support correct filename on custom root path

Core/MMKV.cpp

@@ -343,11 +343,7 @@ void MMKV::close() {
     SCOPED_LOCK(g_instanceLock);
     m_lock->lock();
 
-#ifndef MMKV_ANDROID
     auto itr = g_instanceDic->find(m_mmapKey);
-#else
-    auto itr = g_instanceDic->find(m_mmapID);
-#endif
     if (itr != g_instanceDic->end()) {
         g_instanceDic->erase(itr);
     }
@@ -1308,8 +1304,14 @@ bool MMKV::backupOneToDirectory(const string &mmapID, const MMKVPath_t &dstDir,
     auto dstPath = dstDir + MMKV_PATH_SLASH + encodePath;
     auto mmapKey = mmapedKVKey(mmapID, rootPath);
 #ifdef MMKV_ANDROID
-    // historically Android mistakenly use mmapKey as mmapID
-    auto srcPath = *rootPath + MMKV_PATH_SLASH + encodeFilePath(mmapKey, *rootPath);
+    string srcPath;
+    auto correctPath = *rootPath + MMKV_PATH_SLASH + encodePath;
+    if (srcDir && isFileExist(correctPath)) {
+        srcPath = correctPath;
+    } else {
+        // historically Android mistakenly use mmapKey as mmapID
+        srcPath = *rootPath + MMKV_PATH_SLASH + encodeFilePath(mmapKey, *rootPath);
+    }
 #else
     auto srcPath = *rootPath + MMKV_PATH_SLASH + encodePath;
 #endif
@@ -1491,8 +1493,14 @@ bool MMKV::restoreOneFromDirectory(const string &mmapID, const MMKVPath_t &srcDi
     auto srcPath = srcDir + MMKV_PATH_SLASH + encodePath;
     auto mmapKey = mmapedKVKey(mmapID, rootPath);
 #ifdef MMKV_ANDROID
-    // historically Android mistakenly use mmapKey as mmapID
-    auto dstPath = *rootPath + MMKV_PATH_SLASH + encodeFilePath(mmapKey, *rootPath);
+    string dstPath;
+    auto correctPath = *rootPath + MMKV_PATH_SLASH + encodePath;
+    if (dstDir && isFileExist(correctPath)) {
+        dstPath = correctPath;
+    } else {
+        // historically Android mistakenly use mmapKey as mmapID
+        dstPath = *rootPath + MMKV_PATH_SLASH + encodeFilePath(mmapKey, *rootPath);
+    }
 #else
     auto dstPath = *rootPath + MMKV_PATH_SLASH + encodePath;
 #endif

Core/MMKV.h

@@ -95,7 +95,6 @@ concept MMKV_SUPPORTED_VALUE_TYPE = MMKV_SUPPORTED_PRIMITIVE_VALUE_TYPE<T> || MM
 
 class MMKV {
 #ifndef MMKV_ANDROID
-    std::string m_mmapKey;
     MMKV(const std::string &mmapID, MMKVMode mode, std::string *cryptKey, MMKVPath_t *rootPath, size_t expectedCapacity = 0);
 #else // defined(MMKV_ANDROID)
     mmkv::FileLock *m_fileModeLock;
@@ -109,6 +108,7 @@ class MMKV {
 
     ~MMKV();
 
+    std::string m_mmapKey;
     std::string m_mmapID;
     const MMKVMode m_mode;
     MMKVPath_t m_path;

Core/MMKV_Android.cpp

@@ -40,7 +40,7 @@ extern unordered_map<string, MMKV *> *g_instanceDic;
 extern ThreadLock *g_instanceLock;
 
 MMKV::MMKV(const string &mmapID, int size, MMKVMode mode, const string *cryptKey, const string *rootPath, size_t expectedCapacity)
-    : m_mmapID((mode & MMKV_BACKUP) ? mmapID : mmapedKVKey(mmapID, rootPath)) // historically Android mistakenly use mmapKey as mmapID
+    : m_mmapID(mmapID)
     , m_mode(mode)
     , m_path(mappedKVPathWithID(m_mmapID, mode, rootPath))
     , m_crcPath(crcPathWithID(m_mmapID, mode, rootPath))
@@ -157,7 +157,18 @@ MMKV *MMKV::mmkvWithID(const string &mmapID, int size, MMKVMode mode, const stri
         }
         MMKVInfo("prepare to load %s (id %s) from rootPath %s", mmapID.c_str(), mmapKey.c_str(), rootPath->c_str());
     }
-    auto kv = new MMKV(mmapID, size, mode, cryptKey, rootPath, expectedCapacity);
+
+    string realID;
+    auto correctPath = mappedKVPathWithID(mmapID, mode, rootPath);
+    if ((mode & MMKV_BACKUP) || (rootPath && isFileExist(correctPath))) {
+        // it's successfully migrated to the correct path by newer version of MMKV
+        realID = mmapID;
+    } else {
+        // historically Android mistakenly use mmapKey as mmapID
+        realID = mmapKey;
+    }
+    auto kv = new MMKV(realID, size, mode, cryptKey, rootPath, expectedCapacity);
+    kv->m_mmapKey = mmapKey;
     (*g_instanceDic)[mmapKey] = kv;
     return kv;
 }
@@ -178,6 +189,7 @@ MMKV *MMKV::mmkvWithAshmemFD(const string &mmapID, int fd, int metaFD, const str
         return kv;
     }
     auto kv = new MMKV(mmapID, fd, metaFD, cryptKey);
+    kv->m_mmapKey = mmapID;
     (*g_instanceDic)[mmapID] = kv;
     return kv;
 }

Core/MMKV_IO.cpp

@@ -1549,7 +1549,15 @@ bool MMKV::removeStorage(const std::string &mmapID, MMKVPath_t *relatePath) {
     }
     auto mmapKey = mmapedKVKey(mmapID, relatePath);
 #ifdef MMKV_ANDROID
-    auto &realID = mmapKey; // historically Android mistakenly use mmapKey as mmapID
+    std::string realID;
+    auto correctPath = mappedKVPathWithID(mmapID, MMKV_SINGLE_PROCESS, relatePath);
+    if (relatePath && isFileExist(correctPath)) {
+        // it's successfully migrated to the correct path by newer version of MMKV
+        realID = mmapID;
+    } else {
+        // historically Android mistakenly use mmapKey as mmapID
+        realID = mmapKey;
+    }
 #else
     auto &realID = mmapID;
 #endif