diff options
author | normal <normal@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2018-05-18 08:01:07 +0000 |
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committer | normal <normal@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2018-05-18 08:01:07 +0000 |
commit | 74724107e96228c34f92a1f210342891bb29400e (patch) | |
tree | 1ed0c7b2e41d900eca421148ee888c6c87ad73c3 /thread.c | |
parent | c6da9cadb346cc1d250c7ed6d8fd33c62a11030e (diff) |
thread.c (rb_wait_for_single_fd): do not leak EINTR on timeout
We must not leak EINTR to users in case a signal hits a
ppoll/select caller right when (or just before) the timeout
expires. In other words, the timeout should take precedence
over the -1 result from ppoll or select.
We also try one more time in case of EINTR with a zero timeout,
since technically the syscall finished before timing out if
it returns EINTR.
Regression appeared in r62457
("thread.c (update_timespec): use timespec_update_expire",
commit e6bf0128add103730d8c96727f3ed4dab95088e4)
and is not in any stable release of Ruby.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63462 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'thread.c')
-rw-r--r-- | thread.c | 51 |
1 files changed, 33 insertions, 18 deletions
@@ -3783,28 +3783,38 @@ rb_fd_set(int fd, rb_fdset_t *set) #define rb_fd_no_init(fds) (void)(fds) #endif -static inline int -retryable(int e) +static int +wait_retryable(int *result, int errnum, struct timespec *timeout, + const struct timespec *end) { - if (e == EINTR) return TRUE; + if (*result < 0) { + switch (errnum) { + case EINTR: #ifdef ERESTART - if (e == ERESTART) return TRUE; + case ERESTART: #endif + *result = 0; + if (timeout && timespec_update_expire(timeout, end)) { + timeout->tv_sec = 0; + timeout->tv_nsec = 0; + } + return TRUE; + } + return FALSE; + } + else if (*result == 0) { + /* check for spurious wakeup */ + if (timeout) { + return !timespec_update_expire(timeout, end); + } + return TRUE; + } return FALSE; } #define restore_fdset(fds1, fds2) \ ((fds1) ? rb_fd_dup(fds1, fds2) : (void)0) -static inline int -update_timespec(struct timespec *timeout, const struct timespec *end) -{ - if (timeout) { - return !timespec_update_expire(timeout, end); - } - return TRUE; -} - static int do_select(int n, rb_fdset_t *const readfds, rb_fdset_t *const writefds, rb_fdset_t *const exceptfds, struct timeval *timeout) @@ -3827,7 +3837,7 @@ do_select(int n, rb_fdset_t *const readfds, rb_fdset_t *const writefds, (restore_fdset(readfds, &orig_read), \ restore_fdset(writefds, &orig_write), \ restore_fdset(exceptfds, &orig_except), \ - update_timespec(tsp, &end)) + TRUE) if (timeout) { getclockofday(&end); @@ -3852,13 +3862,16 @@ do_select(int n, rb_fdset_t *const readfds, rb_fdset_t *const writefds, }, ubf_select, th, FALSE); RUBY_VM_CHECK_INTS_BLOCKING(th->ec); - } while (result < 0 && retryable(errno = lerrno) && do_select_update()); + } while (wait_retryable(&result, lerrno, tsp, &end) && do_select_update()); #define fd_term(f) if (f##fds) rb_fd_term(&orig_##f) fd_term(read); fd_term(write); fd_term(except); #undef fd_term + if (result < 0) { + errno = lerrno; + } return result; } @@ -3992,9 +4005,11 @@ rb_wait_for_single_fd(int fd, int events, struct timeval *timeout) }, ubf_select, th, FALSE); RUBY_VM_CHECK_INTS_BLOCKING(th->ec); - } while (result < 0 && retryable(errno = lerrno) && - update_timespec(tsp, &end)); - if (result < 0) return -1; + } while (wait_retryable(&result, lerrno, tsp, &end)); + if (result < 0) { + errno = lerrno; + return -1; + } if (fds.revents & POLLNVAL) { errno = EBADF; |