[syslinux:master] lua: enable dynamic module loading

[syslinux-bot for Ferenc Wágner]

Commit-ID:  351ce48b5a009eb9f3a3a6a21051351a2f0b381b
Gitweb:     http://www.syslinux.org/commit/351ce48b5a009eb9f3a3a6a21051351a2f0b381b
Author:     Ferenc Wágner <wferi at niif.hu>
AuthorDate: Sun, 13 Oct 2013 21:52:53 +0200
Committer:  Ferenc Wágner <wferi at niif.hu>
CommitDate: Sat, 1 Mar 2014 17:40:34 +0100

lua: enable dynamic module loading


---
 com32/lua/src/loadlib.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 com32/lua/src/luaconf.h |  3 +++
 2 files changed, 48 insertions(+)

diff --git a/com32/lua/src/loadlib.c b/com32/lua/src/loadlib.c
index a995927..3962889 100644
--- a/com32/lua/src/loadlib.c
+++ b/com32/lua/src/loadlib.c
@@ -212,6 +212,51 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 /* }====================================================== */
 
 
+#elif defined(SYSLINUX)
+/*
+** {=========================================================================
+** This is an implementation of loadlib for the Syslinux COM32 module system.
+** ==========================================================================
+*/
+
+#include <sys/module.h>
+
+static void ll_unloadlib (void *lib) {
+  module_unload ((struct elf_module *)lib);
+}
+
+
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  int err;
+  struct elf_module *lib = module_alloc (path);
+  if (lib == NULL) {
+    lua_pushstring (L, "module not found");
+    return NULL;
+  }
+  (void)seeglb; /* gcc, ignore it */
+  err = module_load (lib);
+  if (err) {
+    printf ("module load error: %d\n", err);
+    lua_pushstring (L, "failed to load module");
+    return NULL;
+  }
+  return (void *)lib;
+}
+
+
+static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
+  Elf_Sym *p = module_find_symbol (sym, (struct elf_module *)lib);
+  if (p == NULL) {
+    lua_pushstring (L, "symbol not found in module");
+    return NULL;
+  }
+  return (lua_CFunction)module_get_absolute(p->st_value, (struct elf_module *)lib);
+}
+
+/* }====================================================== */
+
+
+
 #else
 /*
 ** {======================================================
diff --git a/com32/lua/src/luaconf.h b/com32/lua/src/luaconf.h
index fa6546b..7fd4eaa 100644
--- a/com32/lua/src/luaconf.h
+++ b/com32/lua/src/luaconf.h
@@ -97,6 +97,9 @@
 #define LUA_CPATH_DEFAULT \
 		LUA_CDIR"?.dll;" LUA_CDIR"loadall.dll;" ".\\?.dll"
 
+#elif defined(SYSLINUX)
+#define LUA_PATH_DEFAULT  "./?.lua"
+#define LUA_CPATH_DEFAULT "./?.c32"
 #else			/* }{ */
 
 #define LUA_VDIR	LUA_VERSION_MAJOR "." LUA_VERSION_MINOR "/"