From f207523421b22d0eddbb68faa4275c41de77600f Mon Sep 17 00:00:00 2001
From: canepat <16927169+canepat@users.noreply.github.com>
Date: Wed, 18 Oct 2023 22:25:04 +0200
Subject: [PATCH] api: handle RPCDaemon not started or already started (#1591)

---
 silkworm/api/silkworm_api.cpp |  9 ++++++++-
 silkworm/api/silkworm_api.h   | 23 +++++++++++++----------
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/silkworm/api/silkworm_api.cpp b/silkworm/api/silkworm_api.cpp
index b2aad21b19..758b63bb71 100644
--- a/silkworm/api/silkworm_api.cpp
+++ b/silkworm/api/silkworm_api.cpp
@@ -277,6 +277,9 @@ SILKWORM_EXPORT int silkworm_start_rpcdaemon(SilkwormHandle* handle, MDBX_env* e
     if (handle != instance.handle) {
         return SILKWORM_INSTANCE_NOT_FOUND;
     }
+    if (instance.rpcdaemon) {
+        return SILKWORM_RPCDAEMON_ALREADY_STARTED;
+    }
 
     struct EnvUnmanaged : public ::mdbx::env {
         explicit EnvUnmanaged(MDBX_env* ptr) : ::mdbx::env{ptr} {}
@@ -293,7 +296,7 @@ SILKWORM_EXPORT int silkworm_start_rpcdaemon(SilkwormHandle* handle, MDBX_env* e
     instance.rpcdaemon = std::make_unique<rpc::Daemon>(settings, std::make_optional<mdbx::env>(unmanaged_env));
 
     // Check protocol version compatibility with Core Services
-    if (not settings.skip_protocol_check) {
+    if (!settings.skip_protocol_check) {
         SILK_INFO << "[Silkworm RPC] Checking protocol version compatibility with core services...";
 
         const auto checklist = instance.rpcdaemon->run_checklist();
@@ -315,11 +318,15 @@ SILKWORM_EXPORT int silkworm_stop_rpcdaemon(SilkwormHandle* handle) SILKWORM_NOE
     if (handle != instance.handle) {
         return SILKWORM_INSTANCE_NOT_FOUND;
     }
+    if (!instance.rpcdaemon) {
+        return SILKWORM_RPCDAEMON_NOT_STARTED;
+    }
 
     instance.rpcdaemon->stop();
     SILK_INFO << "[Silkworm RPC] Exiting...";
     instance.rpcdaemon->join();
     SILK_INFO << "[Silkworm RPC] Stopped";
+    instance.rpcdaemon.reset();
 
     return SILKWORM_OK;
 }
diff --git a/silkworm/api/silkworm_api.h b/silkworm/api/silkworm_api.h
index b79a7e2960..184f3c4939 100644
--- a/silkworm/api/silkworm_api.h
+++ b/silkworm/api/silkworm_api.h
@@ -39,10 +39,9 @@
 extern "C" {
 #endif
 
-typedef struct MDBX_env MDBX_env;
-typedef struct MDBX_txn MDBX_txn;
+// Silkworm library error codes (SILKWORM_OK indicates no error, i.e. success)
 
-#define SILKWORM_OK 0 /* Successful result */
+#define SILKWORM_OK 0
 #define SILKWORM_INTERNAL_ERROR 1
 #define SILKWORM_UNKNOWN_ERROR 2
 #define SILKWORM_INVALID_HANDLE 3
@@ -58,16 +57,13 @@ typedef struct MDBX_txn MDBX_txn;
 #define SILKWORM_TOO_MANY_INSTANCES 13
 #define SILKWORM_INSTANCE_NOT_FOUND 14
 #define SILKWORM_TERMINATION_SIGNAL 15
+#define SILKWORM_RPCDAEMON_ALREADY_STARTED 16
+#define SILKWORM_RPCDAEMON_NOT_STARTED 17
 
+typedef struct MDBX_env MDBX_env;
+typedef struct MDBX_txn MDBX_txn;
 typedef struct SilkwormHandle SilkwormHandle;
 
-/**
- * \brief Initialize the Silkworm C API library.
- * \param[in,out] handle Silkworm instance handle returned on successful initialization.
- * \return SILKWORM_OK (=0) on success, a non-zero error value on failure.
- */
-SILKWORM_EXPORT int silkworm_init(SilkwormHandle** handle) SILKWORM_NOEXCEPT;
-
 struct SilkwormMemoryMappedFile {
     const char* file_path;
     uint8_t* memory_address;
@@ -96,6 +92,13 @@ struct SilkwormChainSnapshot {
     struct SilkwormTransactionsSnapshot transactions;
 };
 
+/**
+ * \brief Initialize the Silkworm C API library.
+ * \param[in,out] handle Silkworm instance handle returned on successful initialization.
+ * \return SILKWORM_OK (=0) on success, a non-zero error value on failure.
+ */
+SILKWORM_EXPORT int silkworm_init(SilkwormHandle** handle) SILKWORM_NOEXCEPT;
+
 /**
  * \brief Build a set of indexes for the given snapshots.
  * \param[in] handle A valid Silkworm instance handle, got with silkworm_init.