rpc, wallet: Expose database format in getwalletinfo

src/wallet/bdb.h

@@ -146,6 +146,7 @@ public:
     /** Return path to main database filename */
     std::string Filename() override { return (env->Directory() / strFile).string(); }
 
+    std::string Format() override { return "bdb"; }
     /**
      * Pointer to shared database environment.
      *

src/wallet/db.h

@@ -144,6 +144,8 @@ public:
     /** Return path to main database file for logs and error messages. */
     virtual std::string Filename() = 0;
 
+    virtual std::string Format() = 0;
+
     std::atomic<unsigned int> nUpdateCounter;
     unsigned int nLastSeen;
     unsigned int nLastFlushed;
@@ -190,6 +192,7 @@ public:
     void IncrementUpdateCounter() override { ++nUpdateCounter; }
     void ReloadDbEnv() override {}
     std::string Filename() override { return "dummy"; }
+    std::string Format() override { return "dummy"; }
     std::unique_ptr<DatabaseBatch> MakeBatch(bool flush_on_close = true) override { return MakeUnique<DummyBatch>(); }
 };
 

src/wallet/rpcwallet.cpp

@@ -2422,6 +2422,7 @@ static RPCHelpMan getwalletinfo()
                         {
                         {RPCResult::Type::STR, "walletname", "the wallet name"},
                         {RPCResult::Type::NUM, "walletversion", "the wallet version"},
+                        {RPCResult::Type::STR, "format", "the database format (bdb or sqlite)"},
                         {RPCResult::Type::STR_AMOUNT, "balance", "DEPRECATED. Identical to getbalances().mine.trusted"},
                         {RPCResult::Type::STR_AMOUNT, "unconfirmed_balance", "DEPRECATED. Identical to getbalances().mine.untrusted_pending"},
                         {RPCResult::Type::STR_AMOUNT, "immature_balance", "DEPRECATED. Identical to getbalances().mine.immature"},
@@ -2465,6 +2466,7 @@ static RPCHelpMan getwalletinfo()
     int64_t kp_oldest = pwallet->GetOldestKeyPoolTime();
     obj.pushKV("walletname", pwallet->GetName());
     obj.pushKV("walletversion", pwallet->GetVersion());
+    obj.pushKV("format", pwallet->GetDatabase().Format());
     obj.pushKV("balance", ValueFromAmount(bal.m_mine_trusted));
     obj.pushKV("unconfirmed_balance", ValueFromAmount(bal.m_mine_untrusted_pending));
     obj.pushKV("immature_balance", ValueFromAmount(bal.m_mine_immature));

src/wallet/scriptpubkeyman.h

@@ -33,7 +33,7 @@ class WalletStorage
 public:
     virtual ~WalletStorage() = default;
     virtual const std::string GetDisplayName() const = 0;
-    virtual WalletDatabase& GetDatabase() = 0;
+    virtual WalletDatabase& GetDatabase() const = 0;
     virtual bool IsWalletFlagSet(uint64_t) const = 0;
     virtual void UnsetBlankWalletFlag(WalletBatch&) = 0;
     virtual bool CanSupportFeature(enum WalletFeature) const = 0;

src/wallet/sqlite.h

@@ -105,6 +105,7 @@ public:
     void IncrementUpdateCounter() override { ++nUpdateCounter; }
 
     std::string Filename() override { return m_file_path; }
+    std::string Format() override { return "sqlite"; }
 
     /** Make a SQLiteBatch connected to this database */
     std::unique_ptr<DatabaseBatch> MakeBatch(bool flush_on_close = true) override;

src/wallet/wallet.h

@@ -739,7 +739,7 @@ public:
     {
         return *database;
     }
-    WalletDatabase& GetDatabase() override { return *database; }
+    WalletDatabase& GetDatabase() const override { return *database; }
 
     /**
      * Select a set of coins such that nValueRet >= nTargetValue and at least