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Diffstat (limited to 'sysdeps/generic/eloop-threshold.h')
-rw-r--r-- | sysdeps/generic/eloop-threshold.h | 72 |
1 files changed, 0 insertions, 72 deletions
diff --git a/sysdeps/generic/eloop-threshold.h b/sysdeps/generic/eloop-threshold.h deleted file mode 100644 index 0236368..0000000 --- a/sysdeps/generic/eloop-threshold.h +++ /dev/null @@ -1,72 +0,0 @@ -/* Threshold at which to diagnose ELOOP. Generic version. - Copyright (C) 2012-2025 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 Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <https://www.gnu.org/licenses/>. */ - -#ifndef _ELOOP_THRESHOLD_H -#define _ELOOP_THRESHOLD_H 1 - -#include <limits.h> -#include <sys/param.h> - -/* POSIX specifies SYMLOOP_MAX as the "Maximum number of symbolic - links that can be reliably traversed in the resolution of a - pathname in the absence of a loop." This makes it a minimum that - we should certainly accept. But it leaves open the possibility - that more might sometimes work--just not "reliably". - - For example, Linux implements a complex policy whereby there is a - small limit on the number of direct symlink traversals (a symlink - to a symlink to a symlink), but larger limit on the total number of - symlink traversals overall. Hence the SYMLOOP_MAX number should be - the small one, but the limit library functions enforce on users - should be the larger one. - - So, we use the larger of the reported SYMLOOP_MAX (if any) and our - own constant MIN_ELOOP_THRESHOLD, below. This constant should be - large enough that it never rules out a file name and directory tree - that the underlying system (i.e. calls to 'open' et al) would - resolve successfully. It should be small enough that actual loops - are detected without a huge number of iterations. */ - -#ifndef MIN_ELOOP_THRESHOLD -# define MIN_ELOOP_THRESHOLD 40 -#endif - -/* Return the maximum number of symlink traversals to permit - before diagnosing ELOOP. */ -static inline unsigned int __attribute__ ((const)) -__eloop_threshold (void) -{ -#ifdef SYMLOOP_MAX - const int symloop_max = SYMLOOP_MAX; -#else - /* The function is marked 'const' even though we use memory and - call a function, because sysconf is required to return the - same value in every call and so it must always be safe to - call __eloop_threshold exactly once and reuse the value. */ - static long int sysconf_symloop_max; - if (sysconf_symloop_max == 0) - sysconf_symloop_max = __sysconf (_SC_SYMLOOP_MAX); - const unsigned int symloop_max = (sysconf_symloop_max <= 0 - ? _POSIX_SYMLOOP_MAX - : sysconf_symloop_max); -#endif - - return MAX (symloop_max, MIN_ELOOP_THRESHOLD); -} - -#endif /* eloop-threshold.h */ |