Add option groups, translation support and frontend/backend debug logging

- Options groups: To allow better structuring of options in print dialogs, common options are categorized in groups, like media, print quality, color, finishing, ... This can be primarily done by the backends but the frontend library can do fallback/default assignments for options not assigned by the backend.
- Translation support: Translations of option, choice, and group names are now supported, not only English human-readable strings. And Translations can be provided by the backends (also polling them from the print service) and by the frontend library.
- Debug logging: Now backends forward their log messages to the frontend library for easier debugging.

Author: TinyTrebuchet

.gitignore

@@ -11,6 +11,11 @@ autoscan.log
 aclocal.m4
 autom4te.cache
 build-aux/
+m4/*
+!m4/cpdb*
+po/*
+!po/POTFILE.in
+!po/Makevars
 config.*
 configure
 libtool

Makefile.am

@@ -1,7 +1,7 @@
-EXTRA_DIST = demo/*.c demo/Makefile README.md LICENSE.md COPYING CHANGES.md autogen.sh
+EXTRA_DIST = m4/ChangeLog  demo/*.c demo/Makefile README.md LICENSE.md COPYING CHANGES.md autogen.sh
 AUTOMAKE_OPTIONS = foreign
-SUBDIRS = cpdb
-#ACLOCAL_AMFLAGS = '-I m4'
+ACLOCAL_AMFLAGS = -I m4
+SUBDIRS = cpdb po
 
 pkgconfigdir = $(libdir)/pkgconfig
 pkgconfig_DATA = cpdb-backend.pc cpdb-frontend.pc cpdb.pc

README.md

@@ -12,14 +12,13 @@ If one opens the print dialog, the dialog will not talk directly to CUPS, a clou
 
 ## Dependencies
 
- - GLIB 2.0:
-   `sudo apt install libglib2.0-dev`
-   
- - LIBDBUS:
-   `sudo apt install libdbus-1-dev`
-
- - LIBTOOL:
-   `sudo apt install libtool`
+ - GLIB 2.0
+ - LIBDBUS
+ - LIBTOOL
+ - GETTEXT
+
+On Debian based distros, these can be installed by running: \
+`sudo apt install libglib2.0-dev libdbus-1-dev libtool gettext`
 
 ## Build and installation
 

autogen.sh

@@ -1,2 +1,3 @@
 mkdir -p build-aux \
+&& gettextize --no-changelog \
 && autoreconf -fi

configure.ac

@@ -1,47 +1,29 @@
 #                                               -*- Autoconf -*- 
 # Process this file with autoconf to produce a configure script. 
 
-AC_PREREQ([2.69]) 
+AC_PREREQ([2.69])
+
+dnl Package name and version...
 AC_INIT([cpdb-libs], [2.0b1], [https://github.com/OpenPrinting/cpdb-libs/issues], [cpdb-libs], [https://github.com/OpenPrinting/cpdb-libs])
-AC_CONFIG_AUX_DIR([build-aux])
-AC_CONFIG_SRCDIR([cpdb/cpdb-frontend.h])
-AM_INIT_AUTOMAKE([-Wall foreign])
 
-: ${CFLAGS=""}
+AC_CONFIG_SRCDIR([cpdb/cpdb-frontend.h])
 
-# Check for a C compiler 
-AC_PROG_CC 
+AC_CONFIG_MACRO_DIRS([m4])
+AC_CONFIG_AUX_DIR([build-aux])
+AM_INIT_AUTOMAKE([-Wall foreign])
 
-#Check for archiver
+# Check for archiver
 AM_PROG_AR
 
-LT_INIT
+# Check for GNU gettext
+AM_GNU_GETTEXT([external])
+AM_GNU_GETTEXT_VERSION([0.21])
 
-PKG_CHECK_MODULES([GIO],[gio-2.0]) 
-PKG_CHECK_MODULES([GIOUNIX],[gio-unix-2.0]) 
-PKG_CHECK_MODULES([GLIB],[glib-2.0]) 
-
-# Checks for header files. 
-AC_CHECK_HEADERS([stdlib.h string.h unistd.h sys/stat.h]) 
- 
-# Checks for typedefs, structures, and compiler characteristics. 
-AC_TYPE_SIZE_T 
- 
-# Checks for library functions.
-AC_FUNC_MALLOC
-AC_CHECK_FUNCS([access getcwd mkdir])
-
-# The info directory which will be read by the frontend
-CPDB_BACKEND_INFO_DIR="$datadir/print-backends"
-AC_SUBST([CPDB_BACKEND_INFO_DIR])
-
-# The directory for the backend executables
-CPDB_BACKEND_EXEC_DIR="$libdir/print-backends"
-AC_SUBST([CPDB_BACKEND_EXEC_DIR])
+LT_INIT
 
-# The directory for system wide config files
-CPDB_SYSCONFDIR="$sysconfdir"
-AC_SUBST([CPDB_SYSCONFDIR])
+dnl Include configure tests for different areas...
+sinclude(m4/cpdb-directories.m4)
+sinclude(m4/cpdb-common.m4)
 
 AC_CONFIG_FILES([Makefile
                  cpdb/Makefile
@@ -50,3 +32,6 @@ AC_CONFIG_FILES([Makefile
                  cpdb.pc])
 
 AC_OUTPUT
+
+dnl Make sure m4 scripts are executable
+chmod +x m4

cpdb/Makefile.am

@@ -14,7 +14,6 @@ libcpdb_la_CPPFLAGS  = $(GLIB_CFLAGS)
 libcpdb_la_CPPFLAGS += $(GIO_CFLAGS)
 libcpdb_la_CPPFLAGS += $(GIOUNIX_CFLAGS)
 libcpdb_la_CPPFLAGS += -I..
-libcpdb_la_CPPFLAGS += -DCPDB_SYSCONFDIR=\"@CPDB_SYSCONFDIR@\"
 
 libcpdb_la_LIBADD  = $(GLIB_LIBS)
 libcpdb_la_LIBADD += $(GIO_LIBS)
@@ -30,7 +29,6 @@ libcpdb_frontend_la_CPPFLAGS  = $(GLIB_CFLAGS)
 libcpdb_frontend_la_CPPFLAGS += $(GIO_CFLAGS)
 libcpdb_frontend_la_CPPFLAGS += $(GIOUNIX_CFLAGS)
 libcpdb_frontend_la_CPPFLAGS += -I..
-libcpdb_frontend_la_CPPFLAGS += -DCPDB_BACKEND_INFO_DIR=\"@CPDB_BACKEND_INFO_DIR@\"
 
 libcpdb_frontend_la_LIBADD  = -lpthread -lm -lcrypt
 libcpdb_frontend_la_LIBADD += $(GLIB_LIBS)