Mercurial > gnulib
view lib/mbsrtowcs-impl.h @ 37246:5cfb3a67238d
regex: avoid glibc deadlock during configure
glibc has a known bug where certain corruptions of the heap can
cause malloc to default to printing a debug message that includes
a backtrace, but the act of getting the backtrace uses dlopen
which in turn calls into malloc, causing a recursive lock ending
in deadlock. Thus, when configure is probing for a known glibc
heap corruption bug, the overall configure would hang.
The solution suggested by glibc developers is to force malloc
to quit printing debug messages, which avoids recursive malloc.
* m4/regex.m4 (gl_REGEX): Avoid recursive malloc deadlock when
glibc bug 15078 in turn triggers bug 16159.
Reported by Michal Privoznik.
Signed-off-by: Eric Blake <eblake@redhat.com>
author | Eric Blake <eblake@redhat.com> |
---|---|
date | Tue, 03 Dec 2013 10:34:13 -0700 |
parents | c741bc27922a |
children | 344018b6e5d7 |
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/* Convert string to wide string. Copyright (C) 2008-2013 Free Software Foundation, Inc. Written by Bruno Haible <bruno@clisp.org>, 2008. 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 3 of the License, 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 <http://www.gnu.org/licenses/>. */ size_t mbsrtowcs (wchar_t *dest, const char **srcp, size_t len, mbstate_t *ps) { if (ps == NULL) ps = &_gl_mbsrtowcs_state; { const char *src = *srcp; if (dest != NULL) { wchar_t *destptr = dest; for (; len > 0; destptr++, len--) { size_t src_avail; size_t ret; /* An optimized variant of src_avail = strnlen1 (src, MB_LEN_MAX); */ if (src[0] == '\0') src_avail = 1; else if (src[1] == '\0') src_avail = 2; else if (src[2] == '\0') src_avail = 3; else if (MB_LEN_MAX <= 4 || src[3] == '\0') src_avail = 4; else src_avail = 4 + strnlen1 (src + 4, MB_LEN_MAX - 4); /* Parse the next multibyte character. */ ret = mbrtowc (destptr, src, src_avail, ps); if (ret == (size_t)(-2)) /* Encountered a multibyte character that extends past a '\0' byte or that is longer than MB_LEN_MAX bytes. Cannot happen. */ abort (); if (ret == (size_t)(-1)) goto bad_input; if (ret == 0) { src = NULL; /* Here mbsinit (ps). */ break; } src += ret; } *srcp = src; return destptr - dest; } else { /* Ignore dest and len, don't store *srcp at the end, and don't clobber *ps. */ mbstate_t state = *ps; size_t totalcount = 0; for (;; totalcount++) { size_t src_avail; size_t ret; /* An optimized variant of src_avail = strnlen1 (src, MB_LEN_MAX); */ if (src[0] == '\0') src_avail = 1; else if (src[1] == '\0') src_avail = 2; else if (src[2] == '\0') src_avail = 3; else if (MB_LEN_MAX <= 4 || src[3] == '\0') src_avail = 4; else src_avail = 4 + strnlen1 (src + 4, MB_LEN_MAX - 4); /* Parse the next multibyte character. */ ret = mbrtowc (NULL, src, src_avail, &state); if (ret == (size_t)(-2)) /* Encountered a multibyte character that extends past a '\0' byte or that is longer than MB_LEN_MAX bytes. Cannot happen. */ abort (); if (ret == (size_t)(-1)) goto bad_input2; if (ret == 0) { /* Here mbsinit (&state). */ break; } src += ret; } return totalcount; } bad_input: *srcp = src; bad_input2: errno = EILSEQ; return (size_t)(-1); } }