Implement receive thread for IPC client

include/ggl/attr.h

@@ -96,6 +96,16 @@
 #define NULL_TERMINATED_STRING_ARG(pos)
 #endif
 
+#ifdef __has_attribute
+#if __has_attribute(access)
+#define ACCESS(...) __attribute__((access(__VA_ARGS__)))
+#endif
+#endif
+
+#ifndef ACCESS
+#define ACCESS(...)
+#endif
+
 #ifdef __has_attribute
 #if __has_attribute(cold)
 #define COLD __attribute__((cold))
@@ -116,4 +126,14 @@
 #define CONST
 #endif
 
+#ifdef __has_attribute
+#if __has_attribute(flag_enum)
+#define FLAG_ENUM __attribute__((flag_enum))
+#endif
+#endif
+
+#ifndef FLAG_ENUM
+#define FLAG_ENUM
+#endif
+
 #endif

include/ggl/error.h

@@ -43,6 +43,8 @@ typedef enum NODISCARD GglError {
     GGL_ERR_REMOTE,
     /// Expected non-ok status
     GGL_ERR_EXPECTED,
+    /// Request timed out
+    GGL_ERR_TIMEOUT,
 } GglError;
 
 const char *ggl_strerror(GglError err);

include/ggl/ipc/client.h

@@ -6,7 +6,6 @@
 #define GGL_IPC_CLIENT_H
 
 #include <ggl/arena.h>
-#include <ggl/attr.h>
 #include <ggl/buffer.h>
 #include <ggl/error.h>
 #include <ggl/ipc/error.h>
@@ -18,13 +17,6 @@ struct timespec;
 
 #define GGL_IPC_SVCUID_STR_LEN (16)
 
-/// Connect to GG-IPC server using component name.
-/// If svcuid is non-null, it will be filled with the component's identity
-/// token. Buffer must be able to hold at least GGL_IPC_SVCUID_STR_LEN.
-GglError ggipc_connect_by_name(
-    GglBuffer socket_path, GglBuffer component_name, int *fd, GglBuffer *svcuid
-) NONNULL(3);
-
 GglError ggipc_call(
     int conn,
     GglBuffer operation,
@@ -35,10 +27,6 @@ GglError ggipc_call(
     GglIpcError *remote_err
 );
 
-GglError ggipc_private_get_system_config(
-    int conn, GglBuffer key, GglBuffer *value
-);
-
 GglError ggipc_get_config_str(
     int conn, GglBufList key_path, GglBuffer *component_name, GglBuffer *value
 );

include/ggl/sdk.h

@@ -0,0 +1,13 @@
+// aws-greengrass-sdk-lite - Lightweight AWS IoT Greengrass SDK
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef GGL_SDK_H
+#define GGL_SDK_H
+
+/// Initializes the sdk, including starting necessary threads.
+/// Unused portions of sdk may not be initialized.
+/// Exits on error.
+void ggl_sdk_init(void);
+
+#endif

priv_include/ggl/eventstream/rpc.h

@@ -21,7 +21,7 @@ typedef enum {
 } EventStreamMessageType;
 
 /// `:message-flags` header flags
-typedef enum {
+typedef enum FLAG_ENUM {
     EVENTSTREAM_CONNECTION_ACCEPTED = 1,
     EVENTSTREAM_TERMINATE_STREAM = 2,
 } EventStreamMessageFlags;

priv_include/ggl/init.h

@@ -0,0 +1,21 @@
+// aws-greengrass-sdk-lite - Lightweight AWS IoT Greengrass SDK
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef GGL_INIT_H
+#define GGL_INIT_H
+
+#include <ggl/attr.h>
+#include <ggl/error.h>
+
+typedef struct GglInitEntry {
+    GglError (*fn)(void);
+    struct GglInitEntry *next;
+} GglInitEntry;
+
+/// Initializes the sdk, including starting necessary threads.
+/// Unused portions of sdk may not be initialized.
+/// Not thread-safe
+void ggl_register_init_fn(GglInitEntry *entry) NONNULL(1);
+
+#endif

priv_include/ggl/ipc/client_priv.h

@@ -8,13 +8,27 @@
 #include <ggl/attr.h>
 #include <ggl/buffer.h>
 #include <ggl/error.h>
-#include <ggl/object.h>
 
-/// Connect to GG-IPC server with the given payload.
+/// Maximum size of eventstream packet.
+/// Can be configured with `-D GGL_IPC_MAX_MSG_LEN=<N>`.
+#ifndef GGL_IPC_MAX_MSG_LEN
+#define GGL_IPC_MAX_MSG_LEN 10000
+#endif
+
+/// Maximum size IPC functions will wait for server response
+#ifndef GGL_IPC_RESPONSE_TIMEOUT
+#define GGL_IPC_RESPONSE_TIMEOUT 10
+#endif
+
+/// Connect to GG-IPC server using component name.
 /// If svcuid is non-null, it will be filled with the component's identity
 /// token. Buffer must be able to hold at least GGL_IPC_SVCUID_STR_LEN.
-GglError ggipc_connect_with_payload(
-    GglBuffer socket_path, GglMap payload, int *fd, GglBuffer *svcuid
+GglError ggipc_connect_by_name(
+    GglBuffer socket_path, GglBuffer component_name, int *fd, GglBuffer *svcuid
 ) NONNULL(3);
 
+GglError ggipc_private_get_system_config(
+    int conn, GglBuffer key, GglBuffer *value
+);
+
 #endif

src/buffer.c

@@ -18,6 +18,9 @@ GglBuffer ggl_buffer_from_null_term(char *str) {
 
 bool ggl_buffer_eq(GglBuffer buf1, GglBuffer buf2) {
     if (buf1.len == buf2.len) {
+        if (buf1.len == 0) {
+            return true;
+        }
         return memcmp(buf1.data, buf2.data, buf1.len) == 0;
     }
     return false;

src/error.c

@@ -40,6 +40,8 @@ const char *ggl_strerror(GglError err) {
         return "REMOTE";
     case GGL_ERR_EXPECTED:
         return "EXPECTED";
+    case GGL_ERR_TIMEOUT:
+        return "TIMEOUT";
     }
 
     assert(false);

src/init.c

@@ -0,0 +1,31 @@
+// aws-greengrass-sdk-lite - Lightweight AWS IoT Greengrass SDK
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+#include <ggl/error.h>
+#include <ggl/init.h>
+#include <ggl/log.h>
+#include <ggl/sdk.h>
+#include <stdlib.h>
+
+static GglInitEntry *init_list = NULL;
+
+void ggl_register_init_fn(GglInitEntry *entry) {
+    entry->next = init_list;
+    init_list = entry;
+}
+
+void ggl_sdk_init(void) {
+    GglInitEntry *list = init_list;
+    init_list = NULL;
+
+    while (list != NULL) {
+        GglError ret = list->fn();
+        if (ret != GGL_ERR_OK) {
+            GGL_LOGE("Failed to initialize (%u).", (unsigned) ret);
+            _Exit(1);
+        }
+
+        list = list->next;
+    }
+}