Add the support of cpdb-libs for groups and translations

- Using general message string catalogs from CUPS and also message string catalogs from individual print queues.
- Message catalog management done by libcupsfilters 2.x, via the `cfCatalog...()` API functions (`catalog.h`).
- Option group support
- Log messages handled by frontend library

Author: TinyTrebuchet

configure.ac

@@ -14,12 +14,13 @@ AC_PROG_CC
 
 # Checks for backend library 
 PKG_CHECK_MODULES([CPDB],[cpdb >= 2])
+PKG_CHECK_MODULES([LIBCUPSFILTERS], [libcupsfilters >= 2])
 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 cups/cups.h])
+AC_CHECK_HEADERS([stdlib.h string.h cups/cups.h cupsfilters/catalog.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_SIZE_T

src/Makefile.am

@@ -2,12 +2,14 @@ backenddir = $(CPDB_BACKEND_DIR)
 backend_PROGRAMS = cups
 cups_SOURCES = print_backend_cups.c backend_helper.c backend_helper.h
 cups_CPPFLAGS  = $(CPDB_CFLAGS)
+cups_CPPFLAGS += $(LIBCUPSFILTERS_CFLAGS)
 cups_CPPFLAGS += $(GLIB_CFLAGS)
 cups_CPPFLAGS += $(GIO_CFLAGS)
 cups_CPPFLAGS += $(GIOUNIX_CFLAGS)
 
-cups_LDADD  =  $(CPDB_LIBS)
-cups_LDADD += -lcups -lpthread -lm -lcrypt
+cups_LDADD  = -lcups -lpthread -lm -lcrypt
+cups_LDADD += $(CPDB_LIBS)
+cups_LDADD += $(LIBCUPSFILTERS_LIBS)
 cups_LDADD += $(GLIB_LIBS)
 cups_LDADD += $(GIO_LIBS)
 cups_LDADD += $(GIOUNIX_LIBS)

src/backend_helper.c

@@ -584,13 +584,16 @@ void unpack_option_array(GVariant *var, int num_options, Option **options)
 }
 GVariant *pack_option(const Option *opt)
 {
-    GVariant **t = g_new(GVariant *, 4);
+    char *group_name = cpdbGetGroup(opt->option_name);
+    GVariant **t = g_new(GVariant *, 5);
     t[0] = g_variant_new_string(opt->option_name);
-    t[1] = g_variant_new_string(opt->default_value); //("s", cpdbGetStringCopy(opt->default_value));
-    t[2] = g_variant_new_int32(opt->num_supported);
-    t[3] = cpdbPackStringArray(opt->num_supported, opt->supported_values);
-    GVariant *tuple_variant = g_variant_new_tuple(t, 4);
+    t[1] = g_variant_new_string(group_name);
+    t[2] = g_variant_new_string(opt->default_value);
+    t[3] = g_variant_new_int32(opt->num_supported);
+    t[4] = cpdbPackStringArray(opt->num_supported, opt->supported_values);
+    GVariant *tuple_variant = g_variant_new_tuple(t, 5);
     g_free(t);
+    free(group_name);
     return tuple_variant;
 }
 GVariant *pack_media(const Media *media)
@@ -1594,6 +1597,97 @@ void print_job(cups_job_t *j)
     printf("state : %s\n", state);
 }
 
+char *get_option_translation(PrinterCUPS *p,
+                             const char *option_name,
+                             const char *locale)
+{
+    char *copy;
+    const char *uri, *translation;
+    static const char *const req_attrs[] = {"printer-strings-uri"};
+    ipp_attribute_t *attr;
+    ipp_t *request, *response;
+    cups_array_t *opts_catalog, *printer_opts_catalog;
+
+    ensure_printer_connection(p);
+    request = ippNewRequest(IPP_OP_GET_PRINTER_ATTRIBUTES);
+    uri = cupsGetOption("printer-uri-supported", 
+                        p->dest->num_options,
+                        p->dest->options);
+    ippAddString(request, IPP_TAG_OPERATION, IPP_TAG_URI,
+                    "printer-uri", NULL, uri);
+    ippAddStrings(request, IPP_TAG_OPERATION, IPP_TAG_KEYWORD,
+                    "requested-attributes", 1, NULL, req_attrs);
+    response = cupsDoRequest(p->http, request, "/");
+    if (cupsLastError() >= IPP_STATUS_ERROR_BAD_REQUEST)
+    {
+        /* request failed */
+        printf("Request failed: %s\n", cupsLastErrorString());
+        return cpdbGetStringCopy(option_name);
+    }
+
+    opts_catalog = cfCatalogOptionArrayNew();
+    cfCatalogLoad(NULL, locale, opts_catalog);
+    if ((attr = ippFindAttribute(response, "printer-strings-uri",
+                                    IPP_TAG_URI)) != NULL)
+    {
+        printer_opts_catalog = cfCatalogOptionArrayNew();
+        cfCatalogLoad(ippGetString(attr, 0, NULL), NULL, printer_opts_catalog);
+    }
+
+    translation = cfCatalogLookUpOption((char *)option_name, 
+                                        opts_catalog, printer_opts_catalog);
+    copy = cpdbGetStringCopy(translation);
+    cupsArrayDelete(opts_catalog);
+    cupsArrayDelete(printer_opts_catalog);
+    return copy;
+}
+
+char *get_choice_translation(PrinterCUPS *p,
+                             const char *option_name,
+                             const char *choice_name,
+                             const char *locale)
+{
+    char *copy;
+    const char *uri, *translation;
+    static const char *const req_attrs[] = {"printer-strings-uri"};
+    ipp_attribute_t *attr;
+    ipp_t *request, *response;
+    cups_array_t *opts_catalog, *printer_opts_catalog;
+
+    ensure_printer_connection(p);
+    request = ippNewRequest(IPP_OP_GET_PRINTER_ATTRIBUTES);
+    uri = cupsGetOption("printer-uri-supported", 
+                        p->dest->num_options,
+                        p->dest->options);
+    ippAddString(request, IPP_TAG_OPERATION, IPP_TAG_URI,
+                    "printer-uri", NULL, uri);
+    ippAddStrings(request, IPP_TAG_OPERATION, IPP_TAG_KEYWORD,
+                    "requested-attributes", 1, NULL, req_attrs);
+    response = cupsDoRequest(p->http, request, "/");
+    if (cupsLastError() >= IPP_STATUS_ERROR_BAD_REQUEST)
+    {
+        /* request failed */
+        printf("Request failed: %s\n", cupsLastErrorString());
+        return cpdbGetStringCopy(choice_name);
+    }
+
+    opts_catalog = cfCatalogOptionArrayNew();
+    cfCatalogLoad(NULL, locale, opts_catalog);
+    if ((attr = ippFindAttribute(response, "printer-strings-uri",
+                                    IPP_TAG_URI)) != NULL)
+    {
+        printer_opts_catalog = cfCatalogOptionArrayNew();
+        cfCatalogLoad(ippGetString(attr, 0, NULL), NULL, printer_opts_catalog);
+    }
+
+    translation = cfCatalogLookUpChoice((char *)choice_name, (char *)option_name,
+                                        opts_catalog, printer_opts_catalog);
+    copy = cpdbGetStringCopy(translation);
+    cupsArrayDelete(opts_catalog);
+    cupsArrayDelete(printer_opts_catalog);
+    return copy;
+}
+
 char *get_human_readable_option_name(const char *option_name)
 {
     if (strcmp("page-set", option_name) == 0)

src/backend_helper.h

@@ -5,9 +5,12 @@
 #include <stdlib.h>
 #include <glib.h>
 #include <string.h>
+
 #include <cups/cups.h>
 #include <cups/ppd.h>
-#include <cpdb/cpdb.h>
+#include <cupsfilters/catalog.h>
+
+#include <cpdb/backend.h>
 
 #define INFO 3
 #define WARN 2
@@ -201,6 +204,18 @@ int print_file(PrinterCUPS *p, const char *file_path, int num_settings, GVariant
 int get_active_jobs_count(PrinterCUPS *p);
 gboolean cancel_job(PrinterCUPS *p, int jobid);
 
+/**
+ * Get translation of choice name for a given locale
+ */
+char *get_option_translation(PrinterCUPS *p, const char *option_name,
+                             const char *locale);
+
+/**
+ * Get translation of option name for a given locale
+ */
+char *get_choice_translation(PrinterCUPS *p, const char *option_name,
+                             const char *choice_name, const char *locale);
+
 /**
  * Get human readable names of the options.
  */

src/print_backend_cups.c

@@ -2,8 +2,10 @@
 #include <stdlib.h>
 #include <glib.h>
 #include <string.h>
+
 #include <cups/cups.h>
-#include <cpdb/cpdb.h>
+
+#include <cpdb/backend.h>
 #include "backend_helper.h"
 
 #define _CUPS_NO_DEPRECATED 1
@@ -27,6 +29,7 @@ int main()
     int p = ippPort();
 
     b = get_new_BackendObj();
+    cpdbInit();
     acquire_session_bus_name(BUS_NAME);
     GMainLoop *loop = g_main_loop_new(NULL, FALSE);
     g_main_loop_run(loop);
@@ -244,6 +247,53 @@ static gboolean on_handle_get_printer_state(PrintBackend *interface,
     return TRUE;
 }
 
+static gboolean on_handle_get_option_translation(PrintBackend *interface,
+                                                 GDBusMethodInvocation *invocation,
+                                                 const gchar *printer_name,
+                                                 const gchar *option_name,
+                                                 const gchar *locale,
+                                                 gpointer user_data)
+{
+    const char *dialog_name = g_dbus_method_invocation_get_sender(invocation); /// potential risk
+    PrinterCUPS *p = get_printer_by_name(b, dialog_name, printer_name);
+    char *translation = get_option_translation(p, option_name, locale);
+    if (translation == NULL)
+        translation = cpdbGetStringCopy(option_name);
+    print_backend_complete_get_option_translation(interface, invocation, translation);
+    return TRUE;
+}
+
+static gboolean on_handle_get_choice_translation(PrintBackend *interface,
+                                                 GDBusMethodInvocation *invocation,
+                                                 const gchar *printer_name,
+                                                 const gchar *option_name,
+                                                 const gchar *choice_name,
+                                                 const gchar *locale,
+                                                 gpointer user_data)
+{
+    const char *dialog_name = g_dbus_method_invocation_get_sender(invocation); /// potential risk
+    PrinterCUPS *p = get_printer_by_name(b, dialog_name, printer_name);
+    char *translation = get_choice_translation(p, option_name,
+                                                choice_name, locale);
+    if (translation == NULL)
+        translation = cpdbGetStringCopy(choice_name);
+    print_backend_complete_get_choice_translation(interface, invocation, translation);
+    return TRUE;
+}
+
+static gboolean on_handle_get_group_translation(PrintBackend *interface,
+                                                GDBusMethodInvocation *invocation,
+                                                const gchar *printer_name,
+                                                const gchar *group_name,
+                                                const gchar *locale,
+                                                gpointer user_data)
+{
+    char *translation = cpdbGetGroupTranslation2(group_name, locale);
+    print_backend_complete_get_group_translation(interface, invocation, translation);
+    free(translation);
+    return TRUE;
+}
+
 static gboolean on_handle_get_human_readable_option_name(PrintBackend *interface,
                                                          GDBusMethodInvocation *invocation,
                                                          const gchar *option_name,
@@ -336,7 +386,7 @@ static gboolean on_handle_get_all_options(PrintBackend *interface,
     int count = get_all_options(p, &options);
     count = add_media_to_options(p, medias, media_count, &options, count);
     GVariant *variant;
-    builder = g_variant_builder_new(G_VARIANT_TYPE("a(ssia(s))"));
+    builder = g_variant_builder_new(G_VARIANT_TYPE("a(sssia(s))"));
 
     for (int i = 0; i < count; i++)
     {
@@ -473,6 +523,18 @@ void connect_to_signals()
                      "handle-replace",              //signal name
                      G_CALLBACK(on_handle_replace), //callback
                      NULL);
+    g_signal_connect(skeleton,                                      //instance
+                     "handle-get-option-translation",               //signal name
+                     G_CALLBACK(on_handle_get_option_translation),  //callback
+                     NULL);
+    g_signal_connect(skeleton,                                      //instance
+                     "handle-get-choice-translation",               //signal name
+                     G_CALLBACK(on_handle_get_choice_translation),  //callback
+                     NULL);
+    g_signal_connect(skeleton,                                      //instance
+                     "handle-get-group-translation",                //signal name
+                     G_CALLBACK(on_handle_get_group_translation),   //callback
+                     NULL);
     g_signal_connect(skeleton,                                             //instance
                      "handle-get-human-readable-option-name",              //signal name
                      G_CALLBACK(on_handle_get_human_readable_option_name), //callback