useradd.bbclass: use locking of bb.utils to avoid lock race issue of useradd/groupadd

index bb8f42b..ed5ed69 100644
@@ -14,126 +14,90 @@ USERADDDEPENDS_virtclass-nativesdk = ""
 # c) As the preinst script in the target package at do_rootfs time
 # d) As the preinst script in the target package on device as a package upgrade
 #
-useradd_preinst () {
-OPT=""
-SYSROOT=""
-
-if test "x$D" != "x"; then
-	# Installing into a sysroot
-	SYSROOT="$D"
-	OPT="--root $D"
-
-	# Add groups and users defined for all recipe packages
-	GROUPADD_PARAM="${@get_all_cmd_params(d, 'group')}"
-	USERADD_PARAM="${@get_all_cmd_params(d, 'user')}"
-else
-	# Installing onto a target
-	# Add groups and users defined only for this package
-	GROUPADD_PARAM="${GROUPADD_PARAM}"
-	USERADD_PARAM="${USERADD_PARAM}"
-fi
-
-# Perform group additions first, since user additions may depend
-# on these groups existing
-if test "x$GROUPADD_PARAM" != "x"; then
-	echo "Running groupadd commands..."
-	# Invoke multiple instances of groupadd for parameter lists
-	# separated by ';'
-	opts=`echo "$GROUPADD_PARAM" | cut -d ';' -f 1`
-	remaining=`echo "$GROUPADD_PARAM" | cut -d ';' -f 2-`
-	while test "x$opts" != "x"; do
-		groupname=`echo "$opts" | awk '{ print $NF }'`
-		group_exists=`grep "^$groupname:" $SYSROOT/etc/group || true`
-		if test "x$group_exists" = "x"; then
-			count=1
-			while true; do
-				eval $PSEUDO groupadd $OPT $opts || true
-				group_exists=`grep "^$groupname:" $SYSROOT/etc/group || true`
-				if test "x$group_exists" = "x"; then
-					# File locking issues can require us to retry the command
-					echo "WARNING: groupadd command did not succeed. Retrying..."
-					sleep 1
-				else
-					break
-				fi
-				count=`expr $count + 1`
-				if test $count = 11; then
-					echo "ERROR: tried running groupadd command 10 times without success, giving up"
-					exit 1
-				fi
-			done		
-		else
-			echo "Note: group $groupname already exists, not re-creating it"
-		fi
-
-		if test "x$opts" = "x$remaining"; then
-			break
-		fi
-		opts=`echo "$remaining" | cut -d ';' -f 1`
-		remaining=`echo "$remaining" | cut -d ';' -f 2-`
-	done
-fi 
-
-if test "x$USERADD_PARAM" != "x"; then
-	echo "Running useradd commands..."
-	# Invoke multiple instances of useradd for parameter lists
-	# separated by ';'
-	opts=`echo "$USERADD_PARAM" | cut -d ';' -f 1`
-	remaining=`echo "$USERADD_PARAM" | cut -d ';' -f 2-`
-	while test "x$opts" != "x"; do
-		# useradd does not have a -f option, so we have to check if the
-		# username already exists manually
-		username=`echo "$opts" | awk '{ print $NF }'`
-		user_exists=`grep "^$username:" $SYSROOT/etc/passwd || true`
-		if test "x$user_exists" = "x"; then
-			count=1
-			while true; do
-				eval $PSEUDO useradd $OPT $opts || true
-				user_exists=`grep "^$username:" $SYSROOT/etc/passwd || true`
-				if test "x$user_exists" = "x"; then
-					# File locking issues can require us to retry the command
-					echo "WARNING: useradd command did not succeed. Retrying..."
-					sleep 1
-				else
-					break
-				fi
-				count=`expr $count + 1`
-				if test $count = 11; then
-					echo "ERROR: tried running useradd command 10 times without success, giving up"
-					exit 1
-				fi
-			done
-		else
-			echo "Note: username $username already exists, not re-creating it"
-		fi
-
-		if test "x$opts" = "x$remaining"; then
-			break
-		fi
-		opts=`echo "$remaining" | cut -d ';' -f 1`
-		remaining=`echo "$remaining" | cut -d ';' -f 2-`
-	done
-fi
+def useradd_preinst(d):
+	import re
+
+	sysroot = ""
+	opt = ""
+
+	dir = d.getVar('STAGING_DIR_TARGET', True)
+	if dir:
+		# Installing into a sysroot
+		sysroot = dir
+		opt = "--root %s" % dir
+
+		# Add groups and users defined for all recipe packages
+		groupadd_param = get_all_cmd_params(d, 'group')
+		useradd_param = get_all_cmd_params(d, 'user')
+	else:
+		# Installing onto a target
+		# Add groups and users defined only for this package
+		groupadd_param = d.getVar('GROUPADD_PARAM', True)
+		useradd_param = d.getVar('GROUPADD_PARAM', True)
+
+	group_file = '%s/etc/group' % sysroot
+	user_file = '%s/etc/passwd' % sysroot
+
+	# Use the locking of bb to the group/passwd file to avoid the
+	# locking issue of groupadd/useradd
+	group_lock = '%s.locked' % group_file
+	user_lock = '%s.locked' % user_file
+	lockfiles = [group_lock, user_lock]
+
+	with bb.utils.fileslocked(lockfiles):
+		# Perform group additions first, since user additions may depend
+		# on these groups existing
+		if groupadd_param and sysroot:
+			bb.debug(1, "Running groupadd commands ...")
+			# Invoke multiple instances of groupadd for parameter lists
+			# separated by ';'
+			param_list = groupadd_param.split(';')
+			for opts in param_list:
+				groupname = opts.split()[-1]
+				with open(group_file, 'r') as f:
+					passwd_lines = f.read()
+				group_re = re.compile('\n%s' % groupname)
+				if group_re.search(passwd_lines):
+					bb.note("Note: groupname %s already exists, not re-creating it" % groupname)
+					continue
+				try:
+					output, err = bb.process.run('groupadd %s %s' % (opt, opts))
+				except bb.process.CmdError as exc:
+					bb.error("Failed to add group: %s" % exc)
+				else:
+					bb.note("Successful to add group %s" % groupname)
+
+		if useradd_param:
+			bb.debug(1, "Running useradd commands ...")
+			# Invoke multiple instances of useradd for parameter lists
+			# separated by ';'
+			param_list = useradd_param.split(';')
+			for opts in param_list:
+				# useradd does not have a -f option, so we have to check if the
+				# username already exists manually
+				username = opts.split()[-1]
+				with open(user_file, 'r') as f:
+					passwd_lines = f.read()
+				user_re = re.compile('\n%s' % username)
+				if user_re.search(passwd_lines):
+					bb.note("Note: username %s already exists, not re-creating it" % username)
+					continue
+				try:
+					output, err = bb.process.run('useradd %s %s' % (opt, opts))
+				except bb.process.CmdError as exc:
+					bb.error("Failed to add user: %s" % exc)
+				else:
+					bb.note("Successful to add user %s" % username)
+
+fakeroot python useradd_sysroot () {
+	useradd_preinst(d)
 }
 
-useradd_sysroot () {
-	# Pseudo may (do_install) or may not (do_populate_sysroot_setscene) be running 
-	# at this point so we're explicit about the environment so pseudo can load if 
-	# not already present.
-	export PSEUDO="${FAKEROOTENV} PSEUDO_LOCALSTATEDIR=${STAGING_DIR_TARGET}${localstatedir}/pseudo ${STAGING_DIR_NATIVE}${bindir}/pseudo"
-
-	# Explicitly set $D since it isn't set to anything
-	# before do_install
-	D=${STAGING_DIR_TARGET}
-	useradd_preinst
+fakeroot python useradd_sysroot_sstate () {
+    if d.getVar("BB_CURRENTTASK", True) == "package_setscene":
+        useradd_preinst(d)
 }
 
-useradd_sysroot_sstate () {
-	if [ "${BB_CURRENTTASK}" = "package_setscene" ]
-	then
-		useradd_sysroot
-	fi
-}
 
 do_install[prefuncs] += "${SYSROOTFUNC}"
 SYSROOTFUNC = "useradd_sysroot"

@@ -146,7 +110,7 @@ SYSROOTPOSTFUNC_virtclass-cross = ""
 SYSROOTPOSTFUNC_virtclass-native = ""
 SYSROOTPOSTFUNC_virtclass-nativesdk = ""
 
-USERADDSETSCENEDEPS = "${MLPREFIX}base-passwd:do_populate_sysroot_setscene shadow-native:do_populate_sysroot_setscene ${MLPREFIX}shadow-sysroot:do_populate_sysroot_setscene"
+USERADDSETSCENEDEPS = "base-passwd:do_populate_sysroot_setscene shadow-native:do_populate_sysroot_setscene ${MLPREFIX}shadow-sysroot:do_populate_sysroot_setscene"
 USERADDSETSCENEDEPS_virtclass-cross = ""
 USERADDSETSCENEDEPS_virtclass-native = ""
 USERADDSETSCENEDEPS_virtclass-nativesdk = ""

@@ -154,61 +118,61 @@ do_package_setscene[depends] = "${USERADDSETSCENEDEPS}"
 
 # Recipe parse-time sanity checks
 def update_useradd_after_parse(d):
-    useradd_packages = d.getVar('USERADD_PACKAGES', True)
+	useradd_packages = d.getVar('USERADD_PACKAGES', True)
 
-    if not useradd_packages:
-        raise bb.build.FuncFailed, "%s inherits useradd but doesn't set USERADD_PACKAGES" % d.getVar('FILE')
+	if not useradd_packages:
+		raise bb.build.FuncFailed, "%s inherits useradd but doesn't set USERADD_PACKAGES" % d.getVar('FILE')
 
-    for pkg in useradd_packages.split():
-        if not d.getVar('USERADD_PARAM_%s' % pkg, True) and not d.getVar('GROUPADD_PARAM_%s' % pkg, True):
-            raise bb.build.FuncFailed, "%s inherits useradd but doesn't set USERADD_PARAM or GROUPADD_PARAM for package %s" % (d.getVar('FILE'), pkg)
+	for pkg in useradd_packages.split():
+		if not d.getVar('USERADD_PARAM_%s' % pkg, True) and not d.getVar('GROUPADD_PARAM_%s' % pkg, True):
+			raise bb.build.FuncFailed, "%s inherits useradd but doesn't set USERADD_PARAM or GROUPADD_PARAM for package %s" % (d.getVar('FILE'), pkg)
 
 python __anonymous() {
-    update_useradd_after_parse(d)
+	update_useradd_after_parse(d)
 }
 
 # Return a single [GROUP|USER]ADD_PARAM formatted string which includes the
 # [group|user]add parameters for all USERADD_PACKAGES in this recipe
 def get_all_cmd_params(d, cmd_type):
-    import string
-    
-    param_type = cmd_type.upper() + "ADD_PARAM_%s"
-    params = []
+	import string
+	
+	param_type = cmd_type.upper() + "ADD_PARAM_%s"
+	params = []
 
-    useradd_packages = d.getVar('USERADD_PACKAGES', True) or ""
-    for pkg in useradd_packages.split():
-        param = d.getVar(param_type % pkg, True)
-        if param:
-            params.append(param)
+	useradd_packages = d.getVar('USERADD_PACKAGES', True) or ""
+	for pkg in useradd_packages.split():
+		param = d.getVar(param_type % pkg, True)
+		if param:
+			params.append(param)
 
-    return string.join(params, "; ")
+	return string.join(params, "; ")
 
 # Adds the preinst script into generated packages
 fakeroot python populate_packages_prepend () {
-    def update_useradd_package(pkg):
-        bb.debug(1, 'adding user/group calls to preinst for %s' % pkg)
-
-        """
-        useradd preinst is appended here because pkg_preinst may be
-        required to execute on the target. Not doing so may cause
-        useradd preinst to be invoked twice, causing unwanted warnings.
-        """
-        preinst = d.getVar('pkg_preinst_%s' % pkg, True) or d.getVar('pkg_preinst', True)
-        if not preinst:
-            preinst = '#!/bin/sh\n'
-        preinst += d.getVar('useradd_preinst', True)
-        d.setVar('pkg_preinst_%s' % pkg, preinst)
-
-        # RDEPENDS setup
-        rdepends = d.getVar("RDEPENDS_%s" % pkg, True) or ""
-        rdepends += ' ' + d.getVar('MLPREFIX') + 'base-passwd'
-        rdepends += ' ' + d.getVar('MLPREFIX') + 'shadow'
-        d.setVar("RDEPENDS_%s" % pkg, rdepends)
-
-    # Add the user/group preinstall scripts and RDEPENDS requirements
-    # to packages specified by USERADD_PACKAGES
-    if not bb.data.inherits_class('nativesdk', d):
-        useradd_packages = d.getVar('USERADD_PACKAGES', True) or ""
-        for pkg in useradd_packages.split():
-            update_useradd_package(pkg)
+	def update_useradd_package(pkg):
+		bb.debug(1, 'adding user/group calls to preinst for %s' % pkg)
+
+		"""
+		useradd preinst is appended here because pkg_preinst may be
+		required to execute on the target. Not doing so may cause
+		useradd preinst to be invoked twice, causing unwanted warnings.
+		"""
+		preinst = d.getVar('pkg_preinst_%s' % pkg, True) or d.getVar('pkg_preinst', True)
+		if not preinst:
+			preinst = '#!/bin/sh\n'
+		preinst += d.getVar('useradd_preinst', True)
+		d.setVar('pkg_preinst_%s' % pkg, preinst)
+
+		# RDEPENDS setup
+		rdepends = d.getVar("RDEPENDS_%s" % pkg, True) or ""
+		rdepends += ' ' + d.getVar('MLPREFIX') + 'base-passwd'
+		rdepends += ' ' + d.getVar('MLPREFIX') + 'shadow'
+		d.setVar("RDEPENDS_%s" % pkg, rdepends)
+
+	# Add the user/group preinstall scripts and RDEPENDS requirements
+	# to packages specified by USERADD_PACKAGES
+	if not bb.data.inherits_class('nativesdk', d):
+		useradd_packages = d.getVar('USERADD_PACKAGES', True) or ""
+		for pkg in useradd_packages.split():
+			update_useradd_package(pkg)
 }