net/khttpd/rfc_time.c

   1 /*
   2
   3 Functions related to time:
   4
   5 1) rfc (string) time to unix-time
   6 2) unix-time to rfc (string) time
   7 3) current time to rfc (string) time for the "Date:" header
   8
   9 */
  10
  11 /****************************************************************
  12  *      This program is free software; you can redistribute it and/or modify
  13  *      it under the terms of the GNU General Public License as published by
  14  *      the Free Software Foundation; either version 2, or (at your option)
  15  *      any later version.
  16  *
  17  *      This program is distributed in the hope that it will be useful,
  18  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *      GNU General Public License for more details.
  21  *
  22  *      You should have received a copy of the GNU General Public License
  23  *      along with this program; if not, write to the Free Software
  24  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  *
  26  ****************************************************************/
  27
  28 #include <linux/time.h>
  29 #include <linux/kernel.h>
  30 #include <linux/malloc.h>
  31 #include <linux/ctype.h>
  32
  33
  34 #include "times.h"
  35 #include "prototypes.h"
  36 static char *dayName[7] = {
  37         "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
  38 };
  39
  40 static char *monthName[12] = {
  41         "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  42         "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
  43 };
  44
  45
  46 char CurrentTime[64];
  47 int  CurrentTime_i;
  48
  49
  50 static char itoa_h[60]={'0','0','0','0','0','0','0','0','0','0',
  51                  '1','1','1','1','1','1','1','1','1','1',
  52                  '2','2','2','2','2','2','2','2','2','2',
  53                  '3','3','3','3','3','3','3','3','3','3',
  54                  '4','4','4','4','4','4','4','4','4','4',
  55                  '5','5','5','5','5','5','5','5','5','5'};
  56
  57 static char itoa_l[60]={'0','1','2','3','4','5','6','7','8','9',
  58                  '0','1','2','3','4','5','6','7','8','9',
  59                  '0','1','2','3','4','5','6','7','8','9',
  60                  '0','1','2','3','4','5','6','7','8','9',
  61                  '0','1','2','3','4','5','6','7','8','9',
  62                  '0','1','2','3','4','5','6','7','8','9'};
  63 void time_Unix2RFC(const time_t Zulu,char *Buffer)
  64 {
  65         int Y=0,M=0,D=0;
  66         int H=0,Min=0,S=0,WD=0;
  67         int I,I2;
  68         time_t rest;
  69
  70
  71
  72         I=0;
  73         while (I<KHTTPD_NUMYEARS)
  74         {
  75                 if (TimeDays[I][0]>Zulu)
  76                    break;
  77                 I++;
  78         }
  79
  80         Y=--I;
  81         if (I<0)
  82         {
  83                 Y=0;
  84                 goto BuildYear;
  85         }
  86         I2=0;
  87         while (I2<=12)
  88         {
  89                 if (TimeDays[I][I2]>Zulu)
  90                    break;
  91                 I2++;
  92         }
  93
  94         M=I2-1;
  95
  96         rest=Zulu - TimeDays[Y][M];
  97         WD=WeekDays[Y][M];
  98         D=rest/86400;
  99         rest=rest%86400;
 100         WD+=D;
 101         WD=WD%7;
 102         H=rest/3600;
 103         rest=rest%3600;
 104         Min=rest/60;
 105         rest=rest%60;
 106         S=rest;
 107
 108 BuildYear:
 109         Y+=KHTTPD_YEAROFFSET;
 110
 111
 112         /* Format:  Day, 01 Mon 1999 01:01:01 GMT */
 113
 114 /*
 115         We want to do
 116
 117         sprintf( Buffer, "%s, %02i %s %04i %02i:%02i:%02i GMT",
 118                 dayName[ WD ], D+1, monthName[ M ], Y,
 119                 H, Min, S
 120         );
 121
 122         but this is very expensive. Since the string is fixed length,
 123         it is filled manually.
 124 */
 125         Buffer[0]=dayName[WD][0];
 126         Buffer[1]=dayName[WD][1];
 127         Buffer[2]=dayName[WD][2];
 128         Buffer[3]=',';
 129         Buffer[4]=' ';
 130         Buffer[5]=itoa_h[D+1];
 131         Buffer[6]=itoa_l[D+1];
 132         Buffer[7]=' ';
 133         Buffer[8]=monthName[M][0];
 134         Buffer[9]=monthName[M][1];
 135         Buffer[10]=monthName[M][2];
 136         Buffer[11]=' ';
 137         Buffer[12]=itoa_l[Y/1000];
 138         Buffer[13]=itoa_l[(Y/100)%10];
 139         Buffer[14]=itoa_l[(Y/10)%10];
 140         Buffer[15]=itoa_l[Y%10];
 141         Buffer[16]=' ';
 142         Buffer[17]=itoa_h[H];
 143         Buffer[18]=itoa_l[H];
 144         Buffer[19]=':';
 145         Buffer[20]=itoa_h[Min];
 146         Buffer[21]=itoa_l[Min];
 147         Buffer[22]=':';
 148         Buffer[23]=itoa_h[S];
 149         Buffer[24]=itoa_l[S];
 150         Buffer[25]=' ';
 151         Buffer[26]='G';
 152         Buffer[27]='M';
 153         Buffer[28]='T';
 154         Buffer[29]=0;
 155
 156
 157
 158
 159 }
 160
 161 void UpdateCurrentDate(void)
 162 {
 163    struct timeval tv;
 164
 165    do_gettimeofday(&tv);
 166    if (CurrentTime_i!=tv.tv_sec)
 167            time_Unix2RFC(tv.tv_sec,CurrentTime);
 168
 169    CurrentTime_i = tv.tv_sec;
 170 }
 171
 172 static int MonthHash[32] = {0,0,7,0,0,0,0,0,0,0,0,3,0,0,0,2,6,0,5,0,9,8,4,0,0,11,1,10,0,0,0,0};
 173
 174 #define is_digit(c)     ((c) >= '0' && (c) <= '9')
 175
 176 __inline static int skip_atoi(char **s)
 177 {
 178         int i=0;
 179
 180         while (is_digit(**s))
 181                 i = i*10 + *((*s)++) - '0';
 182         return i;
 183 }
 184
 185 time_t mimeTime_to_UnixTime(char *Q)
 186 {
 187         int Y,M,D,H,Min,S;
 188         unsigned int Hash;
 189         time_t Temp;
 190         char *s,**s2;
 191
 192         s=Q;
 193         s2=&s;
 194
 195         if (strlen(s)<30) return 0;
 196         if (s[3]!=',') return 0;
 197         if (s[19]!=':') return 0;
 198
 199         s+=5; /* Skip day of week */
 200         D = skip_atoi(s2);  /*  Day of month */
 201         s++;
 202         Hash = (unsigned char)s[0]+(unsigned char)s[2];
 203         Hash = (Hash<<1) + (unsigned char)s[1];
 204         Hash = (Hash&63)>>1;
 205         M = MonthHash[Hash];
 206         s+=4;
 207         Y = skip_atoi(s2); /* Year */
 208         s++;
 209         H = skip_atoi(s2); /* Hour */
 210         s++;
 211         Min = skip_atoi(s2); /* Minutes */
 212         s++;
 213         S = skip_atoi(s2); /* Seconds */
 214         s++;
 215         if ((s[0]!='G')||(s[1]!='M')||(s[2]!='T'))
 216         {
 217                 return 0; /* No GMT */
 218         }
 219
 220         if (Y<KHTTPD_YEAROFFSET) Y = KHTTPD_YEAROFFSET;
 221         if (Y>KHTTPD_YEAROFFSET+9) Y = KHTTPD_YEAROFFSET+9;
 222
 223         Temp =  TimeDays[Y-KHTTPD_YEAROFFSET][M];
 224         Temp += D*86400+H*3600+Min*60+S;
 225
 226         return Temp;
 227 }