p/liberty
1
1
Fork 0
Code Issues Pull Requests Releases Activity

wdye: clean up protected calls

Browse Source 
Have a common way of catching Lua errors for resource cleanup purposes.
This commit is contained in:
Přemysl Eric Janouch 2025-01-15 02:20:45 +01:00
parent 0f20cce9c8
commit 9a26284a64
Signed by: p
GPG Key ID: A0420B94F92B9493
1 changed files with 14 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
tools/wdye/wdye.c
View File

@ -890,10 +890,11 @@ environ_map_serialize (struct str_map *env, struct strv *envv)
static int
spawn_protected (lua_State *L)
{
struct spawn_context *ctx = lua_touserdata (L, 1);
struct spawn_context *ctx = lua_touserdata (L, lua_upvalueindex (1));
luaL_checktype (L, 1, LUA_TTABLE);
// Step 1: Prepare process environment.
if (xlua_getfield (L, 2, "environ", LUA_TTABLE, true))
if (xlua_getfield (L, 1, "environ", LUA_TTABLE, true))
{
environ_map_update (&ctx->env, L);
lua_pop (L, 1);
@ -913,11 +914,11 @@ spawn_protected (lua_State *L)
#endif
// Step 3: Prepare process command line.
size_t argc = lua_rawlen (L, 2);
size_t argc = lua_rawlen (L, 1);
for (size_t i = 1; i <= argc; i++)
{
lua_pushinteger (L, i);
lua_rawget (L, 2);
lua_rawget (L, 1);
const char *arg = lua_tostring (L, -1);
if (!arg)
return luaL_error (L, "spawn arguments must be strings");
@ -1004,23 +1005,24 @@ spawn_protected (lua_State *L)
static int
xlua_spawn (lua_State *L)
{
luaL_checktype (L, 1, LUA_TTABLE);
lua_pushcfunction (L, xlua_error_handler);
lua_pushcfunction (L, spawn_protected);
lua_insert (L, 1);
struct spawn_context ctx = {};
lua_pushlightuserdata (L, &ctx);
lua_pushcclosure (L, spawn_protected, 1);
lua_insert (L, 2);
// There are way too many opportunities for Lua to throw,
// so maintain a context to clean up in one go.
struct spawn_context ctx = spawn_context_make ();
lua_pushlightuserdata (L, &ctx);
lua_rotate (L, 1, -1);
int result = lua_pcall (L, 2, 1, -4);
ctx = spawn_context_make ();
int result = lua_pcall (L, lua_gettop (L) - 2, 1, 1);
spawn_context_free (&ctx);
if (result)
return lua_error (L);
// Remove the error handler ("good programming practice").
lua_remove (L, -2);
lua_remove (L, 1);
return 1;
}