Merge branch 'cbindgen-ci' into 'main'

Test cbindgen correctness in CI

Closes #1502

See merge request tpo/core/arti!2320

.gitlab-ci.yml

@@ -99,6 +99,15 @@ maint-check-ownership:
     # a chance to run `cargo add`.
     - if: $CI_COMMIT_BRANCH == "main"
 
+maint-check-cbindgen:
+  stage: test
+  # cbindgen needs nightly rust to do macro expansion
+  image: rustlang/rust:nightly
+  script:
+    - ./maint/common/apt-install python3-toml
+    - ./maint/common/via-cargo-install-in-ci cbindgen
+    - ./maint/cbindgen --check
+
 # non-blocking for now, see
 #      https://gitlab.torproject.org/tpo/core/arti/-/issues/581
 #      https://gitlab.torproject.org/tpo/core/arti/-/issues/601

crates/arti-rpc-client-core/arti-rpc-client-core.h

@@ -296,6 +296,22 @@ ArtiRpcStatus arti_rpc_connect(const char *connection_string,
                                ArtiRpcConn **rpc_conn_out,
                                ArtiRpcError **error_out);
 
+/**
+ * Given a pointer to an RPC connection, return the object ID for its negotiated session.
+ *
+ * (The session was negotiated as part of establishing the connection.
+ * Its object ID is necessary to invoke most other functionality on Arti.)
+ *
+ * The caller should be prepared for a possible NULL return, in case somehow
+ * no session was negotiated.
+ *
+ * # Ownership
+ *
+ * The resulting string is a reference to part of the `ArtiRpcConn`.
+ * It lives for no longer than the underlying `ArtiRpcConn` object.
+ */
+const char *arti_rpc_conn_get_session_id(const ArtiRpcConn *rpc_conn);
+
 /**
  * Run an RPC request over `rpc_conn` and wait for a successful response.
  *
@@ -356,6 +372,18 @@ const char *arti_status_to_str(ArtiRpcStatus status);
  */
 ArtiRpcStatus arti_rpc_err_status(const ArtiRpcError *err);
 
+/**
+ * Return the OS error code underlying `err`, if any.
+ *
+ * This is typically an `errno` on unix-like systems , or the result of `GetLastError()`
+ * on Windows.  It is only present when `err` was caused by the failure of some
+ * OS library call, like a `connect()` or `read()`.
+ *
+ * Returns 0 if `err` is NULL, or if `err` was not caused by the failure of an
+ * OS library call.
+ */
+int arti_rpc_err_os_error_code(const ArtiRpcError *err);
+
 /**
  * Return a human-readable error message associated with a given error.
  *

crates/arti-rpc-client-core/cbindgen.warnings

@@ -15,6 +15,9 @@ WARN: Skip arti-rpc-client-core::_ - (not `pub`).
 WARN: Skip arti-rpc-client-core::_ - (not `pub`).
 WARN: Skip arti-rpc-client-core::_ - (not `pub`).
 WARN: Skip arti-rpc-client-core::_ - (not `pub`).
+WARN: Skip arti-rpc-client-core::_ - (not `pub`).
+WARN: Skip arti-rpc-client-core::_ - (not `pub`).
+WARN: Skip arti-rpc-client-core::_ - (not `pub`).
 WARN: Cannot find a mangling for generic path GenericPath { path: Path { name: "Map" }, export_name: "Map", generics: [Type(Path(GenericPath { path: Path { name: "String" }, export_name: "String", generics: [], ctype: None })), Type(Path(GenericPath { path: Path { name: "Value" }, export_name: "Value", generics: [], ctype: None }))], ctype: None }. This usually means that a type referenced by this generic was incompatible or not found.
 WARN: Can't find RpcConn. This usually means that this type was incompatible or not found.
 WARN: Can't find FfiError. This usually means that this type was incompatible or not found.
@@ -50,3 +53,5 @@ WARN: Missing `[defines]` entry for `feature = "ffi"` in cbindgen config.
 WARN: Missing `[defines]` entry for `feature = "ffi"` in cbindgen config.
 WARN: Missing `[defines]` entry for `feature = "ffi"` in cbindgen config.
 WARN: Missing `[defines]` entry for `feature = "ffi"` in cbindgen config.
+WARN: Missing `[defines]` entry for `feature = "ffi"` in cbindgen config.
+WARN: Missing `[defines]` entry for `feature = "ffi"` in cbindgen config.

maint/cbindgen

@@ -71,7 +71,7 @@ while true; do
 	    shift
 	    ;;
 	-c | --check)
-	    fail_on_change=0
+	    fail_on_change=1
 	    replace=0
 	    shift
 	    ;;