Document Title

00457 {
00458   static char _blanks[] = "                    ";
00459   static char _zeroes[] = "00000000000000000000";
00460 
00461   /* counts output characters */
00462   int count = 0;
00463 
00464   /* format code */
00465   int fcode;
00466 
00467   /* field width and precision */
00468   int width, prec;
00469 
00470   /* number of padding zeroes required on the left and right */
00471   int lzero;
00472 
00473   /* length of prefix */
00474   int prefixlength;
00475 
00476   /* combined length of leading zeroes, trailing zeroes, and suffix */
00477   int otherlength;
00478 
00479   /* format flags */
00480 #define PADZERO         0x0001  /* padding zeroes requested via '0' */
00481 #define RZERO           0x0002  /* there will be trailing zeros in output */
00482 #define LZERO           0x0004  /* there will be leading zeroes in output */
00483 #define DOTSEEN         0x0008  /* dot appeared in format specification */
00484 #define LENGTH          0x0010  /* l */
00485   int flagword;
00486 
00487   /* maximum number of digits in printable number */
00488 #define MAXDIGS         22
00489 
00490   /* starting and ending points for value to be printed */
00491   char *bp, *p;
00492 
00493   /* work variables */
00494   int k, lradix, mradix;
00495 
00496   /* pointer to sign, "0x", "0X", or empty */
00497   char *prefix;
00498 
00499   /* values are developed in this buffer */
00500   static char buf[MAXDIGS*4], buf1[MAXDIGS*4];
00501 
00502   /* pointer to a translate table for digits of whatever radix */
00503   char *tab;
00504 
00505   /* value being converted, if integer */
00506   slargeint_t val;
00507 
00508   /* value being converted, if floating point */
00509   dfloat_t fval;
00510 
00511   for (;;)
00512     {
00513       int n;
00514 
00515       while ((fcode = *format) != '\0' && fcode != '%')
00516         {
00517           *obuf++ = fcode;
00518           format++;
00519           count++;
00520         }
00521 
00522       if (fcode == '\0')
00523         {
00524           /* end of format; terminate and return */
00525           *obuf = '\0';
00526           return obuf;
00527         }
00528 
00529 
00530       /* % has been found, the following switch is used to parse the format
00531          specification and to perform the operation specified by the format
00532          letter; the program repeatedly goes back to this switch until the
00533          format letter is encountered */
00534 
00535       width = prefixlength = otherlength = flagword = 0;
00536       format++;
00537 
00538     charswitch:
00539       switch (fcode = *format++)
00540         {
00541         case '0': /* means pad with leading zeros */
00542           flagword |= PADZERO;
00543         case '1':
00544         case '2':
00545         case '3':
00546         case '4':
00547         case '5':
00548         case '6':
00549         case '7':
00550         case '8':
00551         case '9':
00552           {
00553             int num = fcode - '0';
00554             while (isdigit(fcode = *format))
00555               {
00556                 num = num * 10 + fcode - '0';
00557                 format++;
00558               }
00559             if (flagword & DOTSEEN)
00560               prec = num;
00561             else
00562               width = num;
00563             goto charswitch;
00564           }
00565 
00566         case '.':
00567           flagword |= DOTSEEN;
00568           goto charswitch;
00569 
00570         case 'l':
00571           flagword |= LENGTH;
00572           goto charswitch;
00573 
00574         case 'n': /* host counter */
00575 #ifdef HOST_HAS_QWORD
00576           flagword |= LENGTH;
00577           /* fallthru */
00578 #else /* !HOST_HAS_QWORD */
00579           flagword |= DOTSEEN;
00580           if (!width)
00581             width = 12;
00582           prec = 0;
00583           goto process_float;
00584 #endif /* HOST_HAS_QWORD */
00585           
00586         case 'd':
00587           /* fetch the argument to be printed */
00588           if (flagword & LENGTH)
00589             val = va_arg(v, slargeint_t);
00590           else
00591             val = (slargeint_t)va_arg(v, sword_t);
00592 
00593           /* set buffer pointer to last digit */
00594           p = bp = buf + MAXDIGS;
00595 
00596           /* If signed conversion, make sign */
00597           if (val < 0)
00598             {
00599               prefix = "-";
00600               prefixlength = 1;
00601               /* negate, checking in advance for possible overflow */
00602               if (val != (slargeint_t)HIBITL)
00603                 val = -val;
00604               else
00605                 {
00606                   /* number is -HIBITL; convert last digit and get pos num */
00607                   *--bp = _lowdigit(&val);
00608                 }
00609             }
00610 
00611         decimal:
00612           {
00613             slargeint_t qval = val;
00614 
00615             if (qval <= 9)
00616               *--bp = (int)qval + '0';
00617             else
00618               {
00619                 do {
00620                   n = (int)qval;
00621                   qval /= 10;
00622                   *--bp = n - (int)qval * 10 + '0';
00623                 }
00624                 while (qval > 9);
00625                 *--bp = (int)qval + '0';
00626               }
00627           }
00628           break;
00629 
00630         case 'u':
00631           /* fetch the argument to be printed */
00632           if (flagword & LENGTH)
00633             val = va_arg(v, largeint_t);
00634           else
00635             val = (largeint_t)va_arg(v, word_t);
00636 
00637           /* set buffer pointer to last digit */
00638           p = bp = buf + MAXDIGS;
00639 
00640           if (val & HIBITL)
00641             *--bp = _lowdigit(&val);
00642           goto decimal;
00643 
00644         case 'o':
00645           mradix = 7;
00646           lradix = 2;
00647           goto fixed;
00648 
00649         case 'p': /* target address */
00650           if (sizeof(md_addr_t) > 4)
00651             flagword |= LENGTH;
00652           /* fallthru */
00653 
00654         case 'X':
00655         case 'x':
00656           mradix = 15;
00657           lradix = 3;
00658 
00659         fixed:
00660           /* fetch the argument to be printed */
00661           if (flagword & LENGTH)
00662             val = va_arg(v, largeint_t);
00663           else
00664             val = (largeint_t)va_arg(v, word_t);
00665 
00666           /* set translate table for digits */
00667           tab = (fcode == 'X') ? "0123456789ABCDEF" : "0123456789abcdef";
00668 
00669           /* develop the digits of the value */
00670           p = bp = buf + MAXDIGS;
00671 
00672           {
00673             slargeint_t qval = val;
00674 
00675             if (qval == 0)
00676               {
00677                 otherlength = lzero = 1;
00678                 flagword |= LZERO;
00679               }
00680             else
00681               do {
00682                 *--bp = tab[qval & mradix];
00683                 qval = ((qval >> 1) & ~HIBITL) >> lradix;
00684               } while (qval != 0);
00685           }
00686           break;
00687 
00688 #ifndef HOST_HAS_QWORD
00689         process_float:
00690 #endif /* !HOST_HAS_QWORD */
00691 
00692         case 'f':
00693           if (flagword & DOTSEEN)
00694             sprintf(buf1, "%%%d.%df", width, prec);
00695           else if (width)
00696             sprintf(buf1, "%%%df", width);
00697           else
00698             sprintf(buf1, "%%f");
00699 
00700           /* fetch the argument to be printed */
00701           fval = va_arg(v, dfloat_t);
00702 
00703           /* print floating point value */
00704           sprintf(buf, buf1, fval);
00705           bp = buf;
00706           p = bp + strlen(bp);
00707           break;
00708 
00709         case 's':
00710           bp = va_arg(v, char *);
00711           if (bp == NULL)
00712             bp = "(null)";
00713           p = bp + strlen(bp);
00714           break;
00715 
00716         case '%':
00717           buf[0] = fcode;
00718           goto c_merge;
00719 
00720         case 'c':
00721           buf[0] = va_arg(v, int);
00722         c_merge:
00723           p = (bp = &buf[0]) + 1;
00724           break;
00725 
00726         default:
00727           /* this is technically an error; what we do is to back up the format
00728              pointer to the offending char and continue with the format scan */
00729           format--;
00730           continue;
00731         }
00732 
00733       /* calculate number of padding blanks */
00734       k = (n = p - bp) + prefixlength + otherlength;
00735       if (width <= k)
00736         count += k;
00737       else
00738         {
00739           count += width;
00740 
00741           /* set up for padding zeroes if requested; otherwise emit padding
00742              blanks unless output is to be left-justified */
00743           if (flagword & PADZERO)
00744             {
00745               if (!(flagword & LZERO))
00746                 {
00747                   flagword |= LZERO;
00748                   lzero = width - k;
00749                 }
00750               else
00751                 lzero += width - k;
00752 
00753               /* cancel padding blanks */
00754               k = width;
00755             }
00756           else
00757             {
00758               /* blanks on left if required */
00759               PAD(_blanks, width - k);
00760             }
00761         }
00762 
00763       /* prefix, if any */
00764       if (prefixlength != 0)
00765         {
00766           PUT(prefix, prefixlength);
00767         }
00768 
00769       /* zeroes on the left */
00770       if (flagword & LZERO)
00771         {
00772           PAD(_zeroes, lzero);
00773         }
00774 
00775       /* the value itself */
00776       if (n > 0)
00777         {
00778           PUT(bp, n);
00779         }
00780     }
00781 }
misc.h File Reference

Defines

Functions

Variables

Define Documentation

Function Documentation

Variable Documentation


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