diff options
Diffstat (limited to 'lib/poll.c')
| -rw-r--r-- | lib/poll.c | 83 |
1 files changed, 50 insertions, 33 deletions
diff --git a/lib/poll.c b/lib/poll.c index e70e8b354..7b1e58266 100644 --- a/lib/poll.c +++ b/lib/poll.c @@ -1,7 +1,7 @@ /* Emulation for poll(2) Contributed by Paolo Bonzini. - Copyright 2001-2003, 2006-2015 Free Software Foundation, Inc. + Copyright 2001-2003, 2006-2014 Free Software Foundation, Inc. This file is part of gnulib. @@ -33,6 +33,7 @@ #include <errno.h> #include <limits.h> +#include <assert.h> #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ # define WINDOWS_NATIVE @@ -44,12 +45,11 @@ # include "msvc-nothrow.h" #else # include <sys/time.h> +# include <sys/socket.h> +# include <sys/select.h> # include <unistd.h> #endif -#include <sys/select.h> -#include <sys/socket.h> - #ifdef HAVE_SYS_IOCTL_H # include <sys/ioctl.h> #endif @@ -59,8 +59,6 @@ #include <time.h> -#include "assure.h" - #ifndef INFTIM # define INFTIM (-1) #endif @@ -72,11 +70,9 @@ #ifdef WINDOWS_NATIVE -static BOOL IsConsoleHandle (HANDLE h) -{ - DWORD mode; - return GetConsoleMode (h, &mode) != 0; -} +/* Optimized test whether a HANDLE refers to a console. + See <http://lists.gnu.org/archive/html/bug-gnulib/2009-08/msg00065.html>. */ +#define IsConsoleHandle(h) (((intptr_t) (h) & 3) == 3) static BOOL IsSocketHandle (HANDLE h) @@ -335,15 +331,26 @@ poll (struct pollfd *pfd, nfds_t nfd, int timeout) int maxfd, rc; nfds_t i; - if (nfd < 0) +# ifdef _SC_OPEN_MAX + static int sc_open_max = -1; + + if (nfd < 0 + || (nfd > sc_open_max + && (sc_open_max != -1 + || nfd > (sc_open_max = sysconf (_SC_OPEN_MAX))))) { errno = EINVAL; return -1; } - /* Don't check directly for NFD too large. Any practical use of a - too-large NFD is caught by one of the other checks below, and - checking directly for getdtablesize is too much of a portability - and/or performance and/or correctness hassle. */ +# else /* !_SC_OPEN_MAX */ +# ifdef OPEN_MAX + if (nfd < 0 || nfd > OPEN_MAX) + { + errno = EINVAL; + return -1; + } +# endif /* OPEN_MAX -- else, no check is needed */ +# endif /* !_SC_OPEN_MAX */ /* EFAULT is not necessary to implement, but let's do it in the simplest case. */ @@ -384,17 +391,10 @@ poll (struct pollfd *pfd, nfds_t nfd, int timeout) { if (pfd[i].fd < 0) continue; - if (maxfd < pfd[i].fd) - { - maxfd = pfd[i].fd; - if (FD_SETSIZE <= maxfd) - { - errno = EINVAL; - return -1; - } - } + if (pfd[i].events & (POLLIN | POLLRDNORM)) FD_SET (pfd[i].fd, &rfds); + /* see select(2): "the only exceptional condition detectable is out-of-band data received on a socket", hence we push POLLWRBAND events onto wfds instead of efds. */ @@ -402,6 +402,18 @@ poll (struct pollfd *pfd, nfds_t nfd, int timeout) FD_SET (pfd[i].fd, &wfds); if (pfd[i].events & (POLLPRI | POLLRDBAND)) FD_SET (pfd[i].fd, &efds); + if (pfd[i].fd >= maxfd + && (pfd[i].events & (POLLIN | POLLOUT | POLLPRI + | POLLRDNORM | POLLRDBAND + | POLLWRNORM | POLLWRBAND))) + { + maxfd = pfd[i].fd; + if (maxfd > FD_SETSIZE) + { + errno = EOVERFLOW; + return -1; + } + } } /* examine fd sets */ @@ -412,13 +424,18 @@ poll (struct pollfd *pfd, nfds_t nfd, int timeout) /* establish results */ rc = 0; for (i = 0; i < nfd; i++) - { - pfd[i].revents = (pfd[i].fd < 0 - ? 0 - : compute_revents (pfd[i].fd, pfd[i].events, - &rfds, &wfds, &efds)); - rc += pfd[i].revents != 0; - } + if (pfd[i].fd < 0) + pfd[i].revents = 0; + else + { + int happened = compute_revents (pfd[i].fd, pfd[i].events, + &rfds, &wfds, &efds); + if (happened) + { + pfd[i].revents = happened; + rc++; + } + } return rc; #else @@ -461,7 +478,7 @@ restart: continue; h = (HANDLE) _get_osfhandle (pfd[i].fd); - assure (h != NULL); + assert (h != NULL); if (IsSocketHandle (h)) { int requested = FD_CLOSE; |