From 32828e03be0489572ab334239c5768c86697989f Mon Sep 17 00:00:00 2001
From: Fedor Indutnyy <indutny@signal.org>
Date: Wed, 20 Oct 2021 11:32:50 -0700
Subject: [PATCH] Log corruption error information

---
 lib/database.js        |  2 ++
 src/better_sqlite3.cpp | 43 ++++++++++++++++++++++++++++++++++++++++++
 src/better_sqlite3.hpp |  1 +
 3 files changed, 46 insertions(+)

diff --git a/lib/database.js b/lib/database.js
index 8c437c64..8daa4b86 100644
--- a/lib/database.js
+++ b/lib/database.js
@@ -6,6 +6,7 @@ const util = require('./util');
 const {
 	Database: CPPDatabase,
 	setErrorConstructor,
+	setCorruptionLogger,
 } = require('bindings')('better_sqlite3.node');
 
 function Database(filenameGiven, options) {
@@ -61,6 +62,7 @@ Database.prototype.close = wrappers.close;
 Database.prototype.defaultSafeIntegers = wrappers.defaultSafeIntegers;
 Database.prototype.unsafeMode = wrappers.unsafeMode;
 Database.prototype[util.inspect] = require('./methods/inspect');
+Database.setCorruptionLogger = setCorruptionLogger;
 
 module.exports = Database;
 setErrorConstructor(require('./sqlite-error'));
diff --git a/src/better_sqlite3.cpp b/src/better_sqlite3.cpp
index c1d1e45d..138adaff 100644
--- a/src/better_sqlite3.cpp
+++ b/src/better_sqlite3.cpp
@@ -18,6 +18,7 @@ NODE_MODULE_INIT(/* exports, context */) {
 	exports->Set(context, InternalizedFromLatin1(isolate, "StatementIterator"), StatementIterator::Init(isolate, data)).FromJust();
 	exports->Set(context, InternalizedFromLatin1(isolate, "Backup"), Backup::Init(isolate, data)).FromJust();
 	exports->Set(context, InternalizedFromLatin1(isolate, "setErrorConstructor"), v8::FunctionTemplate::New(isolate, Addon::JS_setErrorConstructor, data)->GetFunction(context).ToLocalChecked()).FromJust();
+	exports->Set(context, InternalizedFromLatin1(isolate, "setCorruptionLogger"), v8::FunctionTemplate::New(isolate, Addon::JS_setCorruptionLogger, data)->GetFunction(context).ToLocalChecked()).FromJust();
 
 	// Store addon instance data.
 	addon->Statement.Reset(isolate, v8::Local<v8::Function>::Cast(exports->Get(context, InternalizedFromLatin1(isolate, "Statement")).ToLocalChecked()));
@@ -1669,6 +1670,48 @@ void Addon::JS_setErrorConstructor (v8::FunctionCallbackInfo <v8 :: Value> const
                 if ( info . Length ( ) <= ( 0 ) || ! info [ 0 ] -> IsFunction ( ) ) return ThrowTypeError ( "Expected " "first" " argument to be " "a function" ) ; v8 :: Local < v8 :: Function > SqliteError = v8 :: Local < v8 :: Function > :: Cast ( info [ 0 ] ) ;
                 static_cast < Addon * > ( v8 :: Local < v8 :: External > :: Cast ( info . Data ( ) ) -> Value ( ) ) ->SqliteError.Reset( info . GetIsolate ( ) , SqliteError);
 }
+
+class LogWrapper {
+ public:
+  LogWrapper(
+      v8::Isolate* isolate,
+      v8::Local<v8::Function> fn
+  ): isolate_(isolate) {
+    fn_.Reset(isolate, fn);
+  }
+
+  void Call(const char* msg) {
+    v8::HandleScope scope(isolate_);
+    v8::Local<v8::Function> fn =
+      v8::Local<v8::Function>::New(isolate_, fn_);
+    v8::Local<v8::Value> arg = StringFromUtf8(isolate_, msg, -1);
+    fn->Call(isolate_->GetCurrentContext(), v8::Undefined(isolate_), 1, &arg);
+  }
+
+  static void Fn(void *pArg, int iErrCode, const char *zMsg) {
+    LogWrapper* wrapper = reinterpret_cast<LogWrapper*>(pArg);
+    if (iErrCode == SQLITE_CORRUPT || iErrCode == SQLITE_NOTADB) {
+      wrapper->Call(zMsg);
+    }
+  }
+
+ private:
+  v8::Isolate* isolate_;
+  v8::Persistent<v8::Function> fn_;
+};
+
+void Addon::JS_setCorruptionLogger (v8::FunctionCallbackInfo <v8 :: Value> const & info) {
+  if (info.Length() <= 0)
+    return ThrowTypeError("Expected one argument");
+
+  v8::Local<v8::Function> fn = v8::Local<v8::Function>::Cast(info[0]);
+  int status = sqlite3_config(
+      SQLITE_CONFIG_LOG,
+      LogWrapper::Fn,
+      new LogWrapper(v8::Isolate::GetCurrent(), fn));
+  assert(status == SQLITE_OK);
+}
+
 #line 48 "./src/better_sqlite3.lzz"
 void Addon::Cleanup (void * ptr)
 #line 48 "./src/better_sqlite3.lzz"
diff --git a/src/better_sqlite3.hpp b/src/better_sqlite3.hpp
index 37bf6699..54468c9c 100644
--- a/src/better_sqlite3.hpp
+++ b/src/better_sqlite3.hpp
@@ -665,6 +665,7 @@ struct Addon
   std::set <Database*, Database::CompareDatabase> dbs;
 #line 43 "./src/better_sqlite3.lzz"
   static void JS_setErrorConstructor (v8::FunctionCallbackInfo <v8 :: Value> const & info);
+  static void JS_setCorruptionLogger (v8::FunctionCallbackInfo <v8 :: Value> const & info);
 #line 48 "./src/better_sqlite3.lzz"
   static void Cleanup (void * ptr);
 #line 55 "./src/better_sqlite3.lzz"