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-rw-r--r--src/internal/floatscan.c438
-rw-r--r--src/internal/floatscan.h8
-rw-r--r--src/stdlib/strtod.c11
-rw-r--r--src/stdlib/strtof.c11
-rw-r--r--src/stdlib/strtold.c103
5 files changed, 477 insertions, 94 deletions
diff --git a/src/internal/floatscan.c b/src/internal/floatscan.c
new file mode 100644
index 00000000..15ad5e12
--- /dev/null
+++ b/src/internal/floatscan.c
@@ -0,0 +1,438 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <math.h>
+#include <float.h>
+#include <limits.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)
+
+
+#if 1
+#include "stdio_impl.h"
+#undef ungetc
+#define ungetc(c,f) ((f)->rpos--,(c))
+#undef getc
+#define getc getc_unlocked
+#endif
+
+
+static long long scanexp(FILE *f, off_t *pcnt)
+{
+ int c;
+ int x;
+ long long y;
+ int neg = 0;
+
+ *pcnt += (c=getc(f))>=0;
+ if (c=='+' || c=='-') {
+ neg = (c=='-');
+ *pcnt += (c=getc(f))>=0;
+ if (c-'0'>=10U) {
+ if (c>=0) {
+ ungetc(c, f);
+ --*pcnt;
+ }
+ return LLONG_MIN;
+ }
+ }
+ for (x=0; c-'0'<10U && x<INT_MAX/10; *pcnt += (c=getc(f))>=0)
+ x = 10*x + c-'0';
+ for (y=x; c-'0'<10U && x<LLONG_MAX/10; *pcnt += (c=getc(f))>=0)
+ y = 10*y + c-'0';
+ for (; c-'0'<10U; *pcnt += (c=getc(f))>=0);
+ if (c>=0) {
+ ungetc(c, f);
+ --*pcnt;
+ }
+ return neg ? -y : y;
+}
+
+
+static long double decfloat(FILE *f, int c, int bits, int emin, int sign, int pok, off_t *pcnt)
+{
+ uint32_t x[KMAX];
+ static const uint32_t th[] = { LD_B1B_MAX };
+ int i, j, k, a, z;
+ long long lrp=-1, dc=0;
+ int gotdig = 0;
+ int rp;
+ int e10=0;
+ int e2;
+ long double y;
+ long double frac=0;
+ long double bias=0;
+
+ j=0;
+ k=0;
+
+ if (c<0) *pcnt += (c=getc(f))>=0;
+
+ /* Don't let leading zeros consume buffer space */
+ for (; c=='0'; *pcnt += (c=getc(f))>=0) gotdig=1;
+
+ x[0] = 0;
+ for (; c-'0'<10U || c=='.'; *pcnt += (c=getc(f))>=0) {
+ if (c == '.') {
+ if (lrp!=-1) break;
+ lrp = dc;
+ } else if (k < KMAX) {
+ 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++;
+ x[KMAX-1] |= c-'0';
+ }
+ }
+ if (lrp==-1) lrp=dc;
+
+ if (gotdig && (c|32)=='e') {
+ e10 = scanexp(f, pcnt);
+ if (e10 == LLONG_MIN) {
+ if (!pok) {
+ *pcnt = 0;
+ return 0;
+ }
+ e10 = 0;
+ }
+ lrp += e10;
+ } else if (c>=0) {
+ ungetc(c, f);
+ --*pcnt;
+ }
+ if (!gotdig) {
+ *pcnt = 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)
+ return sign * LDBL_MAX * LDBL_MAX;
+ if (lrp < emin-2*LDBL_MANT_DIG)
+ 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;
+
+ while (rp < 18+9*LD_B1B_DIG) {
+ 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;
+ }
+ }
+
+ if (rp % 9) {
+ static const int p10s[] = {
+ 100000000, 10000000, 1000000, 100000,
+ 10000, 1000, 100, 10
+ };
+ int rpm9 = rp % 9;
+ int p10 = p10s[rpm9-1];
+ uint32_t carry = 0;
+ for (k=a; k!=z; k=(k+1 & MASK)) {
+ 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) {
+ if ((z+1 & MASK) != a) {
+ x[z] = carry;
+ z = (z+1 & MASK);
+ } else x[z-1 & MASK] |= 1;
+ }
+ rp += 9-rpm9;
+ }
+
+ 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 (k=a; k!=z; k=(k+1 & MASK)) {
+ 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);
+ rp -= 9;
+ }
+ }
+ if (carry) {
+ 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 && (a+i & MASK)!=z; i++)
+ 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);
+
+ return y;
+}
+
+static long double hexfloat(FILE *f, int c, int bits, int emin, int sign, int pok, off_t *pcnt)
+{
+ 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;
+
+ if (c<0) *pcnt += (c=getc(f))>=0;
+
+ /* Skip leading zeros */
+ for (; c=='0'; *pcnt += (c=getc(f))>=0) gotdig = 1;
+
+ if (c=='.') {
+ gotrad = 1;
+ *pcnt += (c=getc(f))>=0;
+ /* Count zeros after the radix point before significand */
+ for (rp=0; c=='0'; *pcnt += (c=getc(f))>=0, rp--) gotdig = 1;
+ }
+
+ for (; c-'0'<10U || (c|32)-'a'<6U || c=='.'; *pcnt += (c=getc(f))>=0) {
+ 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) {
+ if (c>=0) {
+ ungetc(c, f);
+ --*pcnt;
+ }
+ if (pok) *pcnt -= 1+gotrad; /* uncount the rp, x of 0x */
+ else *pcnt = 0;
+ return 0;
+ }
+ if (!gotrad) rp = dc;
+ while (dc<8) x *= 16, dc++;
+ if ((c|32)=='p') {
+ e2 = scanexp(f, pcnt);
+ if (e2 == LLONG_MIN) {
+ if (!pok) {
+ *pcnt = 0;
+ return 0;
+ }
+ e2 = 0;
+ }
+ }
+ e2 += 4*rp - 32;
+
+ if (!x) return sign * 0.0;
+ if (e2 > -emin) return sign * LDBL_MAX * LDBL_MAX;
+ if (e2 < emin-2*LDBL_MANT_DIG) 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;
+
+ return scalbnl(y, e2);
+}
+
+long double __floatscan(FILE *f, int c, int prec, int pok, off_t *pcnt)
+{
+ int sign = 1;
+ int i;
+ int bits;
+ int emin;
+
+ *pcnt = 0;
+
+ 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) *pcnt += (c=getc(f))>=0;
+
+ if (c=='+' || c=='-') {
+ sign -= 2*(c=='-');
+ *pcnt += (c=getc(f))>=0;
+ }
+
+ for (i=0; i<8 && (c|32)=="infinity"[i]; i++)
+ if (i<7) c = getc(f);
+ if (i==3 || i==8 || (i>3 && pok)) {
+ if (i==3 && c>=0) ungetc(c, f);
+ if (i==8) *pcnt += 7;
+ else *pcnt += 2;
+ return sign * INFINITY;
+ }
+ if (!i) for (i=0; i<3 && (c|32)=="nan"[i]; i++)
+ if (i<3) c = getc(f);
+ if (i==3) {
+ *pcnt += 2;
+ return sign>0 ? NAN : -NAN;
+ }
+
+ if (i) {
+ if (c>=0) ungetc(c, f);
+ *pcnt = 0;
+ return 0;
+ }
+
+ if (c=='0') {
+ *pcnt += (c=getc(f))>=0;
+ if ((c|32) == 'x')
+ return hexfloat(f, -1, bits, emin, sign, pok, pcnt);
+ if (c>=0) {
+ ungetc(c, f);
+ --*pcnt;
+ }
+ c = '0';
+ }
+
+ return decfloat(f, c, bits, emin, sign, pok, pcnt);
+}
diff --git a/src/internal/floatscan.h b/src/internal/floatscan.h
new file mode 100644
index 00000000..5ea74cc9
--- /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, off_t *);
+
+#endif
diff --git a/src/stdlib/strtod.c b/src/stdlib/strtod.c
index 388058fe..98b992a1 100644
--- a/src/stdlib/strtod.c
+++ b/src/stdlib/strtod.c
@@ -1,6 +1,15 @@
#include <stdlib.h>
+#include "floatscan.h"
+#include "stdio_impl.h"
double strtod(const char *s, char **p)
{
- return strtold(s, p);
+ FILE f = {
+ .buf = (void *)s, .rpos = (void *)s,
+ .rend = (void *)-1, .lock = -1
+ };
+ off_t cnt;
+ double y = __floatscan(&f, -1, 1, 1, &cnt);
+ if (p) *p = (char *)s + cnt;
+ return y;
}
diff --git a/src/stdlib/strtof.c b/src/stdlib/strtof.c
index 07b32df4..2dc349a9 100644
--- a/src/stdlib/strtof.c
+++ b/src/stdlib/strtof.c
@@ -1,6 +1,15 @@
#include <stdlib.h>
+#include "floatscan.h"
+#include "stdio_impl.h"
float strtof(const char *s, char **p)
{
- return strtold(s, p);
+ FILE f = {
+ .buf = (void *)s, .rpos = (void *)s,
+ .rend = (void *)-1, .lock = -1
+ };
+ off_t cnt;
+ float y = __floatscan(&f, -1, 0, 1, &cnt);
+ if (p) *p = (char *)s + cnt;
+ return y;
}
diff --git a/src/stdlib/strtold.c b/src/stdlib/strtold.c
index ec464c15..40ecc122 100644
--- a/src/stdlib/strtold.c
+++ b/src/stdlib/strtold.c
@@ -1,96 +1,15 @@
#include <stdlib.h>
-#include <errno.h>
-#include <ctype.h>
+#include "floatscan.h"
+#include "stdio_impl.h"
-static int valid_exp(const unsigned char *s)
+long double strtold(const char *s, char **p)
{
- 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;
+ FILE f = {
+ .buf = (void *)s, .rpos = (void *)s,
+ .rend = (void *)-1, .lock = -1
+ };
+ off_t cnt;
+ long double y = __floatscan(&f, -1, 2, 1, &cnt);
+ if (p) *p = (char *)s + cnt;
+ return y;
}