Justin Cormack <justin@street-vision.com> writes:

Here is a small patch to add epoll support to uclibc.

The only thing I am not sure about is what needs to be done (if anything)
to make it work on 2.4/2.2 kernels (are the syscall numbers defined but
give errors when called or not?).

Tested on 2.6, though some other issues prevent more extensive testing at
the minute.

Mike Frysinger:
cleaned up patch and added checks to make sure that the syscall actually
exists, returning ENOSYS in cases where it doesn't.

2 files changed, 66 insertions, 1 deletions

diff --git a/libc/sysdeps/linux/common/Makefile b/libc/sysdeps/linux/common/Makefile
index d1187cb7c..b5ea8d261 100644
--- a/libc/sysdeps/linux/common/Makefile
+++ b/libc/sysdeps/linux/common/Makefile
@@ -24,7 +24,7 @@ CSRC=	__rt_sigtimedwait.c __socketcall.c __syscall_fcntl.c \
 	__syscall_sigaction.c _exit.c access.c acct.c adjtimex.c alarm.c \
 	bdflush.c capget.c capset.c chdir.c chmod.c chown.c chroot.c \
 	close.c cmsg_nxthdr.c creat64.c create_module.c delete_module.c \
-	dup.c dup2.c execve.c fchdir.c fchmod.c fchown.c fdatasync.c \
+	dup.c dup2.c epoll.c execve.c fchdir.c fchmod.c fchown.c fdatasync.c \
 	flock.c fork.c fstat.c fstat64.c fstatfs.c fsync.c ftruncate.c \
 	ftruncate64.c get_kernel_syms.c getcwd.c getdents.c getdents64.c \
 	getdirname.c getdnnm.c getdtablesize.c getegid.c geteuid.c \
diff --git a/libc/sysdeps/linux/common/epoll.c b/libc/sysdeps/linux/common/epoll.c
new file mode 100644
index 000000000..27a9fc526
--- /dev/null
+++ b/libc/sysdeps/linux/common/epoll.c
@@ -0,0 +1,65 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * epoll_create() / epoll_ctl() / epoll_wait() for uClibc
+ *
+ * Copyright (C) 2005 by Erik Andersen <andersen@codepoet.org>
+ *
+ * GNU Library General Public License (LGPL) version 2 or later.
+ */
+
+#include "syscalls.h"
+#include <sys/epoll.h>
+
+/*
+ * epoll_create()
+ */
+#ifdef __NR_epoll_create
+#define __NR___syscall_epoll_create __NR_epoll_create
+static inline _syscall1(int, __syscall_epoll_create, int, size);
+#endif
+
+int epoll_create(int size)
+{
+#ifdef __NR_epoll_create
+	return (__syscall_epoll_create(size));
+#else
+    __set_errno(ENOSYS);
+    return -1;
+#endif
+}
+
+/*
+ * epoll_ctl()
+ */
+#ifdef __NR_epoll_ctl
+#define __NR___syscall_epoll_ctl __NR_epoll_ctl
+static inline _syscall4(int, __syscall_epoll_ctl, int, epfd, int, op, int, fd, struct epoll_event *, event);
+#endif
+
+int epoll_ctl(int epfd, int op, int fd, struct epoll_event *event)
+{
+#ifdef __NR_epoll_ctl
+	return (__syscall_epoll_ctl(epfd, op, fd, event));
+#else
+	__set_errno(ENOSYS);
+	return -1;
+#endif
+}
+
+/*
+ * epoll_wait()
+ */
+#ifdef __NR_epoll_wait
+#define __NR___syscall_epoll_wait __NR_epoll_wait
+static inline _syscall4(int, __syscall_epoll_wait, int, epfd, struct epoll_event *, events, int, maxevents, int, timeout);
+#endif
+
+int epoll_wait(int epfd, struct epoll_event *events, int maxevents, int timeout)
+{
+#ifdef __NR_epoll_wait
+	return (__syscall_epoll_wait(epfd, events, maxevents, timeout));
+#else
+	__set_errno(ENOSYS);
+	return -1;
+#endif
+}