grim/guifications3

implement the preference uri command line and environment variable handling. This hasn't been tested yet, unit tests to come soon.

2009-12-09, Gary Kramlich
c40d12eb29a6
Parents 8f1208fb3b1c
Children 2aead0d89978
implement the preference uri command line and environment variable handling. This hasn't been tested yet, unit tests to come soon.

refs #69
1 files changed, 189 insertions(+), 14 deletions(-)
  • +189 -14
    gflib/gflib/gf_preferences.c
    • --- a/gflib/gflib/gf_preferences.c Wed Dec 09 17:48:51 2009 -0600
    +++ b/gflib/gflib/gf_preferences.c Wed Dec 09 20:23:28 2009 -0600
    @@ -18,38 +18,213 @@
    #include <gflib/gf_preferences.h>
    #include <gflib/gf_filesystem.h>
    +#include <gflib/gf_log.h>
    #include <gflib/gf_preference_engine_null.h>
    #include <gflib/gf_preference_engine_xml.h>
    #include <string.h>
    +#define PREFS_URI_REGEX \
    + "^([A-Za-z][A-Z-a-z0-9]*):((([A-Za-z].*)=(.*))(,([A-Za-z].*)=(.*)))*$"
    +
    /******************************************************************************
    * Globals
    *****************************************************************************/
    static GfPreferenceEngine *root = NULL;
    /******************************************************************************
    + * Helpers
    + *****************************************************************************/
    +static GfPreferenceEngine *
    +gf_preferences_create_default_engine(const gchar *appname) {
    + GfPreferenceEngine *engine = NULL;
    +
    + if(appname) {
    + gchar *gf_dir = NULL, *base = NULL, *filename = NULL;
    +
    + gf_dir = gf_fs_user_settings_dir();
    + base = g_path_get_basename(appname);
    +
    + filename = g_build_filename(gf_dir, base, "prefs.xml", NULL);
    +
    + g_free(gf_dir);
    + g_free(base);
    +
    + engine = gf_preference_engine_xml_new(filename);
    + } else {
    + engine = gf_preference_engine_null_new();
    + }
    +
    + return engine;
    +}
    +
    +/* This big ass basturd takes a uri in the form of:
    + *
    + * GTypeName:GParamName=Value,GParamName,Value
    + *
    + * and creates an object out of it. This might be worth splitting out at some
    + * point. But until then, it's fine where it is. But if it were to be split
    + * out, it should go into gf_object.[ch] and have it's log messages cleaned up.
    + */
    +static GfPreferenceEngine *
    +gf_preferences_create_engine_from_uri(const gchar *uri) {
    + GfPreferenceEngine *engine = NULL;
    + GError *error = NULL;
    + GList *gc = NULL, *l = NULL;
    + GMatchInfo *match_info = NULL;
    + GParameter *params = NULL;
    + GRegex *regex = NULL;
    + GType type = G_TYPE_INVALID;
    + gchar *type_name = NULL;
    + guint n_params = 0;
    + gint matches = 0;
    +
    + regex = g_regex_new(PREFS_URI_REGEX, 0, 0, &error);
    +
    + if(!g_regex_match(regex, uri, 0, &match_info)) {
    + g_regex_unref(regex);
    +
    + gf_log_warning("GfPreferences",
    + "Could not parse preference uri: '%s'\n"
    + "Falling back to the default preference engine.\n",
    + uri);
    +
    + return NULL;
    + }
    +
    + /* we have the match_info now, so kill the regex */
    + g_regex_unref(regex);
    +
    + /* the type name is in position 1, so grab it and see if the type even
    + * exists.
    + */
    + type_name = g_match_info_fetch(match_info, 1);
    + type = g_type_from_name(type_name);
    +
    + if(type == G_TYPE_INVALID) {
    + g_match_info_free(match_info);
    +
    + gf_log_warning("GfPreferences",
    + "Could not find the type information for preference "
    + "engine '%s'\n"
    + "Falling back to the default preference engine.\n",
    + type_name);
    +
    + g_free(type_name);
    +
    + return NULL;
    + }
    +
    + /* now dig through the given params and build the GParameterArray */
    + if((matches = g_match_info_get_match_count(match_info)) > 1) {
    + GObjectClass *klass = g_type_class_ref(type);
    + guint cur = 0;
    +
    + /* we ignore the first two matches (the engine and the full param
    + * string. Then our params are grouped in threes: name=value, name,
    + * and value. So our number of params is (matches - 2) / 3
    + */
    + n_params = (guint)((matches - 2) / 3);
    +
    + /* now allocate params */
    + params = g_new0(GParameter, n_params + 1);
    +
    + for(cur = 0; cur < n_params; cur++) {
    + GParamSpec *pspec = NULL;
    + gchar *name = NULL, *value = NULL;
    + gint index = 0;
    +
    + /* we multiple by 3 to get to the group, and add two to actually
    + * get to the data.
    + */
    + index = (cur * 3) + 2;
    +
    + /* grab the name and see if the parameter exists and that we can
    + * handle it's type. If we can't do either, log a warning and
    + * continue on.
    + */
    + name = g_match_info_fetch(match_info, index + 1);
    + pspec = g_object_class_find_property(klass, name);
    +
    + if(!pspec) {
    + gf_log_warning("GfPreferences",
    + "Preference engine %s does not have a property "
    + "named '%s'.\n",
    + type_name, name);
    +
    + g_free(name);
    +
    + continue;
    + }
    +
    + switch(pspec->value_type) {
    + case G_TYPE_STRING:
    + break;
    + default:
    + gf_log_warning("GfPreference",
    + "Don't know how to handle property '%s' "
    + "with type '%s' for engine '%s'.\n",
    + name, g_type_name(pspec->value_type),
    + type_name);
    +
    + g_free(name);
    +
    + continue;
    + }
    +
    + /* we know the property exists now, so set it in the GParameter and
    + * add the name to gc
    + */
    + params[cur].name = name;
    + gc = g_list_prepend(gc, name);
    +
    + /* set the GValue in the GParameter */
    + value = g_match_info_fetch(match_info, index + 2);
    +
    + g_value_init(&params[cur].value, G_TYPE_STRING);
    + g_value_take_string(&params[cur].value, value);
    + }
    +
    + g_type_class_unref(klass);
    + }
    +
    + engine = g_object_newv(type, n_params, params);
    +
    + /* cleanup time! */
    + for(l = gc; l; l = l->next)
    + g_free(l->data);
    + g_list_free(gc);
    +
    + g_match_info_free(match_info);
    +
    + /* we free the type_name down here so we can use it in the error messages
    + * during all the fun above.
    + */
    + g_free(type_name);
    +
    + return engine;
    +}
    +
    +/******************************************************************************
    * Private API
    *****************************************************************************/
    void
    gf_preferences_init(const gchar *appname, const gchar *uri) {
    - if(!uri) {
    - if(appname) {
    - gchar *gf_dir = NULL, *base = NULL, *filename = NULL;
    + GfPreferenceEngine *engine = NULL;
    + const gchar *real_uri = NULL;
    - gf_dir = gf_fs_user_settings_dir();
    - base = g_path_get_basename(appname);
    -
    - filename = g_build_filename(gf_dir, base, "prefs.xml", NULL);
    + /* if the uri was given on the command line, use it. Otherwise, try the
    + * environment variable.
    + */
    + real_uri = (uri) ? uri : g_getenv("GF_PREFS_URI");
    - g_free(gf_dir);
    - g_free(base);
    + if(real_uri)
    + engine = gf_preferences_create_engine_from_uri(real_uri);
    - root = gf_preference_engine_xml_new(filename);
    - } else {
    - root = gf_preference_engine_null_new();
    - }
    - }
    + if(!engine)
    + engine = gf_preferences_create_default_engine(appname);
    +
    + root = engine;
    }
    void