Diffstat (limited to 'core/multimedia/opieplayer/libmad/fixed.c') (more/less context) (show whitespace changes)
-rw-r--r-- | core/multimedia/opieplayer/libmad/fixed.c | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/core/multimedia/opieplayer/libmad/fixed.c b/core/multimedia/opieplayer/libmad/fixed.c index af1e87e..e71418a 100644 --- a/core/multimedia/opieplayer/libmad/fixed.c +++ b/core/multimedia/opieplayer/libmad/fixed.c @@ -1,5 +1,5 @@ /* * libmad - MPEG audio decoder library - * Copyright (C) 2000-2001 Robert Leslie + * Copyright (C) 2000-2004 Underbit Technologies, Inc. * * This program is free software; you can redistribute it and/or modify @@ -36,2 +36,46 @@ mad_fixed_t mad_f_abs(mad_fixed_t x) return x < 0 ? -x : x; } + +/* + * NAME: fixed->div() + * DESCRIPTION: perform division using fixed-point math + */ +mad_fixed_t mad_f_div(mad_fixed_t x, mad_fixed_t y) +{ + mad_fixed_t q, r; + unsigned int bits; + + q = mad_f_abs(x / y); + + if (x < 0) { + x = -x; + y = -y; + } + + r = x % y; + + if (y < 0) { + x = -x; + y = -y; + } + + if (q > mad_f_intpart(MAD_F_MAX) && + !(q == -mad_f_intpart(MAD_F_MIN) && r == 0 && (x < 0) != (y < 0))) + return 0; + + for (bits = MAD_F_FRACBITS; bits && r; --bits) { + q <<= 1, r <<= 1; + if (r >= y) + r -= y, ++q; + } + + /* round */ + if (2 * r >= y) + ++q; + + /* fix sign */ + if ((x < 0) != (y < 0)) + q = -q; + + return q << bits; +} |