build: introduce $(MKHASH)

Before this commit, it was assumed that mkhash is in the PATH. While
this was fine for the normal build workflow, this led to some issues if

    make TOPDIR="$(pwd)" -C "$pkgdir" compile

was called manually. In most of the cases, I just saw warnings like this:

    make: Entering directory '/home/.../package/gluon-status-page'
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    bash: line 1: mkhash: command not found
    [...]

While these were only warnings and the package still compiled sucessfully,
I also observed that some package even fail to build because of this.

After applying this commit, the variable $(MKHASH) is introduced. This
variable points to $(STAGING_DIR_HOST)/bin/mkhash, which is always the
correct path.

Signed-off-by: Leonardo Mörlein <me@irrelefant.net>

include/depends.mk

@@ -11,7 +11,7 @@
 
 DEP_FINDPARAMS := -x "*/.svn*" -x ".*" -x "*:*" -x "*\!*" -x "* *" -x "*\\\#*" -x "*/.*_check" -x "*/.*.swp" -x "*/.pkgdir*"
 
-find_md5=find $(wildcard $(1)) -type f $(patsubst -x,-and -not -path,$(DEP_FINDPARAMS) $(2)) -printf "%p%T@\n" | sort | mkhash md5
+find_md5=find $(wildcard $(1)) -type f $(patsubst -x,-and -not -path,$(DEP_FINDPARAMS) $(2)) -printf "%p%T@\n" | sort | $(MKHASH) md5
 
 define rdep
   .PRECIOUS: $(2)

include/download.mk

@@ -74,7 +74,7 @@ else
   check_warn = $(if $(filter-out undefined,$(origin F_$(1))),$(filter ,$(shell $(call F_$(1),$(2),$(3),$(4)) >&2)),$(check_warn_nofix))
 endif
 
-gen_sha256sum = $(shell mkhash sha256 $(DL_DIR)/$(1))
+gen_sha256sum = $(shell $(MKHASH) sha256 $(DL_DIR)/$(1))
 
 ifdef FIXUP
 F_hash_deprecated = $(SCRIPT_DIR)/fixup-makefile.pl $(CURDIR)/Makefile fix-hash $(3) $(call gen_sha256sum,$(1)) $(2)

include/image-commands.mk

@@ -198,7 +198,7 @@ define Build/elx-header
 			dd bs=20 count=1 conv=sync; \
 		echo -ne "$$(printf '%08x' $$(stat -c%s $@) | fold -s2 | xargs -I {} echo \\x{} | tr -d '\n')" | \
 			dd bs=8 count=1 conv=sync; \
-		echo -ne "$$($(STAGING_DIR_HOST)/bin/mkhash md5 $@ | fold -s2 | xargs -I {} echo \\x{} | tr -d '\n')" | \
+		echo -ne "$$($(MKHASH) md5 $@ | fold -s2 | xargs -I {} echo \\x{} | tr -d '\n')" | \
 			dd bs=58 count=1 conv=sync; \
 	) > $(KDIR)/tmp/$(DEVICE_NAME).header
 	$(call Build/xor-image,-p $(xor_pattern) -x)

include/image.mk

@@ -26,7 +26,7 @@ param_get_default = $(firstword $(call param_get,$(1),$(2)) $(3))
 param_mangle = $(subst $(space),_,$(strip $(1)))
 param_unmangle = $(subst _,$(space),$(1))
 
-mkfs_packages_id = $(shell echo $(sort $(1)) | mkhash md5 | cut -b1-8)
+mkfs_packages_id = $(shell echo $(sort $(1)) | $(MKHASH) md5 | cut -b1-8)
 mkfs_target_dir = $(if $(call param_get,pkg,$(1)),$(KDIR)/target-dir-$(call param_get,pkg,$(1)),$(TARGET_DIR))
 
 KDIR=$(KERNEL_BUILD_DIR)
@@ -40,8 +40,8 @@ IMG_PREFIX_VERCODE:=$(if $(CONFIG_VERSION_CODE_FILENAMES),$(call sanitize,$(VERS
 IMG_PREFIX:=$(VERSION_DIST_SANITIZED)-$(IMG_PREFIX_VERNUM)$(IMG_PREFIX_VERCODE)$(IMG_PREFIX_EXTRA)$(BOARD)$(if $(SUBTARGET),-$(SUBTARGET))
 IMG_ROOTFS:=$(IMG_PREFIX)-rootfs
 IMG_COMBINED:=$(IMG_PREFIX)-combined
-IMG_PART_SIGNATURE:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | mkhash md5 | cut -b1-8)
-IMG_PART_DISKGUID:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | mkhash md5 | sed -E 's/(.{8})(.{4})(.{4})(.{4})(.{10})../\1-\2-\3-\4-\500/')
+IMG_PART_SIGNATURE:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | $(MKHASH) md5 | cut -b1-8)
+IMG_PART_DISKGUID:=$(shell echo $(SOURCE_DATE_EPOCH)$(LINUX_VERMAGIC) | $(MKHASH) md5 | sed -E 's/(.{8})(.{4})(.{4})(.{4})(.{10})../\1-\2-\3-\4-\500/')
 
 MKFS_DEVTABLE_OPT := -D $(INCLUDE_DIR)/device_table.txt
 

include/kernel-defaults.mk

@@ -116,7 +116,7 @@ define Kernel/Configure/Default
 		cp $(LINUX_DIR)/.config.set $(LINUX_DIR)/.config.prev; \
 	}
 	$(_SINGLE) [ -d $(LINUX_DIR)/user_headers ] || $(KERNEL_MAKE) INSTALL_HDR_PATH=$(LINUX_DIR)/user_headers headers_install
-	grep '=[ym]' $(LINUX_DIR)/.config.set | LC_ALL=C sort | mkhash md5 > $(LINUX_DIR)/.vermagic
+	grep '=[ym]' $(LINUX_DIR)/.config.set | LC_ALL=C sort | $(MKHASH) md5 > $(LINUX_DIR)/.vermagic
 endef
 
 define Kernel/Configure/Initramfs
@@ -186,5 +186,3 @@ define Kernel/Clean/Default
 	rm -f $(LINUX_KERNEL)
 	$(_SINGLE)$(MAKE) -C $(KERNEL_BUILD_DIR)/linux-$(LINUX_VERSION) clean
 endef
-
-

include/package-ipkg.mk

@@ -221,7 +221,7 @@ $(_endef)
     ifneq ($$(CONFIG_IPK_FILES_CHECKSUMS),)
 	(cd $$(IDIR_$(1)); \
 		( \
-			find . -type f \! -path ./CONTROL/\* -exec mkhash sha256 -n \{\} \; 2> /dev/null | \
+			find . -type f \! -path ./CONTROL/\* -exec $(MKHASH) sha256 -n \{\} \; 2> /dev/null | \
 			sed 's|\([[:blank:]]\)\./| \1/|' > $$(IDIR_$(1))/CONTROL/files-sha256sum \
 		) || true \
 	)

include/quilt.mk

@@ -159,7 +159,7 @@ define Quilt/Template
 		false; \
 	}
 	@[ -n "$$$$(ls $(1)/patches/series)" -o \
-	   "$$$$(cat $(1)/patches/series | mkhash md5)" = "$$(sort $(1)/patches/series | mkhash md5)" ] || { \
+	   "$$$$(cat $(1)/patches/series | $(MKHASH) md5)" = "$$(sort $(1)/patches/series | $(MKHASH) md5)" ] || { \
 		echo "The patches are not sorted in the right order. Please fix."; \
 		false; \
 	}

include/scan.mk

@@ -1,4 +1,5 @@
 include $(TOPDIR)/include/verbose.mk
+include $(TOPDIR)/rules.mk
 TMP_DIR:=$(TOPDIR)/tmp
 
 all: $(TMP_DIR)/.$(SCAN_TARGET)
@@ -100,7 +101,7 @@ $(TMP_DIR)/info/.files-$(SCAN_TARGET).mk: $(FILELIST)
 $(TARGET_STAMP)::
 	+( \
 		$(NO_TRACE_MAKE) $(FILELIST); \
-		MD5SUM=$$(cat $(FILELIST) $(OVERRIDELIST) | mkhash md5 | awk '{print $$1}'); \
+		MD5SUM=$$(cat $(FILELIST) $(OVERRIDELIST) | $(MKHASH) md5 | awk '{print $$1}'); \
 		[ -f "$@.$$MD5SUM" ] || { \
 			rm -f $@.*; \
 			touch $@.$$MD5SUM; \