tests: posix: add POSIX_SYSTEM_DATABASE_R testsuite

Add a teststuite to exercise the POSIX_SYSTEM_DATABASE_R
Option Group.

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>

Author: cfriedt

tests/posix/common/src/grp.c

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <ff.h>
 #include "test_fs.h"
 
 ZTEST_SUITE(posix_fs_test, NULL, test_mount, NULL, NULL, test_unmount);

tests/posix/common/src/pwd.c

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(posix_system_database_r)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})
+
+target_compile_options(app PRIVATE -U_POSIX_C_SOURCE -D_POSIX_C_SOURCE=200809L)

tests/posix/fs/src/main.c

@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2023 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	ramdisk0 {
+		compatible = "zephyr,ram-disk";
+		disk-name = "RAM";
+		sector-size = <512>;
+		sector-count = <160>;
+	};
+};

tests/posix/system_database_r/CMakeLists.txt

@@ -0,0 +1,8 @@
+CONFIG_POSIX_API=y
+CONFIG_ZTEST=y
+
+CONFIG_POSIX_AEP_CHOICE_BASE=y
+CONFIG_POSIX_SYSTEM_DATABASE_R=y
+CONFIG_FAT_FILESYSTEM_ELM=y
+
+CONFIG_MAIN_STACK_SIZE=4096

tests/posix/system_database_r/app.overlay

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2024 Tenstorrent AI ULC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <string.h>
+
+#include <ff.h>
+#include <zephyr/fs/fs.h>
+#include <zephyr/sys/util.h>
+#include <zephyr/ztest.h>
+
+static FATFS _fs;
+
+static struct fs_mount_t _mnt = {
+	.type = FS_FATFS,
+	.mnt_point = "/",
+	.fs_data = &_fs,
+};
+
+struct _entry {
+	const char *const name;
+	const char *const data;
+};
+
+static const struct _entry _data[] = {
+	{.name = "/etc/passwd",
+	 .data = "user:x:1000:1000:user:/home/user:/bin/sh\nroot:x:0:0:root:/root:/bin/sh\n"},
+	{.name = "/etc/group", .data = "user:x:1000:staff,admin\nroot:x:0:\n"},
+};
+
+void *setup(void)
+{
+	int ret;
+
+	memset(&_fs, 0, sizeof(_fs));
+
+	ret = fs_mount(&_mnt);
+	zassert_ok(ret, "mount failed: %d", ret);
+
+	ret = fs_mkdir("/etc");
+	zassert_ok(ret, "mkdir failed: %d", ret);
+
+	ARRAY_FOR_EACH_PTR(_data, entry) {
+		int len;
+		struct fs_file_t zfp;
+
+		fs_file_t_init(&zfp);
+
+		ret = fs_open(&zfp, entry->name, FS_O_CREATE | FS_O_RDWR | FS_O_TRUNC);
+		zassert_true(ret >= 0, "open failed: %d", ret);
+
+		len = strlen(entry->data);
+		ret = fs_write(&zfp, entry->data, len);
+		zassert_equal(ret, len, "%s returned %d instead of %d", "write", ret, len);
+
+		ret = fs_close(&zfp);
+		zassert_ok(ret, "%s returned %d instead of %d", "close", ret, len);
+	};
+
+	return &_mnt;
+}
+
+void teardown(void *arg)
+{
+	struct fs_mount_t *const mnt = arg;
+
+	(void)fs_unmount(mnt);
+}