From 1dfec8a97094a26317eac9b3d8a1c16eb1a7dbea Mon Sep 17 00:00:00 2001 From: =?utf8?q?Carlo=20Marcelo=20Arenas=20Bel=C3=B3n?= Date: Sat, 19 Aug 2017 16:01:46 -0700 Subject: [PATCH] configure: avoid false positive in DragonFlyBSD by default, the max buffer size is 16K and histeresis is at 50%, so a bigger read is needed to unlock writes than you would expect from other BSD (512 bytes) this doesn't introduce any regression on FreeBSD 11.1, OpenBSD 6.1, NetBSD 7.1, macOS 10.12.6 and of course DragonFlyBSD 4.8.1, and most of them show a max pipe size of 64K, so the read call should drain them all regardless of how conservative they are on the free pipe space they will require (usually 512 bytes) before kevent reports the fd as ready for write. I couldn't find a reference to which bug this code was trying to look for and it seems to be there from the beginning of git history so it might be no longer relevant. Issue: #548 --- cmake/CheckWorkingKqueue.cmake | 6 +++--- configure.ac | 8 +++++++- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/cmake/CheckWorkingKqueue.cmake b/cmake/CheckWorkingKqueue.cmake index 47bf4e83..f22f011b 100644 --- a/cmake/CheckWorkingKqueue.cmake +++ b/cmake/CheckWorkingKqueue.cmake @@ -17,7 +17,7 @@ main(int argc, char **argv) int fd[2]; struct kevent ev; struct timespec ts; - char buf[8000]; + char buf[80000]; if (pipe(fd) == -1) exit(1); @@ -27,7 +27,7 @@ main(int argc, char **argv) while ((n = write(fd[1], buf, sizeof(buf))) == sizeof(buf)) ; - if ((kq = kqueue()) == -1) + if ((kq = kqueue()) == -1) exit(1); memset(&ev, 0, sizeof(ev)); @@ -49,4 +49,4 @@ main(int argc, char **argv) exit(0); } -" EVENT__HAVE_WORKING_KQUEUE) \ No newline at end of file +" EVENT__HAVE_WORKING_KQUEUE) diff --git a/configure.ac b/configure.ac index 696c8cd6..e5088ac5 100644 --- a/configure.ac +++ b/configure.ac @@ -517,6 +517,12 @@ if test "x$ac_cv_header_sys_event_h" = "xyes"; then if test "x$havekqueue" = "xyes" ; then AC_MSG_CHECKING(for working kqueue) AC_TRY_RUN( +#ifdef HAVE_STDLIB_H +#include +#endif +#ifdef HAVE_STRING_H +#include +#endif #include #include #include @@ -532,7 +538,7 @@ main(int argc, char **argv) int fd[[2]]; struct kevent ev; struct timespec ts; - char buf[[8000]]; + char buf[[80000]]; if (pipe(fd) == -1) exit(1); -- 2.40.0