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
calc_checksum(SNDFILE * file,const SF_INFO * info)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
short_checksum(SNDFILE * file,int start)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
int_checksum(SNDFILE * file,int start)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
float_checksum(SNDFILE * file,int start)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 (2147483648.0f * data.f [k]) ;
112 }
113 while (count > 0) ;
114
115 return start ;
116 } /* float_checksum */
117
118