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Diffstat (limited to 'gnuradio-core/src/lib/missing/posix_memalign.cc')
-rw-r--r--gnuradio-core/src/lib/missing/posix_memalign.cc114
1 files changed, 114 insertions, 0 deletions
diff --git a/gnuradio-core/src/lib/missing/posix_memalign.cc b/gnuradio-core/src/lib/missing/posix_memalign.cc
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index 000000000..aaeff7804
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+++ b/gnuradio-core/src/lib/missing/posix_memalign.cc
@@ -0,0 +1,114 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2008,2009 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio 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, or (at your option)
+ * any later version.
+ *
+ * GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "posix_memalign.h"
+
+#ifdef HAVE_MALLOC_H
+// for Cygwin valloc () prototype
+#include <malloc.h>
+#endif
+
+#ifndef HAVE_POSIX_MEMALIGN
+
+/* emulate posix_memalign functionality, to some degree */
+
+#include <errno.h>
+#include "gr_pagesize.h"
+
+int posix_memalign
+(void **memptr, size_t alignment, size_t size)
+{
+ /* emulate posix_memalign functionality, to some degree */
+
+ /* make sure the return handle is valid; return "bad address" if not valid */
+ if (memptr == 0)
+ return (EFAULT);
+ *memptr = (void*) 0;
+
+ /* make sure 'alignment' is a power of 2
+ * and multiple of sizeof (void*)
+ */
+
+ /* make sure 'alignment' is a multiple of sizeof (void*) */
+ if ((alignment % sizeof (void*)) != 0)
+ return (EINVAL);
+
+ /* make sure 'alignment' is a power of 2 */
+ if ((alignment & (alignment - 1)) != 0)
+ return (EINVAL);
+
+ /* good alignment */
+
+#if (ALIGNED_MALLOC != 0)
+
+ /* if 'malloc' is known to be aligned, and the desired 'alignment'
+ * matches is <= that provided by 'malloc', then use 'malloc'. This
+ * works on, e.g., Darwin 8 & 9: for which malloc is 16-byte aligned.
+ */
+ size_t am = (size_t) ALIGNED_MALLOC;
+ if (alignment <= am) {
+ /* make sure ALIGNED_MALLOC is a power of 2, to guarantee that the
+ * alignment is correct (since 'alignment' must be a power of 2).
+ */
+ if ((am & (am - 1)) != 0)
+ return (EINVAL);
+ /* good malloc alignment */
+ *memptr = malloc (size);
+ }
+
+#endif /* (ALIGNED_MALLOC != 0) */
+#ifdef HAVE_VALLOC
+
+ if (*memptr == (void*) 0) {
+ /* try valloc if it exists */
+ /* cheap and easy way to make sure alignment is met, so long as it
+ * is <= pagesize () */
+ if (alignment <= (size_t) gr_pagesize ()) {
+ *memptr = valloc (size);
+ }
+ }
+
+#endif /* HAVE_VALLOC */
+
+#if (ALIGNED_MALLOC == 0) && !defined (HAVE_VALLOC)
+ /* no posix_memalign, valloc, and malloc isn't known to be aligned
+ * (enough for the input arguments); no idea what to do.
+ */
+
+#error gnuradio-core/src/libmissing/posix_memalign.cc: Cannot find a way to alloc aligned memory.
+
+#endif
+
+ /* if the pointer wasn't allocated properly, return that there was
+ * not enough memory to allocate; otherwise, return OK (0).
+ */
+ if (*memptr == (void*) 0)
+ return (ENOMEM);
+ else
+ return (0);
+};
+
+#endif /* ! HAVE_POSIX_MEMALIGN */