From 8073ca30fb7c6a01c323c13048e010a642a2aa6f Mon Sep 17 00:00:00 2001
From: yellows8 <yellows8@users.noreply.github.com>
Date: Mon, 26 Mar 2018 14:52:03 -0400
Subject: [PATCH] In save example, use SaveDataIterator to find what savedata
 to use, otherwise fallback to the original hard-coded TID + current-userID.

---
 fs/save/source/main.c | 68 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 54 insertions(+), 14 deletions(-)

diff --git a/fs/save/source/main.c b/fs/save/source/main.c
index d6b0c05..7f8d5b7 100644
--- a/fs/save/source/main.c
+++ b/fs/save/source/main.c
@@ -6,6 +6,38 @@
 
 //This example shows how to access savedata for (official) applications/games.
 
+Result get_save(u64 *titleID, u128 *userID)
+{
+    Result rc=0;
+    FsSaveDataIterator iterator;
+    size_t total_entries=0;
+    FsSaveDataInfo info;
+
+    rc = fsOpenSaveDataIterator(&iterator, FsSaveDataSpaceId_NandUser);//See libnx fs.h.
+    if (R_FAILED(rc)) {
+        printf("fsOpenSaveDataIterator() failed: 0x%x\n", rc);
+        return rc;
+    }
+
+    //Find the first savedata with FsSaveDataType_SaveData.
+    while(1) {
+        rc = fsSaveDataIteratorRead(&iterator, &info, 1, &total_entries);//See libnx fs.h.
+        if (R_FAILED(rc) || total_entries==0) break;
+
+        if (info.SaveDataType == FsSaveDataType_SaveData) {//Filter by FsSaveDataType_SaveData, however note that NandUser can have non-FsSaveDataType_SaveData.
+            *titleID = info.titleID;
+            *userID = info.userID;
+            return 0;
+        }
+    }
+
+    fsSaveDataIteratorClose(&iterator);
+
+    if (R_SUCCEEDED(rc)) return MAKERESULT(Module_Libnx, LibnxError_NotFound);
+
+    return rc;
+}
+
 int main(int argc, char **argv)
 {
     Result rc=0;
@@ -17,32 +49,40 @@ int main(int argc, char **argv)
     FsFileSystem tmpfs;
     u128 userID=0;
     bool account_selected=0;
-    u64 titleid=0x01007ef00011e000;//titleID of the save to mount, in this case BOTW.
+    u64 titleID=0x01007ef00011e000;//titleID of the save to mount, in this case BOTW.
 
     gfxInitDefault();
     consoleInit(NULL);
 
     //Get the userID for save mounting. To mount common savedata, use FS_SAVEDATA_USERID_COMMONSAVE.
-    rc = accountInitialize();
-    if (R_FAILED(rc)) {
-        printf("accountInitialize() failed: 0x%x\n", rc);
-    }
-
-    if (R_SUCCEEDED(rc)) {
-        rc = accountGetActiveUser(&userID, &account_selected);
-        accountExit();
 
+    //Try to find savedata to use with get_save() first, otherwise fallback to the above hard-coded TID + the userID from accountGetActiveUser(). Note that you can use either method.
+    if (R_FAILED(get_save(&titleID, &userID))) {
+        rc = accountInitialize();
         if (R_FAILED(rc)) {
-            printf("accountGetActiveUser() failed: 0x%x\n", rc);
+            printf("accountInitialize() failed: 0x%x\n", rc);
         }
-        else if(!account_selected) {
-            printf("No user is currently selected.\n");
-            rc = -1;
+
+        if (R_SUCCEEDED(rc)) {
+            rc = accountGetActiveUser(&userID, &account_selected);
+            accountExit();
+
+            if (R_FAILED(rc)) {
+                printf("accountGetActiveUser() failed: 0x%x\n", rc);
+            }
+            else if(!account_selected) {
+                printf("No user is currently selected.\n");
+                rc = -1;
+            }
         }
     }
 
     if (R_SUCCEEDED(rc)) {
-        rc = fsMount_SaveData(&tmpfs, titleid, userID);//See also libnx fs.h.
+        printf("Using titleID=0x%016lx userID: 0x%lx 0x%lx\n", titleID, (u64)(userID>>64), (u64)userID);
+    }
+
+    if (R_SUCCEEDED(rc)) {
+        rc = fsMount_SaveData(&tmpfs, titleID, userID);//See also libnx fs.h.
         if (R_FAILED(rc)) {
             printf("fsMount_SaveData() failed: 0x%x\n", rc);
         }