
  22         echo "  GEN     $2/Makefile"
  23 fi
  24
  25 cat << EOF > $2/Makefile
  26 # Automatically generated by $0: don't edit
  27
  28 VERSION = $3
  29 PATCHLEVEL = $4
  30
  31 lastword = \$(word \$(words \$(1)),\$(1))
  32 makedir := \$(dir \$(call lastword,\$(MAKEFILE_LIST)))
  33
  34 ifeq ("\$(origin V)", "command line")
  35 VERBOSE := \$(V)
  36 endif
  37 ifneq (\$(VERBOSE),1)
  38 Q := @
  39 endif
  40
  41 MAKEARGS := -C $1
  42 MAKEARGS += O=\$(if \$(patsubst /%,,\$(makedir)),\$(CURDIR)/)\$(patsubst %/,%,\$(makedir))
  43
  44 MAKEFLAGS += --no-print-directory
  45
  46 .PHONY: __sub-make \$(MAKECMDGOALS)
  47
  48 __sub-make:
  49         \$(Q)\$(MAKE) \$(MAKEARGS) \$(MAKECMDGOALS)
  50
  51 \$(filter-out __sub-make, \$(MAKECMDGOALS)): __sub-make
  52         @:
  53 EOF