Merge bitcoin/bitcoin#26606: wallet: Implement independent BDB parser

d51fbab4b32d56765e8faab6ad01245fb259b0ca wallet, test: Be able to always swap BDB endianness (Ava Chow)
0b753156ce60c29efb2386954ba7555ad8f642f5 test: Test bdb_ro dump of wallet without reset LSNs (Ava Chow)
c1984f128284589423b7e0cc06c9a3b23a242d95 test: Test dumping dbs with overflow pages (Ava Chow)
fd7b16e391ed320e35255157a28be14c947ef30a test: Test dumps of other endian BDB files (Ava Chow)
6ace3e953f0864bd7818f040c59a1bc70aa47512 bdb: Be able to make byteswapped databases (Ava Chow)
d9878903fb34939dee8e1462f079acc68110253d Error if LSNs are not reset (Ava Chow)
4d7a3ae78e55f25868979f1bd920857a4aecb825 Berkeley RO Database fuzz test (TheCharlatan)
3568dce9e93295674cdf5458c5bdf93ff01fd0a2 tests: Add BerkeleyRO to db prefix tests (Ava Chow)
70cfbfdadf16d3b115309c6938f07ef5b96c7cc1 wallettool: Optionally use BERKELEY_RO as format when dumping BDB wallets (Ava Chow)
dd57713f6ede3d46e97ee7df87c10001b0bf4c3d Add MakeBerkeleyRODatabase (Ava Chow)
6e50bee67d1d58aecd8a0ce8b7c3f5a7979365f5 Implement handling of other endianness in BerkeleyRODatabase (Ava Chow)
cdd61c9cc108df8e13f4e3891ff2c96355b3ee38 wallet: implement independent BDB deserializer in BerkeleyRODatabase (Ava Chow)
ecba23097955dad7208baa687fc405c846aee794 wallet: implement BerkeleyRODatabase::Backup (Ava Chow)
0c8e72847603540bb29b8b8aeb80fa3f2e3a2c9a wallet: implement BerkeleyROBatch (Ava Chow)
756ff9b478484b17c4a6e65c171c2e4fecb21ad4 wallet: add dummy BerkeleyRODatabase and BerkeleyROBatch classes (Ava Chow)
ca18aea5c4975ace4e307be96c74641d203fa389 Add AutoFile::seek and tell (Ava Chow)

Pull request description:

  Split from #26596

  This PR adds `BerkeleyRODatabase` which is an independent implementation of a BDB file parser. It provides read only access to a BDB file, and can therefore be used as a read only database backend for wallets. This will be used for dumping legacy wallet records and migrating legacy wallets without the need for BDB itself.

  Wallettool's `dump` command is changed to use `BerkeleyRODatabase` instead of `BerkeleyDatabase` (and `CWallet` itself) to demonstrate that this parser works and to test it against the existing wallettool functional tests.

ACKs for top commit:
  josibake:
    reACK https://github.com/bitcoin/bitcoin/commit/d51fbab4b32d56765e8faab6ad01245fb259b0ca
  TheCharlatan:
    Re-ACK d51fbab4b32d56765e8faab6ad01245fb259b0ca
  furszy:
    reACK d51fbab4b32d56765e8faab6ad01245fb259b0ca
  laanwj:
    re-ACK d51fbab4b32d56765e8faab6ad01245fb259b0ca
  theStack:
    ACK d51fbab4b32d56765e8faab6ad01245fb259b0ca

Tree-SHA512: 1e7b97edf223b2974eed2e9eac1179fc82bb6359e0a66b7d2a0c8b9fa515eae9ea036f1edf7c76cdab2e75ad994962b134b41056ccfbc33b8d54f0859e86657b

1 files changed, 34 insertions, 6 deletions

diff --git a/src/wallet/test/db_tests.cpp b/src/wallet/test/db_tests.cpp
index 438dfceb7f..2fac356263 100644
--- a/src/wallet/test/db_tests.cpp
+++ b/src/wallet/test/db_tests.cpp
@@ -16,6 +16,7 @@
 #ifdef USE_SQLITE
 #include <wallet/sqlite.h>
 #endif
+#include <wallet/migrate.h>
 #include <wallet/test/util.h>
 #include <wallet/walletutil.h> // for WALLET_FLAG_DESCRIPTORS
 
@@ -132,6 +133,8 @@ static std::vector<std::unique_ptr<WalletDatabase>> TestDatabases(const fs::path
     bilingual_str error;
 #ifdef USE_BDB
     dbs.emplace_back(MakeBerkeleyDatabase(path_root / "bdb", options, status, error));
+    // Needs BDB to make the DB to read
+    dbs.emplace_back(std::make_unique<BerkeleyRODatabase>(BDBDataFile(path_root / "bdb"), /*open=*/false));
 #endif
 #ifdef USE_SQLITE
     dbs.emplace_back(MakeSQLiteDatabase(path_root / "sqlite", options, status, error));
@@ -146,11 +149,16 @@ BOOST_AUTO_TEST_CASE(db_cursor_prefix_range_test)
     for (const auto& database : TestDatabases(m_path_root)) {
         std::vector<std::string> prefixes = {"", "FIRST", "SECOND", "P\xfe\xff", "P\xff\x01", "\xff\xff"};
 
-        // Write elements to it
         std::unique_ptr<DatabaseBatch> handler = Assert(database)->MakeBatch();
-        for (unsigned int i = 0; i < 10; i++) {
-            for (const auto& prefix : prefixes) {
-                BOOST_CHECK(handler->Write(std::make_pair(prefix, i), i));
+        if (dynamic_cast<BerkeleyRODatabase*>(database.get())) {
+            // For BerkeleyRO, open the file now. This must happen after BDB has written to the file
+            database->Open();
+        } else {
+            // Write elements to it if not berkeleyro
+            for (unsigned int i = 0; i < 10; i++) {
+                for (const auto& prefix : prefixes) {
+                    BOOST_CHECK(handler->Write(std::make_pair(prefix, i), i));
+                }
             }
         }
 
@@ -178,6 +186,8 @@ BOOST_AUTO_TEST_CASE(db_cursor_prefix_range_test)
             // Let's now read it once more, it should return DONE
             BOOST_CHECK(cursor->Next(key, value) == DatabaseCursor::Status::DONE);
         }
+        handler.reset();
+        database->Close();
     }
 }
 
@@ -197,13 +207,23 @@ BOOST_AUTO_TEST_CASE(db_cursor_prefix_byte_test)
         ffs{StringData("\xff\xffsuffix"), StringData("ffs")};
     for (const auto& database : TestDatabases(m_path_root)) {
         std::unique_ptr<DatabaseBatch> batch = database->MakeBatch();
-        for (const auto& [k, v] : {e, p, ps, f, fs, ff, ffs}) {
-            batch->Write(Span{k}, Span{v});
+
+        if (dynamic_cast<BerkeleyRODatabase*>(database.get())) {
+            // For BerkeleyRO, open the file now. This must happen after BDB has written to the file
+            database->Open();
+        } else {
+            // Write elements to it if not berkeleyro
+            for (const auto& [k, v] : {e, p, ps, f, fs, ff, ffs}) {
+                batch->Write(Span{k}, Span{v});
+            }
         }
+
         CheckPrefix(*batch, StringBytes(""), {e, p, ps, f, fs, ff, ffs});
         CheckPrefix(*batch, StringBytes("prefix"), {p, ps});
         CheckPrefix(*batch, StringBytes("\xff"), {f, fs, ff, ffs});
         CheckPrefix(*batch, StringBytes("\xff\xff"), {ff, ffs});
+        batch.reset();
+        database->Close();
     }
 }
 
@@ -213,6 +233,10 @@ BOOST_AUTO_TEST_CASE(db_availability_after_write_error)
     // To simulate the behavior, record overwrites are disallowed, and the test verifies
     // that the database remains active after failing to store an existing record.
     for (const auto& database : TestDatabases(m_path_root)) {
+        if (dynamic_cast<BerkeleyRODatabase*>(database.get())) {
+            // Skip this test if BerkeleyRO
+            continue;
+        }
         // Write original record
         std::unique_ptr<DatabaseBatch> batch = database->MakeBatch();
         std::string key = "key";
@@ -241,6 +265,10 @@ BOOST_AUTO_TEST_CASE(erase_prefix)
     auto make_key = [](std::string type, std::string id) { return std::make_pair(type, id); };
 
     for (const auto& database : TestDatabases(m_path_root)) {
+        if (dynamic_cast<BerkeleyRODatabase*>(database.get())) {
+            // Skip this test if BerkeleyRO
+            continue;
+        }
         std::unique_ptr<DatabaseBatch> batch = database->MakeBatch();
 
         // Write two entries with the same key type prefix, a third one with a different prefix