syscnf: fix root_dir path to be absolute

We do change directory and it makes sense to use absolute path either
way so let's go for it.

src/lib/autoload/a_06_syscnf.lua

@@ -17,7 +17,9 @@ You should have received a copy of the GNU General Public License
 along with Updater.  If not, see <http://www.gnu.org/licenses/>.
 ]]--
 
+local os = os
 local utils = require "utils"
+local getcwd = getcwd
 local DIE = DIE
 
 module "syscnf"
@@ -27,10 +29,26 @@ module "syscnf"
 -- Functions that we want to access from outside of this module
 -- luacheck: globals set_root_dir set_target
 
-local status_file_suffix = "/usr/lib/opkg/status"
-local info_dir_suffix = "/usr/lib/opkg/info/"
-local pkg_temp_dir_suffix = "/usr/share/updater/unpacked"
-local dir_opkg_collided_suffix = "/usr/share/updater/collided"
+local status_file_suffix = "usr/lib/opkg/status"
+local info_dir_suffix = "usr/lib/opkg/info/"
+local pkg_temp_dir_suffix = "usr/share/updater/unpacked/"
+local dir_opkg_collided_suffix = "usr/share/updater/collided/"
+
+--[[
+Canonizes path to absolute path. It does no change in case path is already an
+absolute but it if not then it prepends current working directory. There is also
+special handling in case path starts with tilde (~) in that case that character is
+replaced with content of HOME environment variable.
+]]
+local function path2abspath(path)
+	if path:match("^/") then
+		return path
+	elseif path:match("^~/") then
+		return os.getenv('HOME') .. "/" .. path
+	else
+		return getcwd() .. "/" .. path
+	end
+end
 
 --[[
 Set all the configurable directories to be inside the provided dir
@@ -38,11 +56,14 @@ Effectively sets that the whole system is mounted under some
 prefix.
 ]]
 function set_root_dir(dir)
-	-- A root directory
-	root_dir = dir or "/"
-
-	dir = dir or ""
+	if dir then
+		dir = (path2abspath(dir) .. "/"):gsub("/+", "/")
+	else
+		dir = "/"
+	end
 
+	-- A root directory
+	root_dir = dir
 	-- The file with status of installed packages
 	status_file = dir .. status_file_suffix
 	-- The directory where unpacked control files of the packages live

src/lib/autoload/a_08_backend.lua

@@ -936,7 +936,7 @@ end
 function pkg_config_info(f, configs)
 	-- Make sure there are no // in there, which would confuse the directory cleaning code
 	f = f:gsub("/+", "/")
-	local path = syscnf.root_dir .. f
+	local path = syscnf.root_dir .. f:gsub("^/+", "")
 	local hash = configs[f]
 	return path, hash and config_modified(path, hash)
 end
@@ -1013,6 +1013,7 @@ function script_run(pkg_name, script_name, ...)
 			s_ecode = ecode
 			s_stderr = stderr
 		end, function ()
+			-- If root is / then variable is empty otherwise absolute path is used
 			local dir = syscnf.root_dir:gsub('^/+$', '')
 			setenv("PKG_ROOT", dir)
 			setenv("IPKG_INSTROOT", dir)
@@ -1182,7 +1183,7 @@ function run_state_cache:init()
 	assert(not self.status)
 	-- TODO: Make it configurable? OpenWRT hardcodes this into the binary, but we may want to be usable on non-OpenWRT systems as well.
 	local ok, err = pcall(function()
-		self.lfile = locks.acquire(syscnf.root_dir .. "/var/lock/opkg.lock")
+		self.lfile = locks.acquire(syscnf.root_dir .. "var/lock/opkg.lock")
 		self.status = status_parse()
 		self.initialized = true
 	end)

src/lib/autoload/a_09_transaction.lua

@@ -287,7 +287,7 @@ local function perform_internal(operations, journal_status, run_state)
 	local ok, err = pcall(function ()
 		-- Make sure the temporary directory for unpacked packages exist
 		local created = ""
-		for segment in (syscnf.pkg_temp_dir .. "/"):gmatch("([^/]*)/") do
+		for segment in syscnf.pkg_temp_dir:gmatch("([^/]*)/") do
 			created = created .. segment .. "/"
 			backend.dir_ensure(created)
 		end

tests/syscnf.lua

@@ -23,10 +23,11 @@ local SC = require "syscnf"
 module("syscnf-tests", package.seeall, lunit.testcase)
 
 function test_set_root_dir()
-	SC.set_root_dir("/dir")
+	SC.set_root_dir("/dir/")
 	assert_equal("/dir/usr/lib/opkg/status", SC.status_file)
 	assert_equal("/dir/usr/lib/opkg/info/", SC.info_dir)
-	assert_equal("/dir/usr/share/updater/unpacked", SC.pkg_temp_dir)
+	assert_equal("/dir/usr/share/updater/unpacked/", SC.pkg_temp_dir)
+	assert_equal("/dir/usr/share/updater/collided/", SC.dir_opkg_collided)
 end
 
 function test_set_target()

tests/system/Makefile.dir

@@ -23,6 +23,7 @@ UPD_SYS_TESTS := \
 	list-dir \
 	force-downgrade \
 	conflicts \
+	postinst \
 	reboot-recover-update
 
 .PHONY: test-sys valgrind-sys check

tests/system/postinst/cleanup

+sed -i -e 's/^Installed-Time: .*/Installed-Time: 0/' "$ROOT_DIR"/usr/lib/opkg/status
+rm "$ROOT_DIR"/config
+rm -r "$ROOT_DIR"/repo
+for file in "$ROOT_DIR"/usr/lib/opkg/info/*.list; do
+	LC_ALL=C sort -d -o "$file".out "$file"
+	mv -f "$file".out "$file"
+done

tests/system/postinst/input/config

+Repository("test", "file://%ROOT_DIR%/repo")
+Install("test-package")

tests/system/postinst/output/postinst.txt

+Postinst file

tests/system/postinst/output/test-file

+Just some file

tests/system/postinst/output/usr/lib/opkg/info/test-package.control

+Package: test-package
+Version: 1
+License: GPL-2.0
+Section: none
+Architecture: all
+Installed-Size: 0
+Description:  Simple test package with postinst script
+

tests/system/postinst/output/usr/lib/opkg/info/test-package.files-md5sum

+d8f086fc5f75be4200fa6a8753119844  /test-file

tests/system/postinst/output/usr/lib/opkg/info/test-package.list

+/test-file

tests/system/postinst/output/usr/lib/opkg/info/test-package.postinst

+#!/bin/sh
+# We should have have root in our root and IPKG_INSTROOT should contain path to it
+[ -f "${IPKG_INSTROOT}usr/lib/opkg/status" ] || exit 1
+echo "Postinst file" > "${IPKG_INSTROOT}/postinst.txt"

tests/system/postinst/output/usr/lib/opkg/status

+Package: test-package
+Version: 1
+Status: install user installed
+Architecture: all
+Installed-Time: 0
+

tests/system/postinst/params

+file://$ROOT_DIR/config --batch -R "$ROOT_DIR"

tests/system/postinst/setup

+sed -i -e "s#%ROOT_DIR%#$ROOT_DIR#" $ROOT_DIR/config