2.11BSD#431 - /usr/src/lib/libc/gen/strftime.c

   1: /*
   2:  * Copyright (c) 1989, 1993
   3:  *	The Regents of the University of California.  All rights reserved.
   4:  *
   5:  * Redistribution and use in source and binary forms, with or without
   6:  * modification, are permitted provided that the following conditions
   7:  * are met:
   8:  * 1. Redistributions of source code must retain the above copyright
   9:  *    notice, this list of conditions and the following disclaimer.
  10:  * 2. Redistributions in binary form must reproduce the above copyright
  11:  *    notice, this list of conditions and the following disclaimer in the
  12:  *    documentation and/or other materials provided with the distribution.
  13:  * 3. All advertising materials mentioning features or use of this software
  14:  *    must display the following acknowledgement:
  15:  *	This product includes software developed by the University of
  16:  *	California, Berkeley and its contributors.
  17:  * 4. Neither the name of the University nor the names of its contributors
  18:  *    may be used to endorse or promote products derived from this software
  19:  *    without specific prior written permission.
  20:  *
  21:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31:  * SUCH DAMAGE.
  32:  */
  33: 
  34: #if defined(LIBC_SCCS) && !defined(lint)
  35: static char sccsid[] = "@(#)strftime.c	8.1.1 (2.11BSD) 1995/04/01";
  36: #endif /* LIBC_SCCS and not lint */
  37: 
  38: #include <sys/types.h>
  39: #include <sys/time.h>
  40: #include <tzfile.h>
  41: #include <string.h>
  42: 
  43: static char *Afmt[] = {
  44:     "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday",
  45:     "Saturday",
  46: };
  47: static char *Bfmt[] = {
  48:     "January", "February", "March", "April", "May", "June", "July",
  49:     "August", "September", "October", "November", "December",
  50: };
  51: 
  52: static size_t gsize;
  53: static char *pt;
  54: static int _add();
  55: static int _conv();
  56: static size_t _fmt();
  57: 
  58: size_t
  59: strftime(s, maxsize, format, t)
  60:     char *s;
  61:     size_t maxsize;
  62:     char *format;
  63:     struct tm *t;
  64: {
  65: 
  66:     pt = s;
  67:     if ((gsize = maxsize) < 1)
  68:         return(0);
  69:     if (_fmt(format, t)) {
  70:         *pt = '\0';
  71:         return(maxsize - gsize);
  72:     }
  73:     return(0);
  74: }
  75: 
  76: static size_t
  77: _fmt(format, t)
  78:     register char *format;
  79:     register struct tm *t;
  80: {
  81:     char    ch, *cp, junk[4];
  82: 
  83:     for (; *format; ++format) {
  84:         if (*format == '%')
  85:             switch(ch = *++format) {
  86:             case '\0':
  87:                 --format;
  88:                 break;
  89:             case 'A':
  90:             case 'a':
  91:                 if (t->tm_wday < 0 || t->tm_wday > 6)
  92:                     return(0);
  93:                 if  (ch == 'a')
  94:                     {
  95:                     bcopy(Afmt[t->tm_wday], junk, 3);
  96:                     junk[3] = '\0';
  97:                     cp = junk;
  98:                     }
  99:                 else
 100:                     cp = Afmt[t->tm_wday];
 101:                 if (!_add(cp))
 102:                     return(0);
 103:                 continue;
 104:             case 'B':
 105:             case 'b':
 106:             case 'h':
 107:                 if (t->tm_mon < 0 || t->tm_mon > 11)
 108:                     return(0);
 109:                 if  (ch == 'b')
 110:                     {
 111:                     bcopy(Bfmt[t->tm_mon], junk, 3);
 112:                     junk[3] = '\0';
 113:                     cp = junk;
 114:                     }
 115:                 else
 116:                     cp = Bfmt[t->tm_mon];
 117:                 if (!_add(cp))
 118:                     return(0);
 119:                 continue;
 120:             case 'C':
 121:                 if (!_fmt("%a %b %e %H:%M:%S %Y", t))
 122:                     return(0);
 123:                 continue;
 124:             case 'c':
 125:                 if (!_fmt("%m/%d/%y %H:%M:%S", t))
 126:                     return(0);
 127:                 continue;
 128:             case 'D':
 129:                 if (!_fmt("%m/%d/%y", t))
 130:                     return(0);
 131:                 continue;
 132:             case 'd':
 133:                 if (!_conv(t->tm_mday, 2, '0'))
 134:                     return(0);
 135:                 continue;
 136:             case 'e':
 137:                 if (!_conv(t->tm_mday, 2, ' '))
 138:                     return(0);
 139:                 continue;
 140:             case 'H':
 141:                 if (!_conv(t->tm_hour, 2, '0'))
 142:                     return(0);
 143:                 continue;
 144:             case 'I':
 145:                 if (!_conv(t->tm_hour % 12 ?
 146:                     t->tm_hour % 12 : 12, 2, '0'))
 147:                     return(0);
 148:                 continue;
 149:             case 'j':
 150:                 if (!_conv(t->tm_yday + 1, 3, '0'))
 151:                     return(0);
 152:                 continue;
 153:             case 'k':
 154:                 if (!_conv(t->tm_hour, 2, ' '))
 155:                     return(0);
 156:                 continue;
 157:             case 'l':
 158:                 if (!_conv(t->tm_hour % 12 ?
 159:                     t->tm_hour % 12 : 12, 2, ' '))
 160:                     return(0);
 161:                 continue;
 162:             case 'M':
 163:                 if (!_conv(t->tm_min, 2, '0'))
 164:                     return(0);
 165:                 continue;
 166:             case 'm':
 167:                 if (!_conv(t->tm_mon + 1, 2, '0'))
 168:                     return(0);
 169:                 continue;
 170:             case 'n':
 171:                 if (!_add("\n"))
 172:                     return(0);
 173:                 continue;
 174:             case 'p':
 175:                 if (!_add(t->tm_hour >= 12 ? "PM" : "AM"))
 176:                     return(0);
 177:                 continue;
 178:             case 'R':
 179:                 if (!_fmt("%H:%M", t))
 180:                     return(0);
 181:                 continue;
 182:             case 'r':
 183:                 if (!_fmt("%I:%M:%S %p", t))
 184:                     return(0);
 185:                 continue;
 186:             case 'S':
 187:                 if (!_conv(t->tm_sec, 2, '0'))
 188:                     return(0);
 189:                 continue;
 190:             case 'T':
 191:             case 'X':
 192:                 if (!_fmt("%H:%M:%S", t))
 193:                     return(0);
 194:                 continue;
 195:             case 't':
 196:                 if (!_add("\t"))
 197:                     return(0);
 198:                 continue;
 199:             case 'U':
 200:                 if (!_conv((t->tm_yday + 7 - t->tm_wday) / 7,
 201:                     2, '0'))
 202:                     return(0);
 203:                 continue;
 204:             case 'W':
 205:                 if (!_conv((t->tm_yday + 7 -
 206:                     (t->tm_wday ? (t->tm_wday - 1) : 6))
 207:                     / 7, 2, '0'))
 208:                     return(0);
 209:                 continue;
 210:             case 'w':
 211:                 if (!_conv(t->tm_wday, 1, '0'))
 212:                     return(0);
 213:                 continue;
 214:             case 'x':
 215:                 if (!_fmt("%m/%d/%y", t))
 216:                     return(0);
 217:                 continue;
 218:             case 'y':
 219:                 if (!_conv((t->tm_year + TM_YEAR_BASE)
 220:                     % 100, 2, '0'))
 221:                     return(0);
 222:                 continue;
 223:             case 'Y':
 224:                 if (!_conv(t->tm_year + TM_YEAR_BASE, 4, '0'))
 225:                     return(0);
 226:                 continue;
 227:             case 'Z':
 228:                 if (!t->tm_zone || !_add(t->tm_zone))
 229:                     return(0);
 230:                 continue;
 231:             case '%':
 232:             /*
 233: 			 * X311J/88-090 (4.12.3.5): if conversion char is
 234: 			 * undefined, behavior is undefined.  Print out the
 235: 			 * character itself as printf(3) does.
 236: 			 */
 237:             default:
 238:                 break;
 239:         }
 240:         if (!gsize--)
 241:             return(0);
 242:         *pt++ = *format;
 243:     }
 244:     return(gsize);
 245: }
 246: 
 247: static int
 248: _conv(n, digits, pad)
 249:     int n, digits, pad;
 250: {
 251:     static char buf[10];
 252:     register char *p;
 253: 
 254:     for (p = buf + sizeof(buf) - 2; n > 0 && p > buf; n /= 10, --digits)
 255:         *p-- = n % 10 + '0';
 256:     while (p > buf && digits-- > 0)
 257:         *p-- = pad;
 258:     return(_add(++p));
 259: }
 260: 
 261: static int
 262: _add(str)
 263:     register char *str;
 264: {
 265:     for (;; ++pt, --gsize) {
 266:         if (!gsize)
 267:             return(0);
 268:         if (!(*pt = *str++))
 269:             return(1);
 270:     }
 271: }

Defined functions

Defined variables