| Alexandre Lision | 7c6f4a6 | 2013-09-05 13:27:01 -0400 | [diff] [blame^] | 1 | /* |
| 2 | ** Copyright (C) 2005-2011 Erik de Castro Lopo |
| 3 | ** |
| 4 | ** This program is free software; you can redistribute it and/or modify |
| 5 | ** it under the terms of the GNU General Public License as published by |
| 6 | ** the Free Software Foundation; either version 2 of the License, or |
| 7 | ** (at your option) any later version. |
| 8 | ** |
| 9 | ** This program is distributed in the hope that it will be useful, |
| 10 | ** but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | ** GNU General Public License for more details. |
| 13 | ** |
| 14 | ** You should have received a copy of the GNU General Public License |
| 15 | ** along with this program; if not, write to the Free Software |
| 16 | ** Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 17 | */ |
| 18 | |
| 19 | /* |
| 20 | ** A simple checksum for short, int and float data. |
| 21 | */ |
| 22 | |
| 23 | #include "sfconfig.h" |
| 24 | |
| 25 | #include <stdio.h> |
| 26 | #include <stdlib.h> |
| 27 | #include <string.h> |
| 28 | #include <math.h> |
| 29 | |
| 30 | #include <sndfile.h> |
| 31 | |
| 32 | #include "regtest.h" |
| 33 | |
| 34 | #define BIG_PRIME 999983 |
| 35 | |
| 36 | #define ARRAY_LEN(x) ((int) (sizeof (x)) / (sizeof ((x) [0]))) |
| 37 | |
| 38 | static int short_checksum (SNDFILE * file, int start) ; |
| 39 | static int int_checksum (SNDFILE * file, int start) ; |
| 40 | static int float_checksum (SNDFILE * file, int start) ; |
| 41 | |
| 42 | int |
| 43 | calc_checksum (SNDFILE * file, const SF_INFO * info) |
| 44 | { int start ; |
| 45 | |
| 46 | /* Seed the checksum with data from the SF_INFO struct. */ |
| 47 | start = info->samplerate ; |
| 48 | start = start * BIG_PRIME + info->channels ; |
| 49 | start = start * BIG_PRIME + info->format ; |
| 50 | |
| 51 | switch (info->format & SF_FORMAT_SUBMASK) |
| 52 | { case SF_FORMAT_FLOAT : |
| 53 | case SF_FORMAT_DOUBLE : |
| 54 | return float_checksum (file, start) ; |
| 55 | |
| 56 | case SF_FORMAT_PCM_24 : |
| 57 | case SF_FORMAT_PCM_32 : |
| 58 | return int_checksum (file, start) ; |
| 59 | |
| 60 | default : |
| 61 | return short_checksum (file, start) ; |
| 62 | } ; |
| 63 | |
| 64 | return 0 ; |
| 65 | } /* calc_checksum */ |
| 66 | |
| 67 | /*------------------------------------------------------------------------------ |
| 68 | */ |
| 69 | |
| 70 | static union |
| 71 | { short s [1 << 16] ; |
| 72 | int i [1 << 15] ; |
| 73 | float f [1 << 15] ; |
| 74 | } data ; |
| 75 | |
| 76 | static int |
| 77 | short_checksum (SNDFILE * file, int start) |
| 78 | { int k, count ; |
| 79 | |
| 80 | do |
| 81 | { count = (int) sf_read_short (file, data.s, ARRAY_LEN (data.s)) ; |
| 82 | for (k = 0 ; k < count ; k++) |
| 83 | start = start * BIG_PRIME + data.s [k] ; |
| 84 | } |
| 85 | while (count > 0) ; |
| 86 | |
| 87 | return start ; |
| 88 | } /* short_checksum */ |
| 89 | |
| 90 | static int |
| 91 | int_checksum (SNDFILE * file, int start) |
| 92 | { int k, count ; |
| 93 | |
| 94 | do |
| 95 | { count = (int) sf_read_int (file, data.i, ARRAY_LEN (data.i)) ; |
| 96 | for (k = 0 ; k < count ; k++) |
| 97 | start = start * BIG_PRIME + data.i [k] ; |
| 98 | } |
| 99 | while (count > 0) ; |
| 100 | |
| 101 | return start ; |
| 102 | } /* int_checksum */ |
| 103 | |
| 104 | static int |
| 105 | float_checksum (SNDFILE * file, int start) |
| 106 | { int k, count ; |
| 107 | |
| 108 | do |
| 109 | { count = (int) sf_read_float (file, data.f, ARRAY_LEN (data.f)) ; |
| 110 | for (k = 0 ; k < count ; k++) |
| 111 | start = start * BIG_PRIME + lrintf (0x7FFFFFFF * data.f [k]) ; |
| 112 | } |
| 113 | while (count > 0) ; |
| 114 | |
| 115 | return start ; |
| 116 | } /* float_checksum */ |
| 117 | |