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-rw-r--r--pthreads/errno.c94
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diff --git a/pthreads/errno.c b/pthreads/errno.c
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+/*
+ * errno.c
+ *
+ * Description:
+ * This translation unit implements routines associated with spawning a new
+ * thread.
+ *
+ * --------------------------------------------------------------------------
+ *
+ * Pthreads-win32 - POSIX Threads Library for Win32
+ * Copyright(C) 1998 John E. Bossom
+ * Copyright(C) 1999,2005 Pthreads-win32 contributors
+ *
+ * Contact Email: rpj@callisto.canberra.edu.au
+ *
+ * The current list of contributors is contained
+ * in the file CONTRIBUTORS included with the source
+ * code distribution. The list can also be seen at the
+ * following World Wide Web location:
+ * http://sources.redhat.com/pthreads-win32/contributors.html
+ *
+ * This 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 of the License, or (at your option) any later version.
+ *
+ * This 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 this library in the file COPYING.LIB;
+ * if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#if defined(NEED_ERRNO)
+
+#include "pthread.h"
+#include "implement.h"
+
+static int reallyBad = ENOMEM;
+
+/*
+ * Re-entrant errno.
+ *
+ * Each thread has it's own errno variable in pthread_t.
+ *
+ * The benefit of using the pthread_t structure
+ * instead of another TSD key is TSD keys are limited
+ * on Win32 to 64 per process. Secondly, to implement
+ * it properly without using pthread_t you'd need
+ * to dynamically allocate an int on starting the thread
+ * and store it manually into TLS and then ensure that you free
+ * it on thread termination. We get all that for free
+ * by simply storing the errno on the pthread_t structure.
+ *
+ * MSVC and Mingw32 already have their own thread-safe errno.
+ *
+ * #if defined( _REENTRANT ) || defined( _MT )
+ * #define errno *_errno()
+ *
+ * int *_errno( void );
+ * #else
+ * extern int errno;
+ * #endif
+ *
+ */
+
+int *
+_errno (void)
+{
+ pthread_t self;
+ int *result;
+
+ if ((self = pthread_self ()) == NULL)
+ {
+ /*
+ * Yikes! unable to allocate a thread!
+ * Throw an exception? return an error?
+ */
+ result = &reallyBad;
+ }
+ else
+ {
+ result = &(self->ptErrno);
+ }
+
+ return (result);
+
+} /* _errno */
+
+#endif /* (NEED_ERRNO) */