1 /* 2 * Copyright (C) 2015 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 <errno.h> 30 #include <sys/mman.h> 31 #include <stdarg.h> 32 #include <stdint.h> 33 #include <unistd.h> 34 35 #include "private/bionic_macros.h" 36 37 extern "C" void* ___mremap(void*, size_t, size_t, int, void*); 38 39 void* mremap(void* old_address, size_t old_size, size_t new_size, int flags, ...) { 40 // prevent allocations large enough for `end - start` to overflow 41 size_t rounded = __BIONIC_ALIGN(new_size, PAGE_SIZE); 42 if (rounded < new_size || rounded > PTRDIFF_MAX) { 43 errno = ENOMEM; 44 return MAP_FAILED; 45 } 46 47 void* new_address = nullptr; 48 // The optional argument is only valid if the MREMAP_FIXED flag is set, 49 // so we assume it's not present otherwise. 50 if ((flags & MREMAP_FIXED) != 0) { 51 va_list ap; 52 va_start(ap, flags); 53 new_address = va_arg(ap, void*); 54 va_end(ap); 55 } 56 return ___mremap(old_address, old_size, new_size, flags, new_address); 57 } 58
