src/unix.c

   1 #include "isds_priv.h"
   2 #include <stdio.h>
   3 #include <stdlib.h> /* for getenv */
   4 #include <string.h>
   5 #include <time.h>
   6 #include "isds.h"
   7 #include "utils.h"
   8
   9 static char *tz_orig; /* Copy of original TZ variable */
  10
  11 #if HAVE_LIBCURL
  12 /* Convert UTF-8 @string representation of ISO 8601 date to @time.
  13  * XXX: Not all ISO formats are supported */
  14 _hidden isds_error _isds_datestring2tm(const xmlChar *string, struct tm *time) {
  15     char *offset;
  16     if (!string || !time) return IE_INVAL;
  17
  18     memset(time, 0, sizeof(*time));
  19
  20     /* xsd:date is ISO 8601 string, thus ASCII */
  21     offset = strptime((char*)string, "%Y-%m-%d", time);
  22     if (offset && *offset == '\0')
  23         return IE_SUCCESS;
  24
  25     offset = strptime((char*)string, "%Y%m%d", time);
  26     if (offset && *offset == '\0')
  27         return IE_SUCCESS;
  28
  29     offset = strptime((char*)string, "%Y-%j", time);
  30     if (offset && *offset == '\0') {
  31         _isds_yday2mday(time);
  32         return IE_SUCCESS;
  33     }
  34
  35     return IE_NOTSUP;
  36 }
  37 #endif
  38
  39 /* Switches time zone to UTC.
  40  * XXX: This is not reentrant and not thread-safe */
  41 static void _isds_switch_tz_to_utc(void) {
  42     char *tz;
  43
  44     tz = getenv("TZ");
  45     if (tz) {
  46         tz_orig = strdup(tz);
  47         if (!tz_orig)
  48             PANIC("Can not back original time zone up");
  49     } else {
  50         tz_orig = NULL;
  51     }
  52
  53     if (setenv("TZ", "", 1))
  54             PANIC("Can not change time zone to UTC temporarily");
  55
  56     tzset();
  57 }
  58
  59
  60 /* Switches time zone to original value.
  61  * XXX: This is not reentrant and not thread-safe */
  62 static void _isds_switch_tz_to_native(void) {
  63     if (tz_orig) {
  64         if (setenv("TZ", tz_orig, 1))
  65             PANIC("Can not restore time zone by setting TZ variable");
  66         free(tz_orig);
  67         tz_orig = NULL;
  68     } else {
  69         if(unsetenv("TZ"))
  70             PANIC("Can not restore time zone by unsetting TZ variable");
  71     }
  72     tzset();
  73 }
  74
  75 /* Convert UTC broken time to time_t.
  76  * @broken_utc it time in UTC in broken format. Despite its content is not
  77  * touched, it'sw not-const because underlying POSIX function has non-const
  78  * signature.
  79  * @return (time_t) -1 in case of error */
  80 _hidden time_t _isds_timegm(struct tm *broken_utc) {
  81     time_t ret;
  82
  83     _isds_switch_tz_to_utc();
  84     ret = mktime(broken_utc);
  85     _isds_switch_tz_to_native();
  86
  87     return ret;
  88 }