tstrtotm.c - plan9port - [fork] Plan 9 from user space
  HTML git clone git://src.adamsgaard.dk/plan9port
   DIR Log
   DIR Files
   DIR Refs
   DIR README
   DIR LICENSE
       ---
       tstrtotm.c (1902B)
       ---
            1 #include <u.h>
            2 #include <libc.h>
            3 #include <ctype.h>
            4 
            5 static char*
            6 skiptext(char *q)
            7 {
            8         while(*q!='\0' && *q!=' ' && *q!='\t' && *q!='\r' && *q!='\n')
            9                 q++;
           10         return q;
           11 }
           12 
           13 static char*
           14 skipwhite(char *q)
           15 {
           16         while(*q==' ' || *q=='\t' || *q=='\r' || *q=='\n')
           17                 q++;
           18         return q;
           19 }
           20 
           21 static char* months[] = {
           22         "jan", "feb", "mar", "apr",
           23         "may", "jun", "jul", "aug",
           24         "sep", "oct", "nov", "dec"
           25 };
           26 
           27 static int
           28 strcmplwr(char *a, char *b, int n)
           29 {
           30         char *eb;
           31 
           32         eb = b+n;
           33         while(*a && *b && b<eb){
           34                 if(tolower(*a) != tolower(*b))
           35                         return 1;
           36                 a++;
           37                 b++;
           38         }
           39         if(b==eb)
           40                 return 0;
           41         return *a != *b;
           42 }
           43 
           44 int
           45 strtotm(char *p, Tm *tmp)
           46 {
           47         char *q, *r;
           48         int j;
           49         Tm tm;
           50         int delta;
           51 
           52         delta = 0;
           53         memset(&tm, 0, sizeof(tm));
           54         tm.mon = -1;
           55         tm.hour = -1;
           56         tm.min = -1;
           57         tm.year = -1;
           58         tm.mday = -1;
           59         for(p=skipwhite(p); *p; p=skipwhite(q)){
           60                 q = skiptext(p);
           61 
           62                 /* look for time in hh:mm[:ss] */
           63                 if(r = memchr(p, ':', q-p)){
           64                         tm.hour = strtol(p, 0, 10);
           65                         tm.min = strtol(r+1, 0, 10);
           66                         if(r = memchr(r+1, ':', q-(r+1)))
           67                                 tm.sec = strtol(r+1, 0, 10);
           68                         else
           69                                 tm.sec = 0;
           70                         continue;
           71                 }
           72 
           73                 /* look for month */
           74                 for(j=0; j<12; j++)
           75                         if(strcmplwr(p, months[j], 3)==0){
           76                                 tm.mon = j;
           77                                 break;
           78                         }
           79 
           80                 if(j!=12)
           81                         continue;
           82 
           83                 /* look for time zone [A-Z][A-Z]T */
           84                 if(q-p==3 && 'A' <= p[0] && p[0] <= 'Z'
           85                 && 'A' <= p[1] && p[1] <= 'Z' && p[2] == 'T'){
           86                         strecpy(tm.zone, tm.zone+4, p);
           87                         continue;
           88                 }
           89 
           90                 if(p[0]=='+'||p[0]=='-')
           91                 if(q-p==5 && strspn(p+1, "0123456789") == 4){
           92                         delta = (((p[1]-'0')*10+p[2]-'0')*60+(p[3]-'0')*10+p[4]-'0')*60;
           93                         if(p[0] == '-')
           94                                 delta = -delta;
           95                         continue;
           96                 }
           97                 if(strspn(p, "0123456789") == q-p){
           98                         j = strtol(p, nil, 10);
           99                         if(1 <= j && j <= 31)
          100                                 tm.mday = j;
          101                         if(j >= 1900)
          102                                 tm.year = j-1900;
          103                 }
          104         }
          105 
          106         if(tm.mon<0 || tm.year<0
          107         || tm.hour<0 || tm.min<0
          108         || tm.mday<0)
          109                 return -1;
          110 
          111         *tmp = *localtime(tm2sec(&tm)-delta);
          112         return 0;
          113 }