working noVNC

wssshd2/websocket_protocol.c

@@ -23,6 +23,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include <string.h>  // for strerror
+#include <fcntl.h>
 #include <openssl/sha.h>
 #include <openssl/ssl.h>
 #include "websocket_protocol.h"
@@ -588,10 +589,19 @@ bool ws_send_binary_frame(ws_connection_t *conn, const void *data, size_t len, b
         memcpy(frame + header_len, data, len);
     }
 
-    // Send frame with partial write handling and retry logic
+    // Send frame - for WebSocket binary frames, we need to send atomically
+    // Temporarily set socket to blocking mode to ensure complete frame transmission
+    int original_flags = -1;
+    if (!conn->ssl) {
+        original_flags = fcntl(conn->sock_fd, F_GETFL, 0);
+        if (original_flags != -1) {
+            fcntl(conn->sock_fd, F_SETFL, original_flags & ~O_NONBLOCK);
+        }
+    }
+
     int total_written = 0;
     int retry_count = 0;
-    const int max_retries = 5;
+    const int max_retries = 10;
 
     if (debug) printf("[WS-BINARY] Sending frame of total length %zu\n", frame_len);
 
@@ -619,8 +629,8 @@ bool ws_send_binary_frame(ws_connection_t *conn, const void *data, size_t len, b
             written = write(conn->sock_fd, frame + total_written, to_write);
             if (written < 0) {
                 if (errno == EAGAIN || errno == EWOULDBLOCK) {
-                    // Non-blocking socket, try again
-                    if (debug) printf("[WS-BINARY] Socket would block, retrying\n");
+                    // Should not happen in blocking mode, but handle anyway
+                    if (debug) printf("[WS-BINARY] Socket would block in blocking mode, retrying\n");
                     retry_count++;
                     usleep(1000); // Short delay before retry
                     continue;
@@ -643,6 +653,11 @@ bool ws_send_binary_frame(ws_connection_t *conn, const void *data, size_t len, b
         if (debug) printf("[WS-BINARY] Wrote %d bytes, total written: %d/%zu\n", written, total_written, frame_len);
     }
 
+    // Restore original socket flags
+    if (!conn->ssl && original_flags != -1) {
+        fcntl(conn->sock_fd, F_SETFL, original_flags);
+    }
+
     if (total_written != (int)frame_len) {
         if (debug) printf("[WS-BINARY] Failed to write complete frame: %d/%zu\n", total_written, frame_len);
         free(frame);