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Diffstat (limited to 'sysdeps/generic/min-eloop-threshold.h')
-rw-r--r-- | sysdeps/generic/min-eloop-threshold.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/sysdeps/generic/min-eloop-threshold.h b/sysdeps/generic/min-eloop-threshold.h new file mode 100644 index 0000000..2ac12ed --- /dev/null +++ b/sysdeps/generic/min-eloop-threshold.h @@ -0,0 +1,42 @@ +/* Minimum 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 _MIN_ELOOP_THRESHOLD_H +#define _MIN_ELOOP_THRESHOLD_H 1 + +/* 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. + + 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. */ + +#define MIN_ELOOP_THRESHOLD 40 + +#endif |