From 84fec7f904ee0951c85803071b53002b6bd6e93b Mon Sep 17 00:00:00 2001 From: Christian Heller Date: Sun, 21 Jul 2013 05:54:42 +0200 Subject: [PATCH] Use bit-shifting instead of bizarre arithmetics on UCHAR_MAX for readwrite library. Also apply new code style idea. --- src/readwrite.c | 55 +++++++++++++++++++++++++------------------------ 1 file changed, 28 insertions(+), 27 deletions(-) diff --git a/src/readwrite.c b/src/readwrite.c index cdee90b..8afcfb5 100644 --- a/src/readwrite.c +++ b/src/readwrite.c @@ -3,34 +3,35 @@ #include "readwrite.h" #include #include -#include -static const uint16_t uchar_s = UCHAR_MAX + 1; +extern uint16_t read_uint16_bigendian( FILE * file ) +{ + uint16_t x; + x = (uint16_t) fgetc(file) << 8 ; + x = x + (uint16_t) fgetc(file) ; + return x; +} -extern uint16_t read_uint16_bigendian(FILE * file) { - unsigned char a = fgetc(file); - unsigned char b = fgetc(file); - return (a * uchar_s) + b; } +extern uint32_t read_uint32_bigendian( FILE * file ) +{ + uint32_t x; + x = (uint32_t) fgetc(file) << 24 ; + x = x + ( (uint32_t) fgetc(file) << 16 ) ; + x = x + ( (uint32_t) fgetc(file) << 8 ) ; + x = x + (uint32_t) fgetc(file) ; + return x; +} -extern uint32_t read_uint32_bigendian(FILE * file) { - unsigned char a = fgetc(file); - unsigned char b = fgetc(file); - unsigned char c = fgetc(file); - unsigned char d = fgetc(file); - return (a * uchar_s * uchar_s * uchar_s) + (b * uchar_s * uchar_s) + (c * uchar_s) + d; } +extern void write_uint16_bigendian( uint16_t x, FILE * file ) +{ + fputc( x >> 8, file ); + fputc( x & 0xFF, file ); +} -extern void write_uint16_bigendian(uint16_t x, FILE * file) { - unsigned char a = x / uchar_s; - unsigned char b = x % uchar_s; - fputc(a, file); - fputc(b, file); } - -extern void write_uint32_bigendian(uint32_t x, FILE * file) { - unsigned char a = x / (uchar_s * uchar_s * uchar_s); - unsigned char b = (x - (a * uchar_s * uchar_s * uchar_s)) / (uchar_s * uchar_s); - unsigned char c = (x - ((a * uchar_s * uchar_s * uchar_s) + (b * uchar_s * uchar_s))) / uchar_s; - unsigned char d = x % uchar_s; - fputc(a, file); - fputc(b, file); - fputc(c, file); - fputc(d, file); } +extern void write_uint32_bigendian( uint32_t x, FILE * file ) +{ + fputc( ( x >> 24 ) & 0xFF, file); + fputc( ( x >> 16 ) & 0xFF, file); + fputc( ( x >> 8 ) & 0xFF, file); + fputc( x & 0xFF, file); +} -- 2.30.2