tag: add some utility functions for language codes and tags

Add some utility functions for language tags and ISO-639
codes. These are useful for both GUIs and elements. The
iso-codes package is used for language name translations
if available.

API: gst_tag_get_language_codes()
API: gst_tag_get_language_name()
API: gst_tag_get_language_code()
API: gst_tag_get_language_code_iso_639_1()
API: gst_tag_get_language_code_iso_639_2B()
API: gst_tag_get_language_code_iso_639_2T()

.gitignore

@@ -42,3 +42,5 @@ Makefile.in
 Makefile
 *.gir
 *.typelib
+
+gst-libs/gst/tag/mklangtables

configure.ac

@@ -348,6 +348,56 @@ if test "x$HAVE_SYS_SOCKET_H" != "xyes"; then
   AG_GST_DISABLE_PLUGIN(tcp)
 fi
 
+dnl iso-codes is optional, used by libgsttag
+AC_ARG_ENABLE(iso-codes,
+AC_HELP_STRING([--enable-iso-codes],[use iso-codes if installed]),
+[case "${enableval}" in
+  yes) enable_iso_codes=yes ;;
+  no)  enable_iso_codes=no ;;
+  *) AC_MSG_ERROR(bad value ${enableval} for --enable-iso-codes) ;;
+esac
+],
+[enable_iso_codes=yes]) dnl Default value
+
+AC_MSG_CHECKING([whether to use iso-codes if they are available])
+if test "x$enable_iso_codes" = "xyes"; then
+  AC_MSG_RESULT([yes])
+  have_iso_codes=no
+  AC_MSG_CHECKING([whether iso-codes are available on this system])
+  if $PKG_CONFIG iso-codes; then
+    AC_MSG_RESULT([yes])
+    AC_MSG_CHECKING([whether iso-codes has iso-639 domain])
+    if $PKG_CONFIG --variable=domains iso-codes | $GREP -q 639 ; then
+      AC_MSG_RESULT([yes])
+      AC_MSG_CHECKING([for iso-codes prefix])
+      ISO_CODES_PREFIX=`$PKG_CONFIG --variable=prefix iso-codes`
+      if test -d "$ISO_CODES_PREFIX"; then
+        AC_MSG_RESULT([yes])
+        AC_MSG_CHECKING([ISO_CODES_PREFIX])
+        AC_MSG_RESULT([$ISO_CODES_PREFIX])
+        ISO_639_DOMAIN="iso_639"
+        AC_MSG_CHECKING([ISO_639_DOMAIN])
+        AC_MSG_RESULT([$ISO_639_DOMAIN])
+        have_iso_codes=yes
+        AC_DEFINE([HAVE_ISO_CODES], [1], [make use of iso-codes for ISO-639])
+        AC_DEFINE_UNQUOTED([ISO_CODES_PREFIX], ["$ISO_CODES_PREFIX"], [prefix])
+        ISO_CODES_VERSION=`$PKG_CONFIG --modversion iso-codes`
+        AC_DEFINE_UNQUOTED([ISO_CODES_VERSION], ["$ISO_CODES_VERSION"], [ ])
+      else
+        AC_MSG_RESULT([no])
+      fi
+    else
+      AC_MSG_RESULT([no])
+    fi
+  else
+    AC_MSG_RESULT([no])
+  fi
+  AM_CONDITIONAL(USE_ISO_CODES, test "x$have_iso_codes" = "xyes")
+else
+  AC_MSG_RESULT([no (disabled via --disable-iso-codes)])
+  AM_CONDITIONAL(USE_ISO_CODES, false)
+fi
+
 dnl *** sys plug-ins ***
 
 echo
@@ -847,6 +897,7 @@ sed \
     -e 's/.* HAVE_CPU_I386$/#define HAVE_CPU_I386 1/' \
     -e 's/.* HAVE_FGETPOS$/#define HAVE_FGETPOS 1/' \
     -e 's/.* HAVE_FSETPOS$/#define HAVE_FSETPOS 1/' \
+    -e 's/.* HAVE_ISO_CODES$/#undef HAVE_ISO_CODES/' \
     -e 's/.* HAVE_LIBXML2$/#define HAVE_LIBXML2 1/' \
     -e 's/.* HAVE_PROCESS_H$/#define HAVE_PROCESS_H 1/' \
     -e 's/.* HAVE_STDLIB_H$/#define HAVE_STDLIB_H 1/' \
@@ -856,6 +907,8 @@ sed \
     -e 's/.* HAVE_WIN32$/#define HAVE_WIN32 1/' \
     -e 's/.* HAVE_WINSOCK2_H$/#define HAVE_WINSOCK2_H 1/' \
     -e 's/.* HOST_CPU$/#define HOST_CPU "i686"/' \
+    -e 's/.* ISO_CODES_PREFIX$/#undef ISO_CODES_PREFIX/' \
+    -e 's/.* ISO_CODES_VERSION$/#undef ISO_CODES_VERSION/' \
     -e 's/.* LIBDIR$/#ifdef _DEBUG\n#  define LIBDIR PREFIX "\\\\debug\\\\lib"\n#else\n#  define LIBDIR PREFIX "\\\\lib"\n#endif/' \
     -e 's/.* LOCALEDIR$/#define LOCALEDIR PREFIX "\\\\share\\\\locale"/' \
     -e "s/.* PACKAGE$/#define PACKAGE \"$PACKAGE\"/" \

docs/libs/gst-plugins-base-libs-docs.sgml

@@ -192,6 +192,7 @@
       <xi:include href="xml/gsttagvorbis.xml" />
       <xi:include href="xml/gsttagid3.xml" />
       <xi:include href="xml/gsttagdemux.xml" />
+      <xi:include href="xml/gsttaglanguagecodes.xml" />
     </chapter>
 
     <chapter id="gstreamer-base-utils">

docs/libs/gst-plugins-base-libs-sections.txt

@@ -1564,6 +1564,18 @@ GstTagDemuxClass
 GstTagDemuxResult
 </SECTION>
 
+<SECTION>
+<FILE>gsttaglanguagecodes</FILE>
+<INCLUDE>gst/tag/tag.h</INCLUDE>
+<SUBSECTION>
+gst_tag_get_language_codes
+gst_tag_get_language_name
+gst_tag_get_language_code
+gst_tag_get_language_code_iso_639_1
+gst_tag_get_language_code_iso_639_2B
+gst_tag_get_language_code_iso_639_2T
+</SECTION>
+
 # base utils
 
 <SECTION>

gst-libs/gst/tag/Makefile.am

@@ -6,7 +6,7 @@ libgsttaginclude_HEADERS = \
 
 lib_LTLIBRARIES = libgsttag-@GST_MAJORMINOR@.la
 
-libgsttag_@GST_MAJORMINOR@_la_SOURCES = gstvorbistag.c gstid3tag.c tags.c gsttagdemux.c
+libgsttag_@GST_MAJORMINOR@_la_SOURCES = gstvorbistag.c gstid3tag.c lang.c tags.c gsttagdemux.c
 libgsttag_@GST_MAJORMINOR@_la_CFLAGS = $(GST_PLUGINS_BASE_CFLAGS) $(GST_BASE_CFLAGS) $(GST_CFLAGS)
 libgsttag_@GST_MAJORMINOR@_la_LIBADD = $(GST_BASE_LIBS) $(GST_LIBS) 
 libgsttag_@GST_MAJORMINOR@_la_LDFLAGS = $(GST_LIB_LDFLAGS) $(GST_ALL_LDFLAGS) $(GST_LT_LDFLAGS)
@@ -49,3 +49,17 @@ typelibs_DATA = $(BUILT_GIRSOURCES:.gir=.typelib)
 
 CLEANFILES = $(BUILT_GIRSOURCES) $(typelibs_DATA)
 endif
+
+# little program that reads iso_639.xml and outputs tables for us as fallback
+# for when iso-codes are not available (and so we don't have to read the xml
+# just to map codes)
+if USE_ISO_CODES
+ISO_CODE_PROGS = mklangtables
+mklangtables_SOURCES = mklangtables.c
+mklangtables_CFLAGS = $(GST_CFLAGS)
+mklangtables_LDADD = $(GST_LIBS)
+else
+ISO_CODE_PROGS =
+endif
+
+noinst_PROGRAMS = $(ISO_CODE_PROGS)