Initial commit

sys/apis/fs/ramfs.lua

@@ -0,0 +1,153 @@
+local ramfs = { }
+
+function ramfs.mount(dir, nodeType)
+  if nodeType == 'directory' then
+    return {
+      nodes = { },
+      size = 0,
+    }
+  elseif nodeType == 'file' then
+    return {
+      size = 0,
+    }
+  end
+  error('ramfs syntax: [directory, file]')
+end
+
+function ramfs.delete(node, dir)
+  if node.mountPoint == dir then
+    fs.unmount(node.mountPoint)
+  end
+end
+
+function ramfs.exists(node, fn)
+  return node.mountPoint == fn
+end
+
+function ramfs.getSize(node)
+  return node.size
+end
+
+function ramfs.isReadOnly()
+  return false
+end
+
+function ramfs.makeDir(node, dir)
+  fs.mount(dir, 'ramfs', 'directory')
+end
+
+function ramfs.isDir(node)
+  return not not node.nodes
+end
+
+function ramfs.getDrive()
+  return 'ram'
+end
+
+function ramfs.list(node, dir, full)
+  if node.nodes and node.mountPoint == dir then
+    local files = { }
+    if full then
+      for f,n in pairs(node.nodes) do
+        table.insert(files, {
+          name = f,
+          isDir = fs.isDir(fs.combine(dir, f)),
+          size = fs.getSize(fs.combine(dir, f)),
+        })
+      end
+    else
+      for k,v in pairs(node.nodes) do
+        table.insert(files, k)
+      end
+    end
+    return files
+  end
+  error('Not a directory')
+end
+
+function ramfs.open(node, fn, fl)
+
+  if fl ~= 'r' and fl ~= 'w' and fl ~= 'rb' and fl ~= 'wb' then
+    error('Unsupported mode')
+  end
+
+  if fl == 'r' then
+    if node.mountPoint ~= fn then
+      return
+    end
+
+    local ctr = 0
+    local lines
+    return {
+      readLine = function()
+        if not lines then
+          lines = Util.split(node.contents)
+        end
+        ctr = ctr + 1
+        return lines[ctr]
+      end,
+      readAll = function()
+        return node.contents
+      end,
+      close = function()
+        lines = nil
+      end,
+    }
+  elseif fl == 'w' then
+    node = fs.mount(fn, 'ramfs', 'file')
+
+    local c = ''
+    return {
+      write = function(str)
+        c = c .. str
+      end,
+      writeLine = function(str)
+        c = c .. str .. '\n'
+      end,
+      flush = function()
+        node.contents = c
+        node.size = #c
+      end,
+      close = function()
+        node.contents = c
+        node.size = #c
+        c = nil
+      end,
+    }
+  elseif fl == 'rb' then
+    if node.mountPoint ~= fn or not node.contents then
+      return
+    end
+
+    local ctr = 0
+    return {
+      read = function()
+        ctr = ctr + 1
+        return node.contents[ctr]
+      end,
+      close = function()
+      end,
+    }
+
+  elseif fl == 'wb' then
+    node = fs.mount(fn, 'ramfs', 'file')
+
+    local c = { }
+    return {
+      write = function(b)
+        table.insert(c, b)
+      end,
+      flush = function()
+        node.contents = c
+        node.size = #c
+      end,
+      close = function()
+        node.contents = c
+        node.size = #c
+        c = nil
+      end,
+    }
+  end
+end
+
+return ramfs