diff options
Diffstat (limited to 'cpukit/libcsupport/src/rtems_heap_sbrk_greedy.c')
-rw-r--r-- | cpukit/libcsupport/src/rtems_heap_sbrk_greedy.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/cpukit/libcsupport/src/rtems_heap_sbrk_greedy.c b/cpukit/libcsupport/src/rtems_heap_sbrk_greedy.c new file mode 100644 index 0000000000..49ae2a7c87 --- /dev/null +++ b/cpukit/libcsupport/src/rtems_heap_sbrk_greedy.c @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ + +/** + * @file + * + * @brief Greedy Allocate that Empties the sbrk system call + * + * @ingroup MallocSupport + * + * @brief Greedy allocation os sbrk system call memory + * + * The call consumes all the avialable sbrk memory extending + * the supplied heap with it. There is no free as sbrk memory + * is only ever allocated. + */ + +/* + * Copyright (c) 2021 Chris Johns. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "malloc_p.h" + +void rtems_heap_sbrk_greedy_allocate( + Heap_Control *heap, + size_t alloc_size +) +{ + while ( alloc_size > 0 ) { + void *p = (*rtems_malloc_extend_handler)( heap, alloc_size ); + if ( p == NULL ) { + alloc_size >>= 1; + } else { + if ( rtems_malloc_dirty_helper != NULL ) { + (*rtems_malloc_dirty_helper)( p, alloc_size ); + } + } + } +} |