1 /* 2 * mstolfp - convert an ascii string in milliseconds to an l_fp number 3 */ 4 #include <config.h> 5 #include <stdio.h> 6 #include <ctype.h> 7 8 #include "ntp_fp.h" 9 #include "ntp_stdlib.h" 10 11 int 12 mstolfp( 13 const char *str, 14 l_fp *lfp 15 ) 16 { 17 register const char *cp; 18 register char *bp; 19 register const char *cpdec; 20 char buf[100]; 21 22 /* 23 * We understand numbers of the form: 24 * 25 * [spaces][-][digits][.][digits][spaces|\n|\0] 26 * 27 * This is one enormous hack. Since I didn't feel like 28 * rewriting the decoding routine for milliseconds, what 29 * is essentially done here is to make a copy of the string 30 * with the decimal moved over three places so the seconds 31 * decoding routine can be used. 32 */ 33 bp = buf; 34 cp = str; 35 while (isspace((unsigned char)*cp)) 36 cp++; 37 38 if (*cp == '-') { 39 *bp++ = '-'; 40 cp++; 41 } 42 43 if (*cp != '.' && !isdigit((unsigned char)*cp)) 44 return 0; 45 46 47 /* 48 * Search forward for the decimal point or the end of the string. 49 */ 50 cpdec = cp; 51 while (isdigit((unsigned char)*cpdec)) 52 cpdec++; 53 54 /* 55 * Found something. If we have more than three digits copy the 56 * excess over, else insert a leading 0. 57 */ 58 if ((cpdec - cp) > 3) { 59 do { 60 *bp++ = (char)*cp++; 61 } while ((cpdec - cp) > 3); 62 } else { 63 *bp++ = '0'; 64 } 65 66 /* 67 * Stick the decimal in. If we've got less than three digits in 68 * front of the millisecond decimal we insert the appropriate number 69 * of zeros. 70 */ 71 *bp++ = '.'; 72 if ((cpdec - cp) < 3) { 73 size_t i = 3 - (cpdec - cp); 74 do { 75 *bp++ = '0'; 76 } while (--i > 0); 77 } 78 79 /* 80 * Copy the remainder up to the millisecond decimal. If cpdec 81 * is pointing at a decimal point, copy in the trailing number too. 82 */ 83 while (cp < cpdec) 84 *bp++ = (char)*cp++; 85 86 if (*cp == '.') { 87 cp++; 88 while (isdigit((unsigned char)*cp)) 89 *bp++ = (char)*cp++; 90 } 91 *bp = '\0'; 92 93 /* 94 * Check to make sure the string is properly terminated. If 95 * so, give the buffer to the decoding routine. 96 */ 97 if (*cp != '\0' && !isspace((unsigned char)*cp)) 98 return 0; 99 return atolfp(buf, lfp); 100 } 101