diff options
| -rwxr-xr-x | configure | 58 | ||||
| -rw-r--r-- | src/eloop.c | 25 |
2 files changed, 25 insertions, 58 deletions
@@ -1221,61 +1221,9 @@ fi # Set this for eloop echo "#define HAVE_REALLOCARRAY" >>$CONFIG_H -if [ -z "$POLL" ]; then - printf "Testing for kqueue1 ... " - cat <<EOF >_kqueue1.c -#include <sys/event.h> -#include <sys/fcntl.h> -#include <sys/time.h> -int main(void) { - return kqueue1(O_CLOEXEC); -} -EOF - if $XCC _kqueue1.c -o _kqueue1 2>&3; then - POLL=kqueue1 - echo "yes" - else - echo "no" - fi - rm -f _kqueue1.c _kqueue1 -fi - -if [ -z "$POLL" ]; then - printf "Testing for kqueue ... " - cat <<EOF >_kqueue.c -#include <sys/types.h> -#include <sys/event.h> -#include <sys/time.h> -int main(void) { - return kqueue(); -} -EOF - if $XCC _kqueue.c -o _kqueue 2>&3; then - POLL=kqueue - echo "yes" - else - echo "no" - fi - rm -f _kqueue.c _kqueue -fi - -if [ -z "$POLL" ]; then - printf "Testing for epoll ... " - cat <<EOF >_epoll.c -#include <sys/epoll.h> -int main(void) { - return epoll_create1(EPOLL_CLOEXEC); -} -EOF - if $XCC _epoll.c -o _epoll 2>&3; then - POLL=epoll - echo "yes" - else - echo "no" - fi - rm -f _epoll.c _epoll -fi - +# Detect a polling mechanism. +# See src/eloop.c as to why we only detect ppoll, pollts and pselect and +# not others like epoll or kqueue. if [ -z "$POLL" ]; then printf "Testing for ppoll ... " cat <<EOF >_ppoll.c diff --git a/src/eloop.c b/src/eloop.c index a0581fc4..6785b316 100644 --- a/src/eloop.c +++ b/src/eloop.c @@ -26,6 +26,25 @@ * SUCH DAMAGE. */ +/* NOTES: + * Basically for a small number of fd's (total, not max fd) + * of say a few hundred, ppoll(2) performs just fine, if not faster than others. + * It also has the smallest memory and binary size footprint. + * ppoll(2) is available on all modern OS my software runs on. + * If ppoll is not available, then pselect(2) can be used instead. + * + * Both epoll(7) and kqueue(2) require an extra fd per process to manage + * their respective list of interest AND syscalls to manage it. + * So for a small number of fd's, these are more resource intensive, + * especially when used with more than one process. + * + * epoll avoids the resource limit RLIMIT_NOFILE Linux poll stupidly applies. + * kqueue avoids the same limit on OpenBSD. + * ppoll can still be secured in both by using SEECOMP or pledge. + * + * Taking this all into account, ppoll(2) is the default mechanism used here. + */ + #if (defined(__unix__) || defined(unix)) && !defined(USG) #include <sys/param.h> #endif @@ -51,10 +70,10 @@ #if defined(HAVE_KQUEUE) || defined(HAVE_EPOLL) || defined(HAVE_PPOLL) #elif defined(HAVE_POLLTS) #define ppoll pollts -#elif !defined(HAVE_PSELECT) -#pragma message("Compiling eloop with pselect(2) support.") -#define HAVE_PSELECT +#elif defined(HAVE_PSELECT) #define ppoll eloop_ppoll +#else +#define HAVE_PPOLL #endif #if defined(HAVE_KQUEUE) |