compat.wamr: no-hw-bound-check, instruction-metering and thread-mgr features (#506)

Three runtime build options as features, with a test member that stops an
endless guest loop by instruction budget and by wasm_runtime_terminate()
from another thread. thread-mgr also needs its directory in the base
include_dirs, and on openkal-musl a target_cfg define, because openkal has
no sigaction for the wakeup handler.

Author: yspbwx2010

mcpp.toml

@@ -182,6 +182,7 @@ members = [
     "tests/examples/vulkan-memory-allocator",
     "tests/examples/wamr",
     "tests/examples/wamr-features",
+    "tests/examples/wamr-runtime-features",
     "tests/examples/quickjs-ng",
 ]
 

pkgs/c/compat.wamr.lua

@@ -81,6 +81,10 @@
 -- compat.recastnavigation's DT_POLYREF64 out of the feature table does not
 -- apply here.
 --
+-- `no-hw-bound-check`, `instruction-metering` and `thread-mgr` select runtime
+-- build options rather than a guest library. They are defines of the same kind:
+-- neither wasm_export.h nor wasm_c_api.h branches on any of them.
+--
 -- ─────────────────────────────────────────────────────────────────────────
 -- CN MIRROR
 --
@@ -140,6 +144,8 @@ package = {
             "*/core/iwasm/libraries/libc-wasi/sandboxed-system-primitives/include",
             "*/core/iwasm/libraries/libc-wasi/sandboxed-system-primitives/src",
             "*/core/shared/platform/common/libc-util",
+            -- wasm_c_api.c includes thread_manager.h by bare name under thread-mgr
+            "*/core/iwasm/libraries/thread-mgr",
             "mcpp_generated/include",
         },
 
@@ -165,6 +171,14 @@ package = {
             ldflags = { "-lpthread", "-lm" },
         },
 
+        target_cfg = {
+            -- openkal has no sigaction: with thread-mgr, wasm_runtime_init cannot
+            -- install its wakeup handler and returns false
+            ["cfg(all(kernel-abi = \"openkal\", c-abi = \"musl\"))"] = {
+                cflags = { "-DWASM_DISABLE_WAKEUP_BLOCKING_OP=1" },
+            },
+        },
+
         generated_files = {
             ["mcpp_generated/include/mcpp_wamr_config.h"] =
 [==[
@@ -239,6 +253,18 @@ package = {
         targets = { ["wamr"] = { kind = "lib" } },
 
         features = {
+            -- software bound checks only: no guard pages, sigaltstack or SIGSEGV handler
+            ["no-hw-bound-check"] = {
+                defines = { "WASM_DISABLE_HW_BOUND_CHECK=1" },
+            },
+            ["instruction-metering"] = {
+                defines = { "WASM_ENABLE_INSTRUCTION_METERING=1" },
+            },
+            -- wasm_runtime_terminate() from another thread stops a running guest
+            ["thread-mgr"] = {
+                sources = { "*/core/iwasm/libraries/thread-mgr/*.c" },
+                defines = { "WASM_ENABLE_THREAD_MGR=1" },
+            },
             -- Built-in libc wrappers exported to the guest under `env`.
             ["libc-builtin"] = {
                 sources = { "*/core/iwasm/libraries/libc-builtin/*.c" },

tests/examples/wamr-runtime-features/mcpp.toml

@@ -0,0 +1,9 @@
+# WAMR execution-control features: software bound checks, instruction
+# metering and the thread manager. The base member (tests/examples/wamr) does
+# not request them.
+[package]
+name = "wamr-runtime-features-tests"
+version = "0.1.0"
+
+[target.'cfg(linux)'.dependencies.compat]
+wamr = { version = "2.4.5", features = ["no-hw-bound-check", "instruction-metering", "thread-mgr"] }

tests/examples/wamr-runtime-features/tests/runtime_features.cpp

@@ -0,0 +1,116 @@
+// compat.wamr with `no-hw-bound-check`, `instruction-metering` and
+// `thread-mgr`: an infinite loop in the guest is stopped once by the
+// instruction budget and once by wasm_runtime_terminate() from another thread.
+#ifdef __linux__
+
+#include <wasm_export.h>
+
+#include <pthread.h>
+#include <unistd.h>
+
+#include <atomic>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+namespace {
+
+// (module
+//   (func (export "spin") (loop (br 0)))
+//   (func (export "add") (param i32 i32) (result i32)
+//     local.get 0  local.get 1  i32.add))
+const unsigned char kModule[] = {
+    0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00,
+    0x01, 0x0a, 0x02, 0x60, 0x00, 0x00, 0x60, 0x02, 0x7f, 0x7f, 0x01, 0x7f,
+    0x03, 0x03, 0x02, 0x00, 0x01,
+    0x07, 0x0e, 0x02, 0x04, 's', 'p', 'i', 'n', 0x00, 0x00,
+                      0x03, 'a', 'd', 'd', 0x00, 0x01,
+    0x0a, 0x11, 0x02, 0x07, 0x00, 0x03, 0x40, 0x0c, 0x00, 0x0b, 0x0b,
+                      0x07, 0x00, 0x20, 0x00, 0x20, 0x01, 0x6a, 0x0b,
+};
+
+wasm_module_inst_t g_inst;
+wasm_exec_env_t g_env;
+std::atomic<bool> g_returned{ false };
+
+bool call(const char *name, uint32_t *argv, uint32_t argc)
+{
+    return wasm_runtime_call_wasm(g_env, wasm_runtime_lookup_function(g_inst, name), argc, argv);
+}
+
+bool exception_has(const char *text)
+{
+    const char *ex = wasm_runtime_get_exception(g_inst);
+    std::printf("  exception: %s\n", ex ? ex : "(none)");
+    return ex && std::strstr(ex, text);
+}
+
+bool usable_again()
+{
+    wasm_runtime_clear_exception(g_inst);
+    uint32_t argv[2] = { 2, 3 };
+    return call("add", argv, 2) && argv[0] == 5;
+}
+
+// Repeats until the call has returned, so a terminate that lands before the
+// guest started running is not lost.
+void *terminate_until_returned(void *)
+{
+    while (!g_returned) {
+        usleep(100 * 1000);
+        wasm_runtime_terminate(g_inst);
+    }
+    return nullptr;
+}
+
+} // namespace
+
+int main()
+{
+    alarm(60);
+
+    RuntimeInitArgs init;
+    std::memset(&init, 0, sizeof init);
+    init.mem_alloc_type = Alloc_With_System_Allocator;
+    if (!wasm_runtime_full_init(&init)) {
+        std::puts("wasm_runtime_full_init failed");
+        return 1;
+    }
+
+    char err[128] = { 0 };
+    unsigned char *image = static_cast<unsigned char *>(std::malloc(sizeof kModule));
+    std::memcpy(image, kModule, sizeof kModule);
+    wasm_module_t mod = wasm_runtime_load(image, sizeof kModule, err, sizeof err);
+    g_inst = mod ? wasm_runtime_instantiate(mod, 16 * 1024, 0, err, sizeof err) : nullptr;
+    g_env = g_inst ? wasm_runtime_create_exec_env(g_inst, 16 * 1024) : nullptr;
+    if (!g_env) {
+        std::printf("module setup failed: %s\n", err);
+        return 1;
+    }
+
+    uint32_t argv[2] = { 0, 0 };
+    bool ok = true;
+
+    wasm_runtime_set_instruction_count_limit(g_env, 1000000);
+    bool stopped = !call("spin", argv, 0) && exception_has("instruction limit");
+    std::printf("budget stops the loop     %s\n", stopped ? "ok" : "FAIL");
+    ok = ok && stopped && usable_again();
+
+    wasm_runtime_set_instruction_count_limit(g_env, -1);
+    pthread_t th;
+    pthread_create(&th, nullptr, terminate_until_returned, nullptr);
+    bool terminated = !call("spin", argv, 0) && exception_has("terminated by user");
+    g_returned = true;
+    pthread_join(th, nullptr);
+    std::printf("terminate stops the loop  %s\n", terminated ? "ok" : "FAIL");
+    ok = ok && terminated && usable_again();
+
+    std::printf("instance usable afterwards %s\n", ok ? "ok" : "FAIL");
+    return ok ? 0 : 1;
+}
+
+#else
+
+int main() { return 0; }
+
+#endif