Stubs fallback

src/bindings/rust/Cargo.toml

@@ -40,6 +40,7 @@ bindgen = "0.71"
 cc = { version = "1.2.23", features = ["parallel"] }
 pkg-config = "0.3"
 os_info = "3.11"
+anyhow = "1"
 
 [dev-dependencies]
 tempfile = "3.20.0"

src/bindings/rust/build.rs

@@ -13,9 +13,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use os_info;
 use std::env;
 use std::path::PathBuf;
-use os_info;
 
 fn get_lib_path(nixl_root_path: &str, arch: &str) -> String {
     let os_info = os_info::get();
@@ -77,14 +77,30 @@ fn get_nixl_libs() -> Option<Vec<pkg_config::Library>> {
         pkg_config::probe_library("etcd-cpp-api"),
         pkg_config::probe_library("ucx"),
     ) {
-        (Ok(nixl), Ok(nixl_build), Ok(nixl_common), Ok(stream), Ok(serdes), Ok(ucx_utils), Ok(etcd), Ok(ucx)) => {
-            Some(vec![nixl, nixl_build, nixl_common, stream, serdes, ucx_utils, etcd, ucx])
-        }
+        (
+            Ok(nixl),
+            Ok(nixl_build),
+            Ok(nixl_common),
+            Ok(stream),
+            Ok(serdes),
+            Ok(ucx_utils),
+            Ok(etcd),
+            Ok(ucx),
+        ) => Some(vec![
+            nixl,
+            nixl_build,
+            nixl_common,
+            stream,
+            serdes,
+            ucx_utils,
+            etcd,
+            ucx,
+        ]),
         _ => None,
     }
 }
 
-fn build_nixl(cc_builder: &mut cc::Build) {
+fn build_nixl(cc_builder: &mut cc::Build) -> anyhow::Result<()> {
     let nixl_root_path =
         env::var("NIXL_PREFIX").unwrap_or_else(|_| "/opt/nvidia/nvda_nixl".to_string());
 
@@ -94,7 +110,7 @@ fn build_nixl(cc_builder: &mut cc::Build) {
     let nixl_include_path = format!("{}/include", nixl_root_path);
     let nixl_include_paths = [
         &nixl_include_path,
-        "../../api/cpp",
+        //"../../api/cpp",
         "../../infra",
         "../../core",
         "/usr/include",
@@ -111,7 +127,10 @@ fn build_nixl(cc_builder: &mut cc::Build) {
     println!("cargo:rustc-link-search=native={}", nixl_root_path);
     println!("cargo:rustc-link-search=native={}/lib", nixl_root_path);
     println!("cargo:rustc-link-search=native={}/lib64", nixl_root_path);
-    println!("cargo:rustc-link-search=native={}/lib/x86_64-linux-gnu", nixl_root_path);
+    println!(
+        "cargo:rustc-link-search=native={}/lib/x86_64-linux-gnu",
+        nixl_root_path
+    );
 
     // Try to use pkg-config if available
     if let Some(libs) = get_nixl_libs() {
@@ -125,10 +144,7 @@ fn build_nixl(cc_builder: &mut cc::Build) {
         println!("cargo:warning=pkg-config not available, using manual library paths");
     }
 
-    cc_builder
-        .file("wrapper.cpp")
-        .includes(nixl_include_paths);
-
+    cc_builder.file("wrapper.cpp").includes(nixl_include_paths);
 
     println!("cargo:rustc-link-search={}", nixl_lib_path);
 
@@ -139,10 +155,10 @@ fn build_nixl(cc_builder: &mut cc::Build) {
     }
 
     // Compile the wrapper C++ code
-    cc_builder.compile("nixl_wrapper");
+    cc_builder.try_compile("nixl_wrapper")?;
 
     // Get the output path for bindings
-    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    let out_path = PathBuf::from(env::var("OUT_DIR")?);
 
     // Generate bindings with minimal configuration
     let mut builder = bindgen::Builder::default()
@@ -183,9 +199,10 @@ fn build_nixl(cc_builder: &mut cc::Build) {
     builder
         .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
         .generate()
-        .expect("Unable to generate bindings")
-        .write_to_file(out_path.join("bindings.rs"))
-        .expect("Couldn't write bindings!");
+        .map_err(|_| anyhow::anyhow!("Unable to generate bindings"))?
+        .write_to_file(out_path.join("bindings.rs"))?;
+
+    Ok(())
 }
 
 fn build_stubs(cc_builder: &mut cc::Build) {
@@ -218,18 +235,38 @@ fn build_stubs(cc_builder: &mut cc::Build) {
         .expect("Couldn't write bindings!");
 }
 
-fn run_build(use_stub_api: bool) {
-    let mut cc_builder = cc::Build::new();
-    cc_builder
+fn create_builder() -> cc::Build {
+    let mut builder = cc::Build::new();
+    builder
         .cpp(true)
         .compiler("g++")
         .flag("-std=c++17")
         .flag("-fPIC")
         .flag("-Wno-unused-parameter")
         .flag("-Wno-unused-variable");
+    builder
+}
+
+fn run_build(use_stub_api: bool) {
+    let mut cc_builder = create_builder();
 
     if !use_stub_api {
-        build_nixl(&mut cc_builder);
+        let no_fallback = env::var("NIXL_NO_STUBS_FALLBACK")
+            .map(|v| v == "1")
+            .unwrap_or(false);
+
+        if let Err(e) = build_nixl(&mut cc_builder) {
+            if !no_fallback {
+                println!(
+                    "cargo:warning=NIXL build failed: {}, falling back to stub API",
+                    e
+                );
+                let mut stub_builder = create_builder();
+                build_stubs(&mut stub_builder);
+            } else {
+                panic!("Failed to build NIXL: {}", e);
+            }
+        }
     } else {
         build_stubs(&mut cc_builder);
     }

src/bindings/rust/src/lib.rs

@@ -67,7 +67,7 @@ use bindings::{
     nixl_capi_query_resp_list_get_params, nixl_capi_prep_xfer_dlist, nixl_capi_release_xfer_dlist_handle,
     nixl_capi_make_xfer_req, nixl_capi_get_local_partial_md,
     nixl_capi_send_local_partial_md, nixl_capi_query_xfer_backend, nixl_capi_opt_args_set_ip_addr,
-    nixl_capi_opt_args_set_port, nixl_capi_get_xfer_telemetry
+    nixl_capi_opt_args_set_port, nixl_capi_get_xfer_telemetry, nixl_capi_is_stub
 };
 
 // Re-export status codes
@@ -559,3 +559,7 @@ impl NixlRegistration for SystemStorage {
         Ok(())
     }
 }
+
+pub fn is_stub() -> bool {
+    unsafe { nixl_capi_is_stub() }
+}

src/bindings/rust/stubs.cpp

@@ -94,6 +94,20 @@ nixl_capi_load_remote_md(nixl_capi_agent_t agent, const void* data, size_t len,
   return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_send_local_md(nixl_capi_agent_t agent, nixl_capi_opt_args_t opt_args)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_send_local_partial_md(nixl_capi_agent_t agent,
+                                nixl_capi_reg_dlist_t descs,
+                                nixl_capi_opt_args_t opt_args)
+{
+  return nixl_capi_stub_abort();
+}
+
 nixl_capi_status_t
 nixl_capi_prep_xfer_dlist(nixl_capi_agent_t agent,
                           const char *agent_name,
@@ -129,6 +143,30 @@ nixl_capi_invalidate_remote_md(nixl_capi_agent_t agent, const char* remote_agent
   return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_invalidate_local_md(nixl_capi_agent_t agent, nixl_capi_opt_args_t opt_args)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_check_remote_md(nixl_capi_agent_t agent, const char* remote_name, nixl_capi_xfer_dlist_t descs)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_fetch_remote_md(nixl_capi_agent_t agent, const char* remote_name, nixl_capi_opt_args_t opt_args)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_agent_make_connection(nixl_capi_agent_t agent, const char* remote_agent, nixl_capi_opt_args_t opt_args)
+{
+  return nixl_capi_stub_abort();
+}
+
 nixl_capi_status_t
 nixl_capi_get_available_plugins(nixl_capi_agent_t agent, nixl_capi_string_list_t* plugins)
 {
@@ -340,6 +378,42 @@ nixl_capi_xfer_dlist_resize(nixl_capi_xfer_dlist_t dlist, size_t new_size)
   return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_xfer_dlist_get_type(nixl_capi_xfer_dlist_t dlist, nixl_capi_mem_type_t* mem_type)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_xfer_dlist_desc_count(nixl_capi_xfer_dlist_t dlist, size_t* count)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_xfer_dlist_is_empty(nixl_capi_xfer_dlist_t dlist, bool* is_empty)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_xfer_dlist_trim(nixl_capi_xfer_dlist_t dlist)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_xfer_dlist_rem_desc(nixl_capi_xfer_dlist_t dlist, int index)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_xfer_dlist_print(nixl_capi_xfer_dlist_t dlist)
+{
+  return nixl_capi_stub_abort();
+}
+
 // Registration descriptor list functions
 nixl_capi_status_t
 nixl_capi_create_reg_dlist(nixl_capi_mem_type_t mem_type, nixl_capi_reg_dlist_t *dlist) {
@@ -374,6 +448,42 @@ nixl_capi_reg_dlist_resize(nixl_capi_reg_dlist_t dlist, size_t new_size)
   return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_reg_dlist_get_type(nixl_capi_reg_dlist_t dlist, nixl_capi_mem_type_t* mem_type)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_reg_dlist_desc_count(nixl_capi_reg_dlist_t dlist, size_t* count)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_reg_dlist_is_empty(nixl_capi_reg_dlist_t dlist, bool* is_empty)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_reg_dlist_trim(nixl_capi_reg_dlist_t dlist)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_reg_dlist_rem_desc(nixl_capi_reg_dlist_t dlist, int index)
+{
+  return nixl_capi_stub_abort();
+}
+
+nixl_capi_status_t
+nixl_capi_reg_dlist_print(nixl_capi_reg_dlist_t dlist)
+{
+  return nixl_capi_stub_abort();
+}
+
 // Memory registration functions
 nixl_capi_status_t
 nixl_capi_register_mem(nixl_capi_agent_t agent, nixl_capi_reg_dlist_t dlist, nixl_capi_opt_args_t opt_args)
@@ -416,6 +526,17 @@ nixl_capi_query_xfer_backend(nixl_capi_agent_t agent,
     return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_estimate_xfer_cost(nixl_capi_agent_t agent,
+                             nixl_capi_xfer_req_t req_hndl,
+                             nixl_capi_opt_args_t opt_args,
+                             int64_t *duration_us,
+                             int64_t *err_margin_us,
+                             nixl_capi_cost_t *method)
+{
+  return nixl_capi_stub_abort();
+}
+
 nixl_capi_status_t
 nixl_capi_destroy_xfer_req(nixl_capi_xfer_req_t req)
 {
@@ -434,6 +555,13 @@ nixl_capi_get_notifs(nixl_capi_agent_t agent, nixl_capi_notif_map_t notif_map, n
   return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_gen_notif(nixl_capi_agent_t agent, const char* remote_agent,
+                    const void* data, size_t len, nixl_capi_opt_args_t opt_args)
+{
+  return nixl_capi_stub_abort();
+}
+
 nixl_capi_status_t
 nixl_capi_create_notif_map(nixl_capi_notif_map_t* notif_map)
 {
@@ -514,4 +642,17 @@ nixl_capi_query_mem(nixl_capi_agent_t agent,
     return nixl_capi_stub_abort();
 }
 
+nixl_capi_status_t
+nixl_capi_get_xfer_telemetry(nixl_capi_agent_t agent,
+                             nixl_capi_xfer_req_t req_hndl,
+                             nixl_capi_xfer_telemetry_t telemetry)
+{
+  return nixl_capi_stub_abort();
+}
+
+bool nixl_capi_is_stub()
+{
+  return true;
+}
+
 }  // extern "C"

src/bindings/rust/wrapper.cpp

@@ -1903,4 +1903,7 @@ nixl_capi_get_xfer_telemetry(nixl_capi_agent_t agent,
         return NIXL_CAPI_ERROR_BACKEND;
     }
 }
+bool nixl_capi_is_stub() {
+    return false;
+}
 } // extern "C"

src/bindings/rust/wrapper.h

@@ -354,6 +354,7 @@ nixl_capi_get_xfer_telemetry(nixl_capi_agent_t agent,
                              nixl_capi_xfer_req_t req_hndl,
                              nixl_capi_xfer_telemetry_t telemetry);
 
+bool nixl_capi_is_stub();
 
 #ifdef __cplusplus
 }