vapi: support api clients within vpp process

Add vapi_connect_from_vpp() and vapi_disconnect_from_vpp()
calls to allow API clients from within VPP process.

Add a new memclnt_create version that gives the user a
knob to enable or disable dead client scans (keepalive).

Type: feature
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: Id0b7bb89308db3a3aed2d3fcbedf4e1282dcd03f
Signed-off-by: Ole Troan <ot@cisco.com>

1 files changed, 101 insertions, 0 deletions

diff --git a/src/plugins/unittest/api_test.c b/src/plugins/unittest/api_test.c
new file mode 100644
index 00000000000..4bed50c2969
--- /dev/null
+++ b/src/plugins/unittest/api_test.c
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright(c) 2022 Cisco Systems, Inc.
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/plugin/plugin.h>
+
+#include <vlibapi/api.h>
+#include <vlibmemory/api.h>
+#include <vpp/app/version.h>
+#include <stdbool.h>
+#include <vapi/vapi.h>
+
+#include <vapi/memclnt.api.vapi.h>
+#include <vapi/vlib.api.vapi.h>
+#include <vapi/vpe.api.vapi.h>
+
+/*
+ * Example of how to call the VPP binary API from an internal API client.
+ * Using the VAPI C language binding.
+ */
+
+DEFINE_VAPI_MSG_IDS_VPE_API_JSON;
+
+/*
+ * Connect an VPP binary API client to VPP API
+ */
+static vapi_ctx_t
+connect_to_vpp (void)
+{
+  vapi_ctx_t ctx;
+  if (vapi_ctx_alloc (&ctx) != VAPI_OK)
+    {
+      clib_warning ("ctx_alloc failed");
+      return 0;
+    }
+  if (vapi_connect_from_vpp (ctx, "apifromplugin", 64, 32, VAPI_MODE_BLOCKING,
+			     true) != VAPI_OK)
+    {
+      clib_warning ("vapi_connect failed");
+      return 0;
+    }
+  return ctx;
+}
+
+/*
+ * Gets called when the show_version_reply message is received
+ */
+vapi_error_e
+show_version_cb (vapi_ctx_t ctx, void *caller_ctx, vapi_error_e rv,
+		 bool is_last, vapi_payload_show_version_reply *p)
+{
+  if (rv != VAPI_OK)
+    clib_warning ("Return value: %d", rv);
+  fformat (
+    stdout,
+    "show_version_reply: program: `%s', version: `%s', build directory: "
+    "`%s', build date: `%s'\n",
+    p->program, p->version, p->build_directory, p->build_date);
+  return VAPI_OK;
+}
+
+static void *
+api_show_version_blocking_fn (void *args)
+{
+  vapi_ctx_t ctx;
+
+  if ((ctx = connect_to_vpp ()) == 0)
+    return clib_error_return (0, "API connection failed");
+
+  int called;
+  vapi_msg_show_version *sv = vapi_alloc_show_version (ctx);
+  vapi_error_e vapi_rv = vapi_show_version (ctx, sv, show_version_cb, &called);
+  if (vapi_rv != VAPI_OK)
+    clib_warning ("call failed");
+
+  vapi_disconnect_from_vpp (ctx);
+  vapi_ctx_free (ctx);
+
+  return 0;
+}
+
+static clib_error_t *
+test_api_test_command_fn (vlib_main_t *vm, unformat_input_t *input,
+			  vlib_cli_command_t *cmd)
+{
+  /* Run call in a pthread */
+  pthread_t thread;
+  int rv = pthread_create (&thread, NULL, api_show_version_blocking_fn, 0);
+  if (rv)
+    {
+      return clib_error_return (0, "API call failed");
+    }
+  return 0;
+}
+
+VLIB_CLI_COMMAND (test_api_command, static) = {
+  .path = "test api internal",
+  .short_help = "test internal api client",
+  .function = test_api_test_command_fn,
+};