default resolvers

diff --git a/adns/adns.c b/adns/adns.c
index d8b6e1c35de122693cb7352820d8a0bd56b0186a..e768cd6bf283853c9d74d29fe446410a105d6ca6 100644 (file)
--- a/adns/adns.c
+++ b/adns/adns.c
@@ -50,7 +50,12 @@
  *         -reverse-any ZONE-A-LIKE
  *         -config CONFIG-STRING
  *
+ * adns set-default-resolver RESOLVER
+ *        cancels any outstanding queries from a previous anonymous
+ *        default resolver
+ *
  * adns destroy-resolver RESOLVER
+ *        cancels outstanding queries
  */
 
 #include "tables.h"
@@ -68,6 +73,8 @@ static void asynch_perturbed(Resolver *res);
 
 static void asynch_query_dispose(Tcl_Interp *interp, Query *query);
 
+#define ASSOC_DEFAULTRES "adns-defaultresolver"
+
 /*---------- common resolver/query option processing ----------*/
 
 typedef struct {
@@ -93,7 +100,6 @@ struct OptionInfo {
 };
 
 enum {
-  oisf_makedefault= 0x0001,
   oisf_reverse=     0x0002
 };
 
@@ -117,6 +123,13 @@ static int oifn_reverse_any(Tcl_Interp *ip, const OptionInfo *oi,
 #define OIFS(f) { "-" #f, oifn_fs, 0, oisf_##f, 0 }
 #define OICA(o) { "-" #o, oifn_##o, 1 }
 
+static void optparse_blank(OptionParse *op) {
+  memset(op,0,sizeof(*op));
+  op->errfile= 0;
+  op->errcallback= 0;
+  op->config_string= 0;
+}
+
 static int parse_options(Tcl_Interp *ip, int objc, Tcl_Obj *const *objv,
                         const OptionInfo opttable[], OptionParse *op) {
   const OptionInfo *oi;
@@ -156,8 +169,16 @@ struct Resolver {
   Tcl_TimerToken timertoken;
   int maxfd;
   fd_set handling[3];
+  ScriptToInvoke errcallback;
 };
 
+/* The default resolver is recorded using Tcl_SetAssocData with key
+ * ASSOC_DEFAULTRES to record the Resolver*.  If it was explicitly
+ * created with `adns new-resolver' then ix will be >=0, and the
+ * resolver will be destroyed - leaving no default - when explicitly
+ * requested.  If it was implicitly created (by starting a query when
+ * there is no default) then ix will be -1.  */
+
 static int oifn_errfile(Tcl_Interp *ip, const OptionInfo *oi,
                        Tcl_Obj *arg, OptionParse *op) {
   int rc;
@@ -193,7 +214,6 @@ static const OptionInfo resolver_optioninfos[]= {
   OIFA1(if,noerrprint, adns_if_debug),
   OIFA2(if,checkc,entex),
   OIFA2(if,checkc,freq),
-  OIFS(makedefault),
   OICA(errfile),
   OICA(errcallback),
   OICA(config),
@@ -205,10 +225,17 @@ static void adnslogfn_callback(adns_state ads, void *logfndata,
   abort(); /* fixme implement adns_logcallbackfn */
 }
 
+static Resolver *default_resolver(Tcl_Interp *ip) {
+  return Tcl_GetAssocData(ip,ASSOC_DEFAULTRES,0);
+}
+
 static void destroy_resolver(Tcl_Interp *ip, Resolver *res) {
   void *query_v;
   adns_query aqu;
-  
+ 
+  if (res == default_resolver(ip))
+    Tcl_DeleteAssocData(ip,ASSOC_DEFAULTRES);
+ 
   if (res->ads) {
     /* although adns would throw these away for us, we need to
      * destroy our own data too and only adns has a list of them */
@@ -222,12 +249,14 @@ static void destroy_resolver(Tcl_Interp *ip, Resolver *res) {
   }
   asynch_cancelhandlers(res);
   TFREE(res);
-  /* fixme what about the default resolver */
 }
 
 static void destroy_resolver_idtabcb(Tcl_Interp *ip, void *resolver_v) {
   destroy_resolver(ip,resolver_v);
 }
+static void destroy_resolver_defcb(ClientData resolver_v, Tcl_Interp *ip) {
+  destroy_resolver(ip,resolver_v);
+}
 
 int do_adns_destroy_resolver(ClientData cd, Tcl_Interp *ip, void *res_v) {
   destroy_resolver(ip,res_v);
@@ -235,44 +264,32 @@ int do_adns_destroy_resolver(ClientData cd, Tcl_Interp *ip, void *res_v) {
   return TCL_OK;
 }
 
-int do_adns_new_resolver(ClientData cd, Tcl_Interp *ip,
-                        int objc, Tcl_Obj *const *objv,
-                        void **result) {
-  OptionParse op;
+static int create_resolver(Tcl_Interp *ip, const OptionParse *op,
+                          Resolver **res_r) {
   Resolver *res=0;
   int rc, i, ec;
-
-  op.aflags= adns_if_noautosys;
-  op.sflags= 0;
-  op.errfile= 0;
-  op.errcallback= 0;
-  op.config_string= 0;
-  rc= parse_options(ip,objc,objv,resolver_optioninfos,&op);
-  if (rc) goto x_rc;
-
-  res= TALLOC(sizeof(*res)); assert(res);
+  
+  res= TALLOC(sizeof(*res));  assert(res);
   res->ix= -1;
   res->interp= ip;
   res->ads= 0;
   res->timertoken= 0;
   res->maxfd= 0;
+  scriptinv_init(&res->errcallback);
   for (i=0; i<3; i++) FD_ZERO(&res->handling[i]);
 
-  if (op.aflags & adns_if_noerrprint) {
-    op.errfile= 0;
-    op.errcallback= 0;
-  }
-
-  ec= adns_init_logfn(&res->ads, op.aflags, op.config_string,
-                     op.errcallback ? adnslogfn_callback : 0,
-                     op.errcallback ? (void*)op.errcallback
-                     : (void*)op.errfile);
+  ec= adns_init_logfn(&res->ads,
+                     op->aflags | adns_if_noautosys,
+                     op->config_string,
+                     op->errcallback ? adnslogfn_callback : 0,
+                     op->errcallback ? (void*)op->errcallback
+                     : (void*)op->errfile);
   if (ec) { rc= posixerr(ip,ec,"create adns resolver"); goto x_rc; }
 
-  if (op.errcallback)
-    Tcl_IncrRefCount(op.errcallback);
+  if (op->errcallback)
+    scriptinv_set(&res->errcallback, ip, op->errcallback, 0);
 
-  *result= res;
+  *res_r= res;
   return TCL_OK;
 
  x_rc:
@@ -281,6 +298,36 @@ int do_adns_new_resolver(ClientData cd, Tcl_Interp *ip,
     TFREE(res);
   }
   return rc;
+}  
+
+int do_adns_new_resolver(ClientData cd, Tcl_Interp *ip,
+                        int objc, Tcl_Obj *const *objv,
+                        void **result) {
+  OptionParse op;
+  Resolver *res=0;
+  int rc;
+
+  optparse_blank(&op);
+  rc= parse_options(ip,objc,objv,resolver_optioninfos,&op);
+  if (rc) return rc;
+
+  if (op.aflags & adns_if_noerrprint) {
+    op.errfile= 0;
+    op.errcallback= 0;
+  }
+
+  rc= create_resolver(ip, &op, &res);
+  if (rc) return rc;
+
+  *result= res;
+  return TCL_OK;
+}
+
+int do_adns_set_default_resolver(ClientData cd, Tcl_Interp *ip, void *res_v) {
+  Resolver *res= res_v;
+  Tcl_DeleteAssocData(ip,ASSOC_DEFAULTRES);
+  Tcl_SetAssocData(ip, ASSOC_DEFAULTRES, 0, res);
+  return TCL_OK;
 }
 
 const IdDataSpec adnstcl_resolvers= {
@@ -344,16 +391,29 @@ static int query_submit(Tcl_Interp *ip,
                        adns_query *aqu_r, void *context, OptionParse *op) {
   struct sockaddr sa;
   static const int aftry[]= { AF_INET, AF_INET6 };
+  OptionParse res_op;
   int rc, r, ec;
   adns_state ads;
   
   op->aflags= adns_qf_owner;
   op->sflags= 0;
-  op->resolver= 0; /* fixme default */
+  op->resolver= 0;
   op->reverseany= 0;
   rc= parse_options(ip, queryopts_objc,queryopts_objv, query_optioninfos,op);
   if (rc) return rc;
 
+  if (!op->resolver) {
+    op->resolver= default_resolver(ip);
+    if (!op->resolver) {
+      optparse_blank(&res_op);
+      rc= create_resolver(ip, &res_op, &op->resolver);
+      if (rc) return rc;
+
+      Tcl_SetAssocData(ip, ASSOC_DEFAULTRES,
+                      destroy_resolver_defcb, op->resolver);
+    }
+  }
+  
   if (op->reverseany || (op->sflags & oisf_reverse)) {
     const int *af;
     for (af=aftry; af < af + sizeof(af)/sizeof(*af); af++) {

diff --git a/base/tables-examples.tct b/base/tables-examples.tct
index 98c6cd98cca3118383b2dcf483e4cf1ce01fbbec..8a28c4fe1d13cd11b8c471237bff84dc5cc9bdde 100644 (file)
--- a/base/tables-examples.tct
+++ b/base/tables-examples.tct
@@ -69,6 +69,8 @@ Table adns Adns_SubCommand
        new-resolver
                ...     obj
                =>      iddata(&adnstcl_resolvers)
+       set-default-resolver
+               res     iddata(&adnstcl_resolvers)
        destroy-resolver
                res     iddata(&adnstcl_resolvers)