LibC+Kernel: Implement ppoll

ppoll() is similar() to poll(), but it takes its timeout
as timespec instead of as int, and it takes an additional
sigmask parameter.

Change the sys$poll parameters to match ppoll() and implement
poll() in terms of ppoll().

2 files changed, 20 insertions, 3 deletions

diff --git a/Libraries/LibC/poll.cpp b/Libraries/LibC/poll.cpp
index 46f2fdf49f..256c4528f4 100644
--- a/Libraries/LibC/poll.cpp
+++ b/Libraries/LibC/poll.cpp
@@ -27,12 +27,25 @@
 #include <Kernel/Syscall.h>
 #include <errno.h>
 #include <poll.h>
+#include <sys/time.h>
 
 extern "C" {
 
-int poll(struct pollfd* fds, int nfds, int timeout)
+int poll(pollfd* fds, nfds_t nfds, int timeout_ms)
 {
-    int rc = syscall(SC_poll, fds, nfds, timeout);
+    timespec timeout;
+    timespec* timeout_ts = &timeout;
+    if (timeout_ms < 0)
+        timeout_ts = nullptr;
+    else
+        timeout = { timeout_ms / 1000, (timeout_ms % 1000) * 1'000'000 };
+    return ppoll(fds, nfds, timeout_ts, nullptr);
+}
+
+int ppoll(pollfd* fds, nfds_t nfds, const timespec* timeout, const sigset_t* sigmask)
+{
+    Syscall::SC_poll_params params { fds, nfds, timeout, sigmask };
+    int rc = syscall(SC_poll, &params);
     __RETURN_WITH_ERRNO(rc, rc, -1);
 }
 }
diff --git a/Libraries/LibC/poll.h b/Libraries/LibC/poll.h
index 051357249a..af0ff254c5 100644
--- a/Libraries/LibC/poll.h
+++ b/Libraries/LibC/poll.h
@@ -26,6 +26,7 @@
 
 #pragma once
 
+#include <signal.h>
 #include <sys/cdefs.h>
 
 __BEGIN_DECLS
@@ -43,6 +44,9 @@ struct pollfd {
     short revents;
 };
 
-int poll(struct pollfd* fds, int nfds, int timeout);
+typedef unsigned nfds_t;
+
+int poll(struct pollfd* fds, nfds_t nfds, int timeout);
+int ppoll(struct pollfd* fds, nfds_t nfds, const struct timespec* timeout, const sigset_t* sigmask);
 
 __END_DECLS