/* Array allocation from a fixed-size buffer.
Copyright (C) 2017-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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modify it under the terms of the GNU Lesser General Public
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__libc_alloc_buffer_alloc_array (struct alloc_buffer *buf, size_t element_size,
size_t align, size_t count)
size_t current = buf->__alloc_buffer_current;
/* The caller asserts that align is a power of two. */
size_t aligned = ALIGN_UP (current, align);
bool overflow = check_mul_overflow_size_t (element_size, count, &size);
size_t new_current = aligned + size;
if (!overflow /* Multiplication did not overflow. */
&& aligned >= current /* No overflow in align step. */
&& new_current >= size /* No overflow in size computation. */
&& new_current <= buf->__alloc_buffer_end) /* Room in buffer. */
buf->__alloc_buffer_current = new_current;
return (void *) aligned;