use more native Lua code instead of os.execute

Suggested-by: Matěj Cepl <mcepl@cepl.eu>

1 files changed, 11 insertions, 7 deletions

diff --git a/init.lua b/init.lua
index ff38679..8b8a8c6 100644
--- a/init.lua
+++ b/init.lua
@@ -75,18 +75,19 @@ end
 
 local created_locks = {}
 local function create_lock_file(lfile_path)
-  local already_locked = os.execute('test -e ' .. '"' .. lfile_path .. '"')
-  if already_locked then
+  local lock_file = io.open(lfile_path)
+  if lock_file then
+    lock_file:close()
     return false
   end
 
   -- create the lock file with our pid
-  local cmd = 'echo ' .. vis_pid .. ' > "' .. lfile_path .. '"'
-  assert(os.execute(cmd))
+  lock_file = assert(io.open(lfile_path, 'w'))
+  lock_file:write(vis_pid)
+  lock_file:close()
 
   -- detect a possible race
-  local lock_file = io.open(lfile_path)
-  assert(lock_file)
+  lock_file = assert(io.open(lfile_path))
   local lock_pid = lock_file:read('*n')
   lock_file:close()
   local locked = tonumber(lock_pid) == vis_pid
@@ -100,7 +101,10 @@ local function create_lock_file(lfile_path)
 end
 
 local function delete_lock_file(lfile_path)
-  os.execute('rm ' .. '"' .. lfile_path .. '"')
+  local success, err = os.remove(lfile_path)
+  if not success then
+    vis:info('vis-lockfiles: ' .. err)
+  end
   created_locks[lfile_path] = nil
 end