Copyright 2011-2013, 2018 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of either:
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your
option) any later version.
or
* the GNU General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any
later version.
or both in parallel, as here.
The GNU MP 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 General Public License
for more details.
You should have received copies of the GNU General Public License and the
GNU Lesser General Public License along with the GNU MP Library. If not,
see https://www.gnu.org/licenses/.
This is "mini-gmp", a small implementation of a subset of GMP's mpn,
mpz and mpq interfaces.
It is intended for applications which need arithmetic on numbers
larger than a machine word, but which don't need to handle very large
numbers very efficiently. Those applications can include a copy of
mini-gmp to get a GMP-compatible interface with small footprint. One
can also arrange for optional linking with the real GMP library, using
mini-gmp as a fallback when for some reason GMP is not available, or
not desired as a dependency.
The supported GMP subset of the mpn and mpz interfaces is declared in
mini-gmp.h, and implemented in mini-gmp.c. The implemented
functions are fully compatible with the corresponding GMP functions,
as specified in the GMP manual, with a few exceptions:
mpz_export and mpz_import support only NAILS = 0.
The REALLOC_FUNC and FREE_FUNC registered with
mp_set_memory_functions does not get the correct size of the
allocated block in the corresponding argument. mini-gmp always
passes zero for these rarely used arguments.
When mpz_get_str allocates the block, it can be longer than needed.
The performance target for mini-gmp is to be at most 10 times slower
than the real GMP library, for numbers of size up to a few hundred
bits. No asymptotically fast algorithms are included in mini-gmp, so
it will be many orders of magnitude slower than GMP for very large
numbers.
The supported GMP subset of the mpq layer is declared in mini-mpq.h,
and implemented in mini-mpq.c.
You should never "install" mini-gmp. Applications can either just
#include mini-gmp.c (but then, beware that it defines several macros
and functions outside of the advertised interface), and if needed
#include mini-mpq.c in a later line (order is important). Or compile
mini-gmp.c and mini-mpq.c as separate compilation units, and use the
declarations in mini-gmp.h and mini-mpq.h.
The tests subdirectory contains a testsuite. To use it, you need GMP
and GNU make. Just run make check in the tests directory. If the
hard-coded compiler settings are not right, you have to either edit the
Makefile or pass overriding values on the make command line (e.g.,
make CC=cc check).
The initial version of mini-gmp was put together by Niels Möller
<nisse@lysator.liu.se>, with a fair amount of copy-and-paste from the
GMP sources.
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