iidxhook-util: Add option to configure path for storing settings

Additional flexibility to cover use-cases like storing this
data on a separate partition which keeps the game data folder
clean and read-only.

src/main/iidxhook-util/settings.c

@@ -13,6 +13,7 @@
 #include "util/defs.h"
 #include "util/fs.h"
 #include "util/log.h"
+#include "util/mem.h"
 #include "util/str.h"
 
 /* ------------------------------------------------------------------------- */
@@ -32,6 +33,24 @@ static const struct hook_symbol settings_hook_syms[] = {
 };
 
 static bool settings_folders_checked;
+static char settings_path[MAX_PATH] = ".\\";
+
+/* ------------------------------------------------------------------------- */
+
+static void settings_build_new_path(const char* orig_path, char* new_path, size_t new_path_len)
+{
+    size_t settings_path_len;
+
+    settings_path_len = strlen(settings_path);
+
+    log_assert(settings_path_len + strlen(orig_path) < new_path_len);
+
+    strcpy(new_path, settings_path);
+    strcat(new_path, orig_path);
+
+    /* Remove : of drive letter. Multiple \ are fine and handled by windows */
+    new_path[settings_path_len + 1] = '\\';
+}
 
 /* ------------------------------------------------------------------------- */
 
@@ -44,8 +63,8 @@ BOOL WINAPI my_CreateDirectoryA(
         lpPathName[1] == ':') {
         char new_path[MAX_PATH];
 
-        strcpy(new_path, lpPathName);
-        new_path[1] = '\\';
+        settings_build_new_path(lpPathName, new_path, sizeof(new_path));
+
         log_misc("(CreateDir) Remapped settings path %s", new_path);
 
         return real_CreateDirectoryA(new_path, lpSecurityAttributes);
@@ -61,43 +80,88 @@ void settings_hook_init(void)
     hook_table_apply(
         NULL, "kernel32.dll", settings_hook_syms, lengthof(settings_hook_syms));
 
-    log_info("Inserted settings hooks");
+    log_info("Inserted settings hooks, settings path: %s", settings_path);
+}
+
+void settings_hook_set_path(const char* path)
+{    
+    size_t len;
+
+    len = strlen(path);
+
+    log_assert(path > 0);
+    log_assert(len < MAX_PATH);
+
+    strcpy(settings_path, path);
+
+    /* Ensure trailing \\ to allow simple concatinations in hooks */
+    if (settings_path[len - 1] != '\\') {
+        log_assert(len + 1 < MAX_PATH);
+
+        settings_path[len] = '\\';
+        settings_path[len + 1] = '\0';
+    }
+
+    log_info("Settings path: %s", settings_path);
 }
 
 HRESULT
 settings_hook_dispatch_irp(struct irp *irp)
 {
     if (irp->op == IRP_OP_OPEN &&
-        (irp->open_filename[0] == L'd' || irp->open_filename[0] == L'e' ||
-         irp->open_filename[0] == L'f') &&
-        irp->open_filename[1] == L':') {
-        char *log_str;
+            (irp->open_filename[0] == L'd' || irp->open_filename[0] == L'e' ||
+            irp->open_filename[0] == L'f') &&
+            irp->open_filename[1] == L':') {
+        HRESULT result;
+        char new_path[MAX_PATH];
+        const wchar_t *old_filename_wstr;
+        wchar_t *filename_wstr;
+        char *filename_cstr;
 
-        ((wchar_t *) irp->open_filename)[1] = L'\\';
+        log_assert(wstr_narrow(irp->open_filename, &filename_cstr));
 
-        wstr_narrow(irp->open_filename, &log_str);
-        log_misc("Remapped settings path %s", log_str);
-        free(log_str);
+        settings_build_new_path(filename_cstr, new_path, sizeof(new_path));
 
-        /* Create local settings folders if not available */
+        free(filename_cstr);
+
+        log_misc("Remapped settings path to %s", new_path);
+
+        filename_wstr = str_widen(new_path);
+
+        /* Temporarily swap open_filename */
+        old_filename_wstr = irp->open_filename;
+        irp->open_filename = filename_wstr;
+
+        /* Create settings folders if not available */
         if (!settings_folders_checked) {
             settings_folders_checked = true;
 
             for (char c = 'd'; c <= 'f'; c++) {
-                char str[3];
+                char new_path_folder[MAX_PATH];
+                size_t settings_path_len = strlen(settings_path);
 
-                str[0] = c;
-                str[1] = '\\';
-                str[2] = '\0';
+                log_assert(settings_path_len + 3 < MAX_PATH);
 
-                if (!path_exists(str)) {
-                    log_misc("Creating local settings folder %s\\", str);
-                    CreateDirectoryA(str, NULL);
+                strcpy(new_path_folder, settings_path);
+
+                new_path_folder[settings_path_len] = c;
+                new_path_folder[settings_path_len + 1] = '\\';
+                new_path_folder[settings_path_len + 2] = '\0';
+
+                if (!path_exists(new_path_folder)) {
+                    log_misc("Creating local settings folder %s", new_path_folder);
+                    CreateDirectoryA(new_path_folder, NULL);
                 }
             }
         }
 
-        return iohook_invoke_next(irp);
+        result = iohook_invoke_next(irp);
+
+        /* Revert to original irp */
+        irp->open_filename = old_filename_wstr;
+        free(filename_wstr);
+
+        return result;
     }
 
     return iohook_invoke_next(irp);

src/main/iidxhook-util/settings.h

@@ -4,12 +4,21 @@
 #include "hook/iohook.h"
 
 /**
- * Remaps the paths for the settings drives d:\, e:\ and f:\
- * to local folders e\ and f\.
- * Needed on IIDX 9th to Sirius.
+ * Remaps the paths for storing "settings data" that are usually stored on the
+ * drives d:\, e:\ and f:\ by the game. This defaults to the local folders
+ * d\, e\ and f\.
+ * 
+ * Required hook for 9th to Lincle.
  */
 void settings_hook_init(void);
 
+/**
+ * Change the path where settings file are stored.
+ * 
+ * @param path Destination path for storage, relative or absolute.
+ */
+void settings_hook_set_path(const char* path);
+
 /**
  * iohook dispatch function
  */