luatz/tzfile: Open files in readonly binary mode; and if invalid: throw a better...

diff --git a/luatz/tzfile.lua b/luatz/tzfile.lua
index eed426e75efc475af1d43ff3e2c81adf80f1ea57..96686dcac793d0be8a834513ea0676dad250228b 100644 (file)
--- a/luatz/tzfile.lua
+++ b/luatz/tzfile.lua
@@ -39,7 +39,7 @@ end
 
 local fifteen_nulls = ("\0"):rep(15)
 local function read_tz ( fd )
-       assert ( fd:read(4) == "TZif" )
+       assert ( fd:read(4) == "TZif" , "Invalid TZ file" )
        local version = assert ( fd:read(1) )
        if version == "\0" or version == "2" then
                local MIN_TIME = -2^32+1
@@ -198,7 +198,7 @@ local function read_tz ( fd )
 end
 
 local function read_tzfile ( path )
-       local fd = assert ( io.open ( path ) )
+       local fd = assert ( io.open ( path , "rb" ) )
        local tzinfo = read_tz ( fd )
        fd:close ( )
        return tzinfo