From 2433d39b69743f100f972e7886f91a2e21795ef0 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Mon, 6 Jul 2020 16:06:51 -0300 Subject: [PATCH] linux: Add time64 select support The syscall __NR_pselect6_time64 (32-bit) or __NR_pselect6 (64-bit) is used as default. For architectures with __ASSUME_TIME64_SYSCALLS the 32-bit fallback uses __NR_select/__NR__newselect or __NR_pselect6 (it should cover the microblaze case where older kernels do not provide __NR_pselect6). Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15 kernel). Reviewed-by: Alistair Francis --- include/sys/select.h | 8 +++ include/time.h | 6 +++ sysdeps/unix/sysv/linux/select.c | 92 ++++++++++++++++++++++++-------- 3 files changed, 83 insertions(+), 23 deletions(-) diff --git a/include/sys/select.h b/include/sys/select.h index b5ae9af861..ec073deeba 100644 --- a/include/sys/select.h +++ b/include/sys/select.h @@ -5,8 +5,11 @@ /* Now define the internal interfaces. */ # if __TIMESIZE == 64 # define __pselect64 __pselect +# define __select64 __select #else # include +# include + extern int __pselect64 (int __nfds, fd_set *__readfds, fd_set *__writefds, fd_set *__exceptfds, const struct __timespec64 *__timeout, @@ -18,6 +21,11 @@ extern int __pselect32 (int __nfds, fd_set *__readfds, const struct __timespec64 *__timeout, const __sigset_t *__sigmask) attribute_hidden; + +extern int __select64 (int __nfds, fd_set *__readfds, + fd_set *__writefds, fd_set *__exceptfds, + struct __timeval64 *__timeout); +libc_hidden_proto (__select64) #endif extern int __pselect (int __nfds, fd_set *__readfds, fd_set *__writefds, fd_set *__exceptfds, diff --git a/include/time.h b/include/time.h index fe4da9ca10..936486e206 100644 --- a/include/time.h +++ b/include/time.h @@ -464,6 +464,12 @@ valid_timespec_to_timeval32 (const struct timespec ts) return (struct __timeval32) { (time_t) ts.tv_sec, ts.tv_nsec / 1000 }; } +static inline struct __timeval64 +valid_timespec_to_timeval64 (const struct timespec ts) +{ + return (struct __timeval64) { (time_t) ts.tv_sec, ts.tv_nsec / 1000 }; +} + /* Check if a value is in the valid nanoseconds range. Return true if it is, false otherwise. */ static inline bool diff --git a/sysdeps/unix/sysv/linux/select.c b/sysdeps/unix/sysv/linux/select.c index 54c50edba2..bed52fbda2 100644 --- a/sysdeps/unix/sysv/linux/select.c +++ b/sysdeps/unix/sysv/linux/select.c @@ -21,6 +21,7 @@ #include #include #include +#include /* Check the first NFDS descriptors each in READFDS (if not NULL) for read readiness, in WRITEFDS (if not NULL) for write readiness, and in EXCEPTFDS @@ -28,43 +29,88 @@ after waiting the interval specified therein. Returns the number of ready descriptors, or -1 for errors. */ -#ifdef __NR__newselect -# undef __NR_select -# define __NR_select __NR__newselect -#endif - int -__select (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, - struct timeval *timeout) +__select64 (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, + struct __timeval64 *timeout) { -#ifdef __NR_select - return SYSCALL_CANCEL (select, nfds, readfds, writefds, exceptfds, - timeout); -#else - int result; - struct timespec ts, *tsp = NULL; - - if (timeout) + struct __timespec64 ts64, *pts64 = NULL; + if (timeout != NULL) { - TIMEVAL_TO_TIMESPEC (timeout, &ts); - tsp = &ts; + ts64 = timeval64_to_timespec64 (*timeout); + pts64 = &ts64; } - result = SYSCALL_CANCEL (pselect6, nfds, readfds, writefds, exceptfds, tsp, - NULL); - - if (timeout) +#ifndef __NR_pselect6_time64 +# define __NR_pselect6_time64 __NR_pselect6 +#endif + int r; + if (supports_time64 ()) { + r = SYSCALL_CANCEL (pselect6_time64, nfds, readfds, writefds, exceptfds, + pts64, NULL); /* Linux by default will update the timeout after a pselect6 syscall (though the pselect() glibc call suppresses this behavior). Since select() on Linux has the same behavior as the pselect6 syscall, we update the timeout here. */ - TIMESPEC_TO_TIMEVAL (timeout, &ts); + if (r == 0 || errno != ENOSYS) + { + if (timeout != NULL) + TIMEVAL_TO_TIMESPEC (timeout, &ts64); + return r; + } + + mark_time64_unsupported (); } - return result; +#ifndef __ASSUME_TIME64_SYSCALLS + struct timespec ts32, *pts32 = NULL; + if (timeout != NULL) + { + if (! in_time_t_range (timeout->tv_sec)) + { + __set_errno (EINVAL); + return -1; + } + ts32 = valid_timespec64_to_timespec (ts64); + pts32 = &ts32; + } +# ifndef __ASSUME_PSELECT +# ifdef __NR__newselect +# undef __NR_select +# define __NR_select __NR__newselect +# endif + r = SYSCALL_CANCEL (select, nfds, readfds, writefds, exceptfds, pts32); +# else + r = SYSCALL_CANCEL (pselect6, nfds, readfds, writefds, exceptfds, pts32, + NULL); +# endif + if (r >= 0 && timeout != NULL) + *timeout = valid_timespec_to_timeval64 (ts32); #endif + + return r; } + +#if __TIMESIZE != 64 +libc_hidden_def (__select64) + +int +__select (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, + struct timeval *timeout) +{ + struct __timeval64 tv64, *ptv64 = NULL; + if (timeout != NULL) + { + tv64 = valid_timeval_to_timeval64 (*timeout); + ptv64 = &tv64; + } + int r = __select64 (nfds, readfds, writefds, exceptfds, ptv64); + if (r >= 0 && timeout != NULL) + /* The remanining timeout will be always less the input TIMEOUT. */ + *timeout = valid_timeval64_to_timeval (tv64); + return r; +} +#endif libc_hidden_def (__select) weak_alias (__select, select) -- 2.43.5