Revert removal of atof.c and strtod.c in r71341. We're not quite

ready for this yet---this removal should happen as part of the
py3k-short-float-repr merge.

diff --git a/Python/atof.c b/Python/atof.c
new file mode 100644 (file)
index 0000000..8fbde38
--- /dev/null
+++ b/Python/atof.c
@@ -0,0 +1,50 @@
+
+/* Just in case you haven't got an atof() around...
+   This one doesn't check for bad syntax or overflow,
+   and is slow and inaccurate.
+   But it's good enough for the occasional string literal... */
+
+#include "pyconfig.h"
+
+#include <ctype.h>
+
+double atof(char *s)
+{
+       double a = 0.0;
+       int e = 0;
+       int c;
+       while ((c = *s++) != '\0' && isdigit(c)) {
+               a = a*10.0 + (c - '0');
+       }
+       if (c == '.') {
+               while ((c = *s++) != '\0' && isdigit(c)) {
+                       a = a*10.0 + (c - '0');
+                       e = e-1;
+               }
+       }
+       if (c == 'e' || c == 'E') {
+               int sign = 1;
+               int i = 0;
+               c = *s++;
+               if (c == '+')
+                       c = *s++;
+               else if (c == '-') {
+                       c = *s++;
+                       sign = -1;
+               }
+               while (isdigit(c)) {
+                       i = i*10 + (c - '0');
+                       c = *s++;
+               }
+               e += i*sign;
+       }
+       while (e > 0) {
+               a *= 10.0;
+               e--;
+       }
+       while (e < 0) {
+               a *= 0.1;
+               e++;
+       }
+       return a;
+}

diff --git a/Python/strtod.c b/Python/strtod.c
new file mode 100644 (file)
index 0000000..a248460
--- /dev/null
+++ b/Python/strtod.c
@@ -0,0 +1,156 @@
+#include "pyconfig.h"
+
+/* comp.sources.misc strtod(), as posted in comp.lang.tcl,
+   with bugfix for "123000.0" and acceptance of space after 'e' sign nuked.
+
+   ************************************************************
+   * YOU MUST EDIT THE MACHINE-DEPENDENT DEFINITIONS BELOW!!! *
+   ************************************************************
+*/
+
+/*  File   : stdtod.c (Modified version of str2dbl.c)
+    Author : Richard A. O'Keefe @ Quintus Computer Systems, Inc.
+    Updated: Tuesday August 2nd, 1988
+    Defines: double strtod (char *str, char**ptr)
+*/
+
+/*  This is an implementation of the strtod() function described in the 
+    System V manuals, with a different name to avoid linker problems.
+    All that str2dbl() does itself is check that the argument is well-formed
+    and is in range.  It leaves the work of conversion to atof(), which is
+    assumed to exist and deliver correct results (if they can be represented).
+
+    There are two reasons why this should be provided to the net:
+    (a) some UNIX systems do not yet have strtod(), or do not have it
+        available in the BSD "universe" (but they do have atof()).
+    (b) some of the UNIX systems that *do* have it get it wrong.
+       (some crash with large arguments, some assign the wrong *ptr value).
+    There is a reason why *we* are providing it: we need a correct version
+    of strtod(), and if we give this one away maybe someone will look for
+    mistakes in it and fix them for us (:-).
+*/
+    
+/*  The following constants are machine-specific.  MD{MIN,MAX}EXPT are
+    integers and MD{MIN,MAX}FRAC are strings such that
+       0.${MDMAXFRAC}e${MDMAXEXPT} is the largest representable double,
+       0.${MDMINFRAC}e${MDMINEXPT} is the smallest representable +ve double
+    MD{MIN,MAX}FRAC must not have any trailing zeros.
+    The values here are for IEEE-754 64-bit floats.
+    It is not perfectly clear to me whether an IEEE infinity should be
+    returned for overflow, nor what a portable way of writing one is,
+    so HUGE is just 0.MAXFRAC*10**MAXEXPT (this seems still to be the
+    UNIX convention).
+
+    I do know about <values.h>, but the whole point of this file is that
+    we can't always trust that stuff to be there or to be correct.
+*/
+static int     MDMINEXPT       = -323;
+static char    MDMINFRAC[]     = "494065645841246544";
+static double  ZERO            = 0.0;
+
+static int     MDMAXEXPT       = 309;
+static char    MDMAXFRAC[]     = "17976931348623157";
+static double  HUGE            = 1.7976931348623157e308;
+
+extern double  atof(const char *);             /* Only called when result known to be ok */
+
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+extern int     errno;
+
+double strtod(char *str, char **ptr)
+{
+       int sign, scale, dotseen;
+       int esign, expt;
+       char *save;
+       register char *sp, *dp;
+       register int c;
+       char *buforg, *buflim;
+       char buffer[64];                /* 45-digit significant + */
+                                       /* 13-digit exponent */
+       sp = str;
+       while (*sp == ' ') sp++;
+       sign = 1;
+       if (*sp == '-') sign -= 2, sp++;
+       dotseen = 0, scale = 0;
+       dp = buffer;    
+       *dp++ = '0'; *dp++ = '.';
+       buforg = dp, buflim = buffer+48;
+       for (save = sp; c = *sp; sp++)
+           if (c == '.') {
+               if (dotseen) break;
+               dotseen++;
+           } else
+           if ((unsigned)(c-'0') > (unsigned)('9'-'0')) {
+               break;
+           } else
+           if (c == '0') {
+               if (dp != buforg) {
+                   /* This is not the first digit, so we want to keep it */
+                   if (dp < buflim) *dp++ = c;
+                   if (!dotseen) scale++;
+               } else {
+                   /* No non-zero digits seen yet */
+                   /* If a . has been seen, scale must be adjusted */
+                   if (dotseen) scale--;
+               }
+           } else {
+               /* This is a nonzero digit, so we want to keep it */
+               if (dp < buflim) *dp++ = c;
+               /* If it precedes a ., scale must be adjusted */
+               if (!dotseen) scale++;
+           }
+       if (sp == save) {
+           if (ptr) *ptr = str;
+           errno = EDOM;               /* what should this be? */
+           return ZERO;
+       }
+       
+       while (dp > buforg && dp[-1] == '0') --dp;
+       if (dp == buforg) *dp++ = '0';
+       *dp = '\0';
+       /*  Now the contents of buffer are
+           +--+--------+-+--------+
+           |0.|fraction|\|leftover|
+           +--+--------+-+--------+
+                        ^dp points here
+           where fraction begins with 0 iff it is "0", and has at most
+           45 digits in it, and leftover is at least 16 characters.
+       */
+       save = sp, expt = 0, esign = 1;
+       do {
+           c = *sp++;
+           if (c != 'e' && c != 'E') break;
+           c = *sp++;
+           if (c == '-') esign -= 2, c = *sp++; else
+           if (c == '+' /* || c == ' ' */ ) c = *sp++;
+           if ((unsigned)(c-'0') > (unsigned)('9'-'0')) break;
+           while (c == '0') c = *sp++;
+           for (; (unsigned)(c-'0') <= (unsigned)('9'-'0'); c = *sp++)
+               expt = expt*10 + c-'0';     
+           if (esign < 0) expt = -expt;
+           save = sp-1;
+       } while (0);
+       if (ptr) *ptr = save;
+       expt += scale;
+       /*  Now the number is sign*0.fraction*10**expt  */
+       errno = ERANGE;
+       if (expt > MDMAXEXPT) {
+           return HUGE*sign;
+       } else
+       if (expt == MDMAXEXPT) {
+           if (strcmp(buforg, MDMAXFRAC) > 0) return HUGE*sign;
+       } else
+       if (expt < MDMINEXPT) {
+           return ZERO*sign;
+       } else
+       if (expt == MDMINEXPT) {
+           if (strcmp(buforg, MDMINFRAC) < 0) return ZERO*sign;
+       }
+       /*  We have now established that the number can be  */
+       /*  represented without overflow or underflow  */
+       (void) sprintf(dp, "E%d", expt);
+       errno = 0;
+       return atof(buffer)*sign;
+}