apps/plugins/lua/strftime.c

   1 #include <sys/types.h>
   2 #include <time.h>
   3 #include "plugin.h"
   4
   5 static const char   sweekdays [7] [4] = {
   6     "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
   7 };
   8 static const char   weekdays [7] [10] = {
   9     "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
  10 };
  11 static const char   smonths [12] [4] = {
  12     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  13     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  14 };
  15 static const char*  months [12] = {
  16     "January", "February", "March", "April", smonths[5-1], "June",
  17     "July", "August", "September", "October", "November", "December"
  18 };
  19 static const char   ampm [4] [3] = {
  20     "am", "pm",
  21     "AM", "PM"
  22 };
  23
  24 static void i2a ( char* dest,unsigned long x )
  25 {
  26     int  div = 10;
  27     *dest++ = x/div + '0';
  28     *dest++ = x%div + '0';
  29     *dest++ = '\0';
  30 }
  31
  32 size_t  strftime ( char* dst, size_t max, const char* format, const struct tm* tm )
  33 {
  34     char*         p = dst;
  35     const char*   src;
  36     unsigned long no;
  37     char          buf [5];
  38
  39     if (!max) return 0;
  40     for ( ; *format != '\0'; format++ ) {
  41     if (*format == '%') {
  42         if (*++format == '%') {
  43             *p++ = '%';
  44         }
  45         else
  46 again:
  47         switch (*format) {
  48 //          case '%': *p++ = '%';                break;         // reduce size of jump table
  49         case 'n': *p++ = '\n';               break;
  50         case 't': *p++ = '\t';               break;
  51         case 'O': case 'E': ++format; goto again;
  52         case 'c': src = "%b %a %d %k:%M:%S %Z %Y";           goto _strf;
  53         case 'r': src = "%I:%M:%S %p";                       goto _strf;
  54         case 'R': src = "%H:%M";                 goto _strf;
  55         case 'x': src = "%b %a %d";              goto _strf;
  56         case 'X': src = "%k:%M:%S";              goto _strf;
  57         case 'D': src = "%m/%d/%y";              goto _strf;
  58         case 'T': src = "%H:%M:%S";
  59            _strf: p  += strftime (p, (size_t)(dst+max-p), src, tm);      break;
  60         case 'a': src = sweekdays [tm->tm_wday];         goto _str;
  61         case 'A': src = weekdays  [tm->tm_wday];         goto _str;
  62         case 'h':
  63         case 'b': src = smonths   [tm->tm_mon];          goto _str;
  64         case 'B': src = months    [tm->tm_mon];          goto _str;
  65         case 'p': src = ampm [tm->tm_hour > 12 ? 3 : 2]; goto _str;
  66         case 'P': src = ampm [tm->tm_hour > 12 ? 1 : 0]; goto _str;
  67         case 'C': no  = tm->tm_year/100 + 19;        goto _no;
  68         case 'd': no  = tm->tm_mday;                 goto _no;
  69         case 'e': no  = tm->tm_mday;                 goto _nos;
  70         case 'H': no  = tm->tm_hour;                 goto _no;
  71         case 'I': no  = tm->tm_hour % 12;            goto _no;
  72         case 'j': no  = tm->tm_yday;                 goto _no;
  73         case 'k': no  = tm->tm_hour;                 goto _nos;
  74         case 'l': no  = tm->tm_hour % 12;            goto _nos;
  75         case 'm': no  = tm->tm_mon + 1;                  goto _no;
  76         case 'M': no  = tm->tm_min;                  goto _no;
  77         case 'S': no  = tm->tm_sec;                  goto _no;
  78         case 'u': no  = tm->tm_wday ? tm->tm_wday : 7;   goto _no;
  79         case 'w': no  = tm->tm_wday;                     goto _no;
  80         case 'U': no  = (tm->tm_yday - tm->tm_wday + 7) / 7; goto _no;
  81         case 'W': no  = (tm->tm_yday - (tm->tm_wday - 1 + 7) % 7 + 7) / 7; goto _no;
  82         case 's': {
  83             time_t t =
  84 #if CONFIG_RTC
  85                 rb->mktime((struct tm*)tm)
  86 #else
  87                 0
  88 #endif
  89             ;
  90             char buf[101];
  91             char* c;
  92             buf[100]=0;
  93             for (c=buf+99; c>buf; --c) {
  94               *c=(t%10)+'0';
  95               t/=10;
  96               if (!t) break;
  97             }
  98             src=c;
  99             goto _str;
 100               }
 101         case 'Z':
 102 #ifdef WANT_TZFILE_PARSER
 103               tzset(); src = tzname[0];
 104 #else
 105               src = "[unknown timezone]";
 106 #endif
 107               goto _str;
 108         case 'Y': i2a ( buf+0, (unsigned int)(tm->tm_year / 100 + 19) );
 109               i2a ( buf+2, (unsigned int)(tm->tm_year % 100) );
 110               src = buf;
 111               goto _str;
 112         case 'y': no  = tm->tm_year % 100;           goto _no;
 113          _no: i2a ( buf, no );               /* append number 'no' */
 114               src = buf;
 115               goto _str;
 116         _nos: i2a ( buf, no );               /* the same, but '0'->' ' */
 117               if (buf[0] == '0')
 118               buf[0] = ' ';
 119               src = buf;
 120         _str: while (*src  &&  p < dst+max)      /* append string */
 121               *p++ = *src++;
 122               break;
 123         };
 124     } else {
 125         *p++ = *format;
 126     }
 127
 128     if (p >= dst+max)
 129         break;
 130     }
 131
 132     *p = '\0';
 133     return p - dst;
 134 }
 135
 136