1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <unistd.h> 30 #include <errno.h> 31 32 /* Shared with brk.c. */ 33 extern "C" { 34 void* __bionic_brk; // TODO: should be __LIBC_HIDDEN__ but accidentally exported by NDK :-( 35 } 36 37 void* sbrk(ptrdiff_t increment) { 38 if (__bionic_brk == NULL) { 39 __bionic_brk = __brk(NULL); 40 } 41 42 void* original_brk = __bionic_brk; 43 void* desired_brk = (void*) ((uintptr_t) original_brk + increment); 44 45 void* new_brk = __brk(desired_brk); 46 if (new_brk == (void*) -1) { 47 return new_brk; 48 } else if (new_brk < desired_brk) { 49 errno = ENOMEM; 50 return (void*) -1; 51 } 52 53 __bionic_brk = new_brk; 54 return original_brk; 55 } 56
