Stub out SYS_recvmmsg syscall

Author: jgravelle-google

src/library_syscall.js

@@ -1250,6 +1250,12 @@ var SyscallsLibrary = {
     var stream = SYSCALLS.getStreamFromFD(), iov = SYSCALLS.get(), iovcnt = SYSCALLS.get(), offset = SYSCALLS.get();
     return SYSCALLS.doWritev(stream, iov, iovcnt, offset);
   },
+  __syscall337: function(which, varargs) { // recvmmsg
+#if SYSCALL_DEBUG
+    Module.printErr('warning: ignoring SYS_recvmmsg');
+#endif
+    return 0;
+  },
   __syscall340: function(which, varargs) { // prlimit64
     var pid = SYSCALLS.get(), resource = SYSCALLS.get(), new_limit = SYSCALLS.get(), old_limit = SYSCALLS.get();
     if (old_limit) { // just report no limits
@@ -1602,6 +1608,7 @@ if (SYSCALL_DEBUG) {
     SYS_inotify_init1: 332,
     SYS_preadv: 333,
     SYS_pwritev: 334,
+    SYS_recvmmsg: 337,
     SYS_prlimit64: 340,
     SYS_name_to_handle_at: 341,
     SYS_open_by_handle_at: 342,

system/lib/libc/musl/arch/emscripten/bits/syscall.h

@@ -333,6 +333,7 @@
 #define __NR_inotify_init1	332
 #define __NR_preadv		333
 #define __NR_pwritev		334
+#define __NR_recvmmsg		337
 #define __NR_prlimit64		340
 #define __NR_name_to_handle_at	341
 #define __NR_open_by_handle_at	342
@@ -683,6 +684,7 @@
 #define SYS_inotify_init1	332
 #define SYS_preadv		333
 #define SYS_pwritev		334
+#define SYS_recvmmsg		337
 #define SYS_prlimit64		340
 #define SYS_name_to_handle_at	341
 #define SYS_open_by_handle_at	342

system/lib/libc/musl/arch/emscripten/syscall_arch.h

@@ -141,6 +141,7 @@ long __syscall330(int which, ...);
 long __syscall331(int which, ...);
 long __syscall333(int which, ...);
 long __syscall334(int which, ...);
+long __syscall337(int which, ...);
 long __syscall340(int which, ...);
 long __syscall345(int which, ...);
 

system/lib/libc/musl/src/network/recvmmsg.c

@@ -11,9 +11,5 @@ int recvmmsg(int fd, struct mmsghdr *msgvec, unsigned int vlen, unsigned int fla
 	for (i = vlen; i; i--, mh++)
 		mh->msg_hdr.__pad1 = mh->msg_hdr.__pad2 = 0;
 #endif
-#ifndef __EMSCRIPTEN__
 	return syscall_cp(SYS_recvmmsg, fd, msgvec, vlen, flags, timeout);
-#else
-    return -1;
-#endif
 }