| /* Copyright (C) 1992, 1997, 1999 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. */ |
| |
| /* |
| * Copyright (c) 1990 Regents of the University of California. |
| * All rights reserved. |
| * |
| * This code is derived from software contributed to Berkeley by |
| * Chris Torek. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 4. Neither the name of the University nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include <stdlib.h> |
| |
| /* Return the `div_t' representation of NUMER over DENOM. */ |
| div_t |
| div (numer, denom) |
| int numer, denom; |
| { |
| div_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; |
| } |