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-rw-r--r--gl/lib/mbtowc-lock.h125
1 files changed, 125 insertions, 0 deletions
diff --git a/gl/lib/mbtowc-lock.h b/gl/lib/mbtowc-lock.h
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+++ b/gl/lib/mbtowc-lock.h
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+/* Use the internal lock used by mbrtowc and mbrtoc32.
+ Copyright (C) 2019-2022 Free Software Foundation, Inc.
+
+ This file 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.
+
+ This file 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 this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2019-2020. */
+
+/* Use a lock, so that no two threads can invoke mbtowc at the same time. */
+
+static inline int
+mbtowc_unlocked (wchar_t *pwc, const char *p, size_t m)
+{
+ /* Put the hidden internal state of mbtowc into its initial state.
+ This is needed at least with glibc, uClibc, and MSVC CRT.
+ See <https://sourceware.org/bugzilla/show_bug.cgi?id=9674>. */
+ mbtowc (NULL, NULL, 0);
+
+ return mbtowc (pwc, p, m);
+}
+
+/* Prohibit renaming this symbol. */
+#undef gl_get_mbtowc_lock
+
+#if GNULIB_MBRTOWC_SINGLE_THREAD
+
+/* All uses of this function are in a single thread. No locking needed. */
+
+static int
+mbtowc_with_lock (wchar_t *pwc, const char *p, size_t m)
+{
+ return mbtowc_unlocked (pwc, p, m);
+}
+
+#elif defined _WIN32 && !defined __CYGWIN__
+
+extern __declspec(dllimport) CRITICAL_SECTION *gl_get_mbtowc_lock (void);
+
+static int
+mbtowc_with_lock (wchar_t *pwc, const char *p, size_t m)
+{
+ CRITICAL_SECTION *lock = gl_get_mbtowc_lock ();
+ int ret;
+
+ EnterCriticalSection (lock);
+ ret = mbtowc_unlocked (pwc, p, m);
+ LeaveCriticalSection (lock);
+
+ return ret;
+}
+
+#elif HAVE_PTHREAD_API /* AIX, IRIX, Cygwin */
+
+extern
+# if defined _WIN32 || defined __CYGWIN__
+ __declspec(dllimport)
+# endif
+ pthread_mutex_t *gl_get_mbtowc_lock (void);
+
+# if HAVE_WEAK_SYMBOLS /* IRIX */
+
+ /* Avoid the need to link with '-lpthread'. */
+# pragma weak pthread_mutex_lock
+# pragma weak pthread_mutex_unlock
+
+ /* Determine whether libpthread is in use. */
+# pragma weak pthread_mutexattr_gettype
+ /* See the comments in lock.h. */
+# define pthread_in_use() \
+ (pthread_mutexattr_gettype != NULL || c11_threads_in_use ())
+
+# else
+# define pthread_in_use() 1
+# endif
+
+static int
+mbtowc_with_lock (wchar_t *pwc, const char *p, size_t m)
+{
+ if (pthread_in_use())
+ {
+ pthread_mutex_t *lock = gl_get_mbtowc_lock ();
+ int ret;
+
+ if (pthread_mutex_lock (lock))
+ abort ();
+ ret = mbtowc_unlocked (pwc, p, m);
+ if (pthread_mutex_unlock (lock))
+ abort ();
+
+ return ret;
+ }
+ else
+ return mbtowc_unlocked (pwc, p, m);
+}
+
+#elif HAVE_THREADS_H
+
+extern mtx_t *gl_get_mbtowc_lock (void);
+
+static int
+mbtowc_with_lock (wchar_t *pwc, const char *p, size_t m)
+{
+ mtx_t *lock = gl_get_mbtowc_lock ();
+ int ret;
+
+ if (mtx_lock (lock) != thrd_success)
+ abort ();
+ ret = mbtowc_unlocked (pwc, p, m);
+ if (mtx_unlock (lock) != thrd_success)
+ abort ();
+
+ return ret;
+}
+
+#endif