Add epoll headers and syscall stubs

src/lib/libsigs.js

@@ -237,6 +237,9 @@ sigs = {
   __syscall_connect__sig: 'iipiiii',
   __syscall_dup__sig: 'ii',
   __syscall_dup3__sig: 'iiii',
+  __syscall_epoll_create1__sig: 'ii',
+  __syscall_epoll_ctl__sig: 'iiiip',
+  __syscall_epoll_pwait__sig: 'iipiipp',
   __syscall_faccessat__sig: 'iipii',
   __syscall_fallocate__sig: 'iiijj',
   __syscall_fchdir__sig: 'ii',

src/lib/libsyscall.js

@@ -715,6 +715,13 @@ var SyscallsLibrary = {
   __syscall_poll_nonblocking: (fds, nfds) => {
     return doPoll(fds, nfds, 0, undefined);
   },
+  // epoll is not yet implemented in the legacy (non-WASMFS) JS syscall layer.
+  __syscall_epoll_create1__nothrow: true,
+  __syscall_epoll_create1: (flags) => -{{{ cDefs.ENOSYS }}},
+  __syscall_epoll_ctl__nothrow: true,
+  __syscall_epoll_ctl: (epfd, op, fd, ev) => -{{{ cDefs.ENOSYS }}},
+  __syscall_epoll_pwait__nothrow: true,
+  __syscall_epoll_pwait: (epfd, ev, maxevents, timeout, sigmask, sigsetsize) => -{{{ cDefs.ENOSYS }}},
   __syscall_getcwd__deps: ['$lengthBytesUTF8', '$stringToUTF8'],
   __syscall_getcwd: (buf, size) => {
     if (size === 0) return -{{{ cDefs.EINVAL }}};

system/include/emscripten/syscalls.h

@@ -9,6 +9,7 @@
 
 #include <poll.h>
 #include <stdint.h>
+#include <sys/epoll.h>
 #include <sys/resource.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
@@ -120,6 +121,9 @@ int __syscall_sendmsg(int sockfd, const struct msghdr *msg, int flags, int unuse
 int __syscall_recvfrom(int sockfd, void *buf, size_t len, int flags, struct sockaddr *addr, socklen_t *alen);
 int __syscall_recvmsg(int sockfd, struct msghdr *msg, int flags, int unused1, int unused2, int unused3);
 int __syscall_shutdown(int sockfd, int how, int unused1, int unused2, int unused3, int unused4);
+int __syscall_epoll_create1(int flags);
+int __syscall_epoll_ctl(int epfd, int op, int fd, struct epoll_event *ev);
+int __syscall_epoll_pwait(int epfd, struct epoll_event *ev, int maxevents, int timeout, const sigset_t *sigmask, size_t sigsetsize);
 
 #ifdef __cplusplus
 }

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

@@ -86,3 +86,6 @@
 #define SYS_recvfrom		__syscall_recvfrom
 #define SYS_recvmsg		__syscall_recvmsg
 #define SYS_shutdown		__syscall_shutdown
+#define SYS_epoll_create1	__syscall_epoll_create1
+#define SYS_epoll_ctl		__syscall_epoll_ctl
+#define SYS_epoll_pwait		__syscall_epoll_pwait

system/lib/libc/musl/include/sys/epoll.h

@@ -0,0 +1,81 @@
+#ifndef	_SYS_EPOLL_H
+#define	_SYS_EPOLL_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+
+#define __NEED_sigset_t
+
+#include <bits/alltypes.h>
+
+#define EPOLL_CLOEXEC O_CLOEXEC
+#define EPOLL_NONBLOCK O_NONBLOCK
+
+enum EPOLL_EVENTS { __EPOLL_DUMMY };
+#define EPOLLIN 0x001
+#define EPOLLPRI 0x002
+#define EPOLLOUT 0x004
+#define EPOLLRDNORM 0x040
+#define EPOLLNVAL 0x020
+#define EPOLLRDBAND 0x080
+#define EPOLLWRNORM 0x100
+#define EPOLLWRBAND 0x200
+#define EPOLLMSG 0x400
+#define EPOLLERR 0x008
+#define EPOLLHUP 0x010
+#define EPOLLRDHUP 0x2000
+#define EPOLLEXCLUSIVE (1U<<28)
+#define EPOLLWAKEUP (1U<<29)
+#define EPOLLONESHOT (1U<<30)
+#define EPOLLET (1U<<31)
+
+#define EPOLL_CTL_ADD 1
+#define EPOLL_CTL_DEL 2
+#define EPOLL_CTL_MOD 3
+
+typedef union epoll_data {
+	void *ptr;
+	int fd;
+	uint32_t u32;
+	uint64_t u64;
+} epoll_data_t;
+
+struct epoll_event {
+	uint32_t events;
+	epoll_data_t data;
+}
+#ifdef __x86_64__
+__attribute__ ((__packed__))
+#endif
+;
+
+struct epoll_params {
+	uint32_t busy_poll_usecs;
+	uint16_t busy_poll_budget;
+	uint8_t prefer_busy_poll;
+
+	uint8_t __pad;
+};
+
+#define EPOLL_IOC_TYPE 0x8A
+#define EPIOCSPARAMS _IOW(EPOLL_IOC_TYPE, 0x01, struct epoll_params)
+#define EPIOCGPARAMS _IOR(EPOLL_IOC_TYPE, 0x02, struct epoll_params)
+
+int epoll_create(int);
+int epoll_create1(int);
+int epoll_ctl(int, int, int, struct epoll_event *);
+int epoll_wait(int, struct epoll_event *, int, int);
+int epoll_pwait(int, struct epoll_event *, int, int, const sigset_t *);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* sys/epoll.h */

system/lib/update_musl.py

@@ -42,7 +42,6 @@
   'aio.h',
   'auxv.h',
   'cachectl.h',
-  'epoll.h',
   'eventfd.h',
   'fanotify.h',
   'fsuid.h',

system/lib/wasmfs/syscalls.cpp

@@ -1846,4 +1846,20 @@ int __syscall_fadvise64(int fd, off_t offset, off_t len, int advice) {
   return 0;
 }
 
+// epoll is implemented in the legacy (non-WASMFS) JS syscall layer only.
+int __syscall_epoll_create1(int flags) { return -ENOSYS; }
+
+int __syscall_epoll_ctl(int epfd, int op, int fd, struct epoll_event* ev) {
+  return -ENOSYS;
+}
+
+int __syscall_epoll_pwait(int epfd,
+                          struct epoll_event* ev,
+                          int maxevents,
+                          int timeout,
+                          const sigset_t* sigmask,
+                          size_t sigsetsize) {
+  return -ENOSYS;
+}
+
 } // extern "C"

test/codesize/test_codesize_hello_dylink_all.json

@@ -1,7 +1,7 @@
 {
-  "a.out.js": 268445,
-  "a.out.nodebug.wasm": 587520,
-  "total": 855965,
+  "a.out.js": 268603,
+  "a.out.nodebug.wasm": 587900,
+  "total": 856503,
   "sent": [
     "IMG_Init",
     "IMG_Load",
@@ -222,6 +222,9 @@
     "__syscall_connect",
     "__syscall_dup",
     "__syscall_dup3",
+    "__syscall_epoll_create1",
+    "__syscall_epoll_ctl",
+    "__syscall_epoll_pwait",
     "__syscall_faccessat",
     "__syscall_fallocate",
     "__syscall_fchdir",
@@ -1744,6 +1747,9 @@
     "env.__syscall_connect",
     "env.__syscall_dup",
     "env.__syscall_dup3",
+    "env.__syscall_epoll_create1",
+    "env.__syscall_epoll_ctl",
+    "env.__syscall_epoll_pwait",
     "env.__syscall_faccessat",
     "env.__syscall_fallocate",
     "env.__syscall_fchdir",
@@ -2596,6 +2602,11 @@
     "endpwent",
     "endservent",
     "environ",
+    "epoll_create",
+    "epoll_create1",
+    "epoll_ctl",
+    "epoll_pwait",
+    "epoll_wait",
     "erand48",
     "erf",
     "erfc",
@@ -4460,6 +4471,11 @@
     "$emutls_key_destructor",
     "$encrypt",
     "$endmntent",
+    "$epoll_create",
+    "$epoll_create1",
+    "$epoll_ctl",
+    "$epoll_pwait",
+    "$epoll_wait",
     "$erand48",
     "$erf",
     "$erfc",

tools/native_sigs.py

@@ -419,6 +419,8 @@
   '__syscall_chdir': '_p',
   '__syscall_chmod': '_p_',
   '__syscall_connect': '__p____',
+  '__syscall_epoll_ctl': '____p',
+  '__syscall_epoll_pwait': '__p__pp',
   '__syscall_faccessat': '__p__',
   '__syscall_fchmodat2': '__p__',
   '__syscall_fchownat': '__p___',
@@ -872,6 +874,9 @@
   'emscripten_wget': '_pp',
   'encrypt': '_p_',
   'endmntent': '_p',
+  'epoll_ctl': '____p',
+  'epoll_pwait': '__p__p',
+  'epoll_wait': '__p__',
   'erand48': '_p',
   'erfcl': '_p__',
   'erfl': '_p__',

tools/system_libs.py

@@ -1338,7 +1338,7 @@ def get_files(self):
 
     libc_files += files_in_path(
         path='system/lib/libc/musl/src/linux',
-        filenames=['getdents.c', 'gettid.c', 'utimes.c', 'statx.c', 'wait4.c', 'wait3.c'])
+        filenames=['getdents.c', 'gettid.c', 'utimes.c', 'statx.c', 'wait4.c', 'wait3.c', 'epoll.c'])
 
     libc_files += files_in_path(
         path='system/lib/libc/musl/src/malloc',