Allow partial cache as as answer

When `CacheParallel` is on, there could be too many, exceeding buffer size.
lifenjoiner · Sep 23, 2024 · 2c5beac · 2c5beac
1 parent 154aa66
commit 2c5beac
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Showing 3 changed files with 49 additions and 15 deletions.
diff --git a/dnscache.c b/dnscache.c
@@ -690,11 +690,10 @@ static int DNSCache_GetRawRecordsFromCache(__in    const char *Name,
             break;
         }
 
-        Ret = 0;
-
         if( Node->TTL != 0 )
         {
             char *CacheItr;
+            int iRet;
 
             /* TTL*/
             if( IgnoreTTL == TRUE )
@@ -708,24 +707,19 @@ static int DNSCache_GetRawRecordsFromCache(__in    const char *Name,
             CacheItr = MapStart + Node->Offset + 1 + KeyLength + 1;
 
             /* Now the data position */
-            switch( Type )
+            iRet = g->Generate(g, Name, Type, Klass, CacheItr,
+                        MapStart + Node->Offset + Node->UsedLength - CacheItr,
+                        NewTTL
+                        );
+            if( iRet != 0 )
             {
-            case DNS_TYPE_CNAME:
-                if( g->CName(g, Name, CacheItr, NewTTL) != 0 )
-                {
-                    return -1;
-                }
-                break;
-
-            default:
-                if( g->RawData(g, Name, Type, Klass, CacheItr,
-                               Node->UsedLength - 1 - KeyLength - 1,
-                               NewTTL) != 0 )
+                if( Ret == 0 )
                 {
-                    return -256;
+                    INFO("Partial cache used for: %s\n", Name_Type_Class);
                 }
                 break;
             }
+            Ret = iRet;
         }
     } while ( TRUE );
 

diff --git a/dnsgenerator.c b/dnsgenerator.c
@@ -771,6 +771,36 @@ static int StripedLength(const char *Origin, int OriginLength)
     }
 }
 
+static int DnsGenerator_Generate(DnsGenerator *g,
+                                 const char *Name,
+                                 DNSRecordType Type,
+                                 DNSRecordClass Klass,
+                                 const char *Data,
+                                 int DataLength,
+                                 int Ttl
+                                 )
+{
+    int Ret = -256;
+
+    switch( Type )
+    {
+    case DNS_TYPE_CNAME:
+        Ret = g->CName(g, Name, Data, Ttl);
+        break;
+
+    case DNS_TYPE_A:
+    case DNS_TYPE_AAAA:
+    case DNS_TYPE_HTTPS:
+        Ret = g->RawData(g, Name, Type, Klass, Data, DataLength, Ttl);
+        break;
+
+    default:
+        break;
+    }
+
+    return Ret;
+}
+
 int DnsGenerator_Init(DnsGenerator *g,
                       char *Buffer, /* generate to here */
                       int BufferLength,
@@ -861,6 +891,7 @@ int DnsGenerator_Init(DnsGenerator *g,
     g->AAAA = DnsGenerator_AAAA;
     g->EDns = DnsGenerator_EDns;
     g->RawData = DnsGenerator_RawData;
+    g->Generate = DnsGenerator_Generate;
 
     return 0;
 }
diff --git a/dnsgenerator.h b/dnsgenerator.h
@@ -96,6 +96,15 @@ struct _DnsGenerator {
                    int DataLength,
                    int Ttl
                    );
+
+    int (*Generate)(DnsGenerator *g,
+                    const char *Name,
+                    DNSRecordType Type,
+                    DNSRecordClass Klass,
+                    const char *Data,
+                    int DataLength,
+                    int Ttl
+                    );
 };
 
 int DnsGenerator_Init(DnsGenerator *g,