From b3b1ddf6f8dca6fa12817c74298ed9c80e173c7c Mon Sep 17 00:00:00 2001 From: Tijl Coosemans Date: Fri, 26 Nov 2010 10:11:11 +0100 Subject: QKqueueFileSystemWatcherEngine: Use higher file descriptors. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit A file descriptor is used for every path to be monitored, but descriptors below FD_SETSIZE (typically 1024) are precious, for use with select(2). To allow the application (and other parts of Qt) to use select(2), try to duplicate the descriptor returned by open(2) above FD_SETSIZE and close(2) the original. However, only do so when the descriptor table is already fairly large (FD_SETSIZE / 2). This keeps the descriptor table small for applications that use only a few descriptors. While here, also set the close-on-exec flag on the (new) descriptor. Merge-request: 2425 Reviewed-by: João Abecasis --- src/corelib/io/qfilesystemwatcher_kqueue.cpp | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/corelib/io/qfilesystemwatcher_kqueue.cpp b/src/corelib/io/qfilesystemwatcher_kqueue.cpp index 29cd111..242c153 100644 --- a/src/corelib/io/qfilesystemwatcher_kqueue.cpp +++ b/src/corelib/io/qfilesystemwatcher_kqueue.cpp @@ -136,6 +136,14 @@ QStringList QKqueueFileSystemWatcherEngine::addPaths(const QStringList &paths, perror("QKqueueFileSystemWatcherEngine::addPaths: open"); continue; } + if (fd >= (int)FD_SETSIZE / 2 && fd < (int)FD_SETSIZE) { + int fddup = fcntl(fd, F_DUPFD, FD_SETSIZE); + if (fddup != -1) { + ::close(fd); + fd = fddup; + } + } + fcntl(fd, F_SETFD, FD_CLOEXEC); QT_STATBUF st; if (QT_FSTAT(fd, &st) == -1) { -- cgit v0.12