integrate microvty

libcommon/include/libcommon/microvty.h

@@ -0,0 +1,44 @@
+#pragma once
+#include <stdbool.h>
+
+/* micrVTY - small implementation of a limited feature command line interface
+ * (C) 2019 by Harald Welte <laforge@gnumonks.org>
+ *
+ * modelled after libosmovty (part of libosmocore.git), which in turn is a fork
+ * of the command line interface of GNU zebra / quagga.
+ *
+ * microVTY is intended for very small bare-iron microcontroller. It doesn't need
+ * any dynamic allocations/heap, and tries to stay very simplistic to conserve
+ * resources.
+ */
+
+/*! Total size in bytes for microvty command buffer (max command line length) */
+#define MICROVTY_CMD_BUF_SIZE 128
+
+/*! Maximum number of VTY commands that can be registered with microvty_register() */
+#define MICROVTY_MAX_CMD 32
+
+struct microvty_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 microvty_fn cmdname = { 			\
+		.command = cmdstr,				\
+		.help = helpstr,				\
+		.fn = funcname,					\
+	};							\
+	static void funcname(int argc __attribute__((unused)), \
+			     char **argv __attribute__((unused)))
+
+void microvty_init(const char *prompt);
+int microvty_register(const struct microvty_fn *cmd);
+void microvty_try_recv(void);
+void microvty_print_prompt(void);
+
+/* to be provided by implementation: tell the code if UART Rx is non-
+ * empty and hence if a subsequent getchar() would return something */
+bool microvty_cb_uart_rx_not_empty(void);

libcommon/src/iob_stm32_blocking.c

@@ -35,3 +35,10 @@ static int my_flush(FILE *file)
 static FILE __stdio = FDEV_SETUP_STREAM(my_putc, my_getc, my_flush, _FDEV_SETUP_RW);
 
 FILE *const __iob[3] = { &__stdio, &__stdio, &__stdio };
+
+#include <libcommon/microvty.h>
+
+bool microvty_cb_uart_rx_not_empty(void)
+{
+	return usart_get_flag(stdio_usart, USART_SR_RXNE);
+}

libcommon/src/iob_stm32_nonblocking.c

@@ -89,3 +89,11 @@ static FILE __stdout = FDEV_SETUP_STREAM(my_stdout_putc, NULL, my_stdout_flush,
 static FILE __stderr = FDEV_SETUP_STREAM(my_stderr_putc, NULL, NULL, _FDEV_SETUP_WRITE);
 
 FILE *const __iob[3] = { &__stdin, &__stdout, &__stderr };
+
+
+#include <libcommon/microvty.h>
+
+bool microvty_cb_uart_rx_not_empty(void)
+{
+	return !ringbuf_empty(&inring);
+}

libcommon/src/microvty.c

@@ -0,0 +1,124 @@
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <libcommon/utils.h>
+#include <libcommon/microvty.h>
+
+/* microVTY - small implementation of a limited feature command line interface
+ * (C) 2019 by Harald Welte <laforge@gnumonks.org>
+ *
+ * modelled after libosmovty (part of libosmocore.git), which in turn is a fork
+ * of the command line interface of GNU zebra / quagga.
+ *
+ * microVTY is intended for very small bare-iron microcontroller. It doesn't need
+ * any dynamic allocations/heap, and tries to stay very simplistic to conserve
+ * resources.
+ */
+
+struct microvty_state {
+	const char *prompt;
+	char buf[MICROVTY_CMD_BUF_SIZE];
+	unsigned int buf_idx;
+	const struct microvty_fn *cmd[MICROVTY_MAX_CMD];
+	unsigned int cmd_idx;
+};
+
+static struct microvty_state g_cmds;
+
+/*! register a command with microVTY */
+int microvty_register(const struct microvty_fn *cmd)
+{
+	if (g_cmds.cmd_idx >= ARRAY_SIZE(g_cmds.cmd))
+		return -1;
+	g_cmds.cmd[g_cmds.cmd_idx++] = cmd;
+	return 0;
+}
+
+/*! built-in help command */
+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(void)
+{
+	char *argv[16];
+	unsigned int i;
+	unsigned int argc = 0;
+	char *cur, *saveptr = NULL;
+
+	printf("\r\n");
+	memset(argv, 0, sizeof(argv));
+
+	for (cur = strtok_r(g_cmds.buf, " ", &saveptr); cur; cur = strtok_r(NULL, " ", &saveptr)) {
+		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;
+}
+
+/*! print the prompt to the console (stdout) */
+void microvty_print_prompt(void)
+{
+	printf(g_cmds.prompt);
+}
+
+/*! try to receive characters from the console, dispatching them */
+void microvty_try_recv(void)
+{
+	unsigned int i = 0;
+
+	/* yield CPU after maximum of 10 received characters */
+	while (microvty_cb_uart_rx_not_empty() && (i < 10)) {
+		int c = getchar();
+		if (c < 0)
+			return;
+		if (c == '\r' || c == '\n' || g_cmds.buf_idx >= sizeof(g_cmds.buf)-1) {
+			/* skip empty commands */
+			if (g_cmds.buf_idx == 0)
+				return;
+			cmd_execute();
+			cmd_buf_reset();
+			printf(g_cmds.prompt);
+			return;
+		} else {
+			/* print + append character */
+			putchar(c);
+			cmd_buf_append(c);
+		}
+
+		i++;
+	}
+}
+
+/* initialize microVTY. Should be called once on start-up */
+void microvty_init(const char *prompt)
+{
+	g_cmds.prompt = prompt;
+	microvty_register(&help_cmd);
+}

projects/rfdsatt/Makefile

@@ -41,9 +41,9 @@ OOCD_TARGET     ?= stm32f1x
 ARCH_FLAGS += --specs=/usr/lib/picolibc/arm-none-eabi/picolibc.specs
 
 LIBCOMMON_DIR = ../../libcommon
-CPPFLAGS += -I$(LIBCOMMON_DIR)/include
+CPPFLAGS += -I$(LIBCOMMON_DIR)/include -D_GNU_SOURCE
 vpath %.c $(LIBCOMMON_DIR)/src/
-OBJS += watchdog.o fault.o iob_stm32_nonblocking.o kill.o
+OBJS += watchdog.o fault.o iob_stm32_nonblocking.o kill.o microvty.o
 
 all: elf bin srec
 

projects/rfdsatt/attenuator.c

@@ -6,8 +6,9 @@
 #include <libopencm3/stm32/gpio.h>
 #include <libopencm3/stm32/rcc.h>
 
+#include <libcommon/utils.h>
+
 #include "attenuator.h"
-#include "utils.h"
 
 static const struct attenuator_cfg *g_att_cfg;
 static struct attenuator_state **g_att_state;

projects/rfdsatt/board_rfdsatt_4ch.c

@@ -1,8 +1,9 @@
 
 #include <libopencm3/stm32/gpio.h>
 
+#include <libcommon/utils.h>
+
 #include "attenuator.h"
-#include "utils.h"
 
 #define NUM_CHAN	4
 #define NUM_STAGE	2

projects/rfdsatt/rfdsatt.c

@@ -25,6 +25,7 @@
 #include <libopencm3/cm3/systick.h>
 
 #include <libcommon/iob.h>
+#include <libcommon/microvty.h>
 
 #include <stdio.h>
 
@@ -104,7 +105,7 @@ static void usart_setup(void)
 	usart_set_baudrate(USART1, 115200);
 	usart_set_databits(USART1, 8);
 	usart_set_stopbits(USART1, USART_STOPBITS_1);
-	usart_set_mode(USART1, USART_MODE_TX);
+	usart_set_mode(USART1, USART_MODE_TX_RX);
 	usart_set_parity(USART1, USART_PARITY_NONE);
 	usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
 	/* Finally enable the USART. */
@@ -119,7 +120,7 @@ static void usart_setup(void)
 	usart_set_baudrate(USART2, 115200);
 	usart_set_databits(USART2, 8);
 	usart_set_stopbits(USART2, USART_STOPBITS_1);
-	usart_set_mode(USART2, USART_MODE_TX);
+	usart_set_mode(USART2, USART_MODE_TX_RX);
 	usart_set_parity(USART2, USART_PARITY_NONE);
 	usart_set_flow_control(USART2, USART_FLOWCONTROL_NONE);
 	/* Finally enable the USART. */
@@ -141,12 +142,17 @@ int main(void)
 	iob_init(USART2);
 	i2c_setup();
 	attenuator_init(&board_att_cfg, board_att_st);
+	microvty_init("rfdsat4ch> ");
+
+	printf("Welcome to RFDSATT\r\n");
+	fprintf(stderr, "Welcome to stderr\r\n");
 
 	/* Blink the LED (PB15) on the board with every transmitted byte. */
 	while (1) {
 		int i;
 		gpio_toggle(GPIOB, GPIO15);	/* LED on/off */
-		printf("Hello world\r\n");
+		//printf("Hello world\r\n");
+		microvty_try_recv();
 		for (i = 0; i < 800000; i++)	/* Wait a bit. */
 			__asm__("nop");
 	}