sdl2_frt/src/libm/s_floor.c
Philipp Wiesemann 0e45984fa0 Fixed crash if initialization of EGL failed but was tried again later.
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
2015-06-21 17:33:46 +02:00

97 lines
2.6 KiB
C

/* @(#)s_floor.c 5.1 93/09/24 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static const char rcsid[] =
"$NetBSD: s_floor.c,v 1.8 1995/05/10 20:47:20 jtc Exp $";
#endif
/*
* floor(x)
* Return x rounded toward -inf to integral value
* Method:
* Bit twiddling.
* Exception:
* Inexact flag raised if x not equal to floor(x).
*/
#include "math_libm.h"
#include "math_private.h"
#ifdef __STDC__
static const double huge_val = 1.0e300;
#else
static double huge_val = 1.0e300;
#endif
libm_hidden_proto(floor)
#ifdef __STDC__
double floor(double x)
#else
double floor(x)
double x;
#endif
{
int32_t i0, i1, j0;
u_int32_t i, j;
EXTRACT_WORDS(i0, i1, x);
j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
if (j0 < 20) {
if (j0 < 0) { /* raise inexact if x != 0 */
if (huge_val + x > 0.0) { /* return 0*sign(x) if |x|<1 */
if (i0 >= 0) {
i0 = i1 = 0;
} else if (((i0 & 0x7fffffff) | i1) != 0) {
i0 = 0xbff00000;
i1 = 0;
}
}
} else {
i = (0x000fffff) >> j0;
if (((i0 & i) | i1) == 0)
return x; /* x is integral */
if (huge_val + x > 0.0) { /* raise inexact flag */
if (i0 < 0)
i0 += (0x00100000) >> j0;
i0 &= (~i);
i1 = 0;
}
}
} else if (j0 > 51) {
if (j0 == 0x400)
return x + x; /* inf or NaN */
else
return x; /* x is integral */
} else {
i = ((u_int32_t) (0xffffffff)) >> (j0 - 20);
if ((i1 & i) == 0)
return x; /* x is integral */
if (huge_val + x > 0.0) { /* raise inexact flag */
if (i0 < 0) {
if (j0 == 20)
i0 += 1;
else {
j = i1 + (1 << (52 - j0));
if (j < (u_int32_t) i1)
i0 += 1; /* got a carry */
i1 = j;
}
}
i1 &= (~i);
}
}
INSERT_WORDS(x, i0, i1);
return x;
}
libm_hidden_def(floor)