tests: add unit test for hexagonrpc function

The hexagonrpc function is getting very complex and deserves its own
unit test. Add a unit test for the hexagonrpc function.

Signed-off-by: Richard Acayan <[email protected]>

Author: flamingradian

tests/meson.build

@@ -24,5 +24,13 @@ test_hexagonfs = executable('test_hexagonfs',
   include_directories : include,
 )
 
+test_hexagonrpc = executable('test_hexagonrpc',
+  'test_hexagonrpc.c',
+  '../libhexagonrpc/hexagonrpc.c',
+  c_args : cflags,
+  include_directories : include,
+)
+
 test('iobuffer', test_iobuffer)
 test('hexagonfs', test_hexagonfs, args : [sample_file])
+test('hexagonrpc', test_hexagonrpc)

tests/test_hexagonrpc.c

@@ -0,0 +1,172 @@
+/*
+ * FastRPC reverse tunnel - tests for virtual filesystem
+ *
+ * Copyright (C) 2025 HexagonRPC Contributors
+ *
+ * This file is part of HexagonRPC.
+ *
+ * HexagonRPC is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#define _DEFAULT_SOURCE
+
+#include <libhexagonrpc/hexagonrpc.h>
+#include <misc/fastrpc.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+struct expected_invoke_arg {
+	size_t len;
+	const void *ptr;
+};
+
+static const struct expected_invoke_arg *expected = NULL;
+static uint32_t expected_sc = 0;
+
+static const uint32_t no_args_sc = REMOTE_SCALARS_MAKE(0, 0, 0);
+
+static const struct hrpc_method_def_interp4 no_args_def = {
+	.msg_id = 0,
+	.n_args = 0,
+	.args = NULL,
+	.n_inner_types = 0,
+	.inner_types = NULL,
+};
+
+static const char scalar_arg_exp0[] = {
+	0x67, 0x45, 0x23, 0x01,
+	0x02, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00,
+};
+
+static const char scalar_arg_exp1[] = {
+	'h', 'i',
+};
+
+static const struct expected_invoke_arg scalar_arg_exp[] = {
+	{
+		.len = sizeof(scalar_arg_exp0),
+		.ptr = scalar_arg_exp0,
+	},
+	{
+		.len = sizeof(scalar_arg_exp1),
+		.ptr = scalar_arg_exp1,
+	},
+	{
+		.len = 0,
+		.ptr = NULL,
+	},
+};
+
+static const uint32_t scalar_arg_sc = REMOTE_SCALARS_MAKE(0, 3, 0);
+
+static const struct hrpc_arg_def_interp4 scalar_arg_args[] = {
+	{ HRPC_ARG_WORD, sizeof(uint32_t) },
+	{ HRPC_ARG_BLOB_SEQ, sizeof(char) },
+	{ HRPC_ARG_BLOB_SEQ, sizeof(char) },
+};
+
+static const struct hrpc_method_def_interp4 scalar_arg_def = {
+	.msg_id = 0,
+	.n_args = HRPC_ARRAY_SIZE(scalar_arg_args),
+	.args = scalar_arg_args,
+	.n_inner_types = 0,
+	.inner_types = NULL,
+};
+
+int ioctl(int fd, unsigned long int op, ...)
+{
+	struct fastrpc_invoke *invoke;
+	struct fastrpc_invoke_args *args;
+	size_t i, n_inbufs, n_outbufs;
+	void *data;
+	va_list list;
+
+	va_start(list, op);
+	data = va_arg(list, void *);
+	va_end(list);
+
+	if (op != FASTRPC_IOCTL_INVOKE) {
+		return syscall(SYS_ioctl, fd, op, data);
+	} else {
+		invoke = data;
+
+		if (fd != -1)
+			return -1;
+
+		if (invoke->handle != 0)
+			return -1;
+
+		if (invoke->sc != expected_sc)
+			return -1;
+
+		n_inbufs = REMOTE_SCALARS_INBUFS(invoke->sc);
+		n_outbufs = REMOTE_SCALARS_OUTBUFS(invoke->sc);
+		args = (struct fastrpc_invoke_args *) invoke->args;
+
+		for (i = 0; i < n_inbufs; i++) {
+			if (args[i].fd != -1 || args[i].attr != 0)
+				return -1;
+
+			if (args[i].length != expected[i].len)
+				return -1;
+
+			if (memcmp((void *) args[i].ptr,
+				   expected[i].ptr,
+				   args[i].length))
+				return -1;
+		}
+
+		for (i = n_inbufs; i < n_inbufs + n_outbufs; i++) {
+			if (args[i].fd != -1 || args[i].attr != 0)
+				return -1;
+
+			if (args[i].length < expected[i].len)
+				return -1;
+
+			memcpy((void *) args[i].ptr,
+			       expected[i].ptr,
+			       args[i].length);
+		}
+
+		return 0;
+	}
+}
+
+int main(void)
+{
+	int ret, fd = -1;
+	uint32_t hdl = 0;
+
+	expected_sc = no_args_sc;
+	expected = NULL;
+	ret = hexagonrpc(&no_args_def, fd, hdl);
+	if (ret)
+		return 1;
+
+	expected_sc = scalar_arg_sc;
+	expected = scalar_arg_exp;
+	ret = hexagonrpc(&scalar_arg_def, fd, hdl,
+			 (uint32_t) 0x01234567,
+			 (uint32_t) 2, (const void *) "hi");
+	if (ret)
+		return 1;
+
+	return 0;
+}