add serial hander and info command

main.c

@@ -1,10 +1,14 @@
-#define TCP_PORT 80
+#ifndef NDEBUG
 #define DEBUG_printf printf
+#else
+#define DEBUG_printf
+#endif
 
+#include "secret.h"
 #include "pico_lib.h"
 #include "bmc_handler.h"
 #include "http_serv.h"
-#include "secret.h"
+#include "serial_handler.h"
 
 void set_host_name(const char * hostname) {
 	cyw43_arch_lwip_begin();
@@ -22,6 +26,8 @@ int main() {
 		return 1;
 	}
 
+	serial_handler_init();
+
 	cyw43_arch_enable_sta_mode();
 	set_host_name(BMC_HOSTNAME);
 	DEBUG_printf("[INIT] [OK ] Set hostname to %s\n", BMC_HOSTNAME);
@@ -46,6 +52,7 @@ int main() {
 
 	bmc_handler_deinit();
 	http_serv_deinit();
+	serial_handler_deinit();
 	cyw43_arch_deinit();
 	return 0;
 }

serial_handler.h

@@ -0,0 +1,103 @@
+#ifndef SERIAL_HANDLER_H
+#define SERIAL_HANDLER_H
+
+#define INPUT_BUFFER_SIZE 1024
+
+char * input_buffer;
+int write_offset;
+
+bool inc_write_offset () {
+	if (write_offset < INPUT_BUFFER_SIZE - 1) {
+		write_offset++;
+		return true;
+	}
+	else {
+		DEBUG_printf("[SER ] [ERR] write_offset overflow\n");
+		return false;
+	}	
+}
+
+bool dec_write_offset () {
+	if (write_offset > 0) {
+		write_offset--;
+		return true;
+	}
+	else {
+		DEBUG_printf("[SER ] [ERR] write_offset underflow\n");
+		return false;
+	}
+}
+
+void rst_write_offset () {
+	write_offset = 0;
+}
+
+void handle_return () {
+	if (strcmp(input_buffer, "") == 0) {
+		return;
+	}
+	else if (strcmp(input_buffer, "info") == 0) {
+		printf("Network: %s\nHostname: %s\nAddress: %s\nHTTP Port: %i\n", WIFI_SSID, BMC_HOSTNAME, ip_ntoa(netif_ip4_addr(&cyw43_state.netif[CYW43_ITF_STA])), HTTP_PORT);
+	}
+	else {
+		printf("Unknown command: %s\n", input_buffer);
+	}
+}
+
+// interrupt code adapted from: https://github.com/raspberrypi/pico-examples/blob/eca13acf57916a0bd5961028314006983894fc84/pico_w/wifi/iperf/picow_iperf.c
+// and fixed using the suggestion from: https://github.com/raspberrypi/pico-examples/issues/474
+
+// final interrupt callback which consumes the keypress
+// when it recieves a character, echo back to the console 
+void key_pressed_worker_func(async_context_t * context, async_when_pending_worker_t * worker) {
+	int key;
+	while ((key = getchar_timeout_us(0)) > 0) {
+		if (key == 0x08 || key == 0x7F) { // backspace & delete
+			if (dec_write_offset()) {
+				printf("\b \b");
+				input_buffer[write_offset] = 0;
+			}
+		}
+		else if (key == '\r' || key == '\n') { // return
+			printf("\n");
+			input_buffer[write_offset] = 0;
+			handle_return();
+			rst_write_offset();
+		}
+		else if (32 <= key && key <= 126) { // printable characters
+			printf("%c", key);
+			input_buffer[write_offset] = key;
+			inc_write_offset();
+		}
+		else if (key == 27) { // escape & escape codes
+			while (getchar_timeout_us(0) > 0) {}
+			break;
+		}
+		else {	// other unhandled key
+			DEBUG_printf("[SER ] [ERR] recieved unhandled key [%i]\n", key);
+		}
+	}
+}
+
+static async_when_pending_worker_t key_pressed_worker = {
+	.do_work = key_pressed_worker_func
+};
+
+// because of stdio_set_chars_available_callback implementation, stdlib mutex is locked here so schedule another callback
+void key_pressed_func(void * param) {
+	async_context_set_work_pending((async_context_t *)param, &key_pressed_worker);
+}
+
+// init serial handler
+void serial_handler_init () {
+	input_buffer = malloc(INPUT_BUFFER_SIZE * sizeof(char));
+	async_context_add_when_pending_worker(cyw43_arch_async_context(), &key_pressed_worker);
+	stdio_set_chars_available_callback(key_pressed_func, cyw43_arch_async_context());
+}
+
+void serial_handler_deinit () {
+	free(input_buffer);
+	input_buffer = NULL;
+}
+
+#endif