+static int key2val(const struct keyval *mapping, int nmaps, char *key)
+{
+ int i;
+ for (i = 0; i < nmaps; i++)
+ if (!strcmp(mapping[i].s, key)) return mapping[i].v;
+ return -1;
+}
+
+static const char *val2key(const struct keyval *mapping, int nmaps, int val)
+{
+ int i;
+ for (i = 0; i < nmaps; i++)
+ if (mapping[i].v == val) return mapping[i].s;
+ return NULL;
+}
+
+/*
+ * Helper function to parse a comma-separated list of strings into
+ * a preference list array of values. Any missing values are added
+ * to the end and duplicates are weeded.
+ * XXX: assumes vals in 'mapping' are small +ve integers
+ */
+static void gprefs(void *sesskey, char *name, char *def,
+ const struct keyval *mapping, int nvals,
+ int *array)
+{
+ char commalist[80];
+ int n;
+ unsigned long seen = 0; /* bitmap for weeding dups etc */
+ gpps(sesskey, name, def, commalist, sizeof(commalist));
+
+ /* Grotty parsing of commalist. */
+ n = 0;
+ do {
+ int v;
+ char *key;
+ key = strtok(n==0 ? commalist : NULL, ","); /* sorry */
+ if (!key) break;
+ if (((v = key2val(mapping, nvals, key)) != -1) &&
+ !(seen & 1<<v)) {
+ array[n] = v;
+ n++;
+ seen |= 1<<v;
+ }
+ } while (n < nvals);
+ /* Add any missing values (backward compatibility ect). */
+ {
+ int i;
+ for (i = 0; i < nvals; i++) {
+ if (!(seen & 1<<mapping[i].v)) {
+ array[n] = mapping[i].v;
+ n++;
+ }
+ }
+ }
+}
+
+/*
+ * Write out a preference list.
+ */
+static void wprefs(void *sesskey, char *name,
+ const struct keyval *mapping, int nvals,
+ int *array)
+{
+ char buf[80] = ""; /* XXX assumed big enough */
+ int l = sizeof(buf)-1, i;
+ buf[l] = '\0';
+ for (i = 0; l > 0 && i < nvals; i++) {
+ const char *s = val2key(mapping, nvals, array[i]);
+ if (s) {
+ int sl = strlen(s);
+ if (i > 0) {
+ strncat(buf, ",", l);
+ l--;
+ }
+ strncat(buf, s, l);
+ l -= sl;
+ }
+ }
+ write_setting_s(sesskey, name, buf);
+}
+