From f7704bf77a926e53e8200528ab6abc1c9fdca511 Mon Sep 17 00:00:00 2001 From: Christian Franke Date: Mon, 15 Jan 2024 09:52:50 +0100 Subject: [PATCH] Cygwin: introduce close_range(2) This function closes or sets the close-on-exec flag for a specified range of file descriptors. It is available on FreeBSD and Linux. Signed-off-by: Christian Franke --- newlib/libc/include/sys/unistd.h | 9 ++++++ winsup/cygwin/cygwin.din | 1 + winsup/cygwin/include/cygwin/version.h | 3 +- winsup/cygwin/release/3.5.0 | 2 ++ winsup/cygwin/syscalls.cc | 43 ++++++++++++++++++++++++++ winsup/doc/new-features.xml | 4 +++ winsup/doc/posix.xml | 5 +++ 7 files changed, 66 insertions(+), 1 deletion(-) diff --git a/newlib/libc/include/sys/unistd.h b/newlib/libc/include/sys/unistd.h index 25532251c..0a31544ed 100644 --- a/newlib/libc/include/sys/unistd.h +++ b/newlib/libc/include/sys/unistd.h @@ -26,6 +26,15 @@ int chown (const char *__path, uid_t __owner, gid_t __group); int chroot (const char *__path); #endif int close (int __fildes); +#if defined(__CYGWIN__) && (__BSD_VISIBLE || __GNU_VISIBLE) +/* Available on FreeBSD (__BSD_VISIBLE) and Linux (__GNU_VISIBLE). */ +int close_range (unsigned int __firstfd, unsigned int __lastfd, int __flags); +#if __GNU_VISIBLE +/* Linux-specific, ignored by Cygwin. */ +#define CLOSE_RANGE_UNSHARE (1 << 1) +#endif +#define CLOSE_RANGE_CLOEXEC (1 << 2) +#endif #if __POSIX_VISIBLE >= 199209 size_t confstr (int __name, char *__buf, size_t __len); #endif diff --git a/winsup/cygwin/cygwin.din b/winsup/cygwin/cygwin.din index 9b76ce67a..9e354acc6 100644 --- a/winsup/cygwin/cygwin.din +++ b/winsup/cygwin/cygwin.din @@ -347,6 +347,7 @@ clog10l NOSIGFE clogf NOSIGFE clogl NOSIGFE close SIGFE +close_range SIGFE closedir SIGFE closelog SIGFE cnd_broadcast SIGFE diff --git a/winsup/cygwin/include/cygwin/version.h b/winsup/cygwin/include/cygwin/version.h index c8177c2b1..3036878c4 100644 --- a/winsup/cygwin/include/cygwin/version.h +++ b/winsup/cygwin/include/cygwin/version.h @@ -484,12 +484,13 @@ details. */ 347: Add c16rtomb, c32rtomb, mbrtoc16, mbrtoc32. 348: Add c8rtomb, mbrtoc. 349: Add fallocate. + 350: Add close_range. Note that we forgot to bump the api for ualarm, strtoll, strtoull, sigaltstack, sethostname. */ #define CYGWIN_VERSION_API_MAJOR 0 -#define CYGWIN_VERSION_API_MINOR 349 +#define CYGWIN_VERSION_API_MINOR 350 /* There is also a compatibity version number associated with the shared memory regions. It is incremented when incompatible changes are made to the shared diff --git a/winsup/cygwin/release/3.5.0 b/winsup/cygwin/release/3.5.0 index d0a6c2fc8..6209064a6 100644 --- a/winsup/cygwin/release/3.5.0 +++ b/winsup/cygwin/release/3.5.0 @@ -43,6 +43,8 @@ What's new: - New API calls: c8rtomb, c16rtomb, c32rtomb, mbrtoc8, mbrtoc16, mbrtoc32. +- New API call: close_range (available on FreeBSD and Linux). + - New API call: fallocate (Linux-specific). - Implement OSS-based sound mixer device (/dev/mixer). diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc index 486db1db6..2e1b56b7f 100644 --- a/winsup/cygwin/syscalls.cc +++ b/winsup/cygwin/syscalls.cc @@ -85,6 +85,49 @@ close_all_files (bool norelease) cygheap->fdtab.unlock (); } +/* Close or set the close-on-exec flag for all open file descriptors + from firstfd to lastfd. CLOSE_RANGE_UNSHARE is ignored. + Available on FreeBSD since 13 and Linux since 5.9 */ +extern "C" int +close_range (unsigned int firstfd, unsigned int lastfd, int flags) +{ + pthread_testcancel (); + + if (!(firstfd <= lastfd && + !(flags & ~(CLOSE_RANGE_UNSHARE | CLOSE_RANGE_CLOEXEC)))) + { + set_errno (EINVAL); + return -1; + } + + cygheap->fdtab.lock (); + + unsigned int size = (lastfd < cygheap->fdtab.size ? lastfd + 1 : + cygheap->fdtab.size); + + for (unsigned int i = firstfd; i < size; i++) + { + cygheap_fdget cfd ((int) i, false, false); + if (cfd < 0) + continue; + + if (flags & CLOSE_RANGE_CLOEXEC) + { + syscall_printf ("set FD_CLOEXEC on fd %u", i); + cfd->fcntl (F_SETFD, FD_CLOEXEC); + } + else + { + syscall_printf ("closing fd %u", i); + cfd->close_with_arch (); + cfd.release (); + } + } + + cygheap->fdtab.unlock (); + return 0; +} + extern "C" int dup (int fd) { diff --git a/winsup/doc/new-features.xml b/winsup/doc/new-features.xml index 6ae420031..0abe1c41c 100644 --- a/winsup/doc/new-features.xml +++ b/winsup/doc/new-features.xml @@ -74,6 +74,10 @@ posix_spawn_file_actions_addfchdir_np. New API calls: c8rtomb, c16rtomb, c32rtomb, mbrtoc8, mbrtoc16, mbrtoc32. + +New API call: close_range (available on FreeBSD and Linux). + + New API call: fallocate (Linux-specific). diff --git a/winsup/doc/posix.xml b/winsup/doc/posix.xml index 151aeb9fe..4ece761a8 100644 --- a/winsup/doc/posix.xml +++ b/winsup/doc/posix.xml @@ -1143,6 +1143,7 @@ also IEEE Std 1003.1-2017 (POSIX.1-2017). cfmakeraw cfsetspeed clearerr_unlocked + close_range daemon dn_comp dn_expand @@ -1297,6 +1298,7 @@ also IEEE Std 1003.1-2017 (POSIX.1-2017). clog10 clog10f clog10l + close_range (see chapter "Implementation Notes") crypt_r (available in external "crypt" library) dladdr (see chapter "Implementation Notes") dremf @@ -1655,6 +1657,9 @@ CLOCK_REALTIME and CLOCK_MONOTONIC. clock_setres, clock_settime, and timer_create currently support only CLOCK_REALTIME. +close_range ignores the Linux-specific flag +CLOSE_RANGE_UNSHARE. + POSIX file locks via fcntl or lockf, as well as BSD flock locks are advisory locks. They don't interact with Windows mandatory locks, nor -- 2.42.1