Improve DSU joystick socket portability and linking

Updated CMakeLists.txt to only enable DSU joystick on non-Emscripten targets and use sdl_link_dependency for required network libraries. Enhanced DSU socket creation for better non-blocking support and portability, including FIONBIO and ioctl handling. Added missing socket-related includes for non-Windows platforms in SDL_dsujoystick_driver.c.

Author: danprice142

CMakeLists.txt

@@ -1375,32 +1375,20 @@ if(SDL_JOYSTICK)
       "${SDL3_SOURCE_DIR}/src/joystick/virtual/*.h"
     )
   endif()
-  
+
   # DSU (DualShock UDP) client support
-  if(SDL_DSU_JOYSTICK)
-    # Disable DSU for platforms that don't support UDP sockets
-    if(EMSCRIPTEN)
-      message(STATUS "DSU joystick disabled on Emscripten (no UDP socket support)")
-      set(SDL_DSU_JOYSTICK OFF)
-    else()
-      set(SDL_JOYSTICK_DSU 1)
-      sdl_glob_sources(
-        "${SDL3_SOURCE_DIR}/src/joystick/dsu/*.c"
-        "${SDL3_SOURCE_DIR}/src/joystick/dsu/*.h"
-      )
-      
-      # DSU requires network libraries
-      if(WIN32)
-        sdl_link_dependency(dsu LIBS ws2_32)
-      elseif(HAIKU)
-        sdl_link_dependency(dsu LIBS network)
-      elseif(APPLE)
-        # macOS/iOS have sockets built-in, no extra linking needed
-      elseif(ANDROID)
-        # Android has sockets built-in, no extra linking needed
-      elseif(UNIX)
-        # Other Unix systems typically have sockets built-in
-      endif()
+  if(SDL_DSU_JOYSTICK AND NOT EMSCRIPTEN)
+    set(SDL_JOYSTICK_DSU 1)
+    sdl_glob_sources(
+      "${SDL3_SOURCE_DIR}/src/joystick/dsu/*.c"
+      "${SDL3_SOURCE_DIR}/src/joystick/dsu/*.h"
+    )
+
+    # DSU requires network libraries
+    if(WIN32)
+      sdl_link_dependency(dsu LIBS ws2_32)
+    elseif(HAIKU)
+      sdl_link_dependency(dsu LIBS network)
     endif()
   endif()
 endif()

src/joystick/dsu/SDL_dsujoystick.c

@@ -61,9 +61,9 @@ typedef int socklen_t;
     #include <fcntl.h>
     #include <unistd.h>
     #include <errno.h>
-    #include <sys/ioctl.h>  /* Required for ioctl on Unix-like systems including Haiku */
+    #include <sys/ioctl.h>
     #ifdef __sun
-        #include <sys/filio.h>  /* FIONBIO on Solaris */
+        #include <sys/filio.h>
     #endif
     #define closesocket close
 #endif
@@ -111,6 +111,9 @@ dsu_socket_t DSU_CreateSocket(Uint16 port)
     u_long mode = 1;
 #else
     int flags;
+#if defined(FIONBIO)
+    int nonblock = 1;
+#endif
 #endif
 
     sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
@@ -125,15 +128,19 @@ dsu_socket_t DSU_CreateSocket(Uint16 port)
 #ifdef _WIN32
     ioctlsocket(sock, FIONBIO, &mode);
 #else
-    /* Use ioctl with FIONBIO for better compatibility across Unix-like systems */
-    #ifdef FIONBIO
-        int mode_unix = 1;
-        ioctl(sock, FIONBIO, &mode_unix);
-    #else
-        /* Fallback to fcntl if FIONBIO is not available */
+#if defined(FIONBIO)
+    if (ioctl(sock, FIONBIO, &nonblock) < 0) {
         flags = fcntl(sock, F_GETFL, 0);
+        if (flags != -1) {
+            fcntl(sock, F_SETFL, flags | O_NONBLOCK);
+        }
+    }
+#else
+    flags = fcntl(sock, F_GETFL, 0);
+    if (flags != -1) {
         fcntl(sock, F_SETFL, flags | O_NONBLOCK);
-    #endif
+    }
+#endif
 #endif
 
     /* Bind to client port if specified */