From bac9e3483637357dedf3374d7449ac705eb41c8e Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Thu, 26 Oct 2023 18:06:56 +0300
Subject: [PATCH] Allow to create vitastor_c with plain epoll without uring :-)

---
 src/vitastor_c.cpp | 26 +++++++++++++++++++++++++-
 src/vitastor_c.h   |  5 ++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/src/vitastor_c.cpp b/src/vitastor_c.cpp
index 6e23bf49..a7397b35 100644
--- a/src/vitastor_c.cpp
+++ b/src/vitastor_c.cpp
@@ -186,12 +186,26 @@ vitastor_c *vitastor_c_create_uring_json(const char **options, int options_len)
     return self;
 }
 
+vitastor_c *vitastor_c_create_epoll_json(const char **options, int options_len)
+{
+    json11::Json::object cfg;
+    for (int i = 0; i < options_len-1; i += 2)
+    {
+        cfg[options[i]] = std::string(options[i+1]);
+    }
+    json11::Json cfg_json(cfg);
+    vitastor_c *self = new vitastor_c;
+    self->epmgr = new epoll_manager_t(NULL);
+    self->cli = new cluster_client_t(NULL, self->epmgr->tfd, cfg_json);
+    return self;
+}
+
 void vitastor_c_destroy(vitastor_c *client)
 {
     delete client->cli;
     if (client->epmgr)
         delete client->epmgr;
-    else
+    else if (client->tfd)
         delete client->tfd;
     if (client->ringloop)
         delete client->ringloop;
@@ -229,6 +243,16 @@ int vitastor_c_uring_has_work(vitastor_c *client)
     return client->ringloop->has_work();
 }
 
+int vitastor_c_epoll_get_fd(vitastor_c *client)
+{
+    return !client->ringloop && client->epmgr ? client->epmgr->get_fd() : -1;
+}
+
+void vitastor_c_epoll_handle_events(vitastor_c *client, int timeout)
+{
+    return client->epmgr->handle_events(timeout);
+}
+
 void vitastor_c_read(vitastor_c *client, uint64_t inode, uint64_t offset, uint64_t len,
     struct iovec *iov, int iovcnt, VitastorReadHandler cb, void *opaque)
 {
diff --git a/src/vitastor_c.h b/src/vitastor_c.h
index 5cd8e8a4..258fdf85 100644
--- a/src/vitastor_c.h
+++ b/src/vitastor_c.h
@@ -7,7 +7,7 @@
 #define VITASTOR_QEMU_PROXY_H
 
 // C API wrapper version
-#define VITASTOR_C_API_VERSION 2
+#define VITASTOR_C_API_VERSION 3
 
 #ifndef POOL_ID_BITS
 #define POOL_ID_BITS 16
@@ -40,6 +40,7 @@ vitastor_c *vitastor_c_create_qemu_uring(QEMUSetFDHandler *aio_set_fd_handler, v
 vitastor_c *vitastor_c_create_uring(const char *config_path, const char *etcd_host, const char *etcd_prefix,
     int use_rdma, const char *rdma_device, int rdma_port_num, int rdma_gid_index, int rdma_mtu, int log_level);
 vitastor_c *vitastor_c_create_uring_json(const char **options, int options_len);
+vitastor_c *vitastor_c_create_epoll_json(const char **options, int options_len);
 void vitastor_c_destroy(vitastor_c *client);
 int vitastor_c_is_ready(vitastor_c *client);
 int vitastor_c_uring_register_eventfd(vitastor_c *client);
@@ -47,6 +48,8 @@ void vitastor_c_uring_wait_ready(vitastor_c *client);
 void vitastor_c_uring_handle_events(vitastor_c *client);
 void vitastor_c_uring_wait_events(vitastor_c *client);
 int vitastor_c_uring_has_work(vitastor_c *client);
+int vitastor_c_epoll_get_fd(vitastor_c *client);
+void vitastor_c_epoll_handle_events(vitastor_c *client, int timeout);
 void vitastor_c_read(vitastor_c *client, uint64_t inode, uint64_t offset, uint64_t len,
     struct iovec *iov, int iovcnt, VitastorReadHandler cb, void *opaque);
 void vitastor_c_write(vitastor_c *client, uint64_t inode, uint64_t offset, uint64_t len, uint64_t check_version,