75 lines
2.0 KiB
Lua
75 lines
2.0 KiB
Lua
|
---------
|
||
|
|
-- Utility functions for operations on a file system.
|
||
|
|
--
|
||
|
|
-- **Note: This module is not part of public API!**
|
||
|
|
----
|
||
|
|
local fmt = string.format
|
||
|
|
local open = io.open
|
||
|
|
|
||
|
|
local UTF8_BOM = '\239\187\191'
|
||
|
|
|
||
|
|
local function normalize_io_error (name, err)
|
||
|
|
if err:sub(1, #name + 2) == name..': ' then
|
||
|
|
err = err:sub(#name + 3)
|
||
|
|
end
|
||
|
|
return err
|
||
|
|
end
|
||
|
|
|
||
|
|
local M = {}
|
||
|
|
|
||
|
|
--- Reads the specified file and returns its content as string.
|
||
|
|
--
|
||
|
|
-- @tparam string filename Path of the file to read.
|
||
|
|
-- @tparam string mode The mode in which to open the file, see @{io.open} (default: "r").
|
||
|
|
-- @treturn[1] string A content of the file.
|
||
|
|
-- @treturn[2] nil
|
||
|
|
-- @treturn[2] string An error message.
|
||
|
|
function M.read_file (filename, mode)
|
||
|
|
local handler, err = open(filename, mode or 'r')
|
||
|
|
if not handler then
|
||
|
|
return nil, fmt('Could not open %s for reading: %s',
|
||
|
|
filename, normalize_io_error(filename, err))
|
||
|
|
end
|
||
|
|
|
||
|
|
local content, err = handler:read('*a') --luacheck: ignore 411
|
||
|
|
if not content then
|
||
|
|
return nil, fmt('Could not read %s: %s', filename, normalize_io_error(filename, err))
|
||
|
|
end
|
||
|
|
|
||
|
|
handler:close()
|
||
|
|
|
||
|
|
if content:sub(1, #UTF8_BOM) == UTF8_BOM then
|
||
|
|
content = content:sub(#UTF8_BOM + 1)
|
||
|
|
end
|
||
|
|
|
||
|
|
return content
|
||
|
|
end
|
||
|
|
|
||
|
|
--- Writes the given data to the specified file.
|
||
|
|
--
|
||
|
|
-- @tparam string filename Path of the file to write.
|
||
|
|
-- @tparam string data The data to write.
|
||
|
|
-- @tparam ?string mode The mode in which to open the file, see @{io.open} (default: "w").
|
||
|
|
-- @treturn[1] true
|
||
|
|
-- @treturn[2] nil
|
||
|
|
-- @treturn[2] string An error message.
|
||
|
|
function M.write_file (filename, data, mode)
|
||
|
|
local handler, err = open(filename, mode or 'w')
|
||
|
|
if not handler then
|
||
|
|
return nil, fmt('Could not open %s for writing: %s',
|
||
|
|
filename, normalize_io_error(filename, err))
|
||
|
|
end
|
||
|
|
|
||
|
|
local _, err = handler:write(data) --luacheck: ignore 411
|
||
|
|
if err then
|
||
|
|
return nil, fmt('Could not write %s: %s', filename, normalize_io_error(filename, err))
|
||
|
|
end
|
||
|
|
|
||
|
|
handler:flush()
|
||
|
|
handler:close()
|
||
|
|
|
||
|
|
return true
|
||
|
|
end
|
||
|
|
|
||
|
|
return M
|