#
# Copyright (c) 2011, 2024, Oracle and/or its affiliates. All rights reserved.
# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
#
# This code is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 only, as
# published by the Free Software Foundation.  Oracle designates this
# particular file as subject to the "Classpath" exception as provided
# by Oracle in the LICENSE file that accompanied this code.
#
# This code is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# version 2 for more details (a copy is included in the LICENSE file that
# accompanied this code).
#
# You should have received a copy of the GNU General Public License version
# 2 along with this work; if not, write to the Free Software Foundation,
# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
#
# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
# or visit www.oracle.com if you need additional information or have any
# questions.
#

################################################################################
# This file contains functionality related to handling paths for source files
# and object files. This is complicated by the fact that we usually, but not
# always, use absolute instead of relative paths. It is further complicated
# by the fact that not all tools allow inputting large lists of files as
# "@-files", which we normally use to avoid hitting command line length limits.
# Finally this file contains functionality for locating all source code files
# that should be included in the compilation.

################################################################################
# When absolute paths are not allowed in the output, and the compiler does not
# support any options to avoid it, we need to rewrite compile commands to use
# relative paths. By doing this, the __FILE__ macro will resolve to relative
# paths. The relevant input paths on the command line are the -I flags and the
# path to the source file itself.
#
# The macro MakeCommandRelative is used to rewrite the command line like this:
# 'CD $(WORKSPACE_ROOT) && <cmd>'
# and changes all paths in cmd to be relative to the workspace root. This only
# works properly if the build dir is inside the workspace root. If it's not,
# relative paths are still calculated, but depending on the distance between the
# dirs, paths in the build dir may end up as essentially absolute anyway.
#
# The fix-deps-file macro is used to adjust the contents of the generated make
# dependency files to contain paths compatible with make.
#
REWRITE_PATHS_RELATIVE = false
ifeq ($(ALLOW_ABSOLUTE_PATHS_IN_OUTPUT)-$(FILE_MACRO_CFLAGS), false-)
  REWRITE_PATHS_RELATIVE = true
endif

# CCACHE_BASEDIR needs fix-deps-file as makefiles use absolute filenames for
# object files while CCACHE_BASEDIR will make ccache relativize all paths for
# its compiler. The compiler then produces relative dependency files.
# make does not know a relative and absolute filename is the same so it will
# ignore such dependencies. This only applies when the OUTPUTDIR is inside
# the WORKSPACE_ROOT.
ifneq ($(CCACHE), )
  ifneq ($(filter $(WORKSPACE_ROOT)/%, $(OUTPUTDIR)), )
    REWRITE_PATHS_RELATIVE = true
  endif
endif

ifeq ($(REWRITE_PATHS_RELATIVE), true)
  # Need to handle -I flags as both '-Ifoo' and '-I foo'.
  MakeCommandRelative = \
      $(CD) $(WORKSPACE_ROOT) && \
      $(foreach o, $1, \
        $(if $(filter $(WORKSPACE_ROOT)/% $(OUTPUTDIR)/%, $o), \
          $(call RelativePath, $o, $(WORKSPACE_ROOT)) \
        , \
          $(if $(filter -I$(WORKSPACE_ROOT)/%, $o), \
            -I$(call RelativePath, $(patsubst -I%, %, $o), $(WORKSPACE_ROOT)) \
          , \
            $o \
          ) \
        ) \
      )

  # When compiling with relative paths, the deps file may come out with relative
  # paths, and that path may start with './'. First remove any leading ./, then
  # add WORKSPACE_ROOT to any line not starting with /, while allowing for
  # leading spaces. There may also be multiple entries on the same line, so start
  # with splitting such lines.
  # Non GNU sed (BSD on macosx) cannot substitute in literal \n using regex.
  # Instead use a bash escaped literal newline. To avoid having unmatched quotes
  # ruin the ability for an editor to properly syntax highlight this file, define
  # that newline sequence as a separate variable and add the closing quote behind
  # a comment.
  sed_newline := \'$$'\n''#'
  define fix-deps-file
	$(SED) \
	    -e 's|\([^ ]\) \{1,\}\([^\\:]\)|\1 \\$(sed_newline) \2|g' \
	    $1.tmp \
	    | $(SED) \
	        -e 's|^\([ ]*\)\./|\1|' \
	        -e '/^[ ]*[^/ ]/s|^\([ ]*\)|\1$(WORKSPACE_ROOT)/|' \
	        > $1
  endef
else
  # By default the MakeCommandRelative macro does nothing.
  MakeCommandRelative = $1

  # No adjustment is needed.
  define fix-deps-file
	$(MV) $1.tmp $1
  endef
endif

################################################################################
define SetupSourceFiles
  $$(foreach d, $$($1_SRC), $$(if $$(wildcard $$d), , \
      $$(error SRC specified to SetupNativeCompilation $1 contains missing directory $$d)))

  $1_SRCS_RAW := $$(call FindFiles, $$($1_SRC))
  # Order src files according to the order of the src dirs
  $1_SRCS := $$(foreach d, $$($1_SRC), $$(filter $$d%, $$($1_SRCS_RAW)))
  $1_SRCS := $$(filter $$(NATIVE_SOURCE_EXTENSIONS), $$($1_SRCS))
  # Extract the C/C++ files.
  ifneq ($$($1_EXCLUDE_PATTERNS), )
    # We must not match the exclude pattern against the src root(s).
    $1_SRCS_WITHOUT_ROOTS := $$($1_SRCS)
    $$(foreach i, $$($1_SRC), $$(eval $1_SRCS_WITHOUT_ROOTS := $$(patsubst \
        $$i/%,%, $$($1_SRCS_WITHOUT_ROOTS))))
    $1_ALL_EXCLUDE_FILES :=  $$(call containing, $$($1_EXCLUDE_PATTERNS), \
        $$($1_SRCS_WITHOUT_ROOTS))
  endif
  ifneq ($$($1_EXCLUDE_FILES), )
    $1_ALL_EXCLUDE_FILES += $$($1_EXCLUDE_FILES)
  endif
  ifneq ($$($1_ALL_EXCLUDE_FILES), )
    $1_EXCLUDE_FILES_PAT := $$($1_ALL_EXCLUDE_FILES) \
        $$(foreach i, $$($1_SRC), $$(addprefix $$i/, $$($1_ALL_EXCLUDE_FILES)))
    $1_EXCLUDE_FILES_PAT := $$(addprefix %, $$($1_EXCLUDE_FILES_PAT))
    $1_SRCS := $$(filter-out $$($1_EXCLUDE_FILES_PAT), $$($1_SRCS))
  endif
  ifneq ($$($1_INCLUDE_FILES), )
    $1_INCLUDE_FILES_PAT := $$(foreach i, $$($1_SRC), $$(addprefix $$i/, $$($1_INCLUDE_FILES)))
    $1_SRCS := $$(filter $$($1_INCLUDE_FILES_PAT), $$($1_SRCS))
  endif
  # Now we have a list of all c/c++ files to compile: $$($1_SRCS)

  # Prepend the source/bin path to the filter expressions. Then do the filtering.
  ifneq ($$($1_INCLUDES), )
    $1_SRC_INCLUDES := $$(foreach i, $$($1_SRC), $$(addprefix $$i/, $$(addsuffix /%, $$($1_INCLUDES))))
    $1_SRCS := $$(filter $$($1_SRC_INCLUDES), $$($1_SRCS))
  endif
  ifneq ($$($1_EXCLUDES), )
    $1_SRC_EXCLUDES := $$(addsuffix /%, $$($1_EXCLUDES))
    $1_SRC_EXCLUDES += $$(foreach i, $$($1_SRC), $$(addprefix $$i/, $$(addsuffix /%, $$($1_EXCLUDES))))
    $1_SRCS := $$(filter-out $$($1_SRC_EXCLUDES), $$($1_SRCS))
  endif

  $1_SRCS += $$($1_EXTRA_FILES)

  ifeq ($$($1_SRCS), )
    $$(error No sources found for $1 when looking inside the dirs $$($1_SRC))
  endif

  ifeq ($$($1_TYPE), EXECUTABLE)
    ifeq ($(UBSAN_ENABLED), true)
      # We need to set the default options for UBSan. This needs to be included in every executable.
      # Rather than copy and paste code to everything with a main function, we add an additional
      # source file to every executable that exports __ubsan_default_options.
      ifneq ($$(filter %.cpp %.cc, $$($1_SRCS)), )
        $1_SRCS += $(TOPDIR)/make/data/ubsan/ubsan_default_options.cpp
      else
        $1_SRCS += $(TOPDIR)/make/data/ubsan/ubsan_default_options.c
      endif
    endif
  endif
endef

################################################################################
define SetupOutputFiles
  # Calculate the expected output from compiling the sources
  $1_EXPECTED_OBJS_FILENAMES := $$(call replace_with_obj_extension, $$(notdir $$($1_SRCS)))
  $1_EXPECTED_OBJS := $$(addprefix $$($1_OBJECT_DIR)/, $$($1_EXPECTED_OBJS_FILENAMES))
  # Sort to remove duplicates and provide a reproducible order on the input files to the linker.
  $1_ALL_OBJS := $$(sort $$($1_EXPECTED_OBJS) $$($1_EXTRA_OBJECT_FILES))
  ifeq ($(STATIC_LIBS), true)
    # Exclude the object files that match with $1_STATIC_LIB_EXCLUDE_OBJS.
    ifneq ($$($1_STATIC_LIB_EXCLUDE_OBJS), )
      $1_ALL_OBJS := $$(call not-containing, $$($1_STATIC_LIB_EXCLUDE_OBJS), $$($1_ALL_OBJS))
    endif
  endif
endef

################################################################################
define RemoveSuperfluousOutputFiles
  # Are there too many object files on disk? Perhaps because some source file was removed?
  $1_BINS := $$(wildcard $$($1_OBJECT_DIR)/*$(OBJ_SUFFIX))
  $1_SUPERFLOUS_OBJS := $$(sort $$(filter-out $$($1_EXPECTED_OBJS), $$($1_BINS)))
  # Clean out the superfluous object files.
  ifneq ($$($1_SUPERFLUOUS_OBJS), )
    $$(shell $(RM) -f $$($1_SUPERFLUOUS_OBJS))
  endif
endef

################################################################################
define SetupObjectFileList
  $1_LD_OBJ_ARG := $$($1_ALL_OBJS)

  # If there are many object files, use an @-file...
  ifneq ($$(word 17, $$($1_ALL_OBJS)), )
    $1_OBJ_FILE_LIST := $$($1_OBJECT_DIR)/_$1_objectfilenames.txt
    $1_LD_OBJ_ARG := @$$($1_OBJ_FILE_LIST)

    # If we are building static library, 'AR' on macosx/aix may not support @-file.
    ifeq ($$($1_TYPE), STATIC_LIBRARY)
      ifeq ($(call isTargetOs, macosx aix), true)
        $1_LD_OBJ_ARG := `cat $$($1_OBJ_FILE_LIST)`
      endif
    endif
  endif

  # Unfortunately the @-file trick does not work reliably when using clang.
  # Clang does not propagate the @-file parameter to the ld sub process, but
  # instead puts the full content on the command line. At least the llvm ld
  # does not even support an @-file.
  #
  # When linking a large amount of object files, we risk hitting the limit
  # of the command line length even on posix systems if the path length of
  # the output dir is very long due to our use of absolute paths. To
  # mitigate this, use paths relative to the output dir when linking over
  # 500 files with clang and the output dir path is deep.
  ifneq ($$(word 500, $$($1_ALL_OBJS)), )
    ifeq ($$(TOOLCHAIN_TYPE), clang)
      # There is no strlen function in make, but checking path depth is a
      # reasonable approximation.
      ifneq ($$(word 10, $$(subst /, ,$$(OUTPUTDIR))), )
        $1_LINK_OBJS_RELATIVE := true
        $1_ALL_OBJS_RELATIVE := $$(patsubst $$(OUTPUTDIR)/%, %, $$($1_ALL_OBJS))
      endif
    endif
  endif
endef