From: Siavash Tavakoli <siavash.tavakoli@open-xchange.com>
Date: Thu, 12 Aug 2021 18:40:22 +0000 (+0100)
Subject: lib-lua: Add lua_resume_compat() and use it in lua versions prior to 5.4
X-Git-Tag: 2.3.17~197
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=72a864b4b041e3a4c597a5eeafe3bdc50ffa6dd5;p=thirdparty%2Fdovecot%2Fcore.git

lib-lua: Add lua_resume_compat() and use it in lua versions prior to 5.4

Starting lua 5.4 "lua_resume()" expects an extra "nresults" argument. Add a
compatibility function to handle this argument in earlier versions.
---

diff --git a/src/lib-lua/dlua-compat.c b/src/lib-lua/dlua-compat.c
index 19b43df430..94f27bac4b 100644
--- a/src/lib-lua/dlua-compat.c
+++ b/src/lib-lua/dlua-compat.c
@@ -146,3 +146,12 @@ lua_Integer lua_tointegerx(lua_State *L, int idx, int *isnum_r)
 	return 0;
 }
 #endif
+
+#if LUA_VERSION_NUM < 504
+#  undef lua_resume
+int lua_resume_compat(lua_State *L, lua_State *from, int nargs, int *nresults)
+{
+	*nresults = 1;
+	return lua_resume(L, from, nargs);
+}
+#endif
diff --git a/src/lib-lua/dlua-compat.h b/src/lib-lua/dlua-compat.h
index 6204429c85..307ae467b8 100644
--- a/src/lib-lua/dlua-compat.h
+++ b/src/lib-lua/dlua-compat.h
@@ -56,4 +56,14 @@ void lua_seti(lua_State *L, int index, lua_Integer n);
 lua_Integer lua_tointegerx(lua_State *L, int idx, int *isnum_r);
 #endif
 
+#if LUA_VERSION_NUM < 504
+/*
+ * lua_resume() compatibility function. Lua 5.4 expects an extra "nresults"
+ * argeument.
+ */
+#  define lua_resume(L, from, nargs, nresults) \
+	lua_resume_compat(L, from, nargs, nresults)
+int lua_resume_compat(lua_State *L, lua_State *from, int nargs, int *nresults);
+#endif
+
 #endif
diff --git a/src/lib-lua/dlua-resume.c b/src/lib-lua/dlua-resume.c
index 1e792558a4..ac46f1026e 100644
--- a/src/lib-lua/dlua-resume.c
+++ b/src/lib-lua/dlua-resume.c
@@ -106,7 +106,7 @@ static void queue_resume_callback(lua_State *L, int status)
 static void dlua_pcall_yieldable_continue(lua_State *L)
 {
 	struct timeout *to;
-	int nargs;
+	int nargs, nresults;
 	int ret;
 
 	nargs = dlua_tls_get_int(L, RESUME_NARGS);
@@ -117,7 +117,7 @@ static void dlua_pcall_yieldable_continue(lua_State *L)
 	dlua_tls_clear(L, RESUME_TIMEOUT);
 	dlua_tls_clear(L, RESUME_NARGS);
 
-	ret = lua_resume(L, L, nargs);
+	ret = lua_resume(L, L, nargs, &nresults);
 	if (ret == LUA_YIELD) {
 		/*
 		 * thread yielded - nothing to do
@@ -157,6 +157,7 @@ int dlua_pcall_yieldable(lua_State *L, const char *func_name, int nargs,
 {
 	struct dlua_pcall_resume_state *state;
 	int ret;
+	int nresults;
 
 	i_assert(lua_status(L) == LUA_OK);
 
@@ -180,7 +181,7 @@ int dlua_pcall_yieldable(lua_State *L, const char *func_name, int nargs,
 	lua_insert(L, -(nargs + 1));
 
 	/* stack: func, args (top) */
-	ret = lua_resume(L, L, nargs);
+	ret = lua_resume(L, L, nargs, &nresults);
 	if (ret == LUA_YIELD) {
 		/*
 		 * thread yielded - nothing to do