diff options
Diffstat (limited to 'libc')
| -rw-r--r-- | libc/stdlib/Makefile | 4 | ||||
| -rw-r--r-- | libc/stdlib/ldiv.c | 78 | ||||
| -rw-r--r-- | libc/stdlib/lldiv.c | 63 |
3 files changed, 119 insertions, 26 deletions
diff --git a/libc/stdlib/Makefile b/libc/stdlib/Makefile index 878d2bd03..02dd8887e 100644 --- a/libc/stdlib/Makefile +++ b/libc/stdlib/Makefile @@ -82,8 +82,8 @@ MSRC2 = atexit.c MOBJ2 = atexit.o on_exit.o __exit_handler.o exit.o CSRC = abort.c getenv.c mkdtemp.c mktemp.c realpath.c mkstemp.c mkstemp64.c \ - rand.c random.c random_r.c setenv.c system.c div.c ldiv.c getpt.c \ - ptsname.c grantpt.c unlockpt.c gcvt.c drand48-iter.c jrand48.c \ + rand.c random.c random_r.c setenv.c system.c div.c ldiv.c lldiv.c \ + getpt.c ptsname.c grantpt.c unlockpt.c gcvt.c drand48-iter.c jrand48.c \ jrand48_r.c lrand48.c lrand48_r.c mrand48.c mrand48_r.c nrand48.c \ nrand48_r.c rand_r.c srand48.c srand48_r.c seed48.c seed48_r.c \ valloc.c diff --git a/libc/stdlib/ldiv.c b/libc/stdlib/ldiv.c index 230b6a944..c66470fb2 100644 --- a/libc/stdlib/ldiv.c +++ b/libc/stdlib/ldiv.c @@ -1,32 +1,62 @@ -/* vi: set sw=4 ts=4: */ -/* ldiv for uClibc - * - * Copyright (C) 2000 by Lineo, inc. and Erik Andersen - * Copyright (C) 2000,2001 by Erik Andersen <andersen@uclibc.org> - * Written by Erik Andersen <andersen@uclibc.org> - * - * This program 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 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 Library General Public License - * for more details. - * - * You should have received a copy of the GNU Library 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 - */ +/* Copyright (C) 1992, 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <features.h> #include <stdlib.h> -ldiv_t ldiv(long numer, long denom) + +/* Return the `ldiv_t' representation of NUMER over DENOM. */ +ldiv_t +ldiv (long int numer, long int denom) { ldiv_t result; + result.quot = numer / denom; - result.rem = numer - (result.quot * denom); - return(result); + result.rem = numer % denom; + + /* The ANSI standard says that |QUOT| <= |NUMER / DENOM|, where + NUMER / DENOM is to be computed in infinite precision. In + other words, we should always truncate the quotient towards + zero, never -infinity. Machine division and remainer may + work either way when one or both of NUMER or DENOM is + negative. If only one is negative and QUOT has been + truncated towards -infinity, REM will have the same sign as + DENOM and the opposite sign of NUMER; if both are negative + and QUOT has been truncated towards -infinity, REM will be + positive (will have the opposite sign of NUMER). These are + considered `wrong'. If both are NUM and DENOM are positive, + RESULT will always be positive. This all boils down to: if + NUMER >= 0, but REM < 0, we got the wrong answer. In that + case, to get the right answer, add 1 to QUOT and subtract + DENOM from REM. */ + + if (numer >= 0 && result.rem < 0) + { + ++result.quot; + result.rem -= denom; + } + + return result; } +#if __WORDSIZE == 64 +#undef imaxdiv +weak_alias (ldiv, imaxdiv); +#endif + diff --git a/libc/stdlib/lldiv.c b/libc/stdlib/lldiv.c new file mode 100644 index 000000000..2b382db6c --- /dev/null +++ b/libc/stdlib/lldiv.c @@ -0,0 +1,63 @@ +/* `long long int' divison with remainder. + Copyright (C) 1992, 1996, 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#define _GNU_SOURCE +#include <features.h> +#include <stdlib.h> + + +/* Return the `lldiv_t' representation of NUMER over DENOM. */ +lldiv_t +lldiv (long long int numer, long long int denom) +{ + lldiv_t result; + + result.quot = numer / denom; + result.rem = numer % denom; + + /* The ANSI standard says that |QUOT| <= |NUMER / DENOM|, where + NUMER / DENOM is to be computed in infinite precision. In + other words, we should always truncate the quotient towards + zero, never -infinity. Machine division and remainer may + work either way when one or both of NUMER or DENOM is + negative. If only one is negative and QUOT has been + truncated towards -infinity, REM will have the same sign as + DENOM and the opposite sign of NUMER; if both are negative + and QUOT has been truncated towards -infinity, REM will be + positive (will have the opposite sign of NUMER). These are + considered `wrong'. If both are NUM and DENOM are positive, + RESULT will always be positive. This all boils down to: if + NUMER >= 0, but REM < 0, we got the wrong answer. In that + case, to get the right answer, add 1 to QUOT and subtract + DENOM from REM. */ + + if (numer >= 0 && result.rem < 0) + { + ++result.quot; + result.rem -= denom; + } + + return result; +} + +#if __WORDSIZE != 64 +#undef imaxdiv +weak_alias (lldiv, imaxdiv); +#endif + |