fix require (#908)

* fix require

* Refactor smlua_find_mod_file

* formatting

* initialize arrays for consistency

* normalize relative path in mod_allocate_file instead (fix mod dev mode)

* do cleanup

* Remove useless branch + add comments

* fix mod_file_exists

* WIP: cache mod files at root (LIVE RELOAD IS BROKEN)

* Fix live reload

* remove useless declaration (??)

* fix incorrect top handling

* cleanup x2

* stupid

* loading sentinel + mark top level files as loading

* address dj's comment

src/pc/lua/smlua.c

@@ -362,7 +362,19 @@ void smlua_init(void) {
             }
 
             gLuaActiveModFile = file;
-            smlua_load_script(mod, file, i, true);
+
+            // file has been required by some module before this
+            if (!smlua_get_cached_module_result(L, mod, file)) {
+                smlua_mark_module_as_loading(L, mod, file);
+
+                s32 prevTop = lua_gettop(L);
+                int rc = smlua_load_script(mod, file, i, true);
+
+                if (rc == LUA_OK) {
+                    smlua_cache_module_result(L, mod, file, prevTop);
+                }
+            }
+
             lua_settop(L, 0);
         }
         gLuaActiveMod = NULL;

src/pc/lua/smlua_hooks.c

@@ -100,6 +100,7 @@ int smlua_hook_event(lua_State* L) {
 
     hook->reference[hook->count] = ref;
     hook->mod[hook->count] = gLuaActiveMod;
+    hook->modFile[hook->count] = gLuaActiveModFile;
     hook->count++;
 
     return 1;

src/pc/lua/smlua_live_reload.c

@@ -1,5 +1,6 @@
 #include <stdbool.h>
 #include "smlua.h"
+#include "smlua_require.h"
 #include "pc/mods/mods.h"
 #include "pc/mods/mods_utils.h"
 
@@ -343,16 +344,8 @@ static void smlua_reload_module(lua_State *L, struct Mod* mod, struct ModFile *f
     // only handle loaded Lua modules
     if (!file->isLoadedLuaModule) { return; }
 
-    // build registry key for this mod's loaded table
-    char registryKey[SYS_MAX_PATH + 16];
-    snprintf(registryKey, sizeof(registryKey), "mod_loaded_%s", mod->relativePath);
-
     // get per-mod "loaded" table
-    lua_getfield(L, LUA_REGISTRYINDEX, registryKey);      // ..., loadedTable
-    if (!lua_istable(L, -1)) {
-        lua_pop(L, 1);
-        return;
-    }
+    smlua_get_or_create_mod_loaded_table(L, mod);
 
     // get the old module table: loadedTable[file->relativePath]
     lua_getfield(L, -1, file->relativePath);              // ..., loadedTable, oldMod

src/pc/lua/smlua_require.c

@@ -4,47 +4,89 @@
 #include "pc/mods/mods_utils.h"
 #include "pc/fs/fmem.h"
 
+#define LOADING_SENTINEL ((void*)-1)
+
 // table to track loaded modules per mod
-static void smlua_init_mod_loaded_table(lua_State* L, const char* modPath) {
-    // Create a unique registry key for this mod's loaded table
-    char registryKey[SYS_MAX_PATH + 16];
-    snprintf(registryKey, sizeof(registryKey), "mod_loaded_%s", modPath);
+void smlua_get_or_create_mod_loaded_table(lua_State* L, struct Mod* mod) {
+    char registryKey[SYS_MAX_PATH + 16] = "";
+    snprintf(registryKey, sizeof(registryKey), "mod_loaded_%s", mod->relativePath);
 
     lua_getfield(L, LUA_REGISTRYINDEX, registryKey);
     if (lua_isnil(L, -1)) {
         lua_pop(L, 1);
         lua_newtable(L);
+        lua_pushvalue(L, -1);
         lua_setfield(L, LUA_REGISTRYINDEX, registryKey);
-    } else {
-        lua_pop(L, 1);
     }
 }
 
+bool smlua_get_cached_module_result(lua_State* L, struct Mod* mod, struct ModFile* file) {
+    smlua_get_or_create_mod_loaded_table(L, mod);
+    lua_getfield(L, -1, file->relativePath);
+
+    if (lua_touserdata(L, -1) == LOADING_SENTINEL) {
+        LOG_LUA_LINE("loop or previous error loading module '%s'", file->relativePath);
+        lua_pop(L, 1); // pop sentinel
+        lua_pushnil(L);
+
+        return true;
+    }
+
+    if (lua_isnil(L, -1)) {
+        // not cached
+        lua_pop(L, 2); // pop nil and loaded table
+        return false;
+    }
+
+    // cached, remove loaded table and leave value on top
+    lua_remove(L, -2);
+    return true;
+}
+
+void smlua_mark_module_as_loading(lua_State* L, struct Mod* mod, struct ModFile* file) {
+    smlua_get_or_create_mod_loaded_table(L, mod);
+    lua_pushlightuserdata(L, LOADING_SENTINEL);
+    lua_setfield(L, -2, file->relativePath);
+    lua_pop(L, 1); // pop loaded table
+}
+ 
+void smlua_cache_module_result(lua_State* L, struct Mod* mod, struct ModFile* file, s32 prevTop) {
+    if (lua_gettop(L) == prevTop) {
+        lua_pushboolean(L, 1);
+    } else if (lua_isnil(L, -1)) {
+        lua_pop(L, 1);
+        lua_pushboolean(L, 1);
+    }
+
+    smlua_get_or_create_mod_loaded_table(L, mod);
+
+    lua_pushvalue(L, -2); // duplicate result
+    lua_setfield(L, -2, file->relativePath); // loaded[file->relativePath] = result
+    lua_pop(L, 1); // pop loaded table
+}
+
 static struct ModFile* smlua_find_mod_file(const char* moduleName) {
-    char relativeDir[SYS_MAX_PATH] = "";
+    char basePath[SYS_MAX_PATH] = "";
+    char absolutePath[SYS_MAX_PATH] = "";
 
     if (!gLuaActiveMod) {
         return NULL;
     }
 
+    // get the directory of the current file
     if (gLuaActiveModFile) {
-        path_get_folder(gLuaActiveModFile->relativePath, relativeDir);
+        path_get_folder(gLuaActiveModFile->relativePath, basePath);
     }
 
-    bool hasRelativeDir = strlen(relativeDir) > 0;
+    // resolve moduleName to a path relative to mod root
+    resolve_relative_path(basePath, moduleName, absolutePath);
 
-    struct ModFile* bestPick = NULL;
-    int bestRelativeDepth = INT_MAX;
-    int bestTotalDepth = INT_MAX;
-    bool foundRelativeFile = false;
-
-    char rawName[SYS_MAX_PATH] = "";
     char luaName[SYS_MAX_PATH] = "";
     char luacName[SYS_MAX_PATH] = "";
-    snprintf(rawName, SYS_MAX_PATH, "/%s", moduleName);
-    snprintf(luaName, SYS_MAX_PATH, "/%s.lua", moduleName);
-    snprintf(luacName, SYS_MAX_PATH, "/%s.luac", moduleName);
+    snprintf(luaName, SYS_MAX_PATH, "%s.lua", absolutePath);
+    snprintf(luacName, SYS_MAX_PATH, "%s.luac", absolutePath);
 
+    // since mods' relativePaths are relative to the mod's root, we can do a direct comparison
     for (int i = 0; i < gLuaActiveMod->fileCount; i++) {
         struct ModFile* file = &gLuaActiveMod->files[i];
 
@@ -59,36 +101,12 @@ static struct ModFile* smlua_find_mod_file(const char* moduleName) {
         }
 
         // check for match
-        if (!str_ends_with(file->relativePath, rawName) && !str_ends_with(file->relativePath, luaName) && !str_ends_with(file->relativePath, luacName)) {
-            continue;
-        }
-
-        // get total path depth
-        int totalDepth = path_depth(file->relativePath);
-
-        // make sure we never load the old-style lua files with require()
-        if (totalDepth < 1) {
-            continue;
-        }
-
-        // get relative path depth
-        int relativeDepth = INT_MAX;
-        if (hasRelativeDir && path_is_relative_to(file->relativePath, relativeDir)) {
-            relativeDepth = path_depth(file->relativePath + strlen(relativeDir));
-            foundRelativeFile = true;
-        }
-
-        // pick new best
-        // relative files will always win against absolute files
-        // other than that, shallower files will win
-        if (relativeDepth < bestRelativeDepth || (!foundRelativeFile && totalDepth < bestTotalDepth)) {
-            bestPick = file;
-            bestRelativeDepth = relativeDepth;
-            bestTotalDepth = totalDepth;
+        if (!strcmp(file->relativePath, luaName) || !strcmp(file->relativePath, luacName)) {
+            return file;
         }
     }
 
-    return bestPick;
+    return NULL;
 }
 
 static int smlua_custom_require(lua_State* L) {
@@ -96,69 +114,47 @@ static int smlua_custom_require(lua_State* L) {
 
     struct Mod* activeMod = gLuaActiveMod;
     if (!activeMod) {
-        LOG_LUA("require() called outside of mod context");
+        LOG_LUA_LINE("require() called outside of mod context");
         return 0;
     }
 
-    // create registry key for this mod's loaded table
-    char registryKey[SYS_MAX_PATH + 16] = "";
-    snprintf(registryKey, sizeof(registryKey), "mod_loaded_%s", activeMod->relativePath);
-
-    // get or create the mod's loaded table
-    lua_getfield(L, LUA_REGISTRYINDEX, registryKey);
-    if (lua_isnil(L, -1)) {
-        lua_pop(L, 1);
-        lua_newtable(L);
-        lua_pushvalue(L, -1);
-        lua_setfield(L, LUA_REGISTRYINDEX, registryKey);
+    if (str_ends_with(moduleName, "/") || str_ends_with(moduleName, "\\")) {
+        LOG_LUA_LINE("cannot require a directory");
+        return 0;
     }
 
     // find the file in mod files
     struct ModFile* file = smlua_find_mod_file(moduleName);
     if (!file) {
-        LOG_LUA("module '%s' not found in mod files", moduleName);
-        lua_pop(L, 1); // pop table
+        LOG_LUA_LINE("module '%s' not found in mod files", moduleName);
         return 0;
     }
 
-    // check if module is already loaded
-    lua_getfield(L, -1, file->relativePath);
-    if (!lua_isnil(L, -1)) {
-        // module already loaded, return it
-        return 1;
-    }
-    lua_pop(L, 1); // pop nil value
-
-    // mark module as "loading" to prevent recursion
-    lua_pushboolean(L, 1);
-    lua_setfield(L, -2, file->relativePath);
-
-    // cache the previous mod file
-    struct ModFile* prevModFile = gLuaActiveModFile;
-    s32 prevTop = lua_gettop(L);
-
     // tag it as a loaded lua module
     file->isLoadedLuaModule = true;
 
-    // load and execute
-    gLuaActiveModFile = file;
-    smlua_load_script(activeMod, file, activeMod->index, false);
-    gLuaActiveModFile = prevModFile;
-
-    // if the module didn't return anything, use true
-    if (prevTop == lua_gettop(L)) {
-        lua_pushboolean(L, 1);
-    } else if (lua_isnil(L, -1)) {
-        lua_pop(L, 1);
-        lua_pushboolean(L, 1);
+    // check cache first
+    if (smlua_get_cached_module_result(L, activeMod, file)) {
+        return 1;
     }
 
-    // store in loaded table
-    lua_pushvalue(L, -1); // duplicate return value
-    lua_setfield(L, -3, file->relativePath); // loaded[file->relativePath] = return_value
+    // mark module as "loading" to prevent recursion
+    smlua_mark_module_as_loading(L, activeMod, file);
 
-    // clean up stack
-    lua_remove(L, -2);
+    // cache the previous mod file
+    struct ModFile* prevModFile = gLuaActiveModFile;
+
+    // load and execute
+    gLuaActiveModFile = file;
+    s32 prevTop = lua_gettop(L);
+
+    int rc = smlua_load_script(activeMod, file, activeMod->index, false);
+
+    if (rc == LUA_OK) {
+        smlua_cache_module_result(L, activeMod, file, prevTop);
+    }
+
+    gLuaActiveModFile = prevModFile;
 
     return 1; // return the module value
 }
@@ -179,6 +175,7 @@ void smlua_init_require_system(void) {
     // initialize loaded tables for each mod
     for (int i = 0; i < gActiveMods.entryCount; i++) {
         struct Mod* mod = gActiveMods.entries[i];
-        smlua_init_mod_loaded_table(L, mod->relativePath);
+        smlua_get_or_create_mod_loaded_table(L, mod);
+        lua_pop(L, 1); // pop loaded table
     }
-}
+}

src/pc/lua/smlua_require.h

@@ -3,9 +3,11 @@
 
 #include "smlua.h"
 
-void smlua_require_update(lua_State* L);
 void smlua_bind_custom_require(lua_State* L);
-void smlua_reload_module(lua_State *L, struct Mod* mod, struct ModFile *file);
+void smlua_get_or_create_mod_loaded_table(lua_State* L, struct Mod* mod);
+bool smlua_get_cached_module_result(lua_State* L, struct Mod* mod, struct ModFile* file);
+void smlua_mark_module_as_loading(lua_State* L, struct Mod* mod, struct ModFile* file);
+void smlua_cache_module_result(lua_State* L, struct Mod* mod, struct ModFile* file, s32 prevTop);
 void smlua_init_require_system(void);
 
 #endif

src/pc/lua/utils/smlua_misc_utils.c

@@ -539,9 +539,17 @@ void set_environment_region(u8 index, s16 value) {
 bool mod_file_exists(const char* filename) {
     if (gLuaActiveMod == NULL) { return false; }
 
+    char normPath[SYS_MAX_PATH] = { 0 };
+
+    if (snprintf(normPath, sizeof(normPath), "%s", filename) < 0) {
+        LOG_ERROR("Failed to copy filename for normalization: %s", filename);
+    }
+
+    normalize_path(normPath);
+
     for (s32 i = 0; i < gLuaActiveMod->fileCount; i++) {
         struct ModFile* file = &gLuaActiveMod->files[i];
-        if (!strcmp(file->relativePath, filename)) {
+        if (!strcmp(file->relativePath, normPath)) {
             return true;
         }
     }

src/pc/mods/mod.c

@@ -245,15 +245,22 @@ static struct ModFile* mod_allocate_file(struct Mod* mod, char* relativePath) {
     memset(file, 0, sizeof(struct ModFile));
 
     // set relative path
-    if (snprintf(file->relativePath, SYS_MAX_PATH - 1, "%s", relativePath) < 0) {
-        LOG_ERROR("Failed to remember relative path '%s'", relativePath);
+    char normPath[SYS_MAX_PATH] = { 0 };
+    if (snprintf(normPath, sizeof(normPath), "%s", relativePath) < 0) {
+        LOG_ERROR("Failed to copy relative path for normalization: %s", relativePath);
+    }
+
+    normalize_path(normPath);
+
+    if (snprintf(file->relativePath, SYS_MAX_PATH - 1, "%s", normPath) < 0) {
+        LOG_ERROR("Failed to remember relative path '%s'", normPath);
         return NULL;
     }
 
     // figure out full path
     char fullPath[SYS_MAX_PATH] = { 0 };
     if (!mod_file_full_path(fullPath, mod, file)) {
-        LOG_ERROR("Failed to concat path: '%s' + '%s'", mod->basePath, relativePath);
+        LOG_ERROR("Failed to concat path: '%s' + '%s'", mod->basePath, normPath);
         return NULL;
     }
 

src/pc/mods/mods_utils.c

@@ -244,6 +244,47 @@ int path_depth(const char* path) {
     return depth;
 }
 
+void resolve_relative_path(const char* base, const char* path, char* output) {
+    char combined[SYS_MAX_PATH] = "";
+
+    // If path is absolute, copy as is. Otherwise, combine base and relative path
+    if (path[0] == '/' || path[0] == '\\') {
+        snprintf(combined, sizeof(combined), "%s", path);
+    } else {
+        snprintf(combined, sizeof(combined), "%s/%s", base, path);
+    }
+
+    char* tokens[64];
+    int tokenCount = 0;
+
+    // Tokenize path by separators
+    char* token = strtok(combined, "/\\");
+    while (token && tokenCount < 64) {
+        if (strcmp(token, "..") == 0) {
+            // Pop last token to go up a directory
+            if (tokenCount > 0) { tokenCount--; }
+
+        // Ignore "." (current directory) or empty tokens
+        } else if (strcmp(token, ".") != 0 && token[0] != '\0') {
+            tokens[tokenCount++] = token;
+        }
+
+        token = strtok(NULL, "/\\");
+    }
+
+    output[0] = '\0';
+
+    // Build output path from tokens
+    for (int i = 0; i < tokenCount; i++) {
+        if (i > 0) {
+            strncat(output, "/", SYS_MAX_PATH - strlen(output) - 1);
+        }
+        strncat(output, tokens[i], SYS_MAX_PATH - strlen(output) - 1);
+    }
+
+    normalize_path(output);
+}
+
 bool path_is_relative_to(const char* fullPath, const char* baseDir) {
     return strncmp(fullPath, baseDir, strlen(baseDir)) == 0;
 }

src/pc/mods/mods_utils.h

@@ -21,6 +21,7 @@ bool concat_path(char* destination, char* path, char* fname);
 char* path_basename(char* path);
 void path_get_folder(char* path, char* outpath);
 int path_depth(const char* path);
+void resolve_relative_path(const char* base, const char* path, char* output);
 bool path_is_relative_to(const char* fullPath, const char* baseDir);
 bool directory_sanity_check(struct dirent* dir, char* dirPath, char* outPath);