alias: Add option to use relative alias offset

DONE: RTOS-713

cmds/alias.c

@@ -5,8 +5,8 @@
  *
  * Create file alias
  *
- * Copyright 2021 Phoenix Systems
- * Author: Hubert Buczynski
+ * Copyright 2021, 2023 Phoenix Systems
+ * Author: Hubert Buczynski, Aleksander Kaminski
  *
  * This file is part of Phoenix-RTOS.
  *
@@ -17,11 +17,16 @@
 
 #include <hal/hal.h>
 #include <phfs/phfs.h>
+#include <lib/getopt.h>
+#include <lib/log.h>
+
+
+static addr_t aliasBase = 0;
 
 
 static void cmd_aliasInfo(void)
 {
-	lib_printf("sets alias to file, usage: alias [<name> <offset> <size>]");
+	lib_printf("sets alias to file, usage: alias [-b <base> | [-r] <name> <offset> <size>]");
 }
 
 
@@ -30,38 +35,85 @@ static int cmd_alias(int argc, char *argv[])
 	char *end;
 	size_t sz = 0;
 	addr_t addr = 0;
-	unsigned int i;
+	int c, relative = 0;
+	addr_t newBase;
 
 	if (argc == 1) {
+		lib_printf("\nRelative alias base: 0x%p", aliasBase);
 		phfs_aliasesShow();
-		return EOK;
+		return CMD_EXIT_SUCCESS;
 	}
-	else if (argc != 4) {
-		log_error("\n%s: Wrong argument count", argv[0]);
-		return -EINVAL;
+
+	for (;;) {
+		c = lib_getopt(argc, argv, "rb:");
+		if (c < 0) {
+			break;
+		}
+
+		switch (c) {
+			case 'r':
+				relative = 1;
+				break;
+
+			case 'b':
+				if (argc != 3) {
+					log_error("\n%s: Invalid argument count.\n", argv[0]);
+					cmd_aliasInfo();
+					return CMD_EXIT_FAILURE;
+				}
+
+				newBase = lib_strtoul(optarg, &end, 0);
+				if (*end != '\0') {
+					log_error("\n%s: Invalid base.\n", argv[0]);
+					cmd_aliasInfo();
+					return CMD_EXIT_FAILURE;
+				}
+
+				aliasBase = newBase;
+
+				/* Ignore everything else, this is a separate function */
+				return CMD_EXIT_SUCCESS;
+
+			default:
+				log_error("\n%s: Invalid option: %c\n", argv[0], c);
+				cmd_aliasInfo();
+				return CMD_EXIT_FAILURE;
+		}
 	}
 
+	if ((argc - optind) != 3) {
+		log_error("\n%s: Wrong argument count %d", argv[0]);
+		return CMD_EXIT_FAILURE;
+	}
 
-	for (i = 2; i < 4; ++i) {
-		if (i == 2)
-			addr = lib_strtoul(argv[i], &end, 0);
-		else if (i == 3)
-			sz = lib_strtoul(argv[i], &end, 0);
+	addr = lib_strtoul(argv[optind + 1], &end, 0);
+	if (*end != '\0') {
+		log_error("\n%s: Wrong arguments", argv[0]);
+		return CMD_EXIT_FAILURE;
+	}
+
+	sz = lib_strtoul(argv[optind + 2], &end, 0);
+	if (*end != '\0') {
+		log_error("\n%s: Wrong arguments", argv[0]);
+		return CMD_EXIT_FAILURE;
+	}
 
-		if (*end) {
-			log_error("\n%s: Wrong arguments", argv[0]);
-			return -EINVAL;
+	if (relative != 0) {
+		if (addr + aliasBase < addr) {
+			log_error("\n%s: Relative offset overflow", argv[0]);
+			return CMD_EXIT_FAILURE;
 		}
+		addr += aliasBase;
 	}
 
-	if (phfs_aliasReg(argv[1], addr, sz) < 0) {
+	if (phfs_aliasReg(argv[optind], addr, sz) < 0) {
 		log_error("\nCan't register file %s", argv[1]);
-		return -EINVAL;
+		return CMD_EXIT_FAILURE;
 	}
 
 	log_info("\nRegistering file %s ", argv[1]);
 
-	return EOK;
+	return CMD_EXIT_SUCCESS;
 }