| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| #define HEAPSIZE (1024) |
| |
| static char __Heap[HEAPSIZE]; |
| |
| void * |
| _sbrk(int incr) |
| { |
| static char *brk = __Heap; |
| |
| void *prev_brk; |
| |
| if (incr < 0) { |
| /* Returning memory to the heap. */ |
| incr = -incr; |
| if (brk - incr < __Heap) { |
| prev_brk = (void *)-1; |
| } else { |
| prev_brk = brk; |
| brk -= incr; |
| } |
| } else { |
| /* Allocating memory from the heap. */ |
| if ((__Heap + HEAPSIZE) - brk >= incr) { |
| prev_brk = brk; |
| brk += incr; |
| } else { |
| prev_brk = (void *)-1; |
| } |
| } |
| |
| return prev_brk; |
| } |
