1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #if defined(LIBC_SCCS) && !defined(lint) 19 static char sccsid[] = "@(#)strftime.c 5.4 (Berkeley) 03/14/89"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 #include <sys/types.h> 23 #include <sys/time.h> 24 #include <tzfile.h> 25 26 static char *afmt[] = { 27 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", 28 }; 29 static char *Afmt[] = { 30 "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", 31 "Saturday", 32 }; 33 static char *bfmt[] = { 34 "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", 35 "Oct", "Nov", "Dec", 36 }; 37 static char *Bfmt[] = { 38 "January", "February", "March", "April", "May", "June", "July", 39 "August", "September", "October", "November", "December", 40 }; 41 42 static size_t gsize; 43 static char *pt; 44 45 size_t 46 strftime(s, maxsize, format, t) 47 char *s; 48 char *format; 49 size_t maxsize; 50 struct tm *t; 51 { 52 size_t _fmt(); 53 54 pt = s; 55 if ((gsize = maxsize) < 1) 56 return(0); 57 if (_fmt(format, t)) { 58 *pt = '\0'; 59 return(maxsize - gsize); 60 } 61 return(0); 62 } 63 64 static size_t 65 _fmt(format, t) 66 register char *format; 67 struct tm *t; 68 { 69 for (; *format; ++format) { 70 if (*format == '%') 71 switch(*++format) { 72 case '\0': 73 --format; 74 break; 75 case 'A': 76 if (t->tm_wday < 0 || t->tm_wday > 6) 77 return(0); 78 if (!_add(Afmt[t->tm_wday])) 79 return(0); 80 continue; 81 case 'a': 82 if (t->tm_wday < 0 || t->tm_wday > 6) 83 return(0); 84 if (!_add(afmt[t->tm_wday])) 85 return(0); 86 continue; 87 case 'B': 88 if (t->tm_mon < 0 || t->tm_mon > 11) 89 return(0); 90 if (!_add(Bfmt[t->tm_mon])) 91 return(0); 92 continue; 93 case 'b': 94 case 'h': 95 if (t->tm_mon < 0 || t->tm_mon > 11) 96 return(0); 97 if (!_add(bfmt[t->tm_mon])) 98 return(0); 99 continue; 100 case 'c': 101 if (!_fmt("%a %b %d %X %Z %Y", t)) 102 return(0); 103 continue; 104 case 'D': 105 if (!_fmt("%m/%d/%y", t)) 106 return(0); 107 continue; 108 case 'd': 109 if (!_conv(t->tm_mday, 2)) 110 return(0); 111 continue; 112 case 'H': 113 if (!_conv(t->tm_hour, 2)) 114 return(0); 115 continue; 116 case 'I': 117 if (!_conv(t->tm_hour % 12 ? 118 t->tm_hour % 12 : 12, 2)) 119 return(0); 120 continue; 121 case 'j': 122 if (!_conv(t->tm_yday + 1, 3)) 123 return(0); 124 continue; 125 case 'M': 126 if (!_conv(t->tm_min, 2)) 127 return(0); 128 continue; 129 case 'm': 130 if (!_conv(t->tm_mon + 1, 2)) 131 return(0); 132 continue; 133 case 'n': 134 if (!_add("\n")) 135 return(0); 136 continue; 137 case 'p': 138 if (!_add(t->tm_hour >= 12 ? "PM" : "AM")) 139 return(0); 140 continue; 141 case 'R': 142 if (!_fmt("%H:%M", t)) 143 return(0); 144 continue; 145 case 'r': 146 if (!_fmt("%I:%M:%S %p", t)) 147 return(0); 148 continue; 149 case 'S': 150 if (!_conv(t->tm_sec, 2)) 151 return(0); 152 continue; 153 case 'T': 154 case 'X': 155 if (!_fmt("%H:%M:%S", t)) 156 return(0); 157 continue; 158 case 't': 159 if (!_add("\t")) 160 return(0); 161 continue; 162 case 'U': 163 if (!_conv((t->tm_yday + 7 - t->tm_wday) / 7, 164 2)) 165 return(0); 166 continue; 167 case 'W': 168 if (!_conv((t->tm_yday + 7 - 169 (t->tm_wday ? (t->tm_wday - 1) : 6)) 170 / 7, 2)) 171 return(0); 172 continue; 173 case 'w': 174 if (!_conv(t->tm_wday, 1)) 175 return(0); 176 continue; 177 case 'x': 178 if (!_fmt("%a %b %d %Y", t)) 179 return(0); 180 continue; 181 case 'y': 182 if (!_conv((t->tm_year + TM_YEAR_BASE) 183 % 100, 2)) 184 return(0); 185 continue; 186 case 'Y': 187 if (!_conv(t->tm_year + TM_YEAR_BASE, 4)) 188 return(0); 189 continue; 190 case 'Z': 191 if (!t->tm_zone || !_add(t->tm_zone)) 192 return(0); 193 continue; 194 case '%': 195 /* 196 * X311J/88-090 (4.12.3.5): if conversion char is 197 * undefined, behavior is undefined. Print out the 198 * character itself as printf(3) also does. 199 */ 200 default: 201 break; 202 } 203 if (!gsize--) 204 return(0); 205 *pt++ = *format; 206 } 207 return(gsize); 208 } 209 210 static 211 _conv(n, digits) 212 int n, digits; 213 { 214 static char buf[10]; 215 register char *p; 216 217 for (p = buf + sizeof(buf) - 2; n > 0 && p > buf; n /= 10, --digits) 218 *p-- = n % 10 + '0'; 219 while (p > buf && digits-- > 0) 220 *p-- = '0'; 221 return(_add(++p)); 222 } 223 224 static 225 _add(str) 226 register char *str; 227 { 228 for (;; ++pt, --gsize) { 229 if (!gsize) 230 return(0); 231 if (!(*pt = *str++)) 232 return(1); 233 } 234 } 235