www.pudn.com > shine.zip > portableio.c
// Shine is an MP3 encoder // Copyright (C) 1999-2000 Gabriel Bouvigne // // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Library General Public // License as published by the Free Software Foundation; either // version 2 of the License, or (at your option) any later version. // // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // Library General Public License for more details. /* Copyright (C) 1988-1991 Apple Computer, Inc. * All Rights Reserved. * * Warranty Information * Even though Apple has reviewed this software, Apple makes no warranty * or representation, either express or implied, with respect to this * software, its quality, accuracy, merchantability, or fitness for a * particular purpose. As a result, this software is provided "as is," * and you, its user, are assuming the entire risk as to its quality * and accuracy. * * This code may be used and freely distributed as long as it includes * this copyright notice and the warranty information. * * * Motorola processors (Macintosh, Sun, Sparc, MIPS, etc) * pack bytes from high to low (they are big-endian). * Use the HighLow routines to match the native format * of these machines. * * Intel-like machines (PCs, Sequent) * pack bytes from low to high (the are little-endian). * Use the LowHigh routines to match the native format * of these machines. * * These routines have been tested on the following machines: * Apple Macintosh, MPW 3.1 C compiler * Apple Macintosh, THINK C compiler * Silicon Graphics IRIS, MIPS compiler * Cray X/MP and Y/MP * Digital Equipment VAX * * * Implemented by Malcolm Slaney and Ken Turkowski. * * Malcolm Slaney contributions during 1988-1990 include big- and little- * endian file I/O, conversion to and from Motorola's extended 80-bit * floating-point format, and conversions to and from IEEE single- * precision floating-point format. * * In 1991, Ken Turkowski implemented the conversions to and from * IEEE double-precision format, added more precision to the extended * conversions, and accommodated conversions involving +/- infinity, * NaN's, and denormalized numbers. * * $Id: portableio.c,v 2.6 1991/04/30 17:06:02 malcolm Exp $ * * $Log: portableio.c,v $ * Revision 2.6 91/04/30 17:06:02 malcolm */ #include#include #include #include "portableio.h" /**************************************************************** * Big/little-endian independent I/O routines. ****************************************************************/ int ReadByte(fp) FILE *fp; { int result; result = getc(fp) & 0xff; if (result & 0x80) result = result - 0x100; return result; } int Read16BitsLowHigh(fp) FILE *fp; { int first, second, result; first = 0xff & getc(fp); second = 0xff & getc(fp); result = (second << 8) + first; #ifndef THINK_C42 if (result & 0x8000) result = result - 0x10000; #endif /* THINK_C */ return(result); } int Read16BitsHighLow(fp) FILE *fp; { int first, second, result; first = 0xff & getc(fp); second = 0xff & getc(fp); result = (first << 8) + second; #ifndef THINK_C42 if (result & 0x8000) result = result - 0x10000; #endif /* THINK_C */ return(result); } void Write8Bits(fp, i) FILE *fp; int i; { putc(i&0xff,fp); } void Write16BitsLowHigh(fp, i) FILE *fp; int i; { putc(i&0xff,fp); putc((i>>8)&0xff,fp); } void Write16BitsHighLow(fp, i) FILE *fp; int i; { putc((i>>8)&0xff,fp); putc(i&0xff,fp); } int Read24BitsHighLow(fp) FILE *fp; { int first, second, third; int result; first = 0xff & getc(fp); second = 0xff & getc(fp); third = 0xff & getc(fp); result = (first << 16) + (second << 8) + third; if (result & 0x800000) result = result - 0x1000000; return(result); } #define Read32BitsLowHigh(f) Read32Bits(f) int Read32Bits(fp) FILE *fp; { int first, second, result; first = 0xffff & Read16BitsLowHigh(fp); second = 0xffff & Read16BitsLowHigh(fp); result = (second << 16) + first; #ifdef CRAY if (result & 0x80000000) result = result - 0x100000000; #endif /* CRAY */ return(result); } int Read32BitsHighLow(fp) FILE *fp; { int first, second, result; first = 0xffff & Read16BitsHighLow(fp); second = 0xffff & Read16BitsHighLow(fp); result = (first << 16) + second; #ifdef CRAY if (result & 0x80000000) result = result - 0x100000000; #endif return(result); } void Write32Bits(fp, i) FILE *fp; int i; { Write16BitsLowHigh(fp,(int)(i&0xffffL)); Write16BitsLowHigh(fp,(int)((i>>16)&0xffffL)); } void Write32BitsLowHigh(fp, i) FILE *fp; int i; { Write16BitsLowHigh(fp,(int)(i&0xffffL)); Write16BitsLowHigh(fp,(int)((i>>16)&0xffffL)); } void Write32BitsHighLow(fp, i) FILE *fp; int i; { Write16BitsHighLow(fp,(int)((i>>16)&0xffffL)); Write16BitsHighLow(fp,(int)(i&0xffffL)); } void ReadBytes(fp, p, n) FILE *fp; char *p; int n; { while (!feof(fp) && n-- > 0) *p++ = getc(fp); } void ReadBytesSwapped(fp, p, n) FILE *fp; char *p; int n; { register char *q = p; while (!feof(fp) && n-- > 0) *q++ = getc(fp); for (q--; p < q; p++, q--){ n = *p; *p = *q; *q = n; } } void WriteBytes(fp, p, n) FILE *fp; char *p; int n; { while (n-- > 0) putc(*p++, fp); } void WriteBytesSwapped(fp, p, n) FILE *fp; char *p; int n; { p += n-1; while (n-- > 0) putc(*p--, fp); } defdouble ReadIeeeFloatHighLow(fp) FILE *fp; { char bits[kFloatLength]; ReadBytes(fp, bits, kFloatLength); return ConvertFromIeeeSingle(bits); } defdouble ReadIeeeFloatLowHigh(fp) FILE *fp; { char bits[kFloatLength]; ReadBytesSwapped(fp, bits, kFloatLength); return ConvertFromIeeeSingle(bits); } defdouble ReadIeeeDoubleHighLow(fp) FILE *fp; { char bits[kDoubleLength]; ReadBytes(fp, bits, kDoubleLength); return ConvertFromIeeeDouble(bits); } defdouble ReadIeeeDoubleLowHigh(fp) FILE *fp; { char bits[kDoubleLength]; ReadBytesSwapped(fp, bits, kDoubleLength); return ConvertFromIeeeDouble(bits); } defdouble ReadIeeeExtendedHighLow(fp) FILE *fp; { char bits[kExtendedLength]; ReadBytes(fp, bits, kExtendedLength); return ConvertFromIeeeExtended(bits); } defdouble ReadIeeeExtendedLowHigh(fp) FILE *fp; { char bits[kExtendedLength]; ReadBytesSwapped(fp, bits, kExtendedLength); return ConvertFromIeeeExtended(bits); } void WriteIeeeFloatLowHigh(fp, num) FILE *fp; defdouble num; { char bits[kFloatLength]; ConvertToIeeeSingle(num,bits); WriteBytesSwapped(fp,bits,kFloatLength); } void WriteIeeeFloatHighLow(fp, num) FILE *fp; defdouble num; { char bits[kFloatLength]; ConvertToIeeeSingle(num,bits); WriteBytes(fp,bits,kFloatLength); } void WriteIeeeDoubleLowHigh(fp, num) FILE *fp; defdouble num; { char bits[kDoubleLength]; ConvertToIeeeDouble(num,bits); WriteBytesSwapped(fp,bits,kDoubleLength); } void WriteIeeeDoubleHighLow(fp, num) FILE *fp; defdouble num; { char bits[kDoubleLength]; ConvertToIeeeDouble(num,bits); WriteBytes(fp,bits,kDoubleLength); } void WriteIeeeExtendedLowHigh(fp, num) FILE *fp; defdouble num; { char bits[kExtendedLength]; ConvertToIeeeExtended(num,bits); WriteBytesSwapped(fp,bits,kExtendedLength); } void WriteIeeeExtendedHighLow(fp, num) FILE *fp; defdouble num; { char bits[kExtendedLength]; ConvertToIeeeExtended(num,bits); WriteBytes(fp,bits,kExtendedLength); } enum e_byte_order DetermineByteOrder() { char s[ sizeof(long) + 1 ]; union { long longval; char charval[ sizeof(long) ]; } probe; probe.longval = 0x41424344L; /* ABCD in ASCII */ strncpy( s, probe.charval, sizeof(long) ); s[ sizeof(long) ] = '\0'; /* fprintf( stderr, "byte order is %s\n", s ); */ if ( strcmp(s, "ABCD") == 0 ) return order_bigEndian; else if ( strcmp(s, "DCBA") == 0 ) return order_littleEndian; else return order_unknown; } void SwapBytesInWords( short *loc, int words ) { int i; short thisval; char *dst, *src; src = (char *) &thisval; for ( i = 0; i < words; i++ ) { thisval = *loc; dst = (char *) loc++; dst[0] = src[1]; dst[1] = src[0]; } }