From: Paul Eggert Date: Wed, 16 Apr 1997 21:02:57 +0000 (+0000) Subject: GNU tar 1.12 X-Git-Url: https://git.dogcows.com/gitweb?p=chaz%2Ftar;a=commitdiff_plain;h=cee0eec6d2412e5424b4ddbf7fa6db5098787e38 GNU tar 1.12 --- diff --git a/src/arith.h b/src/arith.h new file mode 100644 index 0000000..e8c2ace --- /dev/null +++ b/src/arith.h @@ -0,0 +1,123 @@ +/* Simple arithmetic for numbers greater than a long int, for GNU tar. + Copyright (C) 1996, 1997 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* Also, see comments at beginning of arith.c. */ + +#define BITS_PER_BYTE 8 /* number of bits in each sizeof unit */ +#define BITS_PER_TARLONG 42 /* wanted number of bits in each tarlong */ + +/* In all cases, tarlong is the proper type for a big number. + + For simulated arithmetic, SUPERDIGIT is the base, TARLONG_FORMAT is the + format to print a single super-digit filled with zeroes to the left, and + BITS_PER_SUPERDIGIT is the smallest number of bits required to fully + represent each super-digit. LONGS_PER_TARLONG says how many longs are + required for a full tarlong, and SIZEOF_TARLONG is the size of a tarlong + in bytes. + + For straight compiler arithmetic, SUPERDIGIT is zero and TARLONG_FORMAT + is the format to directly print a tarlong (without zero-filling). + + The values of SIZEOF_LONG_LONG and SIZEOF_UNSIGNED_LONG, below, are + obtained through the configuration process. */ + +#if BITS_PER_BYTE * SIZEOF_UNSIGNED_LONG >= BITS_PER_TARLONG +# define SUPERDIGIT 0 +# define TARLONG_FORMAT "%uld" +typedef unsigned long tarlong; +#else +# if BITS_PER_BYTE * SIZEOF_LONG_LONG >= BITS_PER_TARLONG + 1 +# define SUPERDIGIT 0 +# define TARLONG_FORMAT "%lld" +typedef long long tarlong; +# else +# if BITS_PER_BYTE * SIZEOF_UNSIGNED_LONG >= 64 +# define SUPERDIGIT 1000000000L +# define BITS_PER_SUPERDIGIT 29 +# define TARLONG_FORMAT "%09uld" +# else +# if BITS_PER_BYTE * SIZEOF_UNSIGNED_LONG >= 32 +# define SUPERDIGIT 10000L +# define BITS_PER_SUPERDIGIT 14 +# define TARLONG_FORMAT "%04uld" +# endif +# endif +# endif +#endif + +#if SUPERDIGIT + +# define LONGS_PER_TARLONG \ + ((BITS_PER_TARLONG + BITS_PER_SUPERDIGIT - 1) / BITS_PER_SUPERDIGIT) +# define SIZEOF_TARLONG (LONGS_PER_TARLONG * sizeof (unsigned long)) + +/* The NEC EWS 4.2 C compiler gets confused by a pointer to a typedef that + is an array. So we wrap the array into a struct. (Pouah!) */ + +struct tarlong +{ + unsigned long digit[LONGS_PER_TARLONG]; +}; + +typedef struct tarlong tarlong; + +int zerop_tarlong_helper PARAMS ((unsigned long *)); +int lessp_tarlong_helper PARAMS ((unsigned long *, unsigned long *)); +void clear_tarlong_helper PARAMS ((unsigned long *)); +void add_to_tarlong_helper PARAMS ((unsigned long *, int)); +void mult_tarlong_helper PARAMS ((unsigned long *, int)); +void print_tarlong_helper PARAMS ((unsigned long *, FILE *)); + +# define zerop_tarlong(Accumulator) \ + zerop_tarlong_helper (&(Accumulator).digit[0]) + +# define lessp_tarlong(First, Second) \ + lessp_tarlong_helper (&(First).digit[0], &(Second).digit[0]) + +# define clear_tarlong(Accumulator) \ + clear_tarlong_helper (&(Accumulator).digit[0]) + +# define add_to_tarlong(Accumulator, Value) \ + add_to_tarlong_helper (&(Accumulator).digit[0], (Value)) + +# define mult_tarlong(Accumulator, Value) \ + mult_tarlong_helper (&(Accumulator).digit[0], (Value)) + +# define print_tarlong(Accumulator, File) \ + print_tarlong_helper (&(Accumulator).digit[0], (File)) + +#else /* not SUPERDIGIT */ + +# define zerop_tarlong(Accumulator) \ + ((Accumulator) == 0) + +# define lessp_tarlong(First, Second) \ + ((First) < (Second)) + +# define clear_tarlong(Accumulator) \ + ((Accumulator) = 0) + +# define add_to_tarlong(Accumulator, Value) \ + ((Accumulator) += (Value)) + +# define mult_tarlong(Accumulator, Value) \ + ((Accumulator) *= (Value)) + +# define print_tarlong(Accumulator, File) \ + (fprintf ((File), TARLONG_FORMAT, (Accumulator))) + +#endif /* not SUPERDIGIT */