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Thu Mar 14 06:01:07 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu>
* string/strnlen.c: New file. * string/Makefile (routines): Add strnlen. * string/string.h [__USE_GNU] (strnlen): Declare new function. [__OPTIMIZE__]: Define extern inline implementation of it. * stdlib/erand48_r.c: Use __mpn_construct_double instead of ldexp and addition, to avoid using anything from -lm. Mon Mar 4 21:57:14 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/unix/sysv/linux/m68k/Makefile: New file. * sysdeps/unix/sysv/linux/m68k/sysdep.h (SYS_ify): Redefine. (CALL_MCOUNT): New macro, empty unless [PROF]. (ENTRY): Do CALL_MCOUNT just after the label. (JUMPTARGET): New macro. (SYSCALL_ERROR_HANDLER): Fix syntax. Thu Mar 14 04:20:48 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * sysdeps/unix/sysv/linux/init-first.c (init): Call `__personality' function instead of using inline asm i386 syscall. * sysdeps/unix/sysv/linux/syscalls.list: Add personality syscall. * posix/unistd.h [__USE_BSD]: Declare usleep. * misc/efgcvt.c (MAXDIG): New macro computed from <floats.h> constants. (fcvt, ecvt): Use it for buffer size. * stdlib/drand48-iter.c (__drand48_iterate): Use u_int64_t instead of conditionalizing long vs long long. * stdlib/drand48-iter.c (__drand48_iterate): Don't check for null pointers; never return EFAULT. * stdlib/drand48_r.c (drand48_r): Likewise. * stdlib/erand48_r.c (erand48_r): Likewise.
This commit is contained in:
@ -17,9 +17,15 @@ License along with the GNU C Library; see the file COPYING.LIB. If
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not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include <errno.h>
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#include <math.h>
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#include <stdlib.h>
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#include "gmp.h"
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#include "gmp-mparam.h"
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#include <float.h>
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/* Function to construct a floating point number from an MP integer
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containing the fraction bits, a base 2 exponent, and a sign flag. */
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extern double __mpn_construct_double (mp_srcptr mpn, int exponent, int neg);
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int
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erand48_r (xsubi, buffer, result)
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@ -27,26 +33,30 @@ erand48_r (xsubi, buffer, result)
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struct drand48_data *buffer;
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double *result;
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{
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int i;
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/* Be generous for the arguments, detect some errors. */
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if (result == NULL)
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{
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errno = EFAULT;
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return -1;
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}
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mp_limb mpn[(3 * sizeof (unsigned short int) + sizeof (mp_limb) - 1)
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/ sizeof (mp_limb)];
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/* Compute next state. */
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if (__drand48_iterate (xsubi, buffer) < 0)
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return -1;
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*result = 0.0;
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for (i = 4 / sizeof (unsigned short int); i >= 0; --i)
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{
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double factor = ldexp (1.0, (i - 6) * sizeof (unsigned short int));
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/* Build a 48-bit mpn containing the 48 random bits. */
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*result += factor * (double) xsubi[i];
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}
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#if BITS_PER_MP_LIMB == 64
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mpn[0] = (xsubi[0] << 32) | (xsubi[1] << 16) | xsubi[2];
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#elif BITS_PER_MP_LIMB == 32
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mpn[0] = (xsubi[1] << 16) | xsubi[2];
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mpn[1] = xsubi[0];
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#else
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#error "BITS_PER_MP_LIMB value not handled"
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#endif
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/* Shift them up so they are most significant bits of the fraction. */
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__mpn_lshift (mpn, mpn, sizeof mpn / sizeof mpn[0], DBL_MANT_DIG - 48);
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/* Construct a positive double using those bits for the fractional part,
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and a zero exponent so the resulting FP number is [0.0,1.0). */
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*result = __mpn_construct_double (mpn, 0, 0);
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return 0;
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}
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