| The Android Open Source Project | dd7bc33 | 2009-03-03 19:32:55 -0800 | [diff] [blame] | 1 | /*- |
| 2 | * Copyright (c) 2003 Poul-Henning Kamp |
| 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 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| 15 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 16 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 17 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 18 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 19 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 20 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 21 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 22 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 23 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 24 | * SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | /* Functions to encode or decode struct dos_partition into a bytestream |
| 28 | * of correct endianess and packing. These functions do no validation |
| 29 | * or sanity checking, they only pack/unpack the fields correctly. |
| 30 | * |
| 31 | * NB! This file must be usable both in kernel and userland. |
| 32 | */ |
| 33 | |
| 34 | #include <sys/types.h> |
| 35 | #include <sys/endian.h> |
| 36 | |
| 37 | #include "diskmbr.h" |
| 38 | |
| 39 | static __inline uint32_t __unused |
| 40 | le32dec(const void *buf) |
| 41 | { |
| 42 | const uint8_t *p = (const uint8_t *)buf; |
| 43 | |
| 44 | return ((p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]); |
| 45 | } |
| 46 | |
| 47 | static __inline void |
| 48 | le32enc(void *pp, uint32_t u) |
| 49 | { |
| 50 | unsigned char *p = (unsigned char *)pp; |
| 51 | |
| 52 | p[0] = u & 0xff; |
| 53 | p[1] = (u >> 8) & 0xff; |
| 54 | p[2] = (u >> 16) & 0xff; |
| 55 | p[3] = (u >> 24) & 0xff; |
| 56 | } |
| 57 | |
| 58 | void |
| 59 | dos_partition_dec(void const *pp, struct dos_partition *d) |
| 60 | { |
| 61 | unsigned char const *p = pp; |
| 62 | |
| 63 | d->dp_flag = p[0]; |
| 64 | d->dp_shd = p[1]; |
| 65 | d->dp_ssect = p[2]; |
| 66 | d->dp_scyl = p[3]; |
| 67 | d->dp_typ = p[4]; |
| 68 | d->dp_ehd = p[5]; |
| 69 | d->dp_esect = p[6]; |
| 70 | d->dp_ecyl = p[7]; |
| 71 | d->dp_start = le32dec(p + 8); |
| 72 | d->dp_size = le32dec(p + 12); |
| 73 | } |
| 74 | |
| 75 | void |
| 76 | dos_partition_enc(void *pp, struct dos_partition *d) |
| 77 | { |
| 78 | unsigned char *p = pp; |
| 79 | |
| 80 | p[0] = d->dp_flag; |
| 81 | p[1] = d->dp_shd; |
| 82 | p[2] = d->dp_ssect; |
| 83 | p[3] = d->dp_scyl; |
| 84 | p[4] = d->dp_typ; |
| 85 | p[5] = d->dp_ehd; |
| 86 | p[6] = d->dp_esect; |
| 87 | p[7] = d->dp_ecyl; |
| 88 | le32enc(p + 8, d->dp_start); |
| 89 | le32enc(p + 12, d->dp_size); |
| 90 | } |