fixup! test: rewrite sysprof test using managed execution

test/tarantool-c-tests/gh-8594-sysprof-ffunc-crash.test.c

@@ -53,57 +53,46 @@
 extern void *lj_ff_tostring(void);
 extern void *lj_fff_res1(void);
 
-/* Sysprof "/dev/null" stream helpers. {{{ */
+/* Sysprof dummy stream helpers. {{{ */
 
 /*
  * Yep, 8Mb. Tuned in order not to bother the platform with too
  * often flushes.
  */
 #define STREAM_BUFFER_SIZE (8 * 1024 * 1024)
-#define DEVNULL -1
 
-struct devnull_ctx {
-	/*
-	 * XXX: Dummy file descriptor to be used as "/dev/null"
-	 * context indicator in writer and on_stop callback.
-	 */
-	int fd;
+struct dummy_ctx {
 	/* Buffer for data recorded by sysprof. */
 	uint8_t buf[STREAM_BUFFER_SIZE];
 };
 
+static struct dummy_ctx context;
+
 static int stream_new(struct luam_Sysprof_Options *options)
 {
-	struct devnull_ctx *ctx = calloc(1, sizeof(struct devnull_ctx));
-	if (ctx == NULL)
-		return PROFILE_ERRIO;
-
-	/* Set "/dev/null" context indicator. */
-	ctx->fd = DEVNULL;
-	options->ctx = ctx;
-	options->buf = ctx->buf;
+	/* Set dummy context. */
+	options->ctx = &context;
+	options->buf = (uint8_t *)&context.buf;
 	options->len = STREAM_BUFFER_SIZE;
 
 	return PROFILE_SUCCESS;
 }
 
 static int stream_delete(void *rawctx, uint8_t *buf)
 {
-	struct devnull_ctx *ctx = rawctx;
-	assert(ctx->fd == DEVNULL);
-	free(ctx);
+	assert(rawctx == &context);
+	/* XXX: No need to release context memory. Just return. */
 	return PROFILE_SUCCESS;
 }
 
 static size_t stream_writer(const void **buf_addr, size_t len, void *rawctx)
 {
-	struct devnull_ctx *ctx = rawctx;
-	assert(ctx->fd == DEVNULL);
+	assert(rawctx == &context);
 	/* Do nothing, just return back to the profiler. */
 	return STREAM_BUFFER_SIZE;
 }
 
-/* }}} Sysprof "/dev/null" stream helpers. */
+/* }}} Sysprof dummy stream helpers. */
 
 static int tracee(const char *luacode)
 {