Check for timegm.

2006-03-23  Emmanuele Bassi  <ebassi@cvs.gnome.org>

	* configure.in: Check for timegm.

	* glib/gtimer.h:
	* glib/gtimer.c:
	* glib/glib.symbols:
	* docs/reference/glib/glib-sections.txt: Added g_time_val_to_iso8601
	and g_time_val_from_iso8601, to convert a GTimeVal to and from an
	ISO 8601 encoded date.

	* tests/testglib.c: Added test cases for g_time_val_to_iso8601()
	and g_time_val_from_iso8601() functions.

9 files changed, 253 insertions, 14 deletions

diff --git a/ChangeLog b/ChangeLog
index 1e2a8cd57..9234d7f5e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2006-03-23  Emmanuele Bassi  <ebassi@cvs.gnome.org>
+
+	* configure.in: Check for timegm.
+	
+	* glib/gtimer.h:
+	* glib/gtimer.c:
+	* glib/glib.symbols:
+	* docs/reference/glib/glib-sections.txt: Added g_time_val_to_iso8601
+	and g_time_val_from_iso8601, to convert a GTimeVal to and from an
+	ISO 8601 encoded date.
+
+	* tests/testglib.c: Added test cases for g_time_val_to_iso8601()
+	and g_time_val_from_iso8601() functions.
+
 2006-03-20  Vladimer Sichinava  <vlsichinava@gmail.com>
 
         * configure.in: Added "ka" (Georgian) to ALL_LINGUAS
diff --git a/ChangeLog.pre-2-10 b/ChangeLog.pre-2-10
index 1e2a8cd57..9234d7f5e 100644
--- a/ChangeLog.pre-2-10
+++ b/ChangeLog.pre-2-10
@@ -1,3 +1,17 @@
+2006-03-23  Emmanuele Bassi  <ebassi@cvs.gnome.org>
+
+	* configure.in: Check for timegm.
+	
+	* glib/gtimer.h:
+	* glib/gtimer.c:
+	* glib/glib.symbols:
+	* docs/reference/glib/glib-sections.txt: Added g_time_val_to_iso8601
+	and g_time_val_from_iso8601, to convert a GTimeVal to and from an
+	ISO 8601 encoded date.
+
+	* tests/testglib.c: Added test cases for g_time_val_to_iso8601()
+	and g_time_val_from_iso8601() functions.
+
 2006-03-20  Vladimer Sichinava  <vlsichinava@gmail.com>
 
         * configure.in: Added "ka" (Georgian) to ALL_LINGUAS
diff --git a/ChangeLog.pre-2-12 b/ChangeLog.pre-2-12
index 1e2a8cd57..9234d7f5e 100644
--- a/ChangeLog.pre-2-12
+++ b/ChangeLog.pre-2-12
@@ -1,3 +1,17 @@
+2006-03-23  Emmanuele Bassi  <ebassi@cvs.gnome.org>
+
+	* configure.in: Check for timegm.
+	
+	* glib/gtimer.h:
+	* glib/gtimer.c:
+	* glib/glib.symbols:
+	* docs/reference/glib/glib-sections.txt: Added g_time_val_to_iso8601
+	and g_time_val_from_iso8601, to convert a GTimeVal to and from an
+	ISO 8601 encoded date.
+
+	* tests/testglib.c: Added test cases for g_time_val_to_iso8601()
+	and g_time_val_from_iso8601() functions.
+
 2006-03-20  Vladimer Sichinava  <vlsichinava@gmail.com>
 
         * configure.in: Added "ka" (Georgian) to ALL_LINGUAS
diff --git a/configure.in b/configure.in
index 8c5144f0e..2f32722bc 100644
--- a/configure.in
+++ b/configure.in
@@ -528,6 +528,8 @@ AC_CHECK_FUNCS(valloc)
 
 AC_CHECK_FUNCS(atexit on_exit)
 
+AC_CHECK_FUNCS(timegm)
+
 AC_CHECK_SIZEOF(char)
 AC_CHECK_SIZEOF(short)
 AC_CHECK_SIZEOF(long)
diff --git a/docs/reference/glib/glib-sections.txt b/docs/reference/glib/glib-sections.txt
index ed5bb2018..0def2c675 100644
--- a/docs/reference/glib/glib-sections.txt
+++ b/docs/reference/glib/glib-sections.txt
@@ -1155,6 +1155,8 @@ GTimeVal
 g_get_current_time
 g_usleep
 g_time_val_add
+g_time_val_from_iso8601
+g_time_val_to_iso8601
 
 <SUBSECTION>
 GDate
diff --git a/glib/glib.symbols b/glib/glib.symbols
index 2b88fec02..71e6974de 100644
--- a/glib/glib.symbols
+++ b/glib/glib.symbols
@@ -1111,6 +1111,8 @@ g_timer_reset
 g_timer_start
 g_timer_stop
 g_time_val_add
+g_time_val_from_iso8601
+g_time_val_to_iso8601 G_GNUC_MALLOC
 g_usleep
 #endif
 #endif
diff --git a/glib/gtimer.c b/glib/gtimer.c
index 6a6a06e3c..2d7678b6b 100644
--- a/glib/gtimer.c
+++ b/glib/gtimer.c
@@ -31,6 +31,8 @@
 #include "config.h"
 #include "glibconfig.h"
 
+#include <stdlib.h>
+
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif /* HAVE_UNISTD_H */
@@ -308,5 +310,158 @@ g_time_val_add (GTimeVal *time_, glong microseconds)
     }
 }
 
+/* converts a broken down date representation, relative to UTC, to
+ * a timestamp; it uses timegm() if it's available.
+ */
+static time_t
+mktime_utc (struct tm *tm)
+{
+  time_t retval;
+  
+#ifndef HAVE_TIMEGM
+  static const gint days_before[] =
+  {
+    0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
+  };
+#endif
+
+#ifndef HAVE_TIMEGM
+  if (tm->tm_mon < 0 || tm->tm_mon > 11)
+    return (time_t) -1;
+
+  retval = (tm->tm_year - 70) * 365;
+  retval += (tm->tm_year - 68) / 4;
+  retval += days_before[tm->tm_mon] + tm->tm_mday - 1;
+  
+  if (tm->tm_year % 4 == 2 && tm->tm_mon < 2)
+    retval -= 1;
+  
+  retval = ((((retval * 24) + tm->tm_hour) * 60) + tm->tm_min) * 60 + tm->tm_sec;
+#else
+  retval = timegm (tm);
+#endif /* !HAVE_TIMEGM */
+  
+  return retval;
+}
+
+/**
+ * g_time_val_from_iso8601:
+ * @iso_date: a ISO 8601 encoded date string
+ * @time_: a #GTimeVal
+ *
+ * Converts a string containing an ISO 8601 encoded date and time
+ * to a #GTimeVal and puts it into @time_.
+ *
+ * Return value: %TRUE if the conversion was successful.
+ *
+ * Since: 2.10
+ */
+gboolean
+g_time_val_from_iso8601 (const gchar *iso_date,
+			 GTimeVal    *time_)
+{
+  struct tm tm;
+  long val;
+
+  g_return_val_if_fail (iso_date != NULL, FALSE);
+  g_return_val_if_fail (time_ != NULL, FALSE);
+
+  val = strtoul (iso_date, (char **)&iso_date, 10);
+  if (*iso_date == '-')
+    {
+      /* YYYY-MM-DD */
+      tm.tm_year = val - 1900;
+      iso_date++;
+      tm.tm_mon = strtoul (iso_date, (char **)&iso_date, 10) - 1;
+      
+      if (*iso_date++ != '-')
+       	return FALSE;
+      
+      tm.tm_mday = strtoul (iso_date, (char **)&iso_date, 10);
+    }
+  else
+    {
+      /* YYYYMMDD */
+      tm.tm_mday = val % 100;
+      tm.tm_mon = (val % 10000) / 100 - 1;
+      tm.tm_year = val / 10000 - 1900;
+    }
+
+  if (*iso_date++ != 'T')
+    return FALSE;
+  
+  val = strtoul (iso_date, (char **)&iso_date, 10);
+  if (*iso_date == ':')
+    {
+      /* hh:mm:ss */
+      tm.tm_hour = val;
+      iso_date++;
+      tm.tm_min = strtoul (iso_date, (char **)&iso_date, 10);
+      
+      if (*iso_date++ != ':')
+        return FALSE;
+      
+      tm.tm_sec = strtoul (iso_date, (char **)&iso_date, 10);
+    }
+  else
+    {
+      /* hhmmss */
+      tm.tm_sec = val % 100;
+      tm.tm_min = (val % 10000) / 100;
+      tm.tm_hour = val / 10000;
+    }
+
+  time_->tv_sec = mktime_utc (&tm);
+  time_->tv_usec = 1;
+  
+  if (*iso_date == '.')
+    time_->tv_usec = strtoul (iso_date + 1, (char **)&iso_date, 10);
+    
+  if (*iso_date == '+' || *iso_date == '-')
+    {
+      gint sign = (*iso_date == '+') ? -1 : 1;
+      
+      val = 60 * strtoul (iso_date + 1, (char **)&iso_date, 10);
+      
+      if (*iso_date == ':')
+	val = 60 * val + strtoul (iso_date + 1, NULL, 10);
+      else
+        val = 60 * (val / 100) + (val % 100);
+
+      time_->tv_sec += (time_t) (val * sign);
+    }
+
+  return TRUE;
+}
+
+/**
+ * g_time_val_to_iso8601:
+ * @time_: a #GTimeVal
+ * 
+ * Converts @time_ into a ISO 8601 encoded string, relative to the
+ * Coordinated Universal Time (UTC).
+ *
+ * Return value: a newly allocated string containing a ISO 8601 date
+ *
+ * Since: 2.10
+ */
+gchar *
+g_time_val_to_iso8601 (GTimeVal *time_)
+{
+  gchar *retval;
+
+  g_return_val_if_fail (time_->tv_usec >= 0 && time_->tv_usec < G_USEC_PER_SEC, NULL);
+
+#define ISO_8601_LEN 	21
+#define ISO_8601_FORMAT "%Y-%m-%dT%H:%M:%SZ"
+  retval = g_new0 (gchar, ISO_8601_LEN + 1);
+  
+  strftime (retval, ISO_8601_LEN,
+	    ISO_8601_FORMAT,
+	    gmtime (&(time_->tv_sec)));
+  
+  return retval;
+}
+
 #define __G_TIMER_C__
 #include "galiasdef.c"
diff --git a/glib/gtimer.h b/glib/gtimer.h
index fc434d06a..d602ae1b9 100644
--- a/glib/gtimer.h
+++ b/glib/gtimer.h
@@ -39,19 +39,22 @@ typedef struct _GTimer		GTimer;
 
 #define G_USEC_PER_SEC 1000000
 
-GTimer* g_timer_new	(void);
-void	g_timer_destroy (GTimer	  *timer);
-void	g_timer_start	(GTimer	  *timer);
-void	g_timer_stop	(GTimer	  *timer);
-void	g_timer_reset	(GTimer	  *timer);
-void	g_timer_continue	(GTimer   *timer);
-gdouble g_timer_elapsed (GTimer	  *timer,
-			 gulong	  *microseconds);
-
-void    g_usleep        (gulong    microseconds);
-
-void    g_time_val_add  (GTimeVal *time_, 
-                         glong     microseconds);
+GTimer*  g_timer_new	         (void);
+void	 g_timer_destroy         (GTimer      *timer);
+void	 g_timer_start	         (GTimer      *timer);
+void	 g_timer_stop	         (GTimer      *timer);
+void	 g_timer_reset	         (GTimer      *timer);
+void	 g_timer_continue        (GTimer      *timer);
+gdouble  g_timer_elapsed         (GTimer      *timer,
+				  gulong      *microseconds);
+
+void     g_usleep                (gulong       microseconds);
+
+void     g_time_val_add          (GTimeVal    *time_, 
+                                  glong        microseconds);
+gboolean g_time_val_from_iso8601 (const gchar *iso_date,
+				  GTimeVal    *time_);
+gchar*   g_time_val_to_iso8601   (GTimeVal    *time_) G_GNUC_MALLOC;
 
 G_END_DECLS
 
diff --git a/tests/testglib.c b/tests/testglib.c
index 42f4fce9a..0aadec72a 100644
--- a/tests/testglib.c
+++ b/tests/testglib.c
@@ -475,7 +475,9 @@ main (int   argc,
   gint morenums[10] = { 8, 9, 7, 0, 3, 2, 5, 1, 4, 6};
   gchar *string;
   gint value = 120; 
-  gint *pvalue=NULL; 
+  gint *pvalue=NULL;
+  GTimeVal ref_date, date;
+  gchar *date_str;
   
   gchar *mem[10000], *tmp_string = NULL, *tmp_string_2;
   gint i, j;
@@ -1176,6 +1178,37 @@ main (int   argc,
   g_timer_destroy(timer);
   g_timer_destroy(timer2);
 
+#define REF_SEC_UTC  343737360
+#define REF_STR_UTC  "1980-11-22T10:36:00Z"
+#define REF_STR_CEST "1980-11-22T12:36:00+02:00"
+#define REF_STR_EST  "1980-11-22T05:36:00-05:00"
+
+  g_print ("checking g_time_val_from_iso8601...\n");
+  ref_date.tv_sec = REF_SEC_UTC;
+  ref_date.tv_usec = 0;
+  g_assert (g_time_val_from_iso8601 (REF_STR_UTC, &date) != FALSE);
+  g_print ("\t=> UTC stamp = %ld (should be: %ld) (%ld off)\n", date.tv_sec, ref_date.tv_sec, date.tv_sec - ref_date.tv_sec);
+  g_assert (date.tv_sec == ref_date.tv_sec);
+
+  g_assert (g_time_val_from_iso8601 (REF_STR_CEST, &date) != FALSE);
+  g_print ("\t=> CEST stamp = %ld (should be: %ld) (%ld off)\n", date.tv_sec, ref_date.tv_sec, date.tv_sec - ref_date.tv_sec);
+  g_assert (date.tv_sec == ref_date.tv_sec);
+  
+  g_assert (g_time_val_from_iso8601 (REF_STR_EST, &date) != FALSE);
+  g_print ("\t=> EST stamp = %ld (should be: %ld) (%ld off)\n", date.tv_sec, ref_date.tv_sec, date.tv_sec - ref_date.tv_sec);
+  g_assert (date.tv_sec == ref_date.tv_sec);
+  g_print ("ok\n");
+  
+  g_print ("checking g_time_val_to_iso8601...\n");
+  ref_date.tv_sec = REF_SEC_UTC;
+  ref_date.tv_usec = 1;
+  date_str = g_time_val_to_iso8601 (&ref_date);
+  g_assert (date_str != NULL);
+  g_print ("\t=> date string = %s (should be: %s)\n", date_str, REF_STR_UTC);
+  g_assert (strcmp (date_str, REF_STR_UTC) == 0);
+  g_free (date_str);
+  g_print ("ok\n");
+
   g_print ("checking g_ascii_strcasecmp...");
   g_assert (g_ascii_strcasecmp ("FroboZZ", "frobozz") == 0);
   g_assert (g_ascii_strcasecmp ("frobozz", "frobozz") == 0);