[RFC PATCH v4 12/28] cmd: Add new parser command.

[Francis Laniel <francis.laniel@amarulasolutions.com>]

This command can be used to print the current parser with 'parser print'.
It can also be used to set the current parser with 'parser set'.
For the moment, only one value is valid for set: old.

Signed-off-by: Francis Laniel <francis.laniel@amarulasolutions.com>
---
 cmd/Makefile |   2 +
 cmd/parser.c | 113 +++++++++++++++++++++++++++++++++++++++++++++++++++
 common/cli.c |   3 +-
 3 files changed, 117 insertions(+), 1 deletion(-)
 create mode 100644 cmd/parser.c

diff --git a/cmd/Makefile b/cmd/Makefile
index 5e43a1e022..11ae749a92 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -205,6 +205,8 @@ obj-$(CONFIG_CMD_AVB) += avb.o
 # Foundries.IO SCP03
 obj-$(CONFIG_CMD_SCP03) += scp03.o
 
+obj-$(CONFIG_HUSH_PARSER) += parser.o
+
 obj-$(CONFIG_ARM) += arm/
 obj-$(CONFIG_RISCV) += riscv/
 obj-$(CONFIG_SANDBOX) += sandbox/
diff --git a/cmd/parser.c b/cmd/parser.c
new file mode 100644
index 0000000000..4283bc7566
--- /dev/null
+++ b/cmd/parser.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <common.h>
+#include <cli.h>
+#include <command.h>
+#include <string.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const char *gd_flags_to_parser(void)
+{
+	if (gd->flags & GD_FLG_HUSH_OLD_PARSER)
+		return "old";
+	return NULL;
+}
+
+static int do_parser_get(struct cmd_tbl *cmdtp, int flag, int argc,
+			      char *const argv[])
+{
+	const char *current = gd_flags_to_parser();
+
+	if (!current) {
+		printf("current parser value is not valid, this should not happen!\n");
+		return CMD_RET_FAILURE;
+	}
+
+	printf("%s\n", current);
+
+	return CMD_RET_SUCCESS;
+}
+
+static int parser_string_to_gd_flags(const char *parser)
+{
+	if (!strcmp(parser, "old"))
+		return GD_FLG_HUSH_OLD_PARSER;
+	return -1;
+}
+
+static void reset_parser_gd_flags(void)
+{
+	gd->flags &= ~GD_FLG_HUSH_OLD_PARSER;
+}
+
+static int do_parser_set(struct cmd_tbl *cmdtp, int flag, int argc,
+			      char *const argv[])
+{
+	char *parser_name;
+	int parser_flag;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	parser_name = argv[1];
+
+	parser_flag = parser_string_to_gd_flags(parser_name);
+	if (parser_flag == -1) {
+		printf("Bad value for parser name: %s\n", parser_name);
+		return CMD_RET_USAGE;
+	}
+
+	if (parser_flag == GD_FLG_HUSH_OLD_PARSER
+		&& !CONFIG_IS_ENABLED(HUSH_OLD_PARSER)) {
+		printf("Want to set current parser to old, but its code was not compiled!\n");
+		return CMD_RET_FAILURE;
+	}
+	reset_parser_gd_flags();
+	gd->flags |= parser_flag;
+
+	cli_init();
+	cli_loop();
+
+	/* cli_loop() should never return. */
+	return CMD_RET_FAILURE;
+}
+
+static struct cmd_tbl parser_sub[] = {
+	U_BOOT_CMD_MKENT(get, 1, 1, do_parser_get, "", ""),
+	U_BOOT_CMD_MKENT(set, 2, 1, do_parser_set, "", ""),
+};
+
+static int do_parser(struct cmd_tbl *cmdtp, int flag, int argc,
+			char *const argv[])
+{
+	struct cmd_tbl *cp;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	/* drop initial "parser" arg */
+	argc--;
+	argv++;
+
+	cp = find_cmd_tbl(argv[0], parser_sub, ARRAY_SIZE(parser_sub));
+	if (cp)
+		return cp->cmd(cmdtp, flag, argc, argv);
+
+	return CMD_RET_USAGE;
+}
+
+#if CONFIG_IS_ENABLED(SYS_LONGHELP)
+static char parser_help_text[] =
+	"get - print current parser\n"
+	"set - set the current parser, possible value is: old"
+	;
+#endif
+
+U_BOOT_CMD(parser, 3, 1, do_parser,
+	   "parser",
+#if CONFIG_IS_ENABLED(SYS_LONGHELP)
+	   parser_help_text
+#endif
+);
diff --git a/common/cli.c b/common/cli.c
index ef967f4f9e..82c69e5573 100644
--- a/common/cli.c
+++ b/common/cli.c
@@ -239,7 +239,8 @@ void cli_loop(void)
 void cli_init(void)
 {
 #ifdef CONFIG_HUSH_PARSER
-	if (!(gd->flags & GD_FLG_HUSH_OLD_PARSER))
+	if (!(gd->flags & GD_FLG_HUSH_OLD_PARSER)
+		&& CONFIG_IS_ENABLED(HUSH_OLD_PARSER))
 		gd->flags |= GD_FLG_HUSH_OLD_PARSER;
 	u_boot_hush_start();
 #endif
-- 
2.25.1