From c3d3967cd2a9ebf8bd312ca5be09b6a844f3edf5 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Mon, 4 Mar 1996 22:45:04 +0000 Subject: Mon Mar 4 17:35:09 1996 Roland McGrath * hurd/catch-signal.c (hurd_safe_memmove): New function. (hurd_safe_copyin, hurd_safe_copyout): New functions. * hurd/hurd/sigpreempt.h: Declare them. --- hurd/catch-signal.c | 79 ++++++++++++++++++++++++++++++++++++++++++++ hurd/hurd/sigpreempt.h | 14 +++++++- sysdeps/unix/bsd/dirstream.h | 43 ------------------------ sysdeps/unix/bsd/readdir.c | 70 --------------------------------------- 4 files changed, 92 insertions(+), 114 deletions(-) delete mode 100644 sysdeps/unix/bsd/dirstream.h delete mode 100644 sysdeps/unix/bsd/readdir.c diff --git a/hurd/catch-signal.c b/hurd/catch-signal.c index 3e8ee6c7e2..c148193f71 100644 --- a/hurd/catch-signal.c +++ b/hurd/catch-signal.c @@ -85,3 +85,82 @@ hurd_safe_memset (void *dest, int byte, size_t nbytes) (vm_address_t) dest, (vm_address_t) dest + nbytes, &operate, SIG_ERR); } + + +error_t +hurd_safe_copyout (void *dest, const void *src, size_t nbytes) +{ + error_t operate (struct hurd_signal_preempter *preempter) + { + memcpy (dest, src, nbytes); + return 0; + } + return hurd_catch_signal (sigmask (SIGBUS) | sigmask (SIGSEGV), + (vm_address_t) dest, (vm_address_t) dest + nbytes, + &operate, SIG_ERR); +} + +error_t +hurd_safe_copyin (void *dest, const void *src, size_t nbytes) +{ + error_t operate (struct hurd_signal_preempter *preempter) + { + memcpy (dest, src, nbytes); + return 0; + } + return hurd_catch_signal (sigmask (SIGBUS) | sigmask (SIGSEGV), + (vm_address_t) src, (vm_address_t) src + nbytes, + &operate, SIG_ERR); +} + +error_t +hurd_safe_memmove (void *dest, const void *src, size_t nbytes) +{ + jmp_buf buf; + void throw (int signo, long int sigcode, struct sigcontext *scp) + { longjmp (buf, scp->sc_error ?: EGRATUITOUS); } + + struct hurd_signal_preempter src_preempter = + { + sigmask (SIGBUS) | sigmask (SIGSEGV), + (vm_address_t) src, (vm_address_t) src + nbytes, + NULL, (sighandler_t) &throw, + }; + struct hurd_signal_preempter dest_preempter = + { + sigmask (SIGBUS) | sigmask (SIGSEGV), + (vm_address_t) dest, (vm_address_t) dest + nbytes, + NULL, (sighandler_t) &throw, + &src_preempter + }; + + struct hurd_sigstate *const ss = _hurd_self_sigstate (); + error_t error; + + /* This returns again with nonzero value when we preempt a signal. */ + error = setjmp (buf); + + if (error == 0) + { + /* Install a signal preempter for the thread. */ + __spin_lock (&ss->lock); + src_preempter.next = ss->preempters; + ss->preempters = &dest_preempter; + __spin_unlock (&ss->lock); + + /* Do the copy; it might fault. */ + memmove (dest, src, nbytes); + } + + /* Either memmove completed happily and ERROR is still zero, or it hit + an expected signal and `throw' made setjmp return the signal error + code in ERROR. Now we can remove the preempter and return. */ + + __spin_lock (&ss->lock); + assert (ss->preempters == &dest_preempter); + ss->preempters = src_preempter.next; + __spin_unlock (&ss->lock); + + return error; +} + diff --git a/hurd/hurd/sigpreempt.h b/hurd/hurd/sigpreempt.h index eed67b2e94..4042ea2448 100644 --- a/hurd/hurd/sigpreempt.h +++ b/hurd/hurd/sigpreempt.h @@ -83,8 +83,20 @@ error_t hurd_catch_signal (sigset_t sigset, /* Convenience functions using `hurd_catch_signal'. */ -error_t hurd_safe_memmove (void *dest, const void *src, size_t nbytes); + +/* Like `memset', but catch faults in DEST. */ error_t hurd_safe_memset (void *dest, int byte, size_t nbytes); +/* Like `memcpy', but catch faults in SRC. */ +error_t hurd_safe_copyin (void *dest, const void *src, size_t nbytes); + +/* Like `memcpy', but catch faults in DEST. */ +error_t hurd_safe_copyout (void *dest, const void *src, size_t nbytes); + +/* Like `memmove', but catch faults in SRC or DEST. + If only one region is expected to fault, it is more efficient + to use `hurd_safe_copyin' or `hurd_safe_copyout' as appropriate. */ +error_t hurd_safe_memmove (void *dest, const void *src, size_t nbytes); + #endif /* hurd/sigpreempt.h */ diff --git a/sysdeps/unix/bsd/dirstream.h b/sysdeps/unix/bsd/dirstream.h deleted file mode 100644 index d46c59ec58..0000000000 --- a/sysdeps/unix/bsd/dirstream.h +++ /dev/null @@ -1,43 +0,0 @@ -/* Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc. -This file is part of the GNU C Library. - -The GNU C Library is free software; you can redistribute it and/or -modify it under the terms of the GNU Library General Public License as -published by the Free Software Foundation; either version 2 of the -License, or (at your option) any later version. - -The GNU C Library 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 -Library General Public License for more details. - -You should have received a copy of the GNU Library General Public -License along with the GNU C Library; see the file COPYING.LIB. If -not, write to the Free Software Foundation, Inc., 675 Mass Ave, -Cambridge, MA 02139, USA. */ - -#ifndef _DIRSTREAM_H - -#define _DIRSTREAM_H 1 - -#define __need_size_t -#include -#include /* For __off_t. */ - -/* Directory stream type. - - The BSD directory format is the same as `struct dirent', so `readdir' - returns a pointer into the buffer we read directory data into. */ - -struct __dirstream - { - int __fd; /* File descriptor. */ - - char *__data; /* Directory block. */ - size_t __allocation; /* Space allocated for the block. */ - size_t __offset; /* Current offset into the block. */ - size_t __size; /* Total valid data in the block. */ - __off_t __pos; /* Position in directory of this block. */ - }; - -#endif /* dirstream.h */ diff --git a/sysdeps/unix/bsd/readdir.c b/sysdeps/unix/bsd/readdir.c deleted file mode 100644 index e3d020cd46..0000000000 --- a/sysdeps/unix/bsd/readdir.c +++ /dev/null @@ -1,70 +0,0 @@ -/* Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. -This file is part of the GNU C Library. - -The GNU C Library is free software; you can redistribute it and/or -modify it under the terms of the GNU Library General Public License as -published by the Free Software Foundation; either version 2 of the -License, or (at your option) any later version. - -The GNU C Library 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 -Library General Public License for more details. - -You should have received a copy of the GNU Library General Public -License along with the GNU C Library; see the file COPYING.LIB. If -not, write to the Free Software Foundation, Inc., 675 Mass Ave, -Cambridge, MA 02139, USA. */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include "direct.h" -#include "dirstream.h" - -/* Read a directory entry from DIRP. */ -struct dirent * -DEFUN(readdir, (dirp), DIR *dirp) -{ - struct dirent *dp; - - if (dirp == NULL || dirp->__data == NULL) - { - errno = EINVAL; - return NULL; - } - - do - { - if (dirp->__offset >= dirp->__size) - { - /* We've emptied out our buffer. Refill it. */ - - ssize_t bytes = __getdirentries (dirp->__fd, dirp->__data, - dirp->__allocation, &dirp->__pos); - if (bytes <= 0) - return NULL; - dirp->__size = (size_t) bytes; - - /* Reset the offset into the buffer. */ - dirp->__offset = 0; - } - - dp = (struct dirent *) &dirp->__data[dirp->__offset]; - dirp->__offset += dp->d_reclen; - -#ifndef HAVE_D_TYPE - dp->d_namlen = ((struct direct *) dp)->d_namlen; - dp->d_type = DT_UNKNOWN; -#endif - - /* Loop to ignore deleted files. */ - } while (dp->d_fileno == 0); - - return dp; -} -- cgit 1.4.1