wslua: fix source argument in debug info for luacov

The source argument should start with a '@', otherwise it is treated as
actual source code instead of a filename. This is needed for luacov. See
https://www.lua.org/manual/5.2/manual.html#lua_Debug
https://github.com/keplerproject/luacov/issues/55

Change-Id: I0a3e2da65fb6b4aaabb9173a07fdea18a788f3e3
Reviewed-on: https://code.wireshark.org/review/29447
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 15 insertions, 13 deletions

diff --git a/epan/wslua/init_wslua.c b/epan/wslua/init_wslua.c
index caf05626cf..302aa82571 100644
--- a/epan/wslua/init_wslua.c
+++ b/epan/wslua/init_wslua.c
@@ -524,11 +524,13 @@ static gboolean lua_load_script(const gchar* filename, const gchar* dirname, con
     lua_settop(L,0);
 
     lua_pushcfunction(L,lua_main_error_handler);
+    /* The source argument should start with with '@' to indicate a file. */
+    lua_pushfstring(L, "@%s", filename);
 
 #if LUA_VERSION_NUM >= 502
-    error = lua_load(L,getF,file,filename,NULL);
+    error = lua_load(L, getF, file, lua_tostring(L, -1), NULL);
 #else
-    error = lua_load(L,getF,file,filename);
+    error = lua_load(L, getF, file, lua_tostring(L, -1));
 #endif
 
     switch (error) {
@@ -540,23 +542,23 @@ static gboolean lua_load_script(const gchar* filename, const gchar* dirname, con
                 numargs = lua_script_push_args(file_count);
             }
             error = lua_pcall(L,numargs,0,1);
-            fclose(file);
-            lua_pop(L,1); /* pop the error handler */
-            return error ? FALSE : TRUE;
-        case LUA_ERRSYNTAX: {
+            break;
+
+        case LUA_ERRSYNTAX:
             report_failure("Lua: syntax error during precompilation of `%s':\n%s",filename,lua_tostring(L,-1));
-            fclose(file);
-            return FALSE;
-        }
+            break;
+
         case LUA_ERRMEM:
             report_failure("Lua: memory allocation error during precompilation of %s",filename);
-            fclose(file);
-            return FALSE;
+            break;
+
         default:
             report_failure("Lua: unknown error during precompilation of %s: %d",filename,error);
-            fclose(file);
-            return FALSE;
+            break;
     }
+    fclose(file);
+    lua_pop(L, 2);  /* pop the filename and error handler */
+    return error == 0;
 }
 
 /* This one is used to load the init.lua scripts, or anything else