Add mnimalistic command line interface "command.c"

This is a very simplistic command line interface parser which
various parts of the code can use to register textual commands
on the debug UART.

Change-Id: I2d289228fb97ecde5602e9756f3d7c51fa65a3b7

4 files changed, 135 insertions, 5 deletions

diff --git a/sysmoOCTSIM/command.c b/sysmoOCTSIM/command.c
new file mode 100644
index 0000000..9502f05
--- /dev/null
+++ b/sysmoOCTSIM/command.c
@@ -0,0 +1,101 @@
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <utils.h>
+
+#include "atmel_start.h"
+#include "command.h"
+
+struct cmd_state {
+	const char *prompt;
+	char buf[128];
+	unsigned int buf_idx;
+	const struct command_fn *cmd[32];
+	unsigned int cmd_idx;
+};
+
+static struct cmd_state g_cmds;
+
+int command_register(const struct command_fn *cmd)
+{
+	if (g_cmds.cmd_idx >= ARRAY_SIZE(g_cmds.cmd))
+		return -1;
+	g_cmds.cmd[g_cmds.cmd_idx++] = cmd;
+	return 0;
+}
+
+DEFUN(help, help_cmd, "help", "Print command reference")
+{
+	unsigned int i;
+	printf("Help:\r\n");
+	printf(" Command          Help\r\n");
+	printf(" ---------------- ----\r\n");
+	for (i = 0; i < g_cmds.cmd_idx; i++)
+		printf(" %-16s %s\r\n", g_cmds.cmd[i]->command, g_cmds.cmd[i]->help);
+}
+
+static void cmd_execute()
+{
+	char *argv[16];
+	unsigned int i;
+	int argc = 0;
+	char *cur;
+
+	printf("\r\n");
+	memset(argv, 0, sizeof(argv));
+
+	for (cur = strtok(g_cmds.buf, " "); cur; cur = strtok(NULL, " ")) {
+		if (argc >= ARRAY_SIZE(argv))
+			break;
+		argv[argc++] = cur;
+	}
+
+	for (i = 0; i < g_cmds.cmd_idx; i++) {
+		if (!strcmp(g_cmds.cmd[i]->command, argv[0])) {
+			g_cmds.cmd[i]->fn(argc, argv);
+			return;
+		}
+	}
+	printf("Unknown command: '%s'\r\n", argv[0]);
+}
+
+static void cmd_buf_reset(void)
+{
+	memset(g_cmds.buf, 0, sizeof(g_cmds.buf));
+	g_cmds.buf_idx = 0;
+}
+
+static void cmd_buf_append(char c)
+{
+	g_cmds.buf[g_cmds.buf_idx++] = c;
+}
+
+void command_try_recv(void)
+{
+	unsigned int i = 0;
+
+	/* yield CPU after maximum of 10 received characters */
+	while (usart_sync_is_rx_not_empty(&UART_debug) && (i < 10)) {
+		int c = getchar();
+		if (c < 0)
+			return;
+		putchar(c);
+		if (c == '\r' || c == '\n' || g_cmds.buf_idx >= sizeof(g_cmds.buf)-1) {
+			cmd_execute();
+			cmd_buf_reset();
+			printf(g_cmds.prompt);
+			return;
+		}
+		/* append character */
+		cmd_buf_append(c);
+
+		i++;
+	}
+}
+
+void command_init(const char *prompt)
+{
+	g_cmds.prompt = prompt;
+	command_register(&help_cmd);
+}
diff --git a/sysmoOCTSIM/command.h b/sysmoOCTSIM/command.h
new file mode 100644
index 0000000..cdf256d
--- /dev/null
+++ b/sysmoOCTSIM/command.h
@@ -0,0 +1,20 @@
+#pragma once
+
+struct command_fn {
+	const char *command;
+	const char *help;
+	void (*fn)(int argc, char **argv);
+};
+
+#define DEFUN(funcname, cmdname, cmdstr, helpstr)	\
+	static void funcname(int argc, char **argv);		\
+	static struct command_fn cmdname = { 			\
+		.command = cmdstr,				\
+		.help = helpstr,				\
+		.fn = funcname,					\
+	};							\
+	static void funcname(int argc, char **argv)
+
+void command_init(const char *prompt);
+int command_register(const struct command_fn *cmd);
+void command_try_recv(void);
diff --git a/sysmoOCTSIM/gcc/Makefile b/sysmoOCTSIM/gcc/Makefile
index 1c90257..7496377 100644
--- a/sysmoOCTSIM/gcc/Makefile
+++ b/sysmoOCTSIM/gcc/Makefile
@@ -80,6 +80,7 @@ main.o \
 i2c_bitbang.o \
 octsim_i2c.o \
 ncn8025.o \
+command.o \
 hpl/osc32kctrl/hpl_osc32kctrl.o \
 examples/driver_examples.o \
 driver_init.o \
@@ -126,6 +127,7 @@ OBJS_AS_ARGS +=  \
 "i2c_bitbang.o" \
 "octsim_i2c.o" \
 "ncn8025.o" \
+"command.o" \
 "hpl/osc32kctrl/hpl_osc32kctrl.o" \
 "examples/driver_examples.o" \
 "driver_init.o" \
@@ -178,6 +180,7 @@ DEPS_AS_ARGS +=  \
 "i2c_bitbang.d" \
 "octsim_i2c.d" \
 "ncn8025.d" \
+"command.d" \
 "examples/driver_examples.d" \
 "hal/src/hal_cache.d" \
 "hal/src/hal_sleep.d" \
diff --git a/sysmoOCTSIM/main.c b/sysmoOCTSIM/main.c
index c79d5aa..ef87162 100644
--- a/sysmoOCTSIM/main.c
+++ b/sysmoOCTSIM/main.c
@@ -27,6 +27,8 @@
 #include "octsim_i2c.h"
 #include "ncn8025.h"
 
+#include "command.h"
+
 
 static void board_init()
 {
@@ -47,6 +49,12 @@ static void board_init()
 	hri_port_set_PINCFG_DRVSTR_bit(PORT, 0, 11);
 }
 
+DEFUN(hello_fn, cmd_hello,
+	"hello", "Hello World example command")
+{
+	printf("Hello World!\r\n");
+}
+
 int main(void)
 {
 	atmel_start_init();
@@ -56,13 +64,11 @@ int main(void)
 	usb_start();
 
 	board_init();
+	command_init("sysmoOCTSIM> ");
+	command_register(&cmd_hello);
 
 	printf("\r\n\r\nsysmocom sysmoOCTSIM\r\n");
 	while (true) { // main loop
-		if (usart_sync_is_rx_not_empty(&UART_debug)) {
-			gpio_toggle_pin_level(USER_LED);
-			int c = getchar();
-			putchar(c);
-		}
+		command_try_recv();
 	}
 }