diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/internal/floatscan.c | 439 | ||||
| -rw-r--r-- | src/internal/floatscan.h | 8 | ||||
| -rw-r--r-- | src/internal/shgetc.c | 24 | ||||
| -rw-r--r-- | src/internal/shgetc.h | 25 | ||||
| -rw-r--r-- | src/internal/stdio_impl.h | 2 | ||||
| -rw-r--r-- | src/stdlib/strtod.c | 30 | ||||
| -rw-r--r-- | src/stdlib/strtof.c | 6 | ||||
| -rw-r--r-- | src/stdlib/strtold.c | 96 | 
8 files changed, 527 insertions, 103 deletions
| diff --git a/src/internal/floatscan.c b/src/internal/floatscan.c new file mode 100644 index 00000000..b2313293 --- /dev/null +++ b/src/internal/floatscan.c @@ -0,0 +1,439 @@ +#include <stdint.h> +#include <stdio.h> +#include <math.h> +#include <float.h> +#include <limits.h> +#include <errno.h> + +#include "shgetc.h" +#include "floatscan.h" + +#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 + +#define LD_B1B_DIG 2 +#define LD_B1B_MAX 9007199, 254740991 +#define KMAX 128 + +#else /* LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 */ + +#define LD_B1B_DIG 3 +#define LD_B1B_MAX 18, 446744073, 709551615 +#define KMAX 2048 + +#endif + +#define MASK (KMAX-1) + + +static long long scanexp(FILE *f, int pok) +{ +	int c; +	int x; +	long long y; +	int neg = 0; +	 +	c = shgetc(f); +	if (c=='+' || c=='-') { +		neg = (c=='-'); +		c = shgetc(f); +		if (c-'0'>=10U && pok) shunget(f); +	} +	if (c-'0'>=10U) { +		shunget(f); +		return LLONG_MIN; +	} +	for (x=0; c-'0'<10U && x<INT_MAX/10; c = shgetc(f)) +		x = 10*x + c-'0'; +	for (y=x; c-'0'<10U && x<LLONG_MAX/100; c = shgetc(f)) +		y = 10*y + c-'0'; +	for (; c-'0'<10U; c = shgetc(f)); +	shunget(f); +	return neg ? -y : y; +} + + +static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int pok) +{ +	uint32_t x[KMAX]; +	static const uint32_t th[] = { LD_B1B_MAX }; +	int i, j, k, a, z; +	long long lrp=-1, dc=0; +	long long e10=0; +	int gotdig = 0; +	int rp; +	int e2; +	long double y; +	long double frac=0; +	long double bias=0; + +	j=0; +	k=0; + +	/* Don't let leading zeros consume buffer space */ +	for (; c=='0'; c = shgetc(f)) gotdig=1; + +	x[0] = 0; +	for (; c-'0'<10U || c=='.'; c = shgetc(f)) { +		if (c == '.') { +			if (lrp!=-1) break; +			lrp = dc; +		} else if (k < KMAX-2) { +			dc++; +			if (j) x[k] = x[k]*10 + c-'0'; +			else x[k] = c-'0'; +			if (++j==9) { +				k++; +				j=0; +			} +			gotdig=1; +		} else { +			dc++; +			if (c!='0') x[KMAX-3] |= 1; +		} +	} +	if (lrp==-1) lrp=dc; + +	if (gotdig && (c|32)=='e') { +		e10 = scanexp(f, pok); +		if (e10 == LLONG_MIN) { +			if (pok) { +				shunget(f); +			} else { +				shlim(f, 0); +				return 0; +			} +			e10 = 0; +		} +		lrp += e10; +	} else if (c>=0) { +		shunget(f); +	} +	if (!gotdig) { +		errno = EINVAL; +		shlim(f, 0); +		return 0; +	} + +	if (!x[0]) +		return sign * 0.0; +	if (lrp==dc && (!k || (k==1 && !j)) && (bits>30 || x[0]>>bits==0)) +		return sign * (long double)x[0]; +	if (lrp > -emin/2) { +		errno = ERANGE; +		return sign * LDBL_MAX * LDBL_MAX; +	} +	if (lrp < emin-2*LDBL_MANT_DIG) { +		errno = ERANGE; +		return sign * LDBL_MIN * LDBL_MIN; +	} + +	if (k<KMAX && j) { +		for (; j<9; j++) x[k]*=10; +		k++; +		j=0; +	} + +	a = 0; +	z = k; +	e2 = 0; +	rp = lrp; + +	if (rp % 9) { +		static const int p10s[] = { +			100000000, 10000000, 1000000, 100000, +			10000, 1000, 100, 10 +		}; +		int rpm9 = rp>=0 ? rp%9 : rp%9+9; +		int p10 = p10s[rpm9-1]; +		uint32_t carry = 0; +		for (k=a; k!=z; k++) { +			uint32_t tmp = x[k] % p10; +			x[k] = x[k]/p10 + carry; +			carry = 1000000000/p10 * tmp; +			if (k==a && !x[k]) { +				a = (a+1 & MASK); +				rp -= 9; +			} +		} +		if (carry) x[z++] = carry; +		rp += 9-rpm9; +	} + +	while (rp < 9*LD_B1B_DIG || (rp == 9*LD_B1B_DIG && x[0]<th[0])) { +		uint32_t carry = 0; +		e2 -= 29; +		for (k=(z-1 & MASK); ; k=(k-1 & MASK)) { +			uint64_t tmp = ((uint64_t)x[k] << 29) + carry; +			if (tmp > 1000000000) { +				carry = tmp / 1000000000; +				x[k] = tmp % 1000000000; +			} else { +				carry = 0; +				x[k] = tmp; +			} +			if (k==(z-1 & MASK) && k!=a && !x[k]) z = k; +			if (k==a) break; +		} +		if (carry) { +			rp += 9; +			if (a == z) { +				z = (z-1 & MASK); +				x[z-1 & MASK] |= x[z]; +			} +			a = (a-1 & MASK); +			x[a] = carry; +		} +	} + +	for (;;) { +		uint32_t carry = 0; +		int sh = 1; +		for (i=0; i<LD_B1B_DIG; i++) { +			k = (a+i & MASK); +			if (k == z || x[k] < th[i]) { +				i=LD_B1B_DIG; +				break; +			} +			if (x[a+i & MASK] > th[i]) break; +		} +		if (i==LD_B1B_DIG && rp==9*LD_B1B_DIG) break; +		/* FIXME: find a way to compute optimal sh */ +		if (rp > 9+9*LD_B1B_DIG) sh = 9; +		e2 += sh; +		for (i=0; (k=(a+i & MASK))!=z && i<LD_B1B_DIG+3; i++) { +			uint32_t tmp = x[k] & (1<<sh)-1; +			x[k] = (x[k]>>sh) + carry; +			carry = (1000000000>>sh) * tmp; +			if (k==a && !x[k]) { +				a = (a+1 & MASK); +				i--; +				rp -= 9; +			} +		} +		if (carry && k==z) { +			if ((z+1 & MASK) != a) { +				x[z] = carry; +				z = (z+1 & MASK); +			} else x[z-1 & MASK] |= 1; +		} +	} + +	for (y=i=0; i<LD_B1B_DIG; i++) { +		if ((a+i & MASK)==z) x[z=(z+1 & MASK)] = 0; +		y = 1000000000.0L * y + x[a+i & MASK]; +	} + +	y *= sign; + +	if (bits > LDBL_MANT_DIG+e2-emin) { +		bits = LDBL_MANT_DIG+e2-emin; +		if (bits<0) bits=0; +	} + +	if (bits < LDBL_MANT_DIG) { +		bias = copysignl(scalbn(1, 2*LDBL_MANT_DIG-bits-1), y); +		frac = fmodl(y, scalbn(1, LDBL_MANT_DIG-bits)); +		y -= frac; +		y += bias; +	} + +	if ((a+i & MASK) != z) { +		uint32_t t = x[a+i & MASK]; +		if (t < 500000000 && (t || (a+i+1 & MASK) != z)) +			frac += 0.25*sign; +		else if (t > 500000000) +			frac += 0.75*sign; +		else if (t == 500000000) { +			if ((a+i+1 & MASK) == z) +				frac += 0.5*sign; +			else +				frac += 0.75*sign; +		} +		if (LDBL_MANT_DIG-bits >= 2 && !fmodl(frac, 1)) +			frac++; +	} + +	y += frac; +	y -= bias; + +	y = scalbnl(y, e2); + +	if (!y) errno = ERANGE; + +	return y; +} + +static long double hexfloat(FILE *f, int bits, int emin, int sign, int pok) +{ +	uint32_t x = 0; +	long double y = 0; +	long double scale = 1; +	long double bias = 0; +	int gottail = 0, gotrad = 0, gotdig = 0; +	long long rp = 0; +	long long dc = 0; +	long long e2 = 0; +	int d; +	int c; + +	c = shgetc(f); + +	/* Skip leading zeros */ +	for (; c=='0'; c = shgetc(f)) gotdig = 1; + +	if (c=='.') { +		gotrad = 1; +		c = shgetc(f); +		/* Count zeros after the radix point before significand */ +		for (rp=0; c=='0'; c = shgetc(f), rp--) gotdig = 1; +	} + +	for (; c-'0'<10U || (c|32)-'a'<6U || c=='.'; c = shgetc(f)) { +		if (c=='.') { +			if (gotrad) break; +			rp = dc; +			gotrad = 1; +		} else { +			gotdig = 1; +			if (c > '9') d = (c|32)+10-'a'; +			else d = c-'0'; +			if (dc<8) { +				x = x*16 + d; +			} else if (dc < LDBL_MANT_DIG/4+1) { +				y += d*(scale/=16); +			} else if (d && !gottail) { +				y += 0.5*scale; +				gottail = 1; +			} +			dc++; +		} +	} +	if (!gotdig) { +		shunget(f); +		if (pok) { +			shunget(f); +			if (gotrad) shunget(f); +		} else { +			shlim(f, 0); +		} +		return 0; +	} +	if (!gotrad) rp = dc; +	while (dc<8) x *= 16, dc++; +	if ((c|32)=='p') { +		e2 = scanexp(f, pok); +		if (e2 == LLONG_MIN) { +			if (pok) { +				shunget(f); +			} else { +				shlim(f, 0); +				return 0; +			} +			e2 = 0; +		} +	} else { +		shunget(f); +	} +	e2 += 4*rp - 32; + +	if (!x) return sign * 0.0; +	if (e2 > -emin) { +		errno = ERANGE; +		return sign * LDBL_MAX * LDBL_MAX; +	} +	if (e2 < emin-2*LDBL_MANT_DIG) { +		errno = ERANGE; +		return sign * LDBL_MIN * LDBL_MIN; +	} + +	while (x < 0x80000000) { +		if (y>=0.5) { +			x += x + 1; +			y += y - 1; +		} else { +			x += x; +			y += y; +		} +		e2--; +	} + +	if (bits > 32+e2-emin) { +		bits = 32+e2-emin; +		if (bits<0) bits=0; +	} + +	if (bits < LDBL_MANT_DIG) +		bias = copysignl(scalbn(1, 32+LDBL_MANT_DIG-bits-1), sign); + +	if (bits<32 && y && !(x&1)) x++, y=0; + +	y = bias + sign*(long double)x + sign*y; +	y -= bias; + +	if (!y) errno = ERANGE; + +	return scalbnl(y, e2); +} + +long double __floatscan(FILE *f, int c, int prec, int pok) +{ +	int sign = 1; +	int i; +	int bits; +	int emin; + +	switch (prec) { +	case 0: +		bits = 24; +		emin = -149; +		break; +	case 1: +		bits = 53; +		emin = -1074; +		break; +	case 2: +		bits = LDBL_MANT_DIG; +		emin = -16445; +		break; +	default: +		return 0; +	} + +	if (c<0) c = shgetc(f); + +	if (c=='+' || c=='-') { +		sign -= 2*(c=='-'); +		c = shgetc(f); +	} + +	for (i=0; i<8 && (c|32)=="infinity"[i]; i++) +		if (i<7) c = shgetc(f); +	if (i==3 || i==8 || (i>3 && pok)) { +		if (i==3) shunget(f); +		if (pok) for (; i>3; i--) shunget(f); +		else shlim(f, 0); +		return sign * INFINITY; +	} +	if (!i) for (i=0; i<3 && (c|32)=="nan"[i]; i++) +		if (i<3) c = shgetc(f); +	if (i==3) { +		return NAN; +	} + +	if (i) { +		shunget(f); +		errno = EINVAL; +		shlim(f, 0); +		return 0; +	} + +	if (c=='0') { +		c = shgetc(f); +		if ((c|32) == 'x') +			return hexfloat(f, bits, emin, sign, pok); +		shunget(f); +		c = '0'; +	} + +	return decfloat(f, c, bits, emin, sign, pok); +} diff --git a/src/internal/floatscan.h b/src/internal/floatscan.h new file mode 100644 index 00000000..5595b81e --- /dev/null +++ b/src/internal/floatscan.h @@ -0,0 +1,8 @@ +#ifndef FLOATSCAN_H +#define FLOATSCAN_H + +#include <stdio.h> + +long double __floatscan(FILE *, int, int, int); + +#endif diff --git a/src/internal/shgetc.c b/src/internal/shgetc.c new file mode 100644 index 00000000..82e3a4fa --- /dev/null +++ b/src/internal/shgetc.c @@ -0,0 +1,24 @@ +#include "shgetc.h" + +void __shlim(FILE *f, off_t lim) +{ +	f->shlim = lim; +	f->shcnt = f->rend - f->rpos; +	if (lim && f->rend - f->rpos > lim) +		f->shend = f->rpos + lim; +	else +		f->shend = f->rend; +} + +int __shgetc(FILE *f) +{ +	int c; +	if (f->shcnt >= f->shlim) return EOF; +	c = __uflow(f); +	if (f->shlim && f->rend - f->rpos > f->shlim - f->shcnt - 1) +		f->shend = f->rpos + (f->shlim - f->shcnt - 1); +	else +		f->shend = f->rend; +	if (f->rend) f->shcnt += f->rend - f->buf; +	return c; +} diff --git a/src/internal/shgetc.h b/src/internal/shgetc.h new file mode 100644 index 00000000..3434cdaa --- /dev/null +++ b/src/internal/shgetc.h @@ -0,0 +1,25 @@ +#include "stdio_impl.h" + +void __shlim(FILE *, off_t); +int __shgetc(FILE *); + +static inline off_t shcnt(FILE *f) +{ +	return f->shcnt + (f->rpos - f->rend); +} + +static inline void shlim(FILE *f, off_t lim) +{ +	__shlim(f, lim); +} + +static inline int shgetc(FILE *f) +{ +	if (f->rpos < f->shend) return *f->rpos++; +	return __shgetc(f); +} + +static inline void shunget(FILE *f) +{ +	if (f->rend) f->rpos--; +} diff --git a/src/internal/stdio_impl.h b/src/internal/stdio_impl.h index c5f45eb1..5ec296f3 100644 --- a/src/internal/stdio_impl.h +++ b/src/internal/stdio_impl.h @@ -59,6 +59,8 @@ struct __FILE_s {  	off_t off;  	int (*flush)(FILE *);  	void *mustbezero_2; +	unsigned char *shend; +	off_t shlim, shcnt;  };  size_t __stdio_read(FILE *, unsigned char *, size_t); diff --git a/src/stdlib/strtod.c b/src/stdlib/strtod.c index 388058fe..ecfabdf1 100644 --- a/src/stdlib/strtod.c +++ b/src/stdlib/strtod.c @@ -1,6 +1,34 @@  #include <stdlib.h> +#include "shgetc.h" +#include "floatscan.h" +#include "stdio_impl.h" + +static long double strtox(const char *s, char **p, int prec) +{ +	char *t = (char *)s; +	while (isspace(*t)) t++; +	FILE f = { +		.buf = (void *)t, .rpos = (void *)t, +		.rend = (void *)-1, .lock = -1 +	}; +	shlim(&f, 0); +	long double y = __floatscan(&f, -1, prec, 1); +	off_t cnt = shcnt(&f); +	if (p) *p = cnt ? t + cnt : (char *)s; +	return y; +} + +float strtof(const char *s, char **p) +{ +	return strtox(s, p, 0); +}  double strtod(const char *s, char **p)  { -	return strtold(s, p); +	return strtox(s, p, 1); +} + +long double strtold(const char *s, char **p) +{ +	return strtox(s, p, 2);  } diff --git a/src/stdlib/strtof.c b/src/stdlib/strtof.c deleted file mode 100644 index 07b32df4..00000000 --- a/src/stdlib/strtof.c +++ /dev/null @@ -1,6 +0,0 @@ -#include <stdlib.h> - -float strtof(const char *s, char **p) -{ -	return strtold(s, p); -} diff --git a/src/stdlib/strtold.c b/src/stdlib/strtold.c deleted file mode 100644 index ec464c15..00000000 --- a/src/stdlib/strtold.c +++ /dev/null @@ -1,96 +0,0 @@ -#include <stdlib.h> -#include <errno.h> -#include <ctype.h> - -static int valid_exp(const unsigned char *s) -{ -	return isdigit(*s) || ((s[0]=='+'||s[0]=='-') && isdigit(s[1])); -} - -long double strtold(const char *s1, char **p) -{ -	const unsigned char *s = (void *)s1; -	long double x = 0; -	long double frac; -	int sign = 0; -	int nonzero = 0; -	int radix = '.'; -	long e; -	int saved_errno = errno; - -	if (!p) p = (char **)&s1; - -	/* Initial whitespace */ -	for (; isspace(*s); s++); - -	/* Optional sign */ -	if (*s == '-') sign = *s++; -	else if (*s == '+') s++; - -	/* Handle infinities and NaNs. */ -	if ((s[0]|32)=='i' && (s[1]|32)=='n' && (s[2]|32)=='f') { -		*p = (char *)s + 3; -		return sign ? -1.0/0.0 : 1.0/0.0; -	} else if ((s[0]|32)=='n' && (s[1]|32)=='a' && (s[2]|32)=='n') { -		*p = (char *)s + 3; -		return 0.0/0.0; -	} - -	/* Possible hex float */ -	if (s[0]=='0' && (s[1]|32)=='x') { -		/* Mantissa must be non-degenerate */ -		if (!isxdigit(s[2]) && (s[2]!=radix || !isxdigit(s[3]))) { -			/* Decimal float 0, 'x' extraneous */ -			*p = (char *)++s; -			return 0; -		} -		/* We have a real hex float */ -		s += 2; -		for (; isxdigit(*s); s++) { -			x = 16*x + (isdigit(*s)?*s-'0':(*s|32)-'a'+10); -			if (*s!='0') nonzero=1; -		} -		if (*s == radix) { -			frac = 1.0/16.0; -			for (s++; isxdigit(*s); s++) { -				x += frac * (isdigit(*s)?*s-'0':(*s|32)-'a'+10); -				frac *= 1.0/16.0; -				if (*s!='0') nonzero=1; -			} -		} -		if ((*s|32) == 'p' && valid_exp(s+1)) { -			e = strtol((void *)(s+1), (void *)&s, 10); -			for (; e>0; e--) x *= 2.0; -			for (; e<0; e++) x *= 0.5; -		} -		goto finish; -	} - -	/* Mantissa must be non-degenerate */ -	if (!isdigit(s[0]) && (s[0]!=radix || !isdigit(s[1]))) { -		*p = (char *)s1; -		return 0; -	} - -	for (; isdigit(*s); s++) { -		x = 10*x + *s-'0'; -		if (*s!='0') nonzero=1; -	} -	if (*s == radix) { -		frac = 10.0; -		for (s++; isdigit(*s); s++) { -			x += (*s-'0') / frac; -			frac *= 10.0; -			if (*s!='0') nonzero=1; -		} -	} -	if ((*s|32)=='e' && valid_exp(s+1)) { -		e = strtol((void *)++s, (void *)&s, 10); -		for (; e>0; e--) x *= 10.0; -		for (; e<0; e++) x /= 10.0; -	} -finish: -	errno = ((nonzero && !x) || !(1.0/x)) ? ERANGE : saved_errno; -	*p = (char*)s; -	return sign ? -x : x; -} | 
