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Merged
sbc100 merged 2 commits into from
Jun 19, 2026
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Avoid varargs in socket syscall layer. NFC #27153

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7dd454a
Avoid varargs in socket syscall layer. NFC
kleisauke Jul 23, 2025
ea41972
Automatic rebaseline of codesize expectations. NFC
kleisauke Jun 19, 2026
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2 changes: 1 addition & 1 deletion src/lib/libsigs.js
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Expand Up @@ -269,7 +269,7 @@ sigs = {
__syscall_recvmsg__sig: 'iipiiii',
__syscall_renameat__sig: 'iipip',
__syscall_rmdir__sig: 'ip',
__syscall_sendmsg__sig: 'iipippi',
__syscall_sendmsg__sig: 'iipiiii',
__syscall_sendto__sig: 'iippipi',
__syscall_shutdown__sig: 'iiiiiii',
__syscall_socket__sig: 'iiiiiii',
Expand Down
44 changes: 22 additions & 22 deletions src/lib/libsyscall.js
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Expand Up @@ -351,79 +351,79 @@ var SyscallsLibrary = {
return info;
},
__syscall_socket__deps: ['$SOCKFS'],
__syscall_socket: (domain, type, protocol) => {
__syscall_socket: (domain, type, protocol, u1, u2, u3) => {
var sock = SOCKFS.createSocket(domain, type, protocol);
#if ASSERTIONS
assert(sock.stream.fd < 64); // XXX ? select() assumes socket fd values are in 0..63
#endif
return sock.stream.fd;
},
__syscall_getsockname__deps: ['$getSocketFromFD', '$writeSockaddr', '$DNS'],
__syscall_getsockname: (fd, addr, addrlen, d1, d2, d3) => {
__syscall_getsockname: (fd, addr, len, u1, u2, u3) => {
var sock = getSocketFromFD(fd);
// TODO: sock.saddr should never be undefined, see TODO in websocket_sock_ops.getname
var errno = writeSockaddr(addr, sock.family, DNS.lookup_name(sock.saddr || '0.0.0.0'), sock.sport, addrlen);
var errno = writeSockaddr(addr, sock.family, DNS.lookup_name(sock.saddr || '0.0.0.0'), sock.sport, len);
#if ASSERTIONS
assert(!errno);
#endif
return 0;
},
__syscall_getpeername__deps: ['$getSocketFromFD', '$writeSockaddr', '$DNS'],
__syscall_getpeername: (fd, addr, addrlen, d1, d2, d3) => {

@sbc100 sbc100 Jun 19, 2026

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The man page calls this addrlen. Is there some reason to change it?

@kleisauke kleisauke Jun 19, 2026

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I was trying to sync these syscalls argument names with their corresponding callers:

emscripten/system/lib/libc/musl/src/network/getpeername.c

Lines 4 to 7 in 8484a7b

int getpeername(int fd, struct sockaddr *restrict addr, socklen_t *restrict len)
{
return socketcall(getpeername, fd, addr, len, 0, 0, 0);
}

__syscall_getpeername: (fd, addr, len, u1, u2, u3) => {
var sock = getSocketFromFD(fd);
if (!sock.daddr) {
return -{{{ cDefs.ENOTCONN }}}; // The socket is not connected.
}
var errno = writeSockaddr(addr, sock.family, DNS.lookup_name(sock.daddr), sock.dport, addrlen);
var errno = writeSockaddr(addr, sock.family, DNS.lookup_name(sock.daddr), sock.dport, len);
#if ASSERTIONS
assert(!errno);
#endif
return 0;
},
__syscall_connect__deps: ['$getSocketFromFD', '$getSocketAddress'],
__syscall_connect: (fd, addr, addrlen, d1, d2, d3) => {
__syscall_connect: (fd, addr, len, u1, u2, u3) => {
var sock = getSocketFromFD(fd);
var info = getSocketAddress(addr, addrlen);
var info = getSocketAddress(addr, len);
sock.sock_ops.connect(sock, info.addr, info.port);
return 0;
},
__syscall_shutdown__deps: ['$getSocketFromFD'],
__syscall_shutdown: (fd, how) => {
__syscall_shutdown: (fd, how, u1, u2, u3, u4) => {
getSocketFromFD(fd);
return -{{{ cDefs.ENOSYS }}}; // unsupported feature
},
__syscall_accept4__deps: ['$getSocketFromFD', '$writeSockaddr', '$DNS'],
__syscall_accept4: (fd, addr, addrlen, flags, d1, d2) => {
__syscall_accept4: (fd, addr, len, flags, u1, u2) => {
var sock = getSocketFromFD(fd);
var newsock = sock.sock_ops.accept(sock);
if (addr) {
var errno = writeSockaddr(addr, newsock.family, DNS.lookup_name(newsock.daddr), newsock.dport, addrlen);
var errno = writeSockaddr(addr, newsock.family, DNS.lookup_name(newsock.daddr), newsock.dport, len);
#if ASSERTIONS
assert(!errno);
#endif
}
return newsock.stream.fd;
},
__syscall_bind__deps: ['$getSocketFromFD', '$getSocketAddress'],
__syscall_bind: (fd, addr, addrlen, d1, d2, d3) => {
__syscall_bind: (fd, addr, len, u1, u2, u3) => {
var sock = getSocketFromFD(fd);
var info = getSocketAddress(addr, addrlen);
var info = getSocketAddress(addr, len);
sock.sock_ops.bind(sock, info.addr, info.port);
return 0;
},
__syscall_listen__deps: ['$getSocketFromFD'],
__syscall_listen: (fd, backlog) => {
__syscall_listen: (fd, backlog, u1, u2, u3, u4) => {
var sock = getSocketFromFD(fd);
sock.sock_ops.listen(sock, backlog);
return 0;
},
__syscall_recvfrom__deps: ['$getSocketFromFD', '$writeSockaddr', '$DNS'],
__syscall_recvfrom: (fd, buf, len, flags, addr, addrlen) => {
__syscall_recvfrom: (fd, buf, len, flags, addr, alen) => {
var sock = getSocketFromFD(fd);
var msg = sock.sock_ops.recvmsg(sock, len);
if (!msg) return 0; // socket is closed
if (addr) {
var errno = writeSockaddr(addr, sock.family, DNS.lookup_name(msg.addr), msg.port, addrlen);
var errno = writeSockaddr(addr, sock.family, DNS.lookup_name(msg.addr), msg.port, alen);
#if ASSERTIONS
assert(!errno);
#endif
Expand All @@ -432,18 +432,18 @@ var SyscallsLibrary = {
return msg.buffer.byteLength;
},
__syscall_sendto__deps: ['$getSocketFromFD', '$getSocketAddress'],
__syscall_sendto: (fd, message, length, flags, addr, addr_len) => {
__syscall_sendto: (fd, buf, len, flags, addr, alen) => {
var sock = getSocketFromFD(fd);
if (!addr) {
// send, no address provided
return FS.write(sock.stream, HEAP8, message, length);
return FS.write(sock.stream, HEAP8, buf, len);
}
var dest = getSocketAddress(addr, addr_len);
var dest = getSocketAddress(addr, alen);
// sendto an address
return sock.sock_ops.sendmsg(sock, HEAP8, message, length, dest.addr, dest.port);
return sock.sock_ops.sendmsg(sock, HEAP8, buf, len, dest.addr, dest.port);
},
__syscall_getsockopt__deps: ['$getSocketFromFD'],
__syscall_getsockopt: (fd, level, optname, optval, optlen, d1) => {
__syscall_getsockopt: (fd, level, optname, optval, optlen, unused) => {
var sock = getSocketFromFD(fd);
// Minimal getsockopt aimed at resolving https://github.com/emscripten-core/emscripten/issues/2211
// so only supports SOL_SOCKET with SO_ERROR.
Expand All @@ -458,7 +458,7 @@ var SyscallsLibrary = {
return -{{{ cDefs.ENOPROTOOPT }}}; // The option is unknown at the level indicated.
},
__syscall_sendmsg__deps: ['$getSocketFromFD', '$getSocketAddress'],
__syscall_sendmsg: (fd, message, flags, d1, d2, d3) => {
__syscall_sendmsg: (fd, message, flags, u1, u2, u3) => {
var sock = getSocketFromFD(fd);
var iov = {{{ makeGetValue('message', C_STRUCTS.msghdr.msg_iov, '*') }}};
var num = {{{ makeGetValue('message', C_STRUCTS.msghdr.msg_iovlen, 'i32') }}};
Expand Down Expand Up @@ -489,7 +489,7 @@ var SyscallsLibrary = {
return sock.sock_ops.sendmsg(sock, view, 0, total, addr, port);
},
__syscall_recvmsg__deps: ['$getSocketFromFD', '$writeSockaddr', '$DNS'],
__syscall_recvmsg: (fd, message, flags, d1, d2, d3) => {
__syscall_recvmsg: (fd, message, flags, u1, u2, u3) => {
var sock = getSocketFromFD(fd);
var iov = {{{ makeGetValue('message', C_STRUCTS.msghdr.msg_iov, '*') }}};
var num = {{{ makeGetValue('message', C_STRUCTS.msghdr.msg_iovlen, 'i32') }}};
Expand Down
34 changes: 17 additions & 17 deletions system/include/emscripten/syscalls.h
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Expand Up @@ -98,24 +98,24 @@ int __syscall_utimensat(int dirfd, intptr_t path, intptr_t times, int flags);
int __syscall_fallocate(int fd, int mode, off_t offset, off_t len);
int __syscall_dup3(int fd, int suggestfd, int flags);
int __syscall_pipe2(intptr_t fds, int flags);
int __syscall_recvmmsg(int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...);
int __syscall_recvmmsg(int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, intptr_t timeout);
int __syscall_prlimit64(pid_t pid, int resource, intptr_t new_limit, intptr_t old_limit);
int __syscall_sendmmsg(int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...);
int __syscall_socket(int domain, int type, int protocol, int dummy1, int dummy2, int dummy3);
int __syscall_socketpair(int domain, int type, int protocol, intptr_t fds, int dummy, int dummy2);
int __syscall_bind(int sockfd, intptr_t addr, socklen_t alen, int dummy, int dummy2, int dummy3);
int __syscall_connect(int sockfd, intptr_t addr, socklen_t len, int dummy, int dummy2, int dummy3);
int __syscall_listen(int sockfd, int backlog, int dummy1, int dummy2, int dummy3, int dummy4);
int __syscall_accept4(int sockfd, intptr_t addr, intptr_t addrlen, int flags, int dummy1, int dummy2);
int __syscall_getsockopt(int sockfd, int level, int optname, intptr_t optval, intptr_t optlen, int dummy);
int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, socklen_t optlen, int dummy);
int __syscall_getsockname(int sockfd, intptr_t addr, intptr_t len, int dummy, int dummy2, int dummy3);
int __syscall_getpeername(int sockfd, intptr_t addr, intptr_t len, int dummy, int dummy2, int dummy3);
int __syscall_sendto(int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, socklen_t alen);
int __syscall_sendmsg(int sockfd, intptr_t msg , int flags, intptr_t addr, size_t alen, int dummy);
int __syscall_recvfrom(int sockfd, intptr_t msg, size_t len, int flags, intptr_t addr, intptr_t alen);
int __syscall_recvmsg(int sockfd, intptr_t msg, int flags, int dummy, int dummy2, int dummy3);
int __syscall_shutdown(int sockfd, int how, int dummy, int dummy2, int dummy3, int dummy4);
int __syscall_sendmmsg(int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags);
int __syscall_socket(int domain, int type, int protocol, int unused1, int unused2, int unused3);
int __syscall_socketpair(int domain, int type, int protocol, intptr_t fds, int unused1, int unused2);
int __syscall_bind(int sockfd, intptr_t addr, socklen_t len, int unused1, int unused2, int unused3);
int __syscall_connect(int sockfd, intptr_t addr, socklen_t len, int unused1, int unused2, int unused3);
int __syscall_listen(int sockfd, int backlog, int unused1, int unused2, int unused3, int unused4);
int __syscall_accept4(int sockfd, intptr_t addr, intptr_t len, int flags, int unused1, int unused2);
int __syscall_getsockopt(int sockfd, int level, int optname, intptr_t optval, intptr_t optlen, int unused);
int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, socklen_t optlen, int unused);
int __syscall_getsockname(int sockfd, intptr_t addr, intptr_t len, int unused1, int unused2, int unused3);
int __syscall_getpeername(int sockfd, intptr_t addr, intptr_t len, int unused1, int unused2, int unused3);
int __syscall_sendto(int sockfd, intptr_t buf, size_t len, int flags, intptr_t addr, socklen_t alen);
int __syscall_sendmsg(int sockfd, intptr_t msg, int flags, int unused1, int unused2, int unused3);
int __syscall_recvfrom(int sockfd, intptr_t buf, size_t len, int flags, intptr_t addr, intptr_t alen);
int __syscall_recvmsg(int sockfd, intptr_t msg, int flags, int unused1, int unused2, int unused3);
int __syscall_shutdown(int sockfd, int how, int unused1, int unused2, int unused3, int unused4);

#ifdef __cplusplus
}
Expand Down
10 changes: 5 additions & 5 deletions system/lib/libc/emscripten_syscall_stubs.c
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Expand Up @@ -248,7 +248,7 @@ weak int __syscall_prlimit64(pid_t pid, int resource, intptr_t new_limit, intptr
return 0;
}

weak int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, socklen_t optlen, int dummy) {
weak int __syscall_setsockopt(int sockfd, int level, int optname, intptr_t optval, socklen_t optlen, int unused) {
REPORT(setsockopt);
return -ENOPROTOOPT; // The option is unknown at the level indicated.
}
Expand All @@ -260,7 +260,7 @@ weak pid_t __syscall_wait4(pid_t pid, intptr_t wstatus, int options, int rusage)

UNIMPLEMENTED(acct, (intptr_t filename))
UNIMPLEMENTED(mincore, (intptr_t addr, size_t length, intptr_t vec))
UNIMPLEMENTED(recvmmsg, (int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...))
UNIMPLEMENTED(sendmmsg, (int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, ...))
UNIMPLEMENTED(shutdown, (int sockfd, int how, int dummy, int dummy2, int dummy3, int dummy4))
UNIMPLEMENTED(socketpair, (int domain, int type, int protocol, intptr_t fds, int dummy, int dummy2))
UNIMPLEMENTED(recvmmsg, (int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags, intptr_t timeout))
UNIMPLEMENTED(sendmmsg, (int sockfd, intptr_t msgvec, unsigned int vlen, unsigned int flags))
UNIMPLEMENTED(shutdown, (int sockfd, int how, int unused1, int unused2, int unused3, int unused4))
UNIMPLEMENTED(socketpair, (int domain, int type, int protocol, intptr_t fds, int unused1, int unused2))
52 changes: 34 additions & 18 deletions system/lib/wasmfs/syscalls.cpp
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Expand Up @@ -1723,30 +1723,38 @@ int _munmap_js(

int __syscall_accept4(int sockfd,
intptr_t addr,
intptr_t addrlen,
intptr_t len,
int flags,
int dummy1,
int dummy2) {
int unused1,
int unused2) {
return -ENOSYS;
}

int __syscall_bind(
int sockfd, intptr_t addr, socklen_t alen, int dummy, int dummy2, int dummy3) {
int __syscall_bind(int sockfd,
intptr_t addr,
socklen_t alen,
int unused1,
int unused2,
int unused3) {
return -ENOSYS;
}

int __syscall_connect(
int sockfd, intptr_t addr, socklen_t len, int dummy, int dummy2, int dummy3) {
int __syscall_connect(int sockfd,
intptr_t addr,
socklen_t len,
int unused1,
int unused2,
int unused3) {
return -ENOSYS;
}

int __syscall_socket(
int domain, int type, int protocol, int dummy1, int dummy2, int dummy3) {
int domain, int type, int protocol, int unused1, int unused2, int unused3) {
return -ENOSYS;
}

int __syscall_listen(
int sockfd, int backlog, int dummy1, int dummy2, int dummy3, int dummy4) {
int sockfd, int backlog, int unused1, int unused2, int unused3, int unused4) {
return -ENOSYS;
}

Expand All @@ -1755,22 +1763,30 @@ int __syscall_getsockopt(int sockfd,
int optname,
intptr_t optval,
intptr_t optlen,
int dummy) {
int unused) {
return -ENOSYS;
}

int __syscall_getsockname(
int sockfd, intptr_t addr, intptr_t len, int dummy, int dummy2, int dummy3) {
int __syscall_getsockname(int sockfd,
intptr_t addr,
intptr_t len,
int unused1,
int unused2,
int unused3) {
return -ENOSYS;
}

int __syscall_getpeername(
int sockfd, intptr_t addr, intptr_t len, int dummy, int dummy2, int dummy3) {
int __syscall_getpeername(int sockfd,
intptr_t addr,
intptr_t len,
int unused1,
int unused2,
int unused3) {
return -ENOSYS;
}

int __syscall_sendto(int sockfd,
intptr_t msg,
intptr_t buf,
size_t len,
int flags,
intptr_t addr,
Expand All @@ -1779,12 +1795,12 @@ int __syscall_sendto(int sockfd,
}

int __syscall_sendmsg(
int sockfd, intptr_t msg, int flags, intptr_t addr, size_t alen, int dummy) {
int sockfd, intptr_t msg, int flags, int unused1, int unused2, int unused3) {
return -ENOSYS;
}

int __syscall_recvfrom(int sockfd,
intptr_t msg,
intptr_t buf,
size_t len,
int flags,
intptr_t addr,
Expand All @@ -1793,7 +1809,7 @@ int __syscall_recvfrom(int sockfd,
}

int __syscall_recvmsg(
int sockfd, intptr_t msg, int flags, int dummy, int dummy2, int dummy3) {
int sockfd, intptr_t msg, int flags, int unused1, int unused2, int unused3) {
return -ENOSYS;
}

Expand Down
5 changes: 3 additions & 2 deletions test/codesize/test_codesize_hello_dylink_all.json
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Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
{
"a.out.js": 268255,
"a.out.nodebug.wasm": 587588,
"total": 855843,
"a.out.nodebug.wasm": 587563,
"total": 855818,
"sent": [
"IMG_Init",
"IMG_Load",
Expand Down Expand Up @@ -4092,6 +4092,7 @@
"$__syscall_munmap",
"$__syscall_prlimit64",
"$__syscall_recvmmsg",
"$__syscall_sendmmsg",

@sbc100 sbc100 Jun 19, 2026

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I wonder why this change effects this list?

@kleisauke kleisauke Jun 19, 2026

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Probably due to identical code folding (ICF). At least it saves 25 bytes. :)

@sbc100 sbc100 Jun 19, 2026

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Oh I think maybe some optimization phase was doing duplicate function merging before on this stub, but its no longer identical maybe.

"$__syscall_setdomainname",
"$__syscall_setpgid",
"$__syscall_setpriority",
Expand Down
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