diff options
Diffstat (limited to 'gnulib-tests/pselect.c')
-rw-r--r-- | gnulib-tests/pselect.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/gnulib-tests/pselect.c b/gnulib-tests/pselect.c new file mode 100644 index 0000000..1b8c191 --- /dev/null +++ b/gnulib-tests/pselect.c @@ -0,0 +1,118 @@ +/* pselect - synchronous I/O multiplexing + + Copyright 2011-2023 Free Software Foundation, Inc. + + This file is part of gnulib. + + This file is free software: you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + This file is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* written by Paul Eggert */ + +#include <config.h> + +#include <sys/select.h> + +#include <errno.h> +#include <signal.h> + +/* Examine the size-NFDS file descriptor sets in RFDS, WFDS, and XFDS + to see whether some of their descriptors are ready for reading, + ready for writing, or have exceptions pending. Wait for at most + TIMEOUT seconds, and use signal mask SIGMASK while waiting. A null + pointer parameter stands for no descriptors, an infinite timeout, + or an unaffected signal mask. */ + +#if !HAVE_PSELECT + +int +pselect (int nfds, fd_set *restrict rfds, + fd_set *restrict wfds, fd_set *restrict xfds, + struct timespec const *restrict timeout, + sigset_t const *restrict sigmask) +{ + int select_result; + sigset_t origmask; + struct timeval tv, *tvp; + + if (nfds < 0 || nfds > FD_SETSIZE) + { + errno = EINVAL; + return -1; + } + + if (timeout) + { + if (! (0 <= timeout->tv_nsec && timeout->tv_nsec < 1000000000)) + { + errno = EINVAL; + return -1; + } + + tv = (struct timeval) { + .tv_sec = timeout->tv_sec, + .tv_usec = (timeout->tv_nsec + 999) / 1000 + }; + tvp = &tv; + } + else + tvp = NULL; + + /* Signal mask munging should be atomic, but this is the best we can + do in this emulation. */ + if (sigmask) + pthread_sigmask (SIG_SETMASK, sigmask, &origmask); + + select_result = select (nfds, rfds, wfds, xfds, tvp); + + if (sigmask) + { + int select_errno = errno; + pthread_sigmask (SIG_SETMASK, &origmask, NULL); + errno = select_errno; + } + + return select_result; +} + +#else /* HAVE_PSELECT */ +# include <unistd.h> +# undef pselect + +int +rpl_pselect (int nfds, fd_set *restrict rfds, + fd_set *restrict wfds, fd_set *restrict xfds, + struct timespec const *restrict timeout, + sigset_t const *restrict sigmask) +{ + int i; + + /* FreeBSD 8.2 has a bug: it does not always detect invalid fds. */ + if (nfds < 0 || nfds > FD_SETSIZE) + { + errno = EINVAL; + return -1; + } + for (i = 0; i < nfds; i++) + { + if (((rfds && FD_ISSET (i, rfds)) + || (wfds && FD_ISSET (i, wfds)) + || (xfds && FD_ISSET (i, xfds))) + && dup2 (i, i) != i) + return -1; + } + + return pselect (nfds, rfds, wfds, xfds, timeout, sigmask); +} + +#endif |