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[/] [openrisc/] [trunk/] [gnu-src/] [newlib-1.18.0/] [newlib/] [libc/] [machine/] [powerpc/] [strtoufix16.c] - Rev 301
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/* FUNCTION <<strtoufix16>>, <<strtoufix32>>, <<strtoufix64>>---string to signed fixed point INDEX strtoufix16 INDEX strtoufix32 INDEX strtoufix64 INDEX _strtoufix16_r INDEX _strtoufix32_r INDEX _strtoufix64_r ANSI_SYNOPSIS #include <stdlib.h> __uint16_t strtoufix16 (const char *<[s]>, char **<[ptr]>); __uint32_t strtoufix32 (const char *<[s]>, char **<[ptr]>); __uint64_t strtoufix64 (const char *<[s]>, char **<[ptr]>); __uint16_t _strtoufix16_r (void *<[reent]>, const char *<[s]>, char **<[ptr]>); __uint32_t _strtoufix32_r (void *<[reent]>, const char *<[s]>, char **<[ptr]>); __uint64_t _strtoufix64_r (void *<[reent]>, const char *<[s]>, char **<[ptr]>); TRAD_SYNOPSIS #include <stdlib.h> __uint16_t strtoufix16 (<[s]>, <[ptr]>) char *<[s]>; char **<[ptr]>; __uint32_t strtoufix32 (<[s]>, <[ptr]>) char *<[s]>; char **<[ptr]>; __uint64_t strtoufix64 (<[s]>, <[ptr]>) char *<[s]>; char **<[ptr]>; __uint16_t _strtoufix16_r (<[reent]>, <[s]>, <[ptr]>) char *<[reent]>; char *<[s]>; char **<[ptr]>; __uint32_t _strtoufix32_r (<[reent]>, <[s]>, <[ptr]>) char *<[reent]>; char *<[s]>; char **<[ptr]>; __uint64_t _strtoufix64_r (<[reent]>, <[s]>, <[ptr]>) char *<[reent]>; char *<[s]>; char **<[ptr]>; DESCRIPTION The function <<strtoufix16>> converts the string <<*<[s]>>> to a fixed-point 16-bits fraction representation. The function follows the same rules as <<strtod>>. The substring converted is the longest initial subsequence of <[s]>, beginning with the first non-whitespace character, that has the format: .[+|-]<[digits]>[.][<[digits]>][(e|E)[+|-]<[digits]>] The substring contains no characters if <[s]> is empty, consists entirely of whitespace, or if the first non-whitespace character is something other than <<+>>, <<->>, <<.>>, or a digit. If the substring is empty, no conversion is done, and the value of <[s]> is stored in <<*<[ptr]>>>. Otherwise, the substring is converted, and a pointer to the final string (which will contain at least the terminating null character of <[s]>) is stored in <<*<[ptr]>>>. If you want no assignment to <<*<[ptr]>>>, pass a null pointer as <[ptr]>. <<strtoufix32>> is identical to <<strtoufix16>> except that it converts to fixed-point 32-bit fraction representation. <<strtoufix64>> is also similar, except that it converts to fixed-point 64-bit fraction. The alternate functions <<_strtoufix16_r>>, <<_strtoufix32_r>>, and <<_strtoufix64_r>> are reentrant versions. The extra argument <[reent]> is a pointer to a reentrancy structure. RETURNS The functions return the converted substring value, if any. If no conversion can be performed, then 0 is returned. If the converted value is a NaN, 0 is returned and errno is set to <<EDOM>>. If the converted value exceeds the maximum positive unsigned fixed-point value, the output value is saturated to the maximum value and <<ERANGE>> is stored in errno. If the converted value is less than 0, then the output is saturated to 0 and <<ERANGE>> is stored in errno. Otherwise, the converted value is returned in the specified fixed-point format. PORTABILITY <<strtoufix16>>, <<strtoufix32>>, and <<strtoufix64>> are non-standard. The OS subroutines of <<strtod>> are required. */ #ifdef __SPE__ #include <_ansi.h> #include <limits.h> #include <errno.h> #include <stdlib.h> #include <reent.h> #include "vfieeefp.h" /* * Convert a string to a fixed-point 16-bit value. * * Ignores `locale' stuff. */ __uint16_t _DEFUN (_strtoufix16_r, (rptr, nptr, endptr), struct _reent *rptr _AND _CONST char *nptr _AND char **endptr) { union double_union dbl; unsigned long tmp, tmp2, result; int exp, negexp; dbl.d = _strtod_r (rptr, nptr, endptr); /* treat NAN as domain error, +/- infinity as saturation */ if (!finite(dbl.d)) { if (isnan (dbl.d)) { rptr->_errno = EDOM; return 0; } rptr->_errno = ERANGE; if (word0(dbl) & Sign_bit) return 0; return USHRT_MAX; } /* check for normal saturation */ if (dbl.d >= 1.0) { rptr->_errno = ERANGE; return USHRT_MAX; } else if (dbl.d < 0) { rptr->_errno = ERANGE; return 0; } /* otherwise we have normal postive number in range */ /* strip off exponent */ exp = ((word0(dbl) & Exp_mask) >> Exp_shift) - Bias; negexp = -exp; if (negexp > 16) return 0; /* add in implicit normalized bit */ tmp = word0(dbl) | Exp_msk1; /* remove exponent and sign */ tmp <<= Ebits; /* perform rounding */ tmp2 = tmp + (1 << (negexp + 14)); result = tmp2 >> (negexp + 15); /* if rounding causes carry, must add carry bit in */ if (tmp2 < tmp) { if (negexp == 0) { /* we have overflow which means saturation */ rptr->_errno = ERANGE; return USHRT_MAX; } result |= (1 << (16 - negexp)); } return (__uint16_t)result; } #ifndef _REENT_ONLY __uint16_t _DEFUN (strtoufix16, (s, ptr, base), _CONST char *s _AND char **ptr) { return _strtoufix16_r (_REENT, s, ptr); } #endif #endif /* __SPE__ */
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