https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=472d0a228c56bd4783ebb0561667cda2de3cd168
commit 472d0a228c56bd4783ebb0561667cda2de3cd168 Author: John Hood <[email protected]> Date: Thu Feb 4 00:44:56 2016 -0500 Improve and simplify select(). * cygwait.h (cygwait_us) Remove; this reverts previous changes. * select.h: Eliminate redundant select_stuff::select_loop state. * select.cc (select): Eliminate redundant select_stuff::select_loop state. Eliminate redundant code for zero timeout. Do not return early on early timer return. (select_stuff::wait): Eliminate redundant select_stuff::select_loop state. Diff: --- winsup/cygwin/cygwait.h | 27 --------------------- winsup/cygwin/select.cc | 63 ++++++++++++------------------------------------- winsup/cygwin/select.h | 1 - 3 files changed, 15 insertions(+), 76 deletions(-) diff --git a/winsup/cygwin/cygwait.h b/winsup/cygwin/cygwait.h index 3e02cdd..1240f54 100644 --- a/winsup/cygwin/cygwait.h +++ b/winsup/cygwin/cygwait.h @@ -59,30 +59,3 @@ cygwait (DWORD howlong) { return cygwait (NULL, howlong); } - -extern inline DWORD __attribute__ ((always_inline)) -cygwait_us (HANDLE h, LONGLONG howlong, unsigned mask) -{ - LARGE_INTEGER li_howlong; - PLARGE_INTEGER pli_howlong; - if (howlong < 0LL) - pli_howlong = NULL; - else - { - li_howlong.QuadPart = -(10LL * howlong); - pli_howlong = &li_howlong; - } - return cygwait (h, pli_howlong, mask); -} - -static inline DWORD __attribute__ ((always_inline)) -cygwait_us (HANDLE h, LONGLONG howlong = -1) -{ - return cygwait_us (h, howlong, cw_cancel | cw_sig); -} - -static inline DWORD __attribute__ ((always_inline)) -cygwait_us (LONGLONG howlong) -{ - return cygwait_us (NULL, howlong); -} diff --git a/winsup/cygwin/select.cc b/winsup/cygwin/select.cc index 25b0c5a..556a79f 100644 --- a/winsup/cygwin/select.cc +++ b/winsup/cygwin/select.cc @@ -32,7 +32,6 @@ details. */ #include "pinfo.h" #include "sigproc.h" #include "cygtls.h" -#include "cygwait.h" /* * All these defines below should be in sys/types.h @@ -156,7 +155,7 @@ static int select (int maxfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, LONGLONG us) { - select_stuff::wait_states wait_state = select_stuff::select_loop; + select_stuff::wait_states wait_state = select_stuff::select_set_zero; int ret = 0; /* Record the current time for later use. */ @@ -182,30 +181,7 @@ select (int maxfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, } select_printf ("sel.always_ready %d", sel.always_ready); - /* Degenerate case. No fds to wait for. Just wait for time to run out - or signal to arrive. */ - if (sel.start.next == NULL) - switch (cygwait_us (us)) - { - case WAIT_SIGNALED: - select_printf ("signal received"); - /* select() is always interrupted by a signal so set EINTR, - unconditionally, ignoring any SA_RESTART detection by - call_signal_handler(). */ - _my_tls.call_signal_handler (); - set_sig_errno (EINTR); - wait_state = select_stuff::select_signalled; - break; - case WAIT_CANCELED: - sel.destroy (); - pthread::static_cancel_self (); - /*NOTREACHED*/ - default: - /* Set wait_state to zero below. */ - wait_state = select_stuff::select_set_zero; - break; - } - else if (sel.always_ready || us == 0) + if (sel.always_ready || us == 0) /* Catch any active fds via sel.poll() below */ wait_state = select_stuff::select_ok; else @@ -214,29 +190,24 @@ select (int maxfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, select_printf ("sel.wait returns %d", wait_state); - if (wait_state >= select_stuff::select_ok) + if (wait_state == select_stuff::select_ok) { UNIX_FD_ZERO (readfds, maxfds); UNIX_FD_ZERO (writefds, maxfds); UNIX_FD_ZERO (exceptfds, maxfds); - if (wait_state == select_stuff::select_set_zero) - ret = 0; - else - { - /* Set bit mask from sel records. This also sets ret to the - right value >= 0, matching the number of bits set in the - fds records. if ret is 0, continue to loop. */ - ret = sel.poll (readfds, writefds, exceptfds); - if (!ret) - wait_state = select_stuff::select_loop; - } + /* Set bit mask from sel records. This also sets ret to the + right value >= 0, matching the number of bits set in the + fds records. if ret is 0, continue to loop. */ + ret = sel.poll (readfds, writefds, exceptfds); + if (!ret) + wait_state = select_stuff::select_set_zero; } /* Always clean up everything here. If we're looping then build it all up again. */ sel.cleanup (); sel.destroy (); - /* Recalculate time remaining to wait if we are going to be looping. */ - if (wait_state == select_stuff::select_loop && us != -1) + /* Check and recalculate timeout. */ + if (us != -1LL && wait_state == select_stuff::select_set_zero) { select_printf ("recalculating us"); LONGLONG now = gtod.usecs (); @@ -258,7 +229,7 @@ select (int maxfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, } } } - while (wait_state == select_stuff::select_loop); + while (wait_state == select_stuff::select_set_zero); if (wait_state < select_stuff::select_ok) ret = -1; @@ -494,7 +465,7 @@ next_while:; to wait for. */ default: s = &start; - bool gotone = false; + res = select_set_zero; /* Some types of objects (e.g., consoles) wake up on "inappropriate" events like mouse movements. The verify function will detect these situations. If it returns false, then this wakeup was a false alarm @@ -508,13 +479,9 @@ next_while:; } else if ((((wait_ret >= m && s->windows_handle) || s->h == w4[wait_ret])) && s->verify (s, readfds, writefds, exceptfds)) - gotone = true; + res = select_ok; - if (!gotone) - res = select_loop; - else - res = select_ok; - select_printf ("gotone %d", gotone); + select_printf ("res after verify %d", res); break; } out: diff --git a/winsup/cygwin/select.h b/winsup/cygwin/select.h index 581ee4e..3c749ad 100644 --- a/winsup/cygwin/select.h +++ b/winsup/cygwin/select.h @@ -78,7 +78,6 @@ public: enum wait_states { select_signalled = -3, - select_loop = -2, select_error = -1, select_ok = 0, select_set_zero = 1
