X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=chiark-tcl.git;a=blobdiff_plain;f=adns%2Fadns.c;h=d57c49bf1ba3e2efee7f11add33135a8e450e671;hp=1ecb6729c19b635e343554beec29ee1211fc1c86;hb=79afa3a523e92a1d552d46729b1e1d04db97f72c;hpb=9b2c18cc9d122b45f9e737864921d32baa599f0c

diff --git a/adns/adns.c b/adns/adns.c
index 1ecb672..d57c49b 100644
--- a/adns/adns.c
+++ b/adns/adns.c
@@ -37,6 +37,8 @@
  *         -quotefail-cname
  *         -cname-loose
  *         -cname-forbid
+ *         -reverse
+ *         -reverse-any ZONE-A-LIKE
  *
  * adns new-resolver [RES-OPTIONS...]                         => RESOLVER
  *        options:
@@ -46,13 +48,20 @@
  *         -noenv|-debug|-logpid
  *         -checkc-entex
  *         -checkc-freq
- *         -reverse
- *         -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
  */
 
+#define _GNU_SOURCE
+
+#include <stdio.h>
+
 #include "tables.h"
 #include "hbytes.h"
 
@@ -61,10 +70,15 @@
 typedef struct Query Query;
 typedef struct Resolver Resolver;
 typedef struct OptionInfo OptionInfo;
-static void asynch_check(Resolver *res);
-static void asynch_sethandlers(Resolver *res, int shutdown);
+
+static void asynch_sethandlers(Resolver *res);
+static void asynch_cancelhandlers(Resolver *res);
+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 {
@@ -90,7 +104,6 @@ struct OptionInfo {
 };
 
 enum {
-  oisf_makedefault= 0x0001,
   oisf_reverse=     0x0002
 };
 
@@ -114,6 +127,13 @@ 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= stderr;
+  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;
@@ -153,8 +173,17 @@ struct Resolver {
   Tcl_TimerToken timertoken;
   int maxfd;
   fd_set handling[3];
+  ScriptToInvoke errcallback;
+  Tcl_Obj *errstring_accum;
 };
 
+/* 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;
@@ -190,22 +219,64 @@ 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),
   { 0 }
 };
 
+static void adnslogfn_flushmessage(Resolver *res) {
+  scriptinv_invoke(&res->errcallback, 1, &res->errstring_accum);
+  Tcl_SetObjLength(res->errstring_accum, 0);
+}
+
 static void adnslogfn_callback(adns_state ads, void *logfndata,
 			       const char *fmt, va_list al) {
-  abort(); /* fixme implement adns_logcallbackfn */
+  Resolver *res= logfndata;
+  int l, newline;
+  char *str;
+
+  l= vasprintf(&str,fmt,al);
+  if (l<0) {
+    posixerr(res->interp,errno,"construct adns log callback string");
+    Tcl_BackgroundError(res->interp);
+  }
+
+  if (l==0) { free(str); return; }
+  if ((newline= l>0 && str[l-1]=='\n')) l--;
+
+  if (!res->errstring_accum) {
+    res->errstring_accum= Tcl_NewStringObj(str,l);
+    Tcl_IncrRefCount(res->errstring_accum);
+  } else {
+    Tcl_AppendToObj(res->errstring_accum,str,l);
+  }
+  free(str);
+
+  if (newline)
+    adnslogfn_flushmessage(res);
+}
+
+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;
+  int logstring_len;
+  char *rstr;
   adns_query aqu;
-  
+ 
+  if (res == default_resolver(ip))
+    Tcl_DeleteAssocData(ip,ASSOC_DEFAULTRES);
+ 
+  if (res->errstring_accum) {
+    rstr= Tcl_GetStringFromObj(res->errstring_accum, &logstring_len);
+    assert(rstr);
+    if (logstring_len)
+      adnslogfn_flushmessage(res);
+  }
+
   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 */
@@ -216,60 +287,52 @@ static void destroy_resolver(Tcl_Interp *ip, Resolver *res) {
       asynch_query_dispose(ip, query_v);
     }
     adns_finish(res->ads);
+    res->ads= 0;
   }
-  asynch_sethandlers(res,1);
-  TFREE(res);
-  /* fixme what about the default resolver */
+  asynch_cancelhandlers(res);
+  scriptinv_cancel(&res->errcallback);
+  Tcl_EventuallyFree(res, Tcl_Free);
 }
 
 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);
   tabledataid_disposing(ip,res_v,&adnstcl_resolvers);
+  destroy_resolver(ip,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;
   for (i=0; i<3; i++) FD_ZERO(&res->handling[i]);
+  scriptinv_init(&res->errcallback);
+  res->errstring_accum= 0;
 
-  if (op.aflags & adns_if_noerrprint) {
-    op.errfile= 0;
-    op.errcallback= 0;
-  }
+  if (op->errcallback)
+    scriptinv_set(&res->errcallback, ip, 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*)res : (void*)op->errfile);
   if (ec) { rc= posixerr(ip,ec,"create adns resolver"); goto x_rc; }
 
-  if (op.errcallback)
-    Tcl_IncrRefCount(op.errcallback);
-
-  *result= res;
+  *res_r= res;
   return TCL_OK;
 
  x_rc:
@@ -278,6 +341,36 @@ 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= {
@@ -338,20 +431,36 @@ static const OptionInfo query_optioninfos[]= {
 static int query_submit(Tcl_Interp *ip,
 			const AdnsTclRRTypeInfo *type, const char *domain,
 			int queryopts_objc, Tcl_Obj *const *queryopts_objv,
-			adns_query *aqu_r, void *context, OptionParse *op) {
+			adns_query *aqu_r, void *context, Resolver **res_r) {
   struct sockaddr sa;
   static const int aftry[]= { AF_INET, AF_INET6 };
+  OptionParse op;
+  OptionParse res_op;
   int rc, r, ec;
   adns_state ads;
   
-  op->aflags= adns_qf_owner;
-  op->sflags= 0;
-  op->resolver= 0; /* fixme default */
-  op->reverseany= 0;
-  rc= parse_options(ip, queryopts_objc,queryopts_objv, query_optioninfos,op);
+  op.aflags= adns_qf_owner;
+  op.sflags= 0;
+  op.resolver= 0;
+  op.reverseany= 0;
+  rc= parse_options(ip, queryopts_objc,queryopts_objv, query_optioninfos,&op);
   if (rc) return rc;
 
-  if (op->reverseany || (op->sflags & oisf_reverse)) {
+  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);
+    }
+  }
+
+  *res_r= op.resolver;
+  
+  if (op.reverseany || (op.sflags & oisf_reverse)) {
     const int *af;
     for (af=aftry; af < af + sizeof(af)/sizeof(*af); af++) {
       memset(&sa,0,sizeof(sa));
@@ -363,17 +472,17 @@ static int query_submit(Tcl_Interp *ip,
   af_found:;
   }
 
-  ads= op->resolver->ads;
+  ads= op.resolver->ads;
 
-  if (op->reverseany) {
-    ec= adns_submit_reverse_any(ads, &sa, op->reverseany,
-				type->number, op->aflags, context, aqu_r);
-  } else if (op->sflags & oisf_reverse) {
+  if (op.reverseany) {
+    ec= adns_submit_reverse_any(ads, &sa, op.reverseany,
+				type->number, op.aflags, context, aqu_r);
+  } else if (op.sflags & oisf_reverse) {
     ec= adns_submit_reverse(ads, &sa,
-			    type->number, op->aflags, context, aqu_r);
+			    type->number, op.aflags, context, aqu_r);
   } else {
     ec= adns_submit(ads, domain,
-		    type->number, op->aflags, context, aqu_r);
+		    type->number, op.aflags, context, aqu_r);
   }
   if (ec)
     return posixerr(ip,ec,"submit adns query");
@@ -428,18 +537,16 @@ static int synch(Tcl_Interp *ip, const AdnsTclRRTypeInfo *rrtype,
 		 const char *domain,
 		 int objc, Tcl_Obj *const *objv, adns_answer **answer_r) {
   adns_query aqu;
-  OptionParse op;
   Resolver *res;
   int rc, ec;
   
-  rc= query_submit(ip,rrtype,domain,objc,objv,&aqu,0,&op);
+  rc= query_submit(ip,rrtype,domain,objc,objv,&aqu,0,&res);
   if (rc) return rc;
 
-  res= op.resolver;
   ec= adns_wait(res->ads,&aqu,answer_r,0);
   assert(!ec);
 
-  asynch_check(res);
+  asynch_perturbed(res);
   return TCL_OK;
 }
 
@@ -490,11 +597,13 @@ struct Query {
   Tcl_Obj *xargs;
 };
 
+static void asynch_check_now(Resolver *res);
+
 static void asynch_timerhandler(void *res_v) {
   Resolver *res= res_v;
   res->timertoken= 0;
   adns_processtimeouts(res->ads,0);
-  asynch_check(res);
+  asynch_check_now(res);
 }
 
 static void asynch_filehandler(void *res_v, int mask) {
@@ -503,10 +612,12 @@ static void asynch_filehandler(void *res_v, int mask) {
   
   ec= adns_processany(res->ads);
   if (ec) adns_globalsystemfailure(res->ads);
-  asynch_check(res);
+  asynch_check_now(res);
 }
 
-static void asynch_sethandlers(Resolver *res, int shutdown) {
+static void asynch_sethandlers_generic(Resolver *res,
+				       int shutdown /*from _cancelhandlers*/,
+				       int immediate /*from _perturbed*/) {
   fd_set want[3];
   int maxfd;
   struct timeval tv_buf, *timeout;
@@ -528,13 +639,21 @@ static void asynch_sethandlers(Resolver *res, int shutdown) {
 	if (FD_ISSET(fd, &want[0])) mask |= TCL_READABLE;
 	if (FD_ISSET(fd, &want[1])) mask |= TCL_WRITABLE;
 	if (FD_ISSET(fd, &want[2])) mask |= TCL_EXCEPTION;
-	if (mask) Tcl_CreateFileHandler(fd,mask,asynch_filehandler,res);
-	else Tcl_DeleteFileHandler(fd);
+	if (mask) {
+	  Tcl_CreateFileHandler(fd,mask,asynch_filehandler,res);
+	  FD_SET(fd, &res->handling[i]);
+	} else {
+	  Tcl_DeleteFileHandler(fd);
+	  FD_CLR(fd, &res->handling[i]);
+	}
       }
+  res->maxfd= maxfd;
 
   Tcl_DeleteTimerHandler(res->timertoken);
 
-  if (timeout) {
+  if (immediate) {
+    res->timertoken= Tcl_CreateTimerHandler(0,asynch_timerhandler,res);
+  } else if (timeout) {
     int milliseconds;
 
     if (timeout->tv_sec >= INT_MAX/1000 - 1)
@@ -548,7 +667,17 @@ static void asynch_sethandlers(Resolver *res, int shutdown) {
   }
 }
 
-static void asynch_check(Resolver *res) {
+static void asynch_sethandlers(Resolver *res) {
+  asynch_sethandlers_generic(res,0,0);
+}
+static void asynch_cancelhandlers(Resolver *res) {
+  asynch_sethandlers_generic(res,1,0);
+}
+static void asynch_perturbed(Resolver *res) {
+  asynch_sethandlers_generic(res,0,1);
+}
+
+static void asynch_check_now(Resolver *res) {
   Tcl_Interp *interp= res->interp;
   adns_query aqu;
   adns_answer *answer;
@@ -558,7 +687,15 @@ static void asynch_check(Resolver *res) {
   int ec;
   Tcl_Obj *results[RESULTLIST_LLEN];
 
+  Tcl_Preserve(res);
+  
   for (;;) {
+    if (!res->ads) { /* oh, it has been destroyed! */
+      Tcl_Release(res);
+      return;
+    }
+
+    aqu= 0;
     ec= adns_check(res->ads, &aqu, &answer, &query_v);
     if (ec==ESRCH || ec==EAGAIN) break;
     assert(!ec);
@@ -567,7 +704,7 @@ static void asynch_check(Resolver *res) {
     query->aqu= 0;
     tabledataid_disposing(interp, query, &adnstcl_queries);
 
-    si= (!answer->status ? si= &query->on_yes
+    si= (!answer->status ? &query->on_yes
 	 : answer->status > adns_s_max_tempfail ? &query->on_no
 	 : &query->on_fail);
 
@@ -577,7 +714,9 @@ static void asynch_check(Resolver *res) {
     asynch_query_dispose(interp, query);
   }
 
-  asynch_sethandlers(res,0);
+  asynch_sethandlers(res);
+
+  Tcl_Release(res);
 }
     
 int do_adns_asynch(ClientData cd, Tcl_Interp *ip,
@@ -587,8 +726,7 @@ int do_adns_asynch(ClientData cd, Tcl_Interp *ip,
 		   int objc, Tcl_Obj *const *objv, void **result) {
   Query *query;
   int rc;
-  Resolver *res=0;
-  OptionParse op;
+  Resolver *res= 0;
   
   query= TALLOC(sizeof(*query));
   query->ix= -1;
@@ -598,23 +736,23 @@ int do_adns_asynch(ClientData cd, Tcl_Interp *ip,
   scriptinv_init(&query->on_fail);
   query->xargs= 0;
 
-  rc= query_submit(ip,rrtype,domain,objc,objv,&query->aqu,query,&op);
+  rc= query_submit(ip,rrtype,domain,objc,objv,&query->aqu,query,&query->res);
   if (rc) goto x_rc;
 
-  res= op.resolver;
+  res= query->res;
 
-  rc= scriptinv_set(&query->on_yes, ip,on_yes);   if (rc) goto x_rc;
-  rc= scriptinv_set(&query->on_no,  ip,on_no);    if (rc) goto x_rc;
-  rc= scriptinv_set(&query->on_fail,ip,on_fail);  if (rc) goto x_rc;
+  rc= scriptinv_set(&query->on_yes, ip,on_yes, xargs);  if (rc) goto x_rc;
+  rc= scriptinv_set(&query->on_no,  ip,on_no,  xargs);  if (rc) goto x_rc;
+  rc= scriptinv_set(&query->on_fail,ip,on_fail,xargs);  if (rc) goto x_rc;
   query->xargs= xargs;
   Tcl_IncrRefCount(xargs);
   *result= query;
-
-  return TCL_OK;
+  query= 0; /* do not dispose */
+  rc= TCL_OK;
 
  x_rc:
   if (query) asynch_query_dispose(ip, query);
-  if (res) asynch_sethandlers(res,0);
+  if (res) asynch_perturbed(res);
   return rc;
 }
 
@@ -622,7 +760,7 @@ int do_adns_asynch_cancel(ClientData cd, Tcl_Interp *ip, void *query_v) {
   Query *query= query_v;
   Resolver *res= query->res;
   asynch_query_dispose(ip, query);
-  asynch_sethandlers(res,0);
+  asynch_perturbed(res);
   return TCL_OK;
 }