view src/cdrom/SDL_syscdrom.h @ 2752:edd2839b36f7

http://sources.redhat.com/ml/newlib/2002/msg00230.html Stephen L Moshier wrote: > > pow(x,y) returns 0 when x is very close to -1.0 and y is very large. > The following test program prints > > pow(1.0000000000000002e+00 4.5035996273704970e+15) = 2.7182818284590455e+00 > pow(-1.0000000000000002e+00 4.5035996273704970e+15) =0.0000000000000000e+00 > pow(9.9999999999999978e-01 4.5035996273704970e+15) = 3.6787944117144222e-01 > pow(-9.9999999999999978e-01 4.5035996273704970e+15) = 0.0000000000000000e+00 > > which is incorrect for the negative arguments raised to an odd integer > power. > > ----- > double pow (double, double); > > int > main () > { > double x, y, z; > > x = 1.0 + pow (2.0, -52.0); > y = 1.0 + pow (2.0, 52.0); > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > x = -x; > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > x = 1.0 - pow (2.0, -52.0); > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > x = -x; > z = pow (x, y); > printf ("pow(%.16e %.16e) = %.16e\n", x, y, z); > } > ----- > > Here is a patch for newlib/libm/math/epow.c: Patch checked in and duplicated for ef_pow.c. Thanks. -- Jeff J.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 15 Sep 2008 04:31:30 +0000
parents 542c78b6fb12
children 99210400e8b9
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is SDL_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.

    This 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 this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* This is the system specific header for the SDL CD-ROM API */

/* Structure of CD audio control functions */
extern struct CDcaps
{
    /* Get the name of the specified drive */
    const char *(*Name) (int drive);

    /* Open the specified drive, returning a drive id, or -1 on error */
    int (*Open) (int drive);

    /* Get table-of-contents (number of tracks + track info) for disk.
       The TOC information should be stored in the cdrom structure.
       This function should return 0 on success, or -1 on error.
     */
    int (*GetTOC) (SDL_CD * cdrom);

    /* Return the current status and play position, in frames, of the
       drive.  'position' may be NULL, and if so, should be ignored.
     */
      CDstatus(*Status) (SDL_CD * cdrom, int *position);

    /* Play from frame 'start' to 'start+len' */
    int (*Play) (SDL_CD * cdrom, int start, int len);

    /* Pause play */
    int (*Pause) (SDL_CD * cdrom);

    /* Resume play */
    int (*Resume) (SDL_CD * cdrom);

    /* Stop play */
    int (*Stop) (SDL_CD * cdrom);

    /* Eject the current disk */
    int (*Eject) (SDL_CD * cdrom);

    /* Close the specified drive */
    void (*Close) (SDL_CD * cdrom);
} SDL_CDcaps;

/* The number of available CD-ROM drives on the system */
extern int SDL_numcds;

/* Function to scan the system for CD-ROM drives and fill SDL_CDcaps.
 * This function should set SDL_numcds to the number of available CD
 * drives.  Drive 0 should be the system default CD-ROM.
 * It should return 0, or -1 on an unrecoverable fatal error.
*/
extern int SDL_SYS_CDInit(void);

/* Function to perform any system-specific CD-ROM related cleanup */
extern void SDL_SYS_CDQuit(void);

/* vi: set ts=4 sw=4 expandtab: */