[glib] GDateTime: use nl_langinfo() when available

[Matthias Clasen <matthiasc src gnome org>]

commit 527dc867225ae815356d2d1a72213abe981bd067
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Aug 21 23:48:07 2011 -0400

    GDateTime: use nl_langinfo() when available
    
    This makes g_date_time_format() react to LC_TIME, which is
    what people expect.
    
    Translators: this change means that the GDateTime strings
    are only used when the C library does not already provide
    suitable translated strings for these (month names, etc).

 configure.ac     |   17 +++++++++++++++++
 glib/gdatetime.c |   38 ++++++++++++++++++++++++++++++++++----
 2 files changed, 51 insertions(+), 4 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 2158831..5ef55ce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1309,6 +1309,23 @@ if test x$glib_cv_langinfo_codeset = xyes; then
   AC_DEFINE(HAVE_CODESET,1,[Have nl_langinfo (CODESET)])
 fi
 
+dnl Check for nl_langinfo and LC_TIME parts that are needed in gdatetime.c
+AC_CACHE_CHECK([for nl_langinfo (PM_STR)],glib_cv_langinfo_time,[
+        AC_TRY_COMPILE([#include <langinfo.h>],
+                [char *str;
+                 str = nl_langinfo (PM_STR);
+                 str = nl_langinfo (D_FMT);
+                 str = nl_langinfo (T_FMT);
+                 str = nl_langinfo (MON_1);
+                 str = nl_langinfo (ABMON_12);
+                 str = nl_langinfo (DAY_1);
+                 str = nl_langinfo (ABDAY_7);],
+                [glib_cv_langinfo_time=yes],
+                [glib_cv_langinfo_time=no])])
+if test x$glib_cv_langinfo_time = xyes; then
+  AC_DEFINE(HAVE_LANGINFO_TIME,1,[Have nl_langinfo (PM_STR)])
+fi
+
 dnl ****************************************
 dnl *** posix_memalign                   ***
 dnl ****************************************
diff --git a/glib/gdatetime.c b/glib/gdatetime.c
index aa55ede..e92c68c 100644
--- a/glib/gdatetime.c
+++ b/glib/gdatetime.c
@@ -163,6 +163,34 @@ static const guint16 days_in_year[2][13] =
   {  0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
 };
 
+#ifdef HAVE_LANGINFO_TIME
+
+#define GET_AMPM(d) ((g_date_time_get_hour (d) < 12) ? \
+                     nl_langinfo (AM_STR) : \
+                     nl_langinfo (PM_STR))
+
+#define PREFERRED_DATE_FMT nl_langinfo (D_FMT)
+#define PREFERRED_TIME_FMT nl_langinfo (T_FMT)
+
+static const gint weekday_item[2][7] =
+{
+  { ABDAY_2, ABDAY_3, ABDAY_4, ABDAY_5, ABDAY_6, ABDAY_7, ABDAY_1 },
+  { DAY_2, DAY_3, DAY_4, DAY_5, DAY_6, DAY_7, DAY_1 }
+};
+
+static const gint month_item[2][12] =
+{
+  { ABMON_1, ABMON_2, ABMON_3, ABMON_4, ABMON_5, ABMON_6, ABMON_7, ABMON_8, ABMON_9, ABMON_10, ABMON_11, ABMON_12 },
+  { MON_1, MON_2, MON_3, MON_4, MON_5, MON_6, MON_7, MON_8, MON_9, MON_10, MON_11, MON_12 },
+};
+
+#define WEEKDAY_ABBR(d) nl_langinfo (weekday_item[0][g_date_time_get_day_of_week (d) - 1])
+#define WEEKDAY_FULL(d) nl_langinfo (weekday_item[1][g_date_time_get_day_of_week (d) - 1])
+#define MONTH_ABBR(d) nl_langinfo (month_item[0][g_date_time_get_month (d) - 1])
+#define MONTH_FULL(d) nl_langinfo (month_item[1][g_date_time_get_month (d) - 1])
+
+#else
+
 #define GET_AMPM(d)          ((g_date_time_get_hour (d) < 12)  \
                                        /* Translators: 'before midday' indicator */ \
                                 ? C_("GDateTime", "am") \
@@ -175,11 +203,11 @@ static const guint16 days_in_year[2][13] =
 /* Translators: this is the preferred format for expressing the time */
 #define PREFERRED_TIME_FMT C_("GDateTime", "%H:%M:%S")
 
-#define WEEKDAY_ABBR(d)       (get_weekday_name_abbr (g_date_time_get_day_of_week (datetime)))
-#define WEEKDAY_FULL(d)       (get_weekday_name (g_date_time_get_day_of_week (datetime)))
 
-#define MONTH_ABBR(d)         (get_month_name_abbr (g_date_time_get_month (datetime)))
-#define MONTH_FULL(d)         (get_month_name (g_date_time_get_month (datetime)))
+#define WEEKDAY_ABBR(d)       (get_weekday_name_abbr (g_date_time_get_day_of_week (d)))
+#define WEEKDAY_FULL(d)       (get_weekday_name (g_date_time_get_day_of_week (d)))
+#define MONTH_ABBR(d)         (get_month_name_abbr (g_date_time_get_month (d)))
+#define MONTH_FULL(d)         (get_month_name (g_date_time_get_month (d)))
 
 static const gchar *
 get_month_name (gint month)
@@ -309,6 +337,8 @@ get_weekday_name_abbr (gint day)
   return NULL;
 }
 
+#endif  /* HAVE_LANGINFO_TIME */
+
 static inline gint
 ymd_to_days (gint year,
              gint month,