POSIX: introduce ppoll

will appear in the next version: https://www.opengroup.org/austin/docs/austin_1110.pdf

Change-Id: I38014ad910881df260f0ec762831491e143328c4
Reviewed-on: https://review.haiku-os.org/c/haiku/+/4099
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

headers/posix/poll.h

@@ -6,6 +6,10 @@
 #define _POLL_H
 
 
+#include <signal.h>
+#include <sys/time.h>
+
+
 typedef unsigned long nfds_t;
 
 struct pollfd {
@@ -29,10 +33,18 @@ struct pollfd {
 #define	POLLNVAL	0x1000		/* invalid file descriptor */
 
 
-extern
 #ifdef __cplusplus
-"C"
+extern "C" {
 #endif
-int poll(struct pollfd *fds, nfds_t numfds, int timeout);
+
+extern int poll(struct pollfd *fds, nfds_t numfds, int timeout);
+extern int ppoll(struct pollfd *fds, nfds_t numfds,
+	const struct timespec *timeout, const sigset_t *sigMask);
+
+#ifdef __cplusplus
+}
+#endif
+
+
 
 #endif /* _POLL_H */

headers/private/kernel/vfs.h

@@ -211,7 +211,8 @@ status_t	_user_access(int fd, const char *path, int mode,
 				bool effectiveUserGroup);
 ssize_t		_user_select(int numfds, fd_set *readSet, fd_set *writeSet,
 				fd_set *errorSet, bigtime_t timeout, const sigset_t *sigMask);
-ssize_t		_user_poll(struct pollfd *fds, int numfds, bigtime_t timeout);
+ssize_t		_user_poll(struct pollfd *fds, int numfds, bigtime_t timeout,
+				const sigset_t *sigMask);
 int			_user_open_attr_dir(int fd, const char *path,
 				bool traverseLeafLink);
 ssize_t		_user_read_attr(int fd, const char *attribute, off_t pos,

headers/private/system/syscalls.h

@@ -286,7 +286,7 @@ extern ssize_t		_kern_select(int numfds, struct fd_set *readSet,
 						struct fd_set *writeSet, struct fd_set *errorSet,
 						bigtime_t timeout, const sigset_t *sigMask);
 extern ssize_t		_kern_poll(struct pollfd *fds, int numFDs,
-						bigtime_t timeout);
+						bigtime_t timeout, const sigset_t *sigMask);
 
 extern int			_kern_open_attr_dir(int fd, const char *path,
 						bool traverseLeafLink);

src/system/kernel/wait_for_objects.cpp

@@ -550,7 +550,8 @@ common_select(int numFDs, fd_set *readSet, fd_set *writeSet, fd_set *errorSet,
 
 
 static int
-common_poll(struct pollfd *fds, nfds_t numFDs, bigtime_t timeout, bool kernel)
+common_poll(struct pollfd *fds, nfds_t numFDs, bigtime_t timeout,
+	const sigset_t *sigMask, bool kernel)
 {
 	// allocate sync object
 	select_sync* sync;
@@ -580,11 +581,26 @@ common_poll(struct pollfd *fds, nfds_t numFDs, bigtime_t timeout, bool kernel)
 		}
 	}
 
+	// set new signal mask
+	sigset_t oldSigMask;
+	if (sigMask != NULL) {
+		sigprocmask(SIG_SETMASK, sigMask, &oldSigMask);
+		if (!kernel) {
+			Thread *thread = thread_get_current_thread();
+			thread->old_sig_block_mask = oldSigMask;
+			thread->flags |= THREAD_FLAGS_OLD_SIGMASK;
+		}
+	}
+
 	if (!invalid) {
 		status = acquire_sem_etc(sync->sem, 1,
 			B_CAN_INTERRUPT | (timeout >= 0 ? B_ABSOLUTE_TIMEOUT : 0), timeout);
 	}
 
+	// restore the old signal mask
+	if (sigMask != NULL && kernel)
+		sigprocmask(SIG_SETMASK, &oldSigMask, NULL);
+
 	// deselect file descriptors
 
 	for (uint32 i = 0; i < numFDs; i++) {
@@ -892,12 +908,13 @@ _kern_select(int numFDs, fd_set *readSet, fd_set *writeSet, fd_set *errorSet,
 
 
 ssize_t
-_kern_poll(struct pollfd *fds, int numFDs, bigtime_t timeout)
+_kern_poll(struct pollfd *fds, int numFDs, bigtime_t timeout,
+	const sigset_t *sigMask)
 {
 	if (timeout >= 0)
 		timeout += system_time();
 
-	return common_poll(fds, numFDs, timeout, true);
+	return common_poll(fds, numFDs, timeout, sigMask, true);
 }
 
 
@@ -1017,10 +1034,12 @@ err:
 
 
 ssize_t
-_user_poll(struct pollfd *userfds, int numFDs, bigtime_t timeout)
+_user_poll(struct pollfd *userfds, int numFDs, bigtime_t timeout,
+	const sigset_t *userSigMask)
 {
-	struct pollfd *fds;
-	size_t bytes;
+	struct pollfd *fds = NULL;
+	size_t bytes = 0;
+	sigset_t sigMask;
 	int result;
 
 	if (timeout >= 0) {
@@ -1033,28 +1052,33 @@ _user_poll(struct pollfd *userfds, int numFDs, bigtime_t timeout)
 	if (numFDs < 0)
 		return B_BAD_VALUE;
 
-	if (numFDs == 0) {
-		// special case: no FDs
-		return common_poll(NULL, 0, timeout, false);
+	if (numFDs != 0) {
+
+		if (!check_max_fds(numFDs))
+			return B_BAD_VALUE;
+
+		if (userfds == NULL || !IS_USER_ADDRESS(userfds))
+			return B_BAD_ADDRESS;
+
+		fds = (struct pollfd *)malloc(bytes = numFDs * sizeof(struct pollfd));
+		if (fds == NULL)
+			return B_NO_MEMORY;
+
+		if (user_memcpy(fds, userfds, bytes) < B_OK) {
+			result = B_BAD_ADDRESS;
+			goto err;
+		}
 	}
 
-	if (!check_max_fds(numFDs))
-		return B_BAD_VALUE;
-
-	// copy parameters
-	if (userfds == NULL || !IS_USER_ADDRESS(userfds))
-		return B_BAD_ADDRESS;
-
-	fds = (struct pollfd *)malloc(bytes = numFDs * sizeof(struct pollfd));
-	if (fds == NULL)
-		return B_NO_MEMORY;
-
-	if (user_memcpy(fds, userfds, bytes) < B_OK) {
+	if (userSigMask != NULL
+		&& (!IS_USER_ADDRESS(userSigMask)
+			|| user_memcpy(&sigMask, userSigMask, sizeof(sigMask)) < B_OK)) {
 		result = B_BAD_ADDRESS;
 		goto err;
 	}
 
-	result = common_poll(fds, numFDs, timeout, false);
+	result = common_poll(fds, numFDs, timeout,
+		userSigMask != NULL ? &sigMask : NULL, false);
 
 	// copy back results
 	if (numFDs > 0 && user_memcpy(userfds, fds, bytes) != 0) {

src/system/libroot/posix/poll.c

@@ -15,8 +15,30 @@
 #include <syscalls.h>
 
 
+int __ppoll(struct pollfd *fds, nfds_t numfds, const struct timespec *tv,
+	const sigset_t *sigMask);
+
 int
 poll(struct pollfd *fds, nfds_t numfds, int timeout)
 {
-	RETURN_AND_SET_ERRNO_TEST_CANCEL(_kern_poll(fds, numfds, timeout * 1000LL));
+	RETURN_AND_SET_ERRNO_TEST_CANCEL(_kern_poll(fds, numfds, timeout * 1000LL,
+		NULL));
 }
+
+
+int
+__ppoll(struct pollfd *fds, nfds_t numfds, const struct timespec *tv,
+	const sigset_t *sigMask)
+{
+	int status;
+	bigtime_t timeout = -1LL;
+	if (tv)
+		timeout = tv->tv_sec * 1000000LL + tv->tv_nsec / 1000LL;
+
+	status = _kern_poll(fds, numfds, timeout, sigMask);
+
+	RETURN_AND_SET_ERRNO_TEST_CANCEL(status);
+}
+
+
+B_DEFINE_WEAK_ALIAS(__ppoll, ppoll);