1 /* 2 * dofptoa - do the grunge work to convert an fp number to ascii 3 */ 4 #include <config.h> 5 #include <stdio.h> 6 7 #include "ntp_fp.h" 8 #include "lib_strbuf.h" 9 #include "ntp_string.h" 10 #include "ntp_stdlib.h" 11 12 char * 13 dofptoa( 14 u_fp fpv, 15 int neg, 16 short ndec, 17 int msec 18 ) 19 { 20 register u_char *cp, *cpend; 21 register u_long val; 22 register short dec; 23 u_char cbuf[12]; 24 u_char *cpdec; 25 char *buf; 26 char *bp; 27 28 /* 29 * Get a string buffer before starting 30 */ 31 LIB_GETBUF(buf); 32 33 /* 34 * Zero out the buffer 35 */ 36 ZERO(cbuf); 37 38 /* 39 * Set the pointers to point at the first 40 * decimal place. Get a local copy of the value. 41 */ 42 cp = cpend = &cbuf[5]; 43 val = fpv; 44 45 /* 46 * If we have to, decode the integral part 47 */ 48 if (!(val & 0xffff0000)) 49 cp--; 50 else { 51 register u_short sv = (u_short)(val >> 16); 52 register u_short tmp; 53 register u_short ten = 10; 54 55 do { 56 tmp = sv; 57 sv = (u_short) (sv/ten); 58 *(--cp) = (u_char)(tmp - ((sv<<3) + (sv<<1))); 59 } while (sv != 0); 60 } 61 62 /* 63 * Figure out how much of the fraction to do 64 */ 65 if (msec) { 66 dec = (short)(ndec + 3); 67 if (dec < 3) 68 dec = 3; 69 cpdec = &cbuf[8]; 70 } else { 71 dec = ndec; 72 cpdec = cpend; 73 } 74 75 if (dec > 6) 76 dec = 6; 77 78 if (dec > 0) { 79 do { 80 val &= 0xffff; 81 val = (val << 3) + (val << 1); 82 *cpend++ = (u_char)(val >> 16); 83 } while (--dec > 0); 84 } 85 86 if (val & 0x8000) { 87 register u_char *tp; 88 /* 89 * Round it. Ick. 90 */ 91 tp = cpend; 92 *(--tp) += 1; 93 while (*tp >= 10) { 94 *tp = 0; 95 *(--tp) += 1; 96 } 97 } 98 99 /* 100 * Remove leading zeroes if necessary 101 */ 102 while (cp < (cpdec -1) && *cp == 0) 103 cp++; 104 105 /* 106 * Copy it into the buffer, asciizing as we go. 107 */ 108 bp = buf; 109 if (neg) 110 *bp++ = '-'; 111 112 while (cp < cpend) { 113 if (cp == cpdec) 114 *bp++ = '.'; 115 *bp++ = (char)(*cp++ + '0'); 116 } 117 *bp = '\0'; 118 return buf; 119 } 120 121 122 char * 123 fptoa( 124 s_fp fpv, 125 short ndec 126 ) 127 { 128 u_fp plusfp; 129 int neg; 130 131 neg = (fpv < 0); 132 if (neg) { 133 plusfp = (u_fp)(-fpv); 134 } else { 135 plusfp = (u_fp)fpv; 136 } 137 138 return dofptoa(plusfp, neg, ndec, FALSE); 139 } 140 141 142 char * 143 fptoms( 144 s_fp fpv, 145 short ndec 146 ) 147 { 148 u_fp plusfp; 149 int neg; 150 151 neg = (fpv < 0); 152 if (neg) { 153 plusfp = (u_fp)(-fpv); 154 } else { 155 plusfp = (u_fp)fpv; 156 } 157 158 return dofptoa(plusfp, neg, ndec, TRUE); 159 } 160