+ /* The bool{} expansion condition maps a string to boolean.
+ The values supported should match those supported by the ACL condition
+ (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
+ of true/false. Note that Router "condition" rules have a different
+ interpretation, where general data can be used and only a few values
+ map to FALSE.
+ Note that readconf.c boolean matching, for boolean configuration options,
+ only matches true/yes/false/no.
+ The bool_lax{} condition matches the Router logic, which is much more
+ liberal. */
+ case ECOND_BOOL:
+ case ECOND_BOOL_LAX:
+ {
+ uschar *sub_arg[1];
+ uschar *t, *t2;
+ uschar *ourname;
+ size_t len;
+ BOOL boolvalue = FALSE;
+ while (isspace(*s)) s++;
+ if (*s != '{') goto COND_FAILED_CURLY_START;
+ ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
+ switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname))
+ {
+ case 1: expand_string_message = string_sprintf(
+ "too few arguments or bracketing error for %s",
+ ourname);
+ /*FALLTHROUGH*/
+ case 2:
+ case 3: return NULL;
+ }
+ t = sub_arg[0];
+ while (isspace(*t)) t++;
+ len = Ustrlen(t);
+ if (len)
+ {
+ /* trailing whitespace: seems like a good idea to ignore it too */
+ t2 = t + len - 1;
+ while (isspace(*t2)) t2--;
+ if (t2 != (t + len))
+ {
+ *++t2 = '\0';
+ len = t2 - t;
+ }
+ }
+ DEBUG(D_expand)
+ debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
+ /* logic for the lax case from expand_check_condition(), which also does
+ expands, and the logic is both short and stable enough that there should
+ be no maintenance burden from replicating it. */
+ if (len == 0)
+ boolvalue = FALSE;
+ else if (Ustrspn(t, "0123456789") == len)
+ {
+ boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
+ /* expand_check_condition only does a literal string "0" check */
+ if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
+ boolvalue = TRUE;
+ }
+ else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
+ boolvalue = TRUE;
+ else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
+ boolvalue = FALSE;
+ else if (cond_type == ECOND_BOOL_LAX)
+ boolvalue = TRUE;
+ else
+ {
+ expand_string_message = string_sprintf("unrecognised boolean "
+ "value \"%s\"", t);
+ return NULL;
+ }
+ if (yield != NULL) *yield = (boolvalue != 0);
+ return s;
+ }
+