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Comparing libev/ev.c (file contents):
Revision 1.438 by root, Tue May 29 21:03:44 2012 UTC vs.
Revision 1.448 by root, Tue Jul 24 16:28:08 2012 UTC

… …
559 559
560#define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */ 560#define ECB_C (__STDC__+0) /* this assumes that __STDC__ is either empty or a number */
561#define ECB_C99 (__STDC_VERSION__ >= 199901L) 561#define ECB_C99 (__STDC_VERSION__ >= 199901L)
562#define ECB_C11 (__STDC_VERSION__ >= 201112L) 562#define ECB_C11 (__STDC_VERSION__ >= 201112L)
563#define ECB_CPP (__cplusplus+0) 563#define ECB_CPP (__cplusplus+0)
564#define ECB_CPP98 (__cplusplus >= 199711L)
565#define ECB_CPP11 (__cplusplus >= 201103L) 564#define ECB_CPP11 (__cplusplus >= 201103L)
566 565
567/*****************************************************************************/ 566/*****************************************************************************/
568 567
569/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ 568/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
570/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ 569/* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
571 570
572#if ECB_NO_THREADS 571#if ECB_NO_THREADS
573# define ECB_NO_SMP 1 572 #define ECB_NO_SMP 1
574#endif 573#endif
575 574
576#if ECB_NO_SMP 575#if ECB_NO_SMP
577 #define ECB_MEMORY_FENCE do { } while (0) 576 #define ECB_MEMORY_FENCE do { } while (0)
578#endif 577#endif
… …
614 #endif 613 #endif
615#endif 614#endif
616 615
617#ifndef ECB_MEMORY_FENCE 616#ifndef ECB_MEMORY_FENCE
618 #if ECB_GCC_VERSION(4,7) 617 #if ECB_GCC_VERSION(4,7)
619 /* see comment below about the C11 memory model. in short - avoid */ 618 /* see comment below (stdatomic.h) about the C11 memory model. */
620 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST) 619 #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST)
621 #elif defined __clang && __has_feature (cxx_atomic) 620 #elif defined __clang && __has_feature (cxx_atomic)
622 /* see above */ 621 /* see comment below (stdatomic.h) about the C11 memory model. */
623 #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST) 622 #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST)
624 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__ 623 #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
625 #define ECB_MEMORY_FENCE __sync_synchronize () 624 #define ECB_MEMORY_FENCE __sync_synchronize ()
626 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
627 /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
628 #elif _MSC_VER >= 1400 /* VC++ 2005 */ 625 #elif _MSC_VER >= 1400 /* VC++ 2005 */
629 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) 626 #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
630 #define ECB_MEMORY_FENCE _ReadWriteBarrier () 627 #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
631 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ 628 #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
632 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () 629 #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
… …
646#ifndef ECB_MEMORY_FENCE 643#ifndef ECB_MEMORY_FENCE
647 #if ECB_C11 && !defined __STDC_NO_ATOMICS__ 644 #if ECB_C11 && !defined __STDC_NO_ATOMICS__
648 /* we assume that these memory fences work on all variables/all memory accesses, */ 645 /* we assume that these memory fences work on all variables/all memory accesses, */
649 /* not just C11 atomics and atomic accesses */ 646 /* not just C11 atomics and atomic accesses */
650 #include <stdatomic.h> 647 #include <stdatomic.h>
651 /* unfortunately, the C11 memory model seems to be very limited, and unable to express */ 648 /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */
652 /* simple barrier semantics. That means we need to take out thor's hammer. */ 649 /* any fence other than seq_cst, which isn't very efficient for us. */
650 /* Why that is, we don't know - either the C11 memory model is quite useless */
651 /* for most usages, or gcc and clang have a bug */
652 /* I *currently* lean towards the latter, and inefficiently implement */
653 /* all three of ecb's fences as a seq_cst fence */
653 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst) 654 #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst)
654 #endif
655 #endif 655 #endif
656#endif 656#endif
657 657
658#ifndef ECB_MEMORY_FENCE 658#ifndef ECB_MEMORY_FENCE
659 #if !ECB_AVOID_PTHREADS 659 #if !ECB_AVOID_PTHREADS
… …
1191} 1191}
1192 1192
1193static void * 1193static void *
1194ev_realloc_emul (void *ptr, long size) EV_THROW 1194ev_realloc_emul (void *ptr, long size) EV_THROW
1195{ 1195{
1196#if __GLIBC__
1197 return realloc (ptr, size);
1198#else
1199 /* some systems, notably openbsd and darwin, fail to properly 1196 /* some systems, notably openbsd and darwin, fail to properly
1200 * implement realloc (x, 0) (as required by both ansi c-89 and 1197 * implement realloc (x, 0) (as required by both ansi c-89 and
1201 * the single unix specification, so work around them here. 1198 * the single unix specification, so work around them here.
1199 * recently, also (at least) fedora and debian started breaking it,
1200 * despite documenting it otherwise.
1202 */ 1201 */
1203 1202
1204 if (size) 1203 if (size)
1205 return realloc (ptr, size); 1204 return realloc (ptr, size);
1206 1205
1207 free (ptr); 1206 free (ptr);
1208 return 0; 1207 return 0;
1209#endif
1210} 1208}
1211 1209
1212static void *(*alloc)(void *ptr, long size) EV_THROW = ev_realloc_emul; 1210static void *(*alloc)(void *ptr, long size) EV_THROW = ev_realloc_emul;
1213 1211
1214void ecb_cold 1212void ecb_cold
… …
1869static void noinline ecb_cold 1867static void noinline ecb_cold
1870evpipe_init (EV_P) 1868evpipe_init (EV_P)
1871{ 1869{
1872 if (!ev_is_active (&pipe_w)) 1870 if (!ev_is_active (&pipe_w))
1873 { 1871 {
1872 int fds [2];
1873
1874# if EV_USE_EVENTFD 1874# if EV_USE_EVENTFD
1875 fds [0] = -1;
1875 evfd = eventfd (0, EFD_NONBLOCK | EFD_CLOEXEC); 1876 fds [1] = eventfd (0, EFD_NONBLOCK | EFD_CLOEXEC);
1876 if (evfd < 0 && errno == EINVAL) 1877 if (fds [1] < 0 && errno == EINVAL)
1877 evfd = eventfd (0, 0); 1878 fds [1] = eventfd (0, 0);
1878 1879
1879 if (evfd >= 0) 1880 if (fds [1] < 0)
1880 {
1881 evpipe [0] = -1;
1882 fd_intern (evfd); /* doing it twice doesn't hurt */
1883 ev_io_set (&pipe_w, evfd, EV_READ);
1884 }
1885 else
1886# endif 1881# endif
1887 { 1882 {
1888 while (pipe (evpipe)) 1883 while (pipe (fds))
1889 ev_syserr ("(libev) error creating signal/async pipe"); 1884 ev_syserr ("(libev) error creating signal/async pipe");
1890 1885
1891 fd_intern (evpipe [0]); 1886 fd_intern (fds [0]);
1892 fd_intern (evpipe [1]);
1893 ev_io_set (&pipe_w, evpipe [0], EV_READ);
1894 } 1887 }
1895 1888
1889 fd_intern (fds [1]);
1890
1891 evpipe [0] = fds [0];
1892
1893 if (evpipe [1] < 0)
1894 evpipe [1] = fds [1]; /* first call, set write fd */
1895 else
1896 {
1897 /* on subsequent calls, do not change evpipe [1] */
1898 /* so that evpipe_write can always rely on its value. */
1899 /* this branch does not do anything sensible on windows, */
1900 /* so must not be executed on windows */
1901
1902 dup2 (fds [1], evpipe [1]);
1903 close (fds [1]);
1904 }
1905
1906 ev_io_set (&pipe_w, evpipe [0] < 0 ? evpipe [1] : evpipe [0], EV_READ);
1896 ev_io_start (EV_A_ &pipe_w); 1907 ev_io_start (EV_A_ &pipe_w);
1897 ev_unref (EV_A); /* watcher should not keep loop alive */ 1908 ev_unref (EV_A); /* watcher should not keep loop alive */
1898 } 1909 }
1899} 1910}
1900 1911
… …
1921 ECB_MEMORY_FENCE_RELEASE; 1932 ECB_MEMORY_FENCE_RELEASE;
1922 1933
1923 old_errno = errno; /* save errno because write will clobber it */ 1934 old_errno = errno; /* save errno because write will clobber it */
1924 1935
1925#if EV_USE_EVENTFD 1936#if EV_USE_EVENTFD
1926 if (evfd >= 0) 1937 if (evpipe [0] < 0)
1927 { 1938 {
1928 uint64_t counter = 1; 1939 uint64_t counter = 1;
1929 write (evfd, &counter, sizeof (uint64_t)); 1940 write (evpipe [1], &counter, sizeof (uint64_t));
1930 } 1941 }
1931 else 1942 else
1932#endif 1943#endif
1933 { 1944 {
1934#ifdef _WIN32 1945#ifdef _WIN32
… …
1954 int i; 1965 int i;
1955 1966
1956 if (revents & EV_READ) 1967 if (revents & EV_READ)
1957 { 1968 {
1958#if EV_USE_EVENTFD 1969#if EV_USE_EVENTFD
1959 if (evfd >= 0) 1970 if (evpipe [0] < 0)
1960 { 1971 {
1961 uint64_t counter; 1972 uint64_t counter;
1962 read (evfd, &counter, sizeof (uint64_t)); 1973 read (evpipe [1], &counter, sizeof (uint64_t));
1963 } 1974 }
1964 else 1975 else
1965#endif 1976#endif
1966 { 1977 {
1967 char dummy[4]; 1978 char dummy[4];
… …
2023 2034
2024 if (!EV_A) 2035 if (!EV_A)
2025 return; 2036 return;
2026#endif 2037#endif
2027 2038
2028 if (!ev_active (&pipe_w))
2029 return;
2030
2031 signals [signum - 1].pending = 1; 2039 signals [signum - 1].pending = 1;
2032 evpipe_write (EV_A_ &sig_pending); 2040 evpipe_write (EV_A_ &sig_pending);
2033} 2041}
2034 2042
2035static void 2043static void
… …
2045void noinline 2053void noinline
2046ev_feed_signal_event (EV_P_ int signum) EV_THROW 2054ev_feed_signal_event (EV_P_ int signum) EV_THROW
2047{ 2055{
2048 WL w; 2056 WL w;
2049 2057
2050 if (expect_false (signum <= 0 || signum > EV_NSIG)) 2058 if (expect_false (signum <= 0 || signum >= EV_NSIG))
2051 return; 2059 return;
2052 2060
2053 --signum; 2061 --signum;
2054 2062
2055#if EV_MULTIPLICITY 2063#if EV_MULTIPLICITY
… …
2353#if EV_ASYNC_ENABLE 2361#if EV_ASYNC_ENABLE
2354 async_pending = 0; 2362 async_pending = 0;
2355#endif 2363#endif
2356 pipe_write_skipped = 0; 2364 pipe_write_skipped = 0;
2357 pipe_write_wanted = 0; 2365 pipe_write_wanted = 0;
2366 evpipe [0] = -1;
2367 evpipe [1] = -1;
2358#if EV_USE_INOTIFY 2368#if EV_USE_INOTIFY
2359 fs_fd = flags & EVFLAG_NOINOTIFY ? -1 : -2; 2369 fs_fd = flags & EVFLAG_NOINOTIFY ? -1 : -2;
2360#endif 2370#endif
2361#if EV_USE_SIGNALFD 2371#if EV_USE_SIGNALFD
2362 sigfd = flags & EVFLAG_SIGNALFD ? -2 : -1; 2372 sigfd = flags & EVFLAG_SIGNALFD ? -2 : -1;
… …
2425 if (ev_is_active (&pipe_w)) 2435 if (ev_is_active (&pipe_w))
2426 { 2436 {
2427 /*ev_ref (EV_A);*/ 2437 /*ev_ref (EV_A);*/
2428 /*ev_io_stop (EV_A_ &pipe_w);*/ 2438 /*ev_io_stop (EV_A_ &pipe_w);*/
2429 2439
2430#if EV_USE_EVENTFD
2431 if (evfd >= 0)
2432 close (evfd);
2433#endif
2434
2435 if (evpipe [0] >= 0)
2436 {
2437 EV_WIN32_CLOSE_FD (evpipe [0]); 2440 if (evpipe [0] >= 0) EV_WIN32_CLOSE_FD (evpipe [0]);
2438 EV_WIN32_CLOSE_FD (evpipe [1]); 2441 if (evpipe [1] >= 0) EV_WIN32_CLOSE_FD (evpipe [1]);
2439 }
2440 } 2442 }
2441 2443
2442#if EV_USE_SIGNALFD 2444#if EV_USE_SIGNALFD
2443 if (ev_is_active (&sigfd_w)) 2445 if (ev_is_active (&sigfd_w))
2444 close (sigfd); 2446 close (sigfd);
… …
2530#endif 2532#endif
2531#if EV_USE_INOTIFY 2533#if EV_USE_INOTIFY
2532 infy_fork (EV_A); 2534 infy_fork (EV_A);
2533#endif 2535#endif
2534 2536
2537#if EV_SIGNAL_ENABLE || EV_ASYNC_ENABLE
2535 if (ev_is_active (&pipe_w)) 2538 if (ev_is_active (&pipe_w))
2536 { 2539 {
2537 /* pipe_write_wanted must be false now, so modifying fd vars should be safe */ 2540 /* pipe_write_wanted must be false now, so modifying fd vars should be safe */
2538 2541
2539 ev_ref (EV_A); 2542 ev_ref (EV_A);
2540 ev_io_stop (EV_A_ &pipe_w); 2543 ev_io_stop (EV_A_ &pipe_w);
2541 2544
2542#if EV_USE_EVENTFD
2543 if (evfd >= 0)
2544 close (evfd);
2545#endif
2546
2547 if (evpipe [0] >= 0) 2545 if (evpipe [0] >= 0)
2548 {
2549 EV_WIN32_CLOSE_FD (evpipe [0]); 2546 EV_WIN32_CLOSE_FD (evpipe [0]);
2550 EV_WIN32_CLOSE_FD (evpipe [1]);
2551 }
2552 2547
2553#if EV_SIGNAL_ENABLE || EV_ASYNC_ENABLE
2554 evpipe_init (EV_A); 2548 evpipe_init (EV_A);
2555 /* now iterate over everything, in case we missed something */ 2549 /* iterate over everything, in case we missed something before */
2556 pipecb (EV_A_ &pipe_w, EV_READ); 2550 ev_feed_event (EV_A_ &pipe_w, EV_CUSTOM);
2557#endif
2558 } 2551 }
2552#endif
2559 2553
2560 postfork = 0; 2554 postfork = 0;
2561} 2555}
2562 2556
2563#if EV_MULTIPLICITY 2557#if EV_MULTIPLICITY
… …
2736} 2730}
2737 2731
2738void 2732void
2739ev_loop_fork (EV_P) EV_THROW 2733ev_loop_fork (EV_P) EV_THROW
2740{ 2734{
2741 postfork = 1; /* must be in line with ev_default_fork */ 2735 postfork = 1;
2742} 2736}
2743 2737
2744/*****************************************************************************/ 2738/*****************************************************************************/
2745 2739
2746void 2740void
… …
2762} 2756}
2763 2757
2764void noinline 2758void noinline
2765ev_invoke_pending (EV_P) 2759ev_invoke_pending (EV_P)
2766{ 2760{
2767 for (pendingpri = NUMPRI; pendingpri--; ) /* pendingpri is modified during the loop */ 2761 pendingpri = NUMPRI;
2762
2763 while (pendingpri) /* pendingpri possibly gets modified in the inner loop */
2764 {
2765 --pendingpri;
2766
2768 while (pendingcnt [pendingpri]) 2767 while (pendingcnt [pendingpri])
2769 { 2768 {
2770 ANPENDING *p = pendings [pendingpri] + --pendingcnt [pendingpri]; 2769 ANPENDING *p = pendings [pendingpri] + --pendingcnt [pendingpri];
2771 2770
2772 p->w->pending = 0; 2771 p->w->pending = 0;
2773 EV_CB_INVOKE (p->w, p->events); 2772 EV_CB_INVOKE (p->w, p->events);
2774 EV_FREQUENT_CHECK; 2773 EV_FREQUENT_CHECK;
2775 } 2774 }
2775 }
2776} 2776}
2777 2777
2778#if EV_IDLE_ENABLE 2778#if EV_IDLE_ENABLE
2779/* make idle watchers pending. this handles the "call-idle */ 2779/* make idle watchers pending. this handles the "call-idle */
2780/* only when higher priorities are idle" logic */ 2780/* only when higher priorities are idle" logic */
… …
3138 backend_poll (EV_A_ waittime); 3138 backend_poll (EV_A_ waittime);
3139 assert ((loop_done = EVBREAK_CANCEL, 1)); /* assert for side effect */ 3139 assert ((loop_done = EVBREAK_CANCEL, 1)); /* assert for side effect */
3140 3140
3141 pipe_write_wanted = 0; /* just an optimisation, no fence needed */ 3141 pipe_write_wanted = 0; /* just an optimisation, no fence needed */
3142 3142
3143 ECB_MEMORY_FENCE_ACQUIRE;
3143 if (pipe_write_skipped) 3144 if (pipe_write_skipped)
3144 { 3145 {
3145 assert (("libev: pipe_w not active, but pipe not written", ev_is_active (&pipe_w))); 3146 assert (("libev: pipe_w not active, but pipe not written", ev_is_active (&pipe_w)));
3146 ev_feed_event (EV_A_ &pipe_w, EV_CUSTOM); 3147 ev_feed_event (EV_A_ &pipe_w, EV_CUSTOM);
3147 } 3148 }

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