Lua: properly implement require from pack

doc/PACKS.md

@@ -101,8 +101,11 @@ The following interfaces are provided:
 
 ### global ScriptHost
 
-* `bool :LoadScript(luafilename)`: load and execute a lua script
+* `bool :LoadScript(luafilename)`: load and execute a lua script from absolute filename inside pack
   * `require` can be used instead (since PopTracker 0.21.0)
+  * `require` behaves mostly like Lua require since 0.25.6
+    * `"foo.baz"` will try `/scripts/foo/baz.lua`, `/scripts/foo/baz/init.lua`, `/foo/baz.lua` and `/foo/baz/init.lua`
+  * `...` contains mod name for relative require since 0.25.6
 * `bool :AddMemoryWatch(name,addr,len,callback,interal)`: add a memory watch for auto-tracking, see [AUTOTRACKING.md](AUTOTRACKING.md)
 * `bool :RemoveMemoryWatch(name)`: remove memory watch by name, available since 0.11.0
 * `bool :AddWatchForCode(name,code,callback)`: callback(code) will be called whenever an item changed state that canProvide(code). Only available in PopTracker, since 0.11.0, will return a reference (name) to the watch since 0.18.2. Use "*" to trigger for all codes since 0.25.5.
@@ -135,6 +138,7 @@ a table representing an enum with the following constants: \
 ### other globals
 
 * `DEBUG` set to true to get more error or debug output
+* `require` function, see [ScriptHost:LoadScript](#global-scripthost)
 
 
 ### type LuaItem

src/core/scripthost.cpp

@@ -159,7 +159,7 @@ bool ScriptHost::LoadScript(const std::string& file)
         fprintf(stderr, "File not found!\n");
         return false;
     }
-    
+
     const char* buf = script.c_str();
     size_t len = script.length();
     if (len>=3 && memcmp(buf, "\xEF\xBB\xBF", 3) == 0) {
@@ -168,7 +168,14 @@ bool ScriptHost::LoadScript(const std::string& file)
         len -= 3;
     }
     if (luaL_loadbufferx(_L, buf, len, file.c_str(), "t") == LUA_OK) {
-        if (lua_pcall(_L, 0, 1, 0) == LUA_OK) {
+        std::string modname = file;
+        if (strncasecmp(modname.c_str(), "scripts/", 8) == 0)
+            modname = modname.substr(8);
+        if (modname.length() > 4 && strcasecmp(modname.c_str() + modname.length() - 4, ".lua") == 0)
+            modname = modname.substr(0, modname.length() - 4);
+        std::replace(modname.begin(), modname.end(), '/', '.');
+        lua_pushstring(_L, modname.c_str());
+        if (lua_pcall(_L, 1, 1, 0) == LUA_OK) {
             // if it was executed successfully, pop everything from stack
             lua_pop(_L, lua_gettop(_L)); // TODO: lua_settop(L, 0); ? 
         } else {
@@ -183,7 +190,7 @@ bool ScriptHost::LoadScript(const std::string& file)
         lua_pop(_L, 1); // TODO: verify this is correct
         return false;
     }
-    
+
     return true;
 }
 

src/luasandbox/require.h

@@ -8,11 +8,11 @@
 static inline int luasandbox_require(lua_State *L)
 {
     // get filename being required
-    const char* file = luaL_checkstring(L, -1);
+    const char* name = luaL_checkstring(L, -1);
 
     // check cache
     luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
-    int t = lua_getfield(L, -1, file);
+    int t = lua_getfield(L, -1, name);
     if (t != LUA_TNONE && t != LUA_TNIL) {
         lua_remove(L, -2); // remove _LOADED from stack
         return 1;
@@ -34,42 +34,47 @@ static inline int luasandbox_require(lua_State *L)
         return 0;
     }
 
+    std::string filename = name;
+    std::replace(filename.begin(), filename.end(), '.', '/');
+
     // load file to string
-    std::string* pscript = new std::string();
+    std::string pscript;
     // TODO: add support for package.path
     bool ok = false;
     for (const std::string prefix : {"scripts/", ""}) {
-        for (const std::string& folder : {std::string(""), std::string(file)+"/"}) {
-            for (const std::string suffix : {"", ".lua"}) {
-                ok = pack->ReadFile(prefix + folder + file + suffix, *pscript);
-                if (ok) break;
+        for (const std::string& part : {filename, filename+"/init"}) {
+            for (const std::string suffix : {".LUA", ".lua"}) {
+                ok = pack->ReadFile(prefix + part + suffix, pscript);
+                if (ok) {
+                    filename = prefix + part + suffix;
+                    break;
+                }
             }
-            if (ok) break;
+            if (ok)
+                break;
         }
-        if (ok) break;
+        if (ok)
+            break;
     }
     if (!ok) {
-        delete pscript;
         lua_pop(L, 2); // pop Tracker and _LOADED
-        luaL_error(L, "No such module: %s", file);
+        luaL_error(L, "No such module: %s", name);
         return 0;
     }
     lua_pop(L, 1); // pop Tracker
 
-    if (luaL_loadbufferx(L, pscript->c_str(), pscript->length(), file, "t") == LUA_OK) {
-        if (lua_pcall(L, 0, 1, 0) == LUA_OK) {
-            delete pscript;
+    if (luaL_loadbufferx(L, pscript.c_str(), pscript.length(), filename.c_str(), "t") == LUA_OK) {
+        lua_pushstring(L, name);
+        if (lua_pcall(L, 1, 1, 0) == LUA_OK) {
             lua_pushvalue(L, -1); // duplicate result
-            lua_setfield(L, -3, file);
+            lua_setfield(L, -3, name);
             lua_remove(L, -2); // remove _LOADED from stack
             return 1;
         } else {
-            delete pscript;
             lua_remove(L, -2); // remove _LOADED from stack
             lua_error(L);
         }
     } else {
-        delete pscript;
         lua_remove(L, -2); // remove _LOADED from stack
         lua_error(L);
     }