1 files changed, 50 insertions, 0 deletions
diff --git a/src/luarocks/fs/linux.lua b/src/luarocks/fs/linux.lua
new file mode 100644
index 0000000..c1b057c
--- /dev/null
+++ b/src/luarocks/fs/linux.lua
@@ -0,0 +1,50 @@
+--- Linux-specific implementation of filesystem and platform abstractions.
+local linux = {}
+
+local fs = require("luarocks.fs")
+local dir = require("luarocks.dir")
+
+function linux.is_dir(file)
+   file = fs.absolute_name(file)
+   file = dir.normalize(file) .. "/."
+   local fd, _, code = io.open(file, "r")
+   if code == 2 then -- "No such file or directory"
+      return false
+   end
+   if code == 20 then -- "Not a directory", regardless of permissions
+      return false
+   end
+   if code == 13 then -- "Permission denied", but is a directory
+      return true
+   end
+   if fd then
+      local _, _, ecode = fd:read(1)
+      fd:close()
+      if ecode == 21 then -- "Is a directory"
+         return true
+      end
+   end
+   return false
+end
+
+function linux.is_file(file)
+   file = fs.absolute_name(file)
+   if fs.is_dir(file) then
+      return false
+   end
+   file = dir.normalize(file)
+   local fd, _, code = io.open(file, "r")
+   if code == 2 then -- "No such file or directory"
+      return false
+   end
+   if code == 13 then -- "Permission denied", but it exists
+      return true
+   end
+   if fd then
+      fd:close()
+      return true
+   end
+   return false
+end
+
+return linux