Import Dev86src-0.16.17.tar.gzv0.16.17

2 files changed, 124 insertions, 2 deletions

diff --git a/libc/i386fp/Makefile b/libc/i386fp/Makefile
index 298ca18..e26ce21 100644
--- a/libc/i386fp/Makefile
+++ b/libc/i386fp/Makefile
@@ -9,12 +9,12 @@ FPSRC		=fadd.x fcomp.x fdiv.x fmul.x fbsr.x \
 		fperr.c fperror.x fptoi.x fpushd.x fpulld.x \
 		fpushi.x fpushf.x fpullf.x frexp.x ftst.x \
 		gcclib.x \
-		fabs.x ldexp.x modf.c \
+		fabs.x ldexp.x ecvt.c \
 		fperr.h fplib.h
 FPOBJ		=fadd.o fcomp.o fdiv.o fmul.o fpbsr.o \
 		fperr.o fperror.o fptoi.o fpushd.o fpulld.o \
 		fpushi.o fpushf.o fpullf.o frexp.o ftst.o \
-		fabs.o ldexp.o modf.o
+		fabs.o ldexp.o ecvt.o
 LIB		=.
 
 CFLAGS=$(ARCH) $(CCFLAGS) $(DEFS)
diff --git a/libc/i386fp/ecvt.c b/libc/i386fp/ecvt.c
new file mode 100644
index 0000000..6e0cef1
--- /dev/null
+++ b/libc/i386fp/ecvt.c
@@ -0,0 +1,122 @@
+
+#define DIGMAX	30		/* max # of digits in string */
+#define DIGPREC	17		/* max # of significant digits */
+#define ECVT	0
+#define FCVT	1
+static char digstr[DIGMAX + 1 + 1];    /* +1 for end of string         */
+
+    /* +1 in case rounding adds     */
+    /* another digit                */
+static double negtab[] =
+    { 1e-256, 1e-128, 1e-64, 1e-32, 1e-16, 1e-8, 1e-4, 1e-2, 1e-1, 1.0 };
+static double postab[] =
+    { 1e+256, 1e+128, 1e+64, 1e+32, 1e+16, 1e+8, 1e+4, 1e+2, 1e+1 };
+
+static char *_cvt();
+
+/*************************
+ * Convert double val to a string of
+ * decimal digits.
+ *	ndig = # of digits in resulting string
+ * Returns:
+ *	*pdecpt = position of decimal point from left of first digit
+ *	*psign  = nonzero if value was negative
+ */
+char *
+ecvt(val, ndig, pdecpt, psign)
+double val;
+int   ndig, *pdecpt, *psign;
+
+{
+   return _cvt(ECVT, val, ndig, pdecpt, psign);
+}
+
+char *
+fcvt(val, nfrac, pdecpt, psign)
+double val;
+int   nfrac, *pdecpt, *psign;
+
+{
+   return _cvt(FCVT, val, nfrac, pdecpt, psign);
+}
+
+static char *
+_cvt(cnvflag, val, ndig, pdecpt, psign)
+double val;
+int   ndig, *pdecpt, *psign;
+
+{
+   int   decpt, pow, i;
+   char *p;
+   *psign = (val < 0) ? ((val = -val), 1) : 0;
+   ndig = (ndig < 0) ? 0 : (ndig < DIGMAX) ? ndig : DIGMAX;
+   if (val == 0) {
+      for (p = &digstr[0]; p < &digstr[ndig]; p++)
+	 *p = '0';
+      decpt = 0;
+   } else {
+      /* Adjust things so that 1 <= val < 10  */
+      /* in these loops if val == MAXDOUBLE)  */
+      decpt = 1;
+      pow = 256;
+      i = 0;
+      while (val < 1) {
+	 while (val < negtab[i + 1]) {
+	    val /= negtab[i];
+	    decpt -= pow;
+	 }
+	 pow >>= 1;
+	 i++;
+      }
+      pow = 256;
+      i = 0;
+      while (val >= 10) {
+	 while (val >= postab[i]) {
+	    val /= postab[i];
+	    decpt += pow;
+	 }
+	 pow >>= 1;
+	 i++;
+      }
+      if (cnvflag == FCVT) {
+	 ndig += decpt;
+	 ndig = (ndig < 0) ? 0 : (ndig < DIGMAX) ? ndig : DIGMAX;
+      }
+
+      /* Pick off digits 1 by 1 and stuff into digstr[]       */
+      /* Do 1 extra digit for rounding purposes               */
+      for (p = &digstr[0]; p <= &digstr[ndig]; p++) {
+	 int   n;
+
+	 /* 'twould be silly to have zillions of digits  */
+	 /* when only DIGPREC are significant            */
+	 if (p >= &digstr[DIGPREC])
+	    *p = '0';
+
+	 else {
+	    n = val;
+	    *p = n + '0';
+	    val = (val - n) * 10;	/* get next digit */
+	 }
+      }
+      if (*--p >= '5') {	/* if we need to round              */
+	 while (1) {
+	    if (p == &digstr[0]) {	/* if at start      */
+	       ndig += cnvflag;
+	       decpt++;		/* shift dec pnt */
+	       digstr[0] = '1';	/* "100000..." */
+	       break;
+	    }
+	    *p = '0';
+	    --p;
+	    if (*p != '9') {
+	       (*p)++;
+	       break;
+	    }
+	 }			/* while */
+      }				/* if */
+   }				/* else */
+   *pdecpt = decpt;
+   digstr[ndig] = 0;		/* terminate string             */
+   return &digstr[0];
+}