[PATCH v3] zram-swap: explicitely use mkswap/swapon/swapoff from /sbin

[Rui Salvaterra]

The required BusyBox applets are enabled by default, so we can rely on them
being present in the system. This way, we make sure there are no conflicts with
less featured variants of these same applets which might also be present in the
system.

v3: Make sure the required applets are enabled at build time.

Fixes: 0bd7dfa3ed60588ec83a8f60f48b6991ebb16940

Signed-off-by: Rui Salvaterra <rsalvaterra at gmail.com>
---
 package/system/zram-swap/Makefile        |  2 +-
 package/system/zram-swap/files/zram.init | 18 +++++++++---------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/package/system/zram-swap/Makefile b/package/system/zram-swap/Makefile
index 4422c351ea..32b17ca7a3 100644
--- a/package/system/zram-swap/Makefile
+++ b/package/system/zram-swap/Makefile
@@ -17,7 +17,7 @@ include $(INCLUDE_DIR)/package.mk
 define Package/zram-swap
   SECTION:=utils
   CATEGORY:=Base system
-  DEPENDS:=+kmod-zram +!(BUSYBOX_CONFIG_MKSWAP&&BUSYBOX_CONFIG_SWAPON&&BUSYBOX_CONFIG_SWAPOFF):swap-utils
+  DEPENDS:=+kmod-zram + at BUSYBOX_CONFIG_MKSWAP + at BUSYBOX_CONFIG_SWAPON + at BUSYBOX_CONFIG_FEATURE_SWAPON_DISCARD + at BUSYBOX_CONFIG_FEATURE_SWAPON_PRI + at BUSYBOX_CONFIG_SWAPOFF
   TITLE:=ZRAM swap scripts
   PKGARCH:=all
 endef
diff --git a/package/system/zram-swap/files/zram.init b/package/system/zram-swap/files/zram.init
index a6126e578f..f31a87438c 100755
--- a/package/system/zram-swap/files/zram.init
+++ b/package/system/zram-swap/files/zram.init
@@ -35,18 +35,18 @@ zram_applicable()
 		return 1
 	}
 
-	which mkswap >/dev/null || {
-		logger -s -t zram_applicable -p daemon.err "[ERROR] 'mkswap' not installed"
+	[ -x /sbin/mkswap ] || {
+		logger -s -t zram_applicable -p daemon.err "[ERROR] 'BusyBox mkswap' not installed"
 		return 1
 	}
 
-	which swapon >/dev/null || {
-		logger -s -t zram_applicable -p daemon.err "[ERROR] 'swapon' not installed"
+	[ -x /sbin/swapon ] || {
+		logger -s -t zram_applicable -p daemon.err "[ERROR] 'BusyBox swapon' not installed"
 		return 1
 	}
 
-	which swapoff >/dev/null || {
-		logger -s -t zram_applicable -p daemon.err "[ERROR] 'swapoff' not installed"
+	[ -x /sbin/swapoff ] || {
+		logger -s -t zram_applicable -p daemon.err "[ERROR] 'BusyBox swapoff' not installed"
 		return 1
 	}
 }
@@ -181,8 +181,8 @@ start()
 	zram_comp_algo "$zram_dev"
 	zram_comp_streams "$zram_dev"
 	echo $(( $zram_size * 1024 * 1024 )) >"/sys/block/$( basename "$zram_dev" )/disksize"
-	mkswap "$zram_dev"
-	swapon -d $zram_priority "$zram_dev"
+	/sbin/mkswap "$zram_dev"
+	/sbin/swapon -d $zram_priority "$zram_dev"
 }
 
 stop()
@@ -191,7 +191,7 @@ stop()
 
 	for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
 		logger -s -t zram_stop -p daemon.debug "deactivate swap $zram_dev"
-		swapoff "$zram_dev" && zram_reset "$zram_dev" "claiming memory back"
+		/sbin/swapoff "$zram_dev" && zram_reset "$zram_dev" "claiming memory back"
 		local dev_index="$( echo $zram_dev | grep -o "[0-9]*$" )"
 		if [ $dev_index -ne 0 ]; then
 			logger -s -t zram_stop -p daemon.debug "removing zram $zram_dev"
-- 
2.27.0