1 files changed, 49 insertions, 8 deletions

diff --git a/lib/libpthread/uthread/uthread_closefrom.c b/lib/libpthread/uthread/uthread_closefrom.c
index d80c0cff21d..62176ec2d24 100644
--- a/lib/libpthread/uthread/uthread_closefrom.c
+++ b/lib/libpthread/uthread/uthread_closefrom.c
@@ -1,10 +1,11 @@
-/* $OpenBSD: uthread_closefrom.c,v 1.2 2006/09/22 19:04:33 kurt Exp $ */
+/* $OpenBSD: uthread_closefrom.c,v 1.3 2006/09/26 14:18:28 kurt Exp $ */
 
 /* PUBLIC DOMAIN: No Rights Reserved. Marco S Hyman <marc@snafu.org> */
 
 #include <sys/stat.h>
 
 #include <errno.h>
+#include <stdlib.h>
 #include <pthread.h>
 #include <unistd.h>
 
@@ -13,9 +14,10 @@
 int
 closefrom(int fd)
 {
-	int ret;
+	int ret = 0;
 	int safe_fd;
 	int lock_fd;
+	int *flags;
 
 	_thread_enter_cancellation_point();
 	
@@ -33,13 +35,52 @@ closefrom(int fd)
 		for (safe_fd++; fd < safe_fd; fd++)
 			close(fd);
 
-		/* Reset flags and clean up the fd table for fds to close */
-		for (lock_fd = fd; lock_fd < _thread_dtablesize; lock_fd++)
-			if (_thread_fd_table[lock_fd] != NULL)
-				_thread_fd_table_remove(lock_fd);
+		flags = calloc((size_t)_thread_dtablesize, sizeof *flags);
+		if (flags == NULL) {
+			/* use calloc errno */
+			ret = -1;
+		} else {
+			/* Lock and record all fd entries */
+			for (lock_fd = fd; lock_fd < _thread_dtablesize; lock_fd++) {
+				if (_thread_fd_table[lock_fd] != NULL &&
+			   	 _thread_fd_table[lock_fd]->state != FD_ENTRY_CLOSED) {
+					ret = _FD_LOCK(lock_fd, FD_RDWR_CLOSE, NULL);
+					if (ret != -1)
+						flags[lock_fd] = 1;
+					else
+						break;
+				}
+			}
 
-		/* Now let the system do its thing */
-		ret = _thread_sys_closefrom(fd);
+			if (ret != -1) {
+				/*
+				 * Close the entries and reset the non-bocking
+				 * flag when needed.
+				 */
+				for (lock_fd = fd; lock_fd < _thread_dtablesize; lock_fd++) {
+					if (flags[lock_fd] != NULL) {
+						_thread_fd_entry_close(lock_fd);
+					}
+				}
+				/*
+				 * Now let the system do its thing. It is not practical
+				 * to try to prevent races with other threads that can
+				 * create new file descriptors. We just have to assume
+				 * the application is well behaved when using closefrom.
+				 */
+				ret = _thread_sys_closefrom(fd);
+			}
+
+			/*
+			 * Unlock any locked entries.
+			 */
+			for (lock_fd = fd; lock_fd < _thread_dtablesize; lock_fd++) {
+				if (flags[lock_fd] != NULL) {
+					_FD_UNLOCK(lock_fd, FD_RDWR_CLOSE);
+				}
+			}
+			free(flags);
+		}
 	}
 
 	_thread_leave_cancellation_point();