--- lftp-3.3.5/doc/lftp.1.bz173276 2005-12-02 02:23:31.000000000 -0500 +++ lftp-3.3.5/doc/lftp.1 2005-12-16 20:07:19.000000000 -0500 @@ -919,6 +919,27 @@ .BR dns:use-fork \ (boolean) if true, lftp will fork before resolving host address. Default is true. .TP +.BR dns:use-first-address \ (boolean) +If true (the default), lftp will use the first address returned by a host name lookup; +if false, lftp will continue trying to find addresses of each address family +in dns:order until an address of each family is found, is authoritatively +known not to exist (as opposed to servers not being contactable), or the +dns:fatal-timeout (if any) expires. +Setting this to true will make lftp use the first available address for a name. +.TP +.BR dns:try-again \ (boolean) +If true (the default), lftp will continue to try to lookup a dns name while +no servers are contactable, until the dns-fatal-timeout expires or an address +is found (of each family in dns:order if dns:use-first-address is false). +If false, lftp will not retry dns name lookups . +.TP +.BR dns:n-attempts \ (number) +If zero, (the default), there is no limit on the number of times lftp will try +to lookup an address if dns:try-again is true. +If > 0, lftp will try only this number of times to look up an address of each +address family in dns:order . +If dns:try-again is not true, this variable has no effect. +.TP .BR file:charset \ (string) local character set. It is set from current locale initially. .TP --- lftp-3.3.5/src/resource.cc.bz173276 2005-11-08 02:21:19.000000000 -0500 +++ lftp-3.3.5/src/resource.cc 2005-12-16 20:02:48.000000000 -0500 @@ -341,7 +341,10 @@ res_timeout ("dns:fatal-timeout","0", ResMgr::UNumberValidate,0), res_order ("dns:order", DEFAULT_ORDER, OrderValidate,0), res_query_srv ("dns:SRV-query", "no", ResMgr::BoolValidate,0), - res_use_fork ("dns:use-fork", "yes", ResMgr::BoolValidate,ResMgr::NoClosure); + res_use_fork ("dns:use-fork", "yes", ResMgr::BoolValidate,ResMgr::NoClosure), + res_use_first ("dns:use-first-address", "yes", ResMgr::BoolValidate,ResMgr::NoClosure), + res_try_again ("dns:try-again", "yes", ResMgr::BoolValidate,ResMgr::NoClosure), + res_n_attempts ("dns:n-attempts", "0", ResMgr::UNumberValidate,ResMgr::NoClosure); static ResDecl fish_shell ("fish:shell", "/bin/sh", 0,0), --- lftp-3.3.5/src/Resolver.cc.bz173276 2005-11-08 01:17:11.000000000 -0500 +++ lftp-3.3.5/src/Resolver.cc 2005-12-16 20:20:09.000000000 -0500 @@ -682,6 +682,11 @@ time_t try_time; int af_index=0; int af_order[16]; + int af_tries[16]; + int af_try=0, af_tried=-1, try_afs_again=0; + int dns_use_first =ResMgr::QueryBool("dns:use-first-address",0), + dns_n_attempts=ResMgr::Query("dns:n-attempts",0), + dns_try_again =ResMgr::QueryBool("dns:try-again",0); const char *order=ResMgr::Query("dns:order",name); @@ -698,6 +703,8 @@ } ParseOrder(order,af_order); + + memset(af_tries, 0, sizeof(af_tries)); for(;;) { @@ -778,8 +785,32 @@ #else // !HAVE_GETADDRINFO int af=af_order[af_index]; + if(af==-1) - break; + { + if( (timeout == 0) + && (dns_try_again == 0) + && ((dns_n_attempts == 0) || (af_tried == 0)) + ) + break; + else + { /* tried all afs at least once */ + if( ( dns_try_again == 0 ) || (try_afs_again == 0)) + break; + + af_index = 0; + af = af_order[af_index]; + af_tried = 0; + try_afs_again = 0; + } + } + + if ( af_tries [ af_index ] != -1 ) + { + af_tries[ af_index ]++; + + if( (dns_n_attempts > 0) && ( af_tries [ af_index ] > dns_n_attempts) ) + break; struct hostent *ha; # if defined(HAVE_GETIPNODEBYNAME) @@ -801,12 +832,19 @@ } # endif - if(ha) + af_tried = 1; + + if ( ha ) { const char * const *a; for(a=ha->h_addr_list; *a; a++) - AddAddress(ha->h_addrtype, *a, ha->h_length); - af_index++; + { + AddAddress(ha->h_addrtype, *a, ha->h_length); + af_tries[ af_index ] = -1; + if ( dns_use_first ) + return; + } + af_index++; # if defined(HAVE_GETIPNODEBYNAME) freehostent(ha); # endif @@ -825,14 +863,33 @@ error=_("Host name lookup failure"); # endif } - af_index++; - continue; // try other address families + af_tries[ af_index ] = -1; } + } /* af_tries[ af_index ] != -1 */ + + if( af_tries[ af_index ] != -1 ) + try_afs_again = 1; + #endif /* HAVE_GETADDRINFO */ - time_t t; - if((t=time(0))-try_time<5) - sleep(5-(t-try_time)); + time_t t = time(0); + if( timeout && (( t - start_time ) >= (timeout - 1)) ) + { + return; + }else + { + af_try = (af_order[af_index+1] == -1) ? 0 : ((af_index + 1) & 0xf); + if( (af_tries[ af_try ] != 0) || (af_tried == 0)) + { + if( timeout == 0 ) + { + if((t-try_time)<5) + sleep(5-(t-try_time)); + }else + sleep(1); + } + af_index++; + } } }