Refactor input to use stdio drivers for Keyboard and TCP

tcp_debug.cpp

@@ -2,16 +2,25 @@
 #include "pico/cyw43_arch.h"
 #include "lwip/tcp.h"
 #include "pico/stdio/driver.h"
+#include "pico/sync.h"
 #include <string.h>
 #include <stdio.h>
 
 #define TCP_PORT 4242
 #define DEBUG_BUF_SIZE 2048
+#define TCP_IN_BUF_SIZE 128
 
 // Circular buffer for debug output
 static char debug_buf[DEBUG_BUF_SIZE];
 static volatile int write_idx = 0;
 static volatile int read_idx = 0;
+
+// Circular buffer for TCP input
+static char tcp_in_buf[TCP_IN_BUF_SIZE];
+static volatile int in_write_idx = 0;
+static volatile int in_read_idx = 0;
+static critical_section_t tcp_in_crit;
+
 static struct tcp_pcb *server_pcb = NULL;
 static struct tcp_pcb *client_pcb = NULL;
 
@@ -39,10 +48,21 @@ static void tcp_out_chars(const char *buf, int len) {
     }
 }
 
+static int tcp_in_chars(char *buf, int len) {
+    int count = 0;
+    critical_section_enter_blocking(&tcp_in_crit);
+    while (count < len && in_read_idx != in_write_idx) {
+        buf[count++] = tcp_in_buf[in_read_idx];
+        in_read_idx = (in_read_idx + 1) % TCP_IN_BUF_SIZE;
+    }
+    critical_section_exit(&tcp_in_crit);
+    return count > 0 ? count : PICO_ERROR_NO_DATA;
+}
+
 static stdio_driver_t tcp_driver = {
     .out_chars = tcp_out_chars,
     .out_flush = NULL,
-    .in_chars = NULL,
+    .in_chars = tcp_in_chars,
 #if PICO_STDIO_ENABLE_CRLF_SUPPORT
     .crlf_enabled = false
 #endif
@@ -84,8 +104,26 @@ static err_t tcp_server_recv(void *arg, struct tcp_pcb *tpcb, struct pbuf *p, er
         printf("TCP debug client disconnected\n");
         return ERR_OK;
     }
-    // We don't expect input, just discard it
-    tcp_recved(tpcb, p->tot_len);
+    
+    // Process received data into input buffer
+    if (p->tot_len > 0) {
+        critical_section_enter_blocking(&tcp_in_crit);
+        struct pbuf *q = p;
+        while (q != NULL) {
+            char *data = (char *)q->payload;
+            for (int i = 0; i < q->len; i++) {
+                int next_write = (in_write_idx + 1) % TCP_IN_BUF_SIZE;
+                if (next_write != in_read_idx) {
+                    tcp_in_buf[in_write_idx] = data[i];
+                    in_write_idx = next_write;
+                }
+            }
+            q = q->next;
+        }
+        critical_section_exit(&tcp_in_crit);
+        tcp_recved(tpcb, p->tot_len);
+    }
+    
     pbuf_free(p);
     return ERR_OK;
 }
@@ -112,6 +150,8 @@ static err_t tcp_server_accept(void *arg, struct tcp_pcb *newpcb, err_t err) {
 bool tcp_debug_init(void) {
     if (server_pcb) return true;
 
+    critical_section_init(&tcp_in_crit);
+
     // Register stdio driver
     stdio_set_driver_enabled(&tcp_driver, true);