Add fwu update agent deployment for linux-pc/posix

The fwu update agent can be deployed in different
execution environments to suite platform requirements.
This commit adds a deployment where the fwu update
agent runs within a command-line app for Posix
environments where the firmware image file is accessible
via standard file io. Can be built to run in a native PC
environment to enable a disk image file to be inspected.

Signed-off-by: Julian Hall <julian.hall@arm.com>
Change-Id: I3a652c7ab201c5b7059f8dd1bb6b590e6d8c4c37
diff --git a/deployments/fwu/env/posix/fwu_main.cpp b/deployments/fwu/env/posix/fwu_main.cpp
new file mode 100644
index 0000000..e01640a
--- /dev/null
+++ b/deployments/fwu/env/posix/fwu_main.cpp
@@ -0,0 +1,252 @@
+/*
+ * Copyright (c) 2023, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <string>
+#include <sstream>
+#include <sys/stat.h>
+#include <common/uuid/uuid.h>
+#include <service/fwu/app/fwu_app.h>
+#include "cmd_update_image.h"
+#include "cmd_print_image_dir.h"
+#include "cmd_print_metadata_v1.h"
+#include "cmd_print_metadata_v2.h"
+
+static bool option_selected(
+	const char *option_switch,
+	int argc, char *argv[]);
+
+static std::string parse_string_option(
+	const char *option_switch,
+	int argc, char *argv[],
+	const char *default_val);
+
+static int parse_numeric_option(
+	const char *option_switch,
+	int argc, char *argv[],
+	int default_val);
+
+static bool file_exists(
+	const std::string &filename);
+
+static void print_usage(void);
+static void print_help(void);
+
+
+int main(int argc, char *argv[])
+{
+	fwu_app app;
+	std::string disk_img_filename;
+	std::string update_img_filename;
+	std::string img_type_uuid;
+
+	/* Check for help */
+	if (option_selected("-h", argc, argv) ||
+		option_selected("-help", argc, argv) ||
+		option_selected("--help", argc, argv)) {
+
+		print_help();
+		return 0;
+	}
+
+	/* Handle mandatory disk image filename. Must be first argument */
+	if (argc > 1)
+		disk_img_filename = std::string(argv[1]);
+	else {
+
+		printf("Error: missing disk-filename argument\n");
+		print_usage();
+		return -1;
+	}
+
+	/* Check if disk image file exists */
+	if (!file_exists(disk_img_filename)) {
+
+		printf("Error: %s does not exist\n", disk_img_filename.c_str());
+		return -1;
+	}
+
+	/* Create fwu configuration based on the input disk image */
+	int status = app.configure(disk_img_filename.c_str());
+
+	if (status) {
+
+		printf("Error: failed to configure with status: %d\n", status);
+		return -1;
+	}
+
+	/* Attempt to derive boot info from metadata. Assume bootloader booted from the
+	 * active index. This can be overridden via command-line parameter.
+	 */
+	unsigned int boot_index;
+	unsigned int metadata_version;
+
+	status = app.get_boot_info(boot_index, metadata_version);
+
+	if (status) {
+
+		printf("No recognised metadata, assume default boot index and version\n");
+
+		boot_index = 0;
+		metadata_version = 2;
+	}
+
+	/* Allow for command-line overrides */
+	boot_index = parse_numeric_option("-boot-index", argc, argv, boot_index);
+	metadata_version = parse_numeric_option("-meta-ver", argc, argv, metadata_version);
+
+	/* Options for printing fwu info */
+	bool is_print_img_dir = option_selected("-dir", argc, argv);
+	bool is_print_metadata = option_selected("-meta", argc, argv);
+
+	/* Parse input image related parameters*/
+	update_img_filename = parse_string_option("-img", argc, argv, "");
+	img_type_uuid = parse_string_option("-img-type", argc, argv, "");
+
+	/* Check if image file exists (if one was specified) */
+	if (!update_img_filename.empty() && !file_exists(update_img_filename)) {
+
+		printf("Error: %s does not exist\n", update_img_filename.c_str());
+		return -1;
+	}
+
+	/* Check if img type canonical uuid is well formed */
+	if (!img_type_uuid.empty() && !uuid_is_valid(img_type_uuid.c_str())) {
+
+		printf("Error: image type uuid invalid\n");
+		return -1;
+	}
+
+	/* Initialise the update_agent. Missing or corrupt metadata will get repaired
+	 */
+	status = app.init_update_agent(boot_index, metadata_version);
+
+	if (!status) {
+
+		printf("Update agent started: boot index: %d metadata ver: %d\n",
+			boot_index, metadata_version);
+
+		if (is_print_img_dir)
+			cmd_print_image_dir(app);
+
+		if (is_print_metadata) {
+
+			if (metadata_version == 1)
+				cmd_print_metadata_v1(app);
+			else if (metadata_version == 2)
+				cmd_print_metadata_v2(app);
+			else
+				printf("Unsupported metadata version\n");
+
+		}
+
+		if (!update_img_filename.empty() && !img_type_uuid.empty()) {
+
+			status = cmd_update_image(app, img_type_uuid, update_img_filename);
+
+		} else if (!update_img_filename.empty() || !img_type_uuid.empty()) {
+
+			printf("Error: both image filename and uuid arguments are needed\n");
+			return -1;
+		}
+	}
+
+	if (!status)
+		printf("OK\n");
+	else
+		printf("Error status: %d\n", status);
+
+	return status;
+}
+
+static bool option_selected(
+	const char *option_switch,
+	int argc, char *argv[])
+{
+	bool is_selected = false;
+
+	for (int i = 1; (i < argc) && !is_selected; ++i) {
+
+		is_selected = (strcmp(argv[i], option_switch) == 0);
+	}
+
+	return is_selected;
+}
+
+static std::string parse_string_option(
+	const char *option_switch,
+	int argc, char *argv[],
+	const char *default_val)
+{
+	std::string option = std::string(default_val);
+
+	for (int i = 1; i + 1 < argc; ++i) {
+
+		if (strcmp(argv[i], option_switch) == 0) {
+
+			option = std::string(argv[i + 1]);
+			break;
+		}
+	}
+
+	return option;
+}
+
+static int parse_numeric_option(
+	const char *option_switch,
+	int argc, char *argv[],
+	int default_val)
+{
+	int option = default_val;
+
+	for (int i = 1; i + 1 < argc; ++i) {
+
+		if (strcmp(argv[i], option_switch) == 0) {
+
+			std::istringstream iss(argv[i + 1]);
+			int val;
+
+			iss >> val;
+
+			if (!iss.fail())
+				option = val;
+
+			break;
+		}
+	}
+
+	return option;
+}
+
+static bool file_exists(const std::string &filename)
+{
+	struct stat stat_buf;
+
+	return stat(filename.c_str(), &stat_buf) == 0;
+}
+
+static void print_usage(void)
+{
+	printf("Usage: fwu disk-filename [-dir -meta] [-boot-index number -meta-ver number] "
+		   "[-img filename -img-type uuid]\n");
+}
+
+static void print_help(void)
+{
+	print_usage();
+
+	printf("\n");
+	printf("\tdisk-filename\tDisk image file to update\n");
+	printf("\t-dir\t\tPrint image directory\n");
+	printf("\t-meta\t\tPrint FWU metadata\n");
+	printf("\t-boot-index\tOverride default boot index [0..n]\n");
+	printf("\t-meta-ver\tSpecify FWU metadata to use\n");
+	printf("\t-img\t\tFile containing image update\n");
+	printf("\t-img-type\tCanonical UUID of image to update\n");
+}
+