OSX does not have accept4 :(

GNUmakefile

@@ -204,7 +204,7 @@ clean:
 	rm -f *.o *.obj *.a *.lib *.da *.bbg *.bb core t haveip6.h haven2i.h \
 havesl.h haveinline.h iopause.h select.h havekqueue.h haveepoll.h \
 libepoll havesigio.h havebsdsf.h havesendfile.h havescope.h havedevpoll.h \
-dep libsocket havealloca.h haveuint128.h entities.h ent havepread.h \
+dep libsocket havealloca.h haveuint128.h entities.h ent havepread.h haveaccept4.h \
 *.gcda *.gcno
 
 INCLUDES=buffer.h byte.h fmt.h ip4.h ip6.h mmap.h scan.h socket.h str.h stralloc.h \
@@ -337,6 +337,11 @@ select.h: select.h1 select.h2 trysysel.c
 	if $(DIET) $(CCC) $(CFLAGS) -c trysysel.c >/dev/null 2>&1; then cp select.h2 select.h; else cp select.h1 select.h; fi
 	-rm -f trysysel.o
 
+haveaccept4.h: tryaccept4.c
+	-rm -f $@
+	if $(DIET) $(CCC) $(CFLAGS) -c tryaccept4.c >/dev/null 2>&1; then echo "#define HAVE_ACCEPT4"; fi > $@
+	-rm -f tryaccept4.o
+
 libsocket: trysocket.c
 	if $(DIET) $(CCC) $(CFLAGS) -o trysocket trysocket.c >/dev/null 2>&1; then echo ""; else \
 	if $(DIET) $(CCC) $(CFLAGS) -o trysocket trysocket.c -lsocket >/dev/null 2>&1; then echo "-lsocket"; else \
@@ -352,6 +357,8 @@ socket_mchopcount6.o socket_mcjoin6.o socket_mcleave6.o socket_mcloop6.o \
 socket_recv6.o socket_remote6.o socket_sctp6b.o socket_send6.o \
 socket_tcp6b.o socket_tcp6.o socket_udp6.o socket_accept6_flags.o: haveip6.h
 
+socket_accept4_flags.o socket_accept6_flags.o: haveaccept4.h
+
 socket_accept6.o socket_connect6.o socket_local6.o socket_recv6.o \
 socket_remote6.o socket_send6.o socket_accept6_flags.o: havescope.h
 

socket.h

@@ -47,7 +47,11 @@ int socket_accept4_makenonblocking_setcloseonexec(int s,char* ip,uint16* port);
 int socket_accept6_makenonblocking_setcloseonexec(int s,char* ip,uint16* port,uint32* scope_id);
 
 /* These are internal wrappers around accept4, not meant for external use.
- * flags can be SOCK_NONBLOCK or SOCK_CLOEXEC or both (defined in sys/socket.h) */
+ * flags can be SOCKET_NONBLOCK or SOCKET_CLOEXEC or both */
+enum {
+  SOCKET_NONBLOCK=1,
+  SOCKET_CLOEXEC=2,
+};
 int socket_accept4_flags(int s,char* ip,uint16* port, int flags);
 int socket_accept6_flags(int s,char* ip,uint16* port,uint32* scope_id, int flags);
 

socket/socket_accept4_flags.c

@@ -20,6 +20,8 @@
 #include "io_internal.h"
 #endif
 
+#include "haveaccept4.h"
+
 int socket_accept4_flags(int s, char *ip, uint16 *port, int flags) {
   struct sockaddr_in si;
   socklen_t len = sizeof si;
@@ -75,11 +77,15 @@ incoming:
   } else {
 #endif
 
+#ifdef HAVE_ACCEPT4
     static int noaccept4;	// auto initialized to 0
     if (noaccept4)
       fd=-1;
     else {
-      if ((fd=accept4(s,(void*) &si, &len, flags))==-1) {
+      int flg=0;
+      if (flags & SOCKET_NONBLOCK) flg += SOCK_NONBLOCK;
+      if (flags & SOCKET_CLOEXEC) flg += SOCK_CLOEXEC;
+      if ((fd=accept4(s,(void*) &si, &len, flg))==-1) {
 	if (errno != ENOSYS)
 	  return -1;
 	// if we get here, fd==-1 && errno==ENOSYS
@@ -87,12 +93,13 @@ incoming:
       }
     }
     if (fd==-1) {
+#endif
       int fl = 0;
       /* if we get here, the kernel did not support accept4. */
       if ((fd=accept(s,(void*) &si,&len))==-1)
 	return -1;
-      if (flags & SOCK_NONBLOCK) fl |= O_NDELAY;
-      if (flags & SOCK_CLOEXEC) fl |= O_CLOEXEC;
+      if (flags & SOCKET_NONBLOCK) fl |= O_NDELAY;
+      if (flags & SOCKET_CLOEXEC) fl |= O_CLOEXEC;
       /* On BSD the accepted socket inherits O_NDELAY and O_CLOEXEC, on
        * Linux it doesn't. accept4 makes this explicit. So for the
        * fallback, make it explicit as well */
@@ -107,7 +114,9 @@ incoming:
 #ifdef __linux__
       }
 #endif
+#ifdef HAVE_ACCEPT4
     }
+#endif
 
 #ifdef __MINGW32__
   }

socket/socket_accept6_flags.c

@@ -25,6 +25,8 @@
 #include "io_internal.h"
 #endif
 
+#include "haveaccept4.h"
+
 int socket_accept6_flags(int s, char* ip, uint16* port, uint32* scope_id, int flags)
 {
 #ifdef LIBC_HAS_IP6
@@ -86,17 +88,22 @@ incoming:
   } else {
 #endif
 
+#ifdef HAVE_ACCEPT4
     static int noaccept4;	// auto initialized to 0
     if (noaccept4)
       fd=-1;
     else {
-      if ((fd=accept4(s,(void*) &sa, &dummy, flags))==-1) {
+      int flg=0;
+      if (flags & SOCKET_NONBLOCK) flg += SOCK_NONBLOCK;
+      if (flags & SOCKET_CLOEXEC) flg += SOCK_CLOEXEC;
+      if ((fd=accept4(s,(void*) &sa, &dummy, flg))==-1) {
 	if (errno != ENOSYS)
 	  return -1;
 	noaccept4=1;
       }
     }
     if (fd==-1) {
+#endif
       int fl = 0;
       fd = accept(s, (struct sockaddr *) &sa, &dummy);
       if (fd == -1)
@@ -117,7 +124,9 @@ incoming:
 #ifdef __linux__
       }
 #endif
+#ifdef HAVE_ACCEPT4
     }
+#endif
 #ifdef __MINGW32__
   }
 #endif

tryaccept4.c

@@ -0,0 +1,10 @@
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <stdlib.h>
+
+int main() {
+  accept4(0, NULL, NULL, 0);	// we just want to know if the symbol exists
+  return 0;
+}