Mercurial > gnulib
view lib/sys-limits.h @ 39326:c82e97c04ab4
sys-limits.h: new file for crypto and safe I/O
* lib/af_alg.c: Include sys-limits.h.
(MAX_RW_COUNT): Remove. Use replaced by SYS_BUFSIZE_MAX.
(afalg_stream): Also reject negative sizes for sendfile; they
should not happen and the code is a bit cleaner and faster this way.
* lib/safe-read.c: Include sys-limits.h.
(BUGGY_READ_MAXIMUM): Remove. All uses replaced by SYS_BUFSIZE_MAX.
* lib/sys-limits.h: New file, with values and commentary derived
from the old safe-read.c and from GNU Emacs sysdep.c.
* modules/crypto/md5, modules/crypto/sha1, modules/crypto/sha256:
* modules/crypto/sha512, modules/safe-read, modules/safe-write:
Add lib/sys-limits.h to Files section.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Sat, 05 May 2018 10:27:38 -0700 |
parents | |
children | b06060465f09 |
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/* System call limits Copyright 2018 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, see <https://www.gnu.org/licenses/>. */ #ifndef _SYS_LIMITS_H #define _SYS_LIMITS_H #include <limits.h> /* Maximum number of bytes to read or write in a single system call. This can be useful for system calls like sendfile on GNU/Linux, which do not handle more than MAX_RW_COUNT bytes correctly. The Linux kernel MAX_RW_COUNT is at least INT_MAX >> 20 << 20, where the 20 comes from the Hexagon port with 1 MiB pages; use that as an approximation, as the exact value may not be available to us. Using this also works around a serious Linux bug before 2.6.16; see <https://bugzilla.redhat.com/show_bug.cgi?id=612839>. Using this also works around a Tru64 5.1 bug, where attempting to read INT_MAX bytes fails with errno == EINVAL. See <https://lists.gnu.org/r/bug-gnu-utils/2002-04/msg00010.html>. Using this is likely to work around similar bugs in other operating systems. */ enum { SYS_BUFSIZE_MAX = INT_MAX >> 20 << 20 }; #endif